NID Graduation Project - Gaurika Singhal - EustaCare, Innaccel Bangalore by Gaurika Singhal

GRADUATION PROJECT EustaCare: Biomedical System and Product Design for treatment of Eustachian Tube Dysfunction

Sponsor : INNACCEL, BANGALORE

Volume : 1 of 1 STUDENT : GAURIKA SINGHAL PROGRAMME : BACHELOR OF DESIGN (B. DES)

GUIDE : PRAVEEN NAHAR

2017 INDUSTRIAL DESIGN (PRODUCT DESIGN)

COPYRIGHT ÂŠ 2017 Student document publication meant for private circulation only. No part of this document can be reproduced or transmitted in any form or by any means electronically or mechanically, including photo copying, xerography or video recording without permission from the publisherGaurika Singhal & National Institute of Design. Edited & Designed By Gaurika Singhal gaurikasinghal@gmail.com www.behance.wnet/gaurikasinghal www.instagram.com/dekhogaurse Processed & Published At National Institute of Design Paldi, Ahmedabad - 380007 Gujarat, India www.nid.edu

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The Evaluation Jury recommends GAURIKA SINGHAL for the

Degree of the National Institute of Design IN INDUSTRIAL DESIGN (PRODUCT DESIGN)

herewith, for the project titled “EustaCare: Biomedical System and Product Design for treatment of Eustachian Tube Dysfunction” on fulfilling the further requirements by*

Chairman Members :

Jury Grade :

*Subsequent remarks regarding fulfilling the requirements :

Activity Chairperson, Education

Originality Statement I hereby declare that this submission is my own work and it contains no full or substantial copy of previously published material, or it does not even contain substantial proportions of material which have been accepted for the award of any other degree or final graduation of any other educational institution, except where due acknowledgment is made in this graduation project. Moreover I also declare that none of the concepts are borrowed or copied without due acknowledgment. I further declare that the intellectual content of this graduation project is the product of my own work, except to the extent that assistance from others in the projectâ&#x20AC;&#x2122;s design and conception or in style, presentation and linguistic expression is acknowledged. This graduation project (or part of it) was not and will not be submitted as assessed work in any other academic course. Student Name in Full: Gaurika Singhal Signature: Date:

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Copyright Statement I hereby grant the National Institute of Design the right to archive and to make available my graduation project/thesis/dissertation in whole or in part in the Instituteâ&#x20AC;&#x2122;s Knowledge Management Centre in all forms of media, now or hereafter known, subject to the provisions of the Copyright Act. I have either used no substantial portions of copyright material in my document or I have obtained permission to use copyright material. Student Name in Full: Gaurika Singhal Signature: Date:

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Disclaimer

This document contains information and imagery that is medically explicit. Please continue at your own discretion.

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EustaCare: Biomedical System

and Product Design for treatment of Eustachian Tube Dysfunction

CONTENTS ACKNOWLEDGMENTS

INTRODUCTION ABOUT – National Institute of Design – Graduation Project – Innaccel – Why Innaccel – The Team – The Project

15 17 17 17 18 18 19 21

PHASE ONE - MACRO RESEARCH – The Biodesign Process – Anatomy & Physiology – Disease State Analysis – How it Looks – Primary Research – Current Methods of Diagnosing ETD – Current Methods of Treating ETD – Medical Management of ETD – Teaching Biodesign at JIPMER, Pondicherry

23 24 28 32 34 36 46 50 54 56

PHASE TWO - DIVERGING – 10-Key Feature List – Constructing a Basic Need Statement – Work done on ET Project in 2015 – Brainstorming – Working towards Cadaver Study – The Cadaver Study

59 60 61 62 64 66 70

PHASE THREE - CONVERGING, MICRO RESEARCH – Need Statement Iteration – Constructing a Design Brief – Ideation & Conceptualisation – Filteration –Nasal Pack Concept – Micro Research - BET Papers – Why BET?

73 75 78 80 84 86 90 92

PHASE FOUR - DETAILING – Product constraints – Careflow – Competitor Analysis – About Balloon Tuboplasty – BET Prototyping – Sterilisation Methods – Clinical Trial – Addressing the Gaps – Anthropometry & Ergonomics – Product Specifications – EustaCare

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95 96 99 100 102 103 106 108 112 119 125 130

CONCLUSION – Concluding Comments – Looking Forward – Reflections & Learnings

137 138 139 140

GLOSSARY

142

REFERENCES

146

APPENDIX 151 – Cadaver Study Protocol – Cadaver Study Report – Clinical Consent Form – Tympanogram 1 - May 2017 – Tympanogram 2 - Sept 2017 – Product Specification Document – Observation Docket – Survey Responses

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ACKNOWLEDGEMENTS This graduation project wouldnâ&#x20AC;&#x2122;t have been possible without the support of all the people who helped me in this journey. I am extremely grateful to AVR for trusting me and giving me the opportunity to work on an intensive, hands on project. Pooja, for being an inspiring and patient mentor, for always pushing me to do better, for being an exhaustive resource of knowledge about medical devices and techniques, for helping me with the 36daysoftype challenge and for bringing me delicious rasam that soothed my nerves. Jagdish, for all the food & laughter, for an insight into the medical world, the process of surgery and for helping me discover a new dimension of myself. My guide, Praveen Nahar for painstakingly helping me pick the right graduation project, for making me think about and appreciate the role of a designer in the field of Biodesign and for always being ambiguous and forcing me to introspect and find my own answers. I would like to thank my friends and batchmates for believing in me and helping me whenever and however they could. Uttisht for giving me advice each time I got stuck and for always being there. Aboli for being a wonderful work buddy and for helping me click pictures of my prototypes. Sailee for all her warmth & support and for pushing me to get out more often. Sneha for patiently listening to my tantrums about layouts and typefaces and making the process of documenting so simple. Eleanor & Tyler for the lovely conversations and for accompanying me on my trips to SP Road. Muniraj Kaka for being such a cheery and helpful presence. Vishal for helping me with 3D modelling, rendering and always answering all my questions. Ram for getting me access to all the research papers I needed. Ranjitha for being calm and mothering. Aanan for volunteering to be a part of the clinical study. Yajurvi for all the help with interviews in Bombay. Maa for being my rock and for proofreading this document despite all its technical complexity & Papa for helping me make good decisions and encouraging me to follow my heart.

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INTRODUCTION Innaccel is a med-tech startup based in Bangalore that follows the Biodesign Process. The Biodesign Process is a globally recognised process developed by Stanford University to identify unmet needs in the healthcare sector; to brainstorm, invent and filter solutions and to implement them. Innaccel has a team of Engineers, Doctors and Business strategists who are currently working in the fields of ENT, Neurosurgery and Trauma. My graduation project involved creating an affordable surgical tool that could change the current ENT care flow, bring a brand new surgical technique to the Indian market and make it more accessible to patients. Innaccel gave me the resources to learn, implement and even teach the Biodesign Process. This intensive journey made it clear that, even a process as complex as Biodesign isnâ&#x20AC;&#x2122;t linear. I learnt the importance of precise and careful documentation and how an iterative approach affects the eventual outcome. I gained the confidence to acquire knowledge about unknown subjects quickly and engage in enriching conversations with experienced professionals like doctors and engineers.

This intensive journey made it clear that, even a process as complex as Biodesign isnâ&#x20AC;&#x2122;t linear.

Structure of the Document This project has been divided into four phases: Macro Research, Diverging, Converging & Micro Research and Detailing. These phases are followed by a Glossary, a list of References and an Appendix. The Glossary can be used to refer to definitions of most medical and technical phrases used in the document. These have been arranged alphabetically. The appendix contains some detailed protocols, reports that could not be included in the body of the document.

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ABOUT National Institute of Design The late 1950s saw a confluence of several forces, global and local making it a significant one for Indian culture and education. A young nation was confronted with the mammoth task of nation building, of balancing age old traditions with modern technology and ideas. There was a search for the Indian identity across all aspects of life. On April 7, 1958, Charles & Ray Eames presented the India Report to the Government of India which defined the underlying spirit that would lead to the founding of NID and beginning of design education in India. It recommended a problem-solving design consciousness that linked learning with actual experience and suggested that the designer could be a bridge between tradition and modernity. Based on the recommendations made in the India Report, the Government of India with the assistance of the Ford Foundation and the Sarabhai family established the National Institute of Industrial Design, as it was originally called as an autonomous all-India body in September 1961 at Ahmedabad. Today, NID is internationally acclaimed as one of the foremost multidisciplinary institutions in the field of design education and research. NID has been a pioneer in industrial design education after Bauhaus and Ulm in Germany and is known for its pursuit of design excellence to make Designed in India, Made for the World a reality.

Graduation Project The end of the students’ academic tenure at NID is marked by the culmination of a substantial investigation in the field of design on a topic closely allied to their discipline of study. It is through the graduation project and subsequent documentation of the same that this investigation takes place. This is the final academic project for the student. A jury comprising faculty members evaluates the students’ performance in the graduation project, after which, students are awarded NID’s professional education programme final graduation. The graduation project is an opportunity for students to demonstrate their expertise and must be done with academic rigour incorporating systematic inquiry and informed design decisions. The graduation project should reflect the thought leadership manifested through creativity and innovation. The project should lead to new knowledge creation and should align with broader objectives of the institute.

About 17

Innaccel InnAccel is Indiaâ&#x20AC;&#x2122;s first Medical Technology acceleration company focused on innovation for low and mid-income markets. InnAccel has built a proprietary innovation platform, and forged partnerships with national and global entities, to support startups and entrepreneurs. Innaccel is an evolving community of Engineers, Doctors and Designers working towards identifying opportunity areas in the healthcare sector and bridging the gaps with product and service interventions. They are supported by an extensive network of clinical advisors, hospitals, engineering colleges, technical consultants, mentors, strategic advisors, and business consultants. They are creating a portfolio of products that are designed, engineered, and priced for global emerging markets, including India. The company is led by an experienced management team and advised by industry leading experts. InnAccel is currently accelerating two companies, namely COEO Labs and Sattva MedTech. While COEO Labs is developing innovative medical devices in the space of Emergency and Critical Care, Sattva MedTech is developing a fetal monitoring device for use in the perinatal period to detect and monitor fetal distress.

Why Innaccel I was looking to do a graduation project that would give me a taste of an exhaustive process in a field I wasnâ&#x20AC;&#x2122;t very familiar with. My goal was to take up a challenging project that would push my limits and help me learn something entirely new. I had tried to explore Biodesign within the walls of NID by taking up a project in Neonatal Care for a course. Even though I was able to draw good insights through research and by interviewing doctors, I felt like the output suffered because there was no doctor or engineer on the team. This was a gap that Innaccel addressed because they believed in going through the whole process from need identification to the eventual solution in a team with doctors, business strategists and engineers on the team. Being at a startup, I would get the opportunity to drive my own project and play a key role in other projects that the team took up too. The prospect of working on a medical project that could eventually benefit a patient excited me!

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The Team Pooja Kadambi - Lead Systems Engineer She is a Biomedical Engineer from the University of Cincinnati, where she focused on Medical Device Innovation and Entrepreneurship. She heads the Eustachian Tube project.

A Vijayrajan (AVR) - Founder, CTO AVR is a MedTech veteran with 35+ years experience including stints as Head of Product Development at GE Medical Systems, Chief Executive at Wipro Health Sciences, and VP at Hewlett Packard.

Dr. Jagdish Chaturvedi - Director, Clinical Innovation He is a practicing ENT surgeon, Stanford-India Biodesign Fellow, and an MBA in Entrepreneurship and Hospital Management. A serial innovator, with over 20 inventions, his core expertise is in the process of identifying and analyzing unmet clinical needs for quick development of low-cost medical devices.

Aboli Joshi - Design Student Intern Eleanor Glockner - Biomedical Engineering Intern Tyler Dougan - Physicist, Intern Fellow interns at Innaccel who assisted with secondopinions and support through the various stages with this project.

About 19

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The Project The team had identified an unmet need in the ENT space, related to the medical management (diagnosis and treatment) of Eustachian Tube Dysfunction in an earlier clinical immersion. The Eustachian Tube/ auditory tube connects the nose and the ear. It is responsible for clearing the mucous from the middle ear into the nasopharynx and for stabilising middle ear pressure. When this ET function gets impaired, it needs to be treated. The current treatment methodology of ETD is symptomatic and has many gaps.

I was told that I would be working on the part of the need related to the treatment of ETD (Eustachian Tube Dysfunction).

About 21

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PHASE ONE Macro Research The Biodesign Process was understood. Primary and Secondary Research was conducted to grasp overall ENT anatomy, Eustachian Tube Anatomy & Physiology and Eustachian Tube Dysfunction. The current methodology of Diagnosis and Treatment was studied and a Medical Management chart was drawn out.

The Biodesign Process The biodesign innovation process begins with careful identification of a clinical need and moves in a stepwise approach through inventing and planning the implementation of a marketable solution. The design process started as a collaboration between Josh Makower and Paul Yock in the form of a training initiative as a part of the Stanford University Program.

Identify The identify phase involves directly observing the full cycle of care (diagnosis, treatment, recovery & billing) and discovering problems and opportunities. This is the most crucial part of the Biodesign Process and the other phases go smoothly if this is done right.

1. Need Finding Making Clinical Observations Clinical Observation/Shadowing gives individuals from any background an opportunity to observe clinicians provide care to their patients in a hospital/

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clinic setup. Itâ&#x20AC;&#x2122;s an immersive experience that lets one see the healthcare practitioner perform his daily duties closely and look for opportunities/gaps and problems in the taskflow. One also gets to see the functionality of a department and the interpersonal relationships between healthcare practitioners. A visual understanding of the context helps designers/ engineers make meaningful insights. It is important to document these insights on the spot in a comprehensive manner (like a docket) and look for cases which had an undesirable outcome. It is through these observations that one can ask crucial questions and find out what went wrong in the care flow and where the gap lies.

Forming a Need Statement A need statement is a synthesis of an observation. It expresses a desired change to a problem in who, where and why. It is directly derived from the understanding of the problem and must not be affected by the perceptions of the person making the statement.

2. Needs Screening Need Filtration Filtering needs from all the ones that are derived from the observation docket is necessary to derive the most crucial and viable needs. This is done in multiple levels. The first level (clinical validation) of filters are: frequency of negative outcome and criticality of negative outcome as per the clinician. The second level of filters (epidemiology filters) are intended to understand whether the identified need exists in other settings/hospitals in other parts of the country. The third level of filters (market landscape filters) is used to assess the market landscape for needs that have already proven to be important both in terms of market and magnitude. This is done using the parameters of Competitive landscape, technical complexity of predicate solutions, Buyer capacity and Regulator complexity.

Need Specification Document Needs Specification Document is a consolidated write-up of all the information relevant to the clinical need, the problem and the requirements for the solution. It helps to have a document like this for cross referal during different stages of the project. It contains the need statement, the clinical observation, disease state description, current care flow/treatment landscape, competitive analysis, stakeholder analysis, market size, market landscape

Developing Needs Criteria These are measurable criteria that help assess the viability of concepts and prototypes at different stages of the process. There are two kinds of needs criteria, must haves and nice to haves. Must haves are the core criteria that assess whether a concept passes or doesnâ&#x20AC;&#x2122;t. They include everything that the solution must achieve in order to solve the need. A concept should meet all the must haves to be viable. Nice to haves are extra criteria (added value) that could be met by the solution.

Phase One 25

Invent The invent phase includes brainstorming hundreds of potential solutions, organizing ideas and objectively comparing them against the needs criteria for satisfying the needs. Rough prototypes are created rapidly, so that failures emerge early and iteration can lead to better solutions. The surviving solutions are then researched on the basis of intellectual property issues, business models, reimbursement and regulatory pathways and then filtered. In the end, the process produces a lead concept that can be taken forward.

3. Concept Generation Ideation

The primary focus of a brainstorming and ideation sessions is to come up with as many concepts(approaches to the problem) as possible and embodiments(different ways to achieve the concept). This process is repeated a few times until a few concepts consistently meet the needs criteria every time and these are selected for making prototypes.

Developing a Proof of Concept

A proof of concept is the first prototype that shows the fundamental principles that drive the concept. It doesnâ&#x20AC;&#x2122;t need to look complete, but just demonstrate the concept well. It is important that the clinical basis of the concept is accurate.

4. Concept Screening By scoring the criteria that were explained in the need filteration section, different concepts can be weighed against each other. Another way of doing this can be by checking the concepts against the needs criteria (must haves and nice to haves) and seeing which ones are most likely to satisfy the need.

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Implement This phase is about taking the next steps in prototyping and testing the technology, developing an approach to patenting, regulatory approval, charting the market potential for the innovation, and exploring sources of funding.

Prototyping

Prototyping is a very crucial stage in the development of a product because it allows one to fail early. It makes it easier to find faults while making something because you find gaps in the planning. This kind of iteration by making and testing saves you from failing later on by saving huge costs in terms of time, effort, money and loss of credibility in the market. It also helps incorporate clinical inputs with each stage of prototyping to have the best version by the end.

5. Strategy Development The key strategies are: (1) intellectual property integrated with ongoing research and development and clinical plans, (2) regulatory strategy including process management and quality, (3) reimbursement strategy *

6. Business Planning This is by far the longest and most complex stage, with good reason. Regardless of the validity of the need, the ingeniousness of the concept and the size and scope of the market, at the end of the day, sound business underpinnings are essential if a product is to be delivered to the bedside, in a box, with a 1â&#x20AC;&#x201C;800 numbers on the side for sales and service. Getting to this reality requires a balanced consideration of the rules of the road from intellectual property, reimbursement, regulatory, and business models with the addition of a series of overlying and overlapping strategies. * (4) basic business blocking and tackling â&#x20AC;&#x201C; marketing, sales, and distribution, and (5) combining all assets and strategies together to develop a sustainable competitive business advantage.

Phase One 27

Anatomy & Physiology

Anatomy of the Eustachian Tube Source - Frankfurt Regional Medical Center

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Anatomy of the Eustachian Tube The Eustachian tube (ET for short), also known as the auditory tube, connects the ear (middle ear) to the nose (nasopharynx). In adults it is around 36mm in length. The ET in infants measures approximately 18 mm in length. It is about half the size of the adult eustachian tube and is generally more horizontal and less angulated. The inner lining of the Eustachian tube has columnar ciliated stratified epithelium. The cartilaginous part also contains some mucous glands. It has 3 parts: 1. Cartilaginous Part: It opens to the nasopharynx and is about 24 mms (2/3rd of the ET) in length. It is normally collapsed but contracts when you swallow or yawn due to positive pressure. The cross section of this part looks a bit like a bean. The nasopharyngeal opening is about 3-5 mms in diameter. 2. Bony Part: it is the part closer to the middle ear and is about 12 mms (1/3rd of the ET) in length. It is a bony structure with a mucosal lining on the inside. One end of the bony part of the Eustachian Tube opens to the eardrum/tympanic membrane. This part of the Eustachian Tube is close to the Carotid artery which supplies blood to the brain. 3. Isthmus: The length of the ET is hourglass-shaped with a narrowing in the middle where two parts (the cartilaginous and bony part) meet, called the isthmus. The isthmus is bony but has a mucosal lining and has an inner diameter of 5-7 mms. There are four muscles responsible for opening and closing of the Eustachian tube: 1. Levator veli palatini 2. Salpingopharyngeus 3. Tensor tympani

4. Tensor veli palatini: The tensor veli palatini and levator veli palatini contract while swallowing, pushing the soft palate upwards. This pulls the lateral wall of the cartilaginous portion medially and opens the tube before relaxing. When the muscles relax, the tube returns to its collapsed state. This happens periodically while swallowing, but can also be induced by yawning, chewing.

Physiology of the Eustachian Tube The physiologic functions of the eustachian tube are as follows: 1. Pressure regulation/equalization of the middle ear - The primary function of the Eustachian tube is to ventilate the middle ear space, ensuring that the pressure on both sides of the eardrum is equal for optimal vibration of the tympanic membrane, for proper transfer of sound waves. By periodically opening the middle ear to the outside environment, this pressure balance is maintained. 2. Protection of the middle ear from nasopharyngeal secretions and sound pressures 3. Clearance or drainage of middle ear secretions into the nasopharynx - The secondary function of the ET is to drain any accumulated secretions or gases to avoid infection, or debris from the middle ear space into the throat. Several small muscles located in the back of the throat and palate control the opening and closing of the Eustachian tube. Swallowing and yawning cause contractions of these muscles located in the back of the throat and help regulate Eustachian tube function. 4. Gaseous Exchange - The Eustachian Tube allows a gaseous exchange between the middle ear and the nasopharynx. For the tympanic membrane to vibrate in an optimal manner, this gaseous exchange is necessary.

Phase One 29

Anatomy of the Ear The ear is the organ of hearing and balance. The parts of the ear include: 1. External or outer ear, consisting of: a) Pinna or auricle. This is the outer part of the ear. b) External auditory canal/ tube. This is the tube that connects the outer ear to the middle ear. c)Tympanic membrane (also called the eardrum). The tympanic membrane divides the external ear from the middle ear.

Anatomy of the human ear Source - Fairview health services

2. Middle ear (tympanic cavity), consisting of: a) Ossicles. Three small bones that are connected and transmit the sound waves to the inner ear. The bones are called: i) Malleus ii) Incus iii) Stapes b) Eustachian tube. A canal that links the middle ear with the back of the nose. (refer to previous section) 3. Inner ear, consisting of: a) Cochlea (contains the nerves for hearing b) Vestibule (contains receptors for balance) c) Semicircular canals (contain receptors for balance)

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Physiology of the Ear The ear has two functions: 1. Hearing: Sound waves travel through the outer ear, are modulated by the middle ear, and are transmitted to the vestibulocochlear nerve in the inner ear, which transmits information to the temporal lobe of the brain, where it is registered as sound. 2. Providing balance: The ear facilitates two types of balance: static balance, which allows a person to feel the effects of gravity, and dynamic balance, which allows a person to sense acceleration.

Anatomy of the Nose

Physiology of the Nose

The nasal cavity is lined with nasal mucosa. The walls of the nasal cavity include the following features: 1. Roof 2. Floor: The part of the nose touching the soft palate. 3. Medial wall/nasal septum: bony section that separates the nasal cavity into the two nostrils. 4. Lateral wall: This wall is hallmarked by three nasal conchae/turbinates (superior, middle, and inferior) that project inferiorly from the wall. They divide the nasal cavity into four passages that have openings to the paranasal sinuses. The space under each turbinate is called a meatus. The inferior nasal meatus, found below the inferior nasal turbinate leads to the opening of the eustachian tube, along the floor of the nose.

The nose has three functions: 1. Breathing: The nose serves as the only means of bringing warm humidified air into the lungs. 2. Filteration: It is the primary organ for filtering out particles in inspired air, and it also serves to provide first-line immunologic defense by bringing inspired air in contact with mucous-coated membranes that contain immunoglobulin A (IgA). 3. Smell: Inspired air is brought high into the nasal cavity to come in contact with the olfactory nerves, thereby providing the sense of smell, which is intimately associated with the taste sensation.

Anatomy of the Nose Source - Health Life Media

Phase One 31

Disease State Analysis Eustachian Tube Dysfunction Eustachian Tube Dysfunction (ETD for short) is a condition where the Eustachian tube is unable to contract and retract and thereby unable to perform its functions (pressure regulation, drainage of mucous from ET, protection of middle ear from secretions).

Symptoms It is characterised by a constant feeling of ear blockage and ear pain due to a retracted eardrum. Other symptoms include muffled hearing, occasional or constant tinnitus (ringing sound) and a crackling sound in the ears

Causes There could be several causes for ETD: 1. Blockage at the nasopharyngeal opening of ET: Structures that block the ET prevent drainage of mucous and pressure equalization. These can be a) enlarged adenoids, b) enlarged turbinates or c) nasopharyngeal angiofibroma. Removing these structures restores the normal function. 2. Blockages inside the ET: Blockages inside the ET can be in two forms a) Mucous Plugs: Prolonged infections mean increased mucous production. This excess mucous can dry and create a physical blockage inside the ET lumen in the form of plugs. b) Polyps: Mucosal epithelium can develop into polypoid structures, though this is less likely.

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3. Inflammation/ Swelling: The inflamed tissue is heavier, making it more difficult for the muscles of the tube to open and close. This can affect both the inner lumen and the tissue around the nasopharyngeal end of the ET. This inflammation can be because of acute rhinitis due to infection, allergies or a deviated nasal septum (which makes turbinates enlarge and lead to a lack of space) 4. Fibrosis or scarring: Repeated inflammation and/or infections can cause trauma to the mucosal lining of the Eustachian tube. This leads to the development of fibrotic bands in the inner lumen of the ET, obstructing normal contraction and retraction of the cartilaginous part of the ET 5. Patulous Eustachian Tube: It is an idiopathic dysfunction of the muscles controlling the movement of the Eustachian Tube. It causes the Eustachian Tube to remain open, affecting its patency. This may be due to nerve damage. It has no definitive solution and requires constant medical management. However, this is a very rare condition. 6. Physiological differences (pediatric cases): The angle of the Eustachian tube is different in children and adults. Children have shorter, more horizontal Eustachian tubes which donâ&#x20AC;&#x2122;t drain middle ear fluid as easily, making them more prone to acute ETD and otitis media. 40% of all children under the age of 10 develop temporary ETD.

Otitis Media (OM) and ETD Infection in the middle ear that presents with fluid accumulation, inflammation and pain is called otitis media (OM for short). Eustachian Tube Dysfunction and otitis media are intrinsically linked. ETD prevents normal mucociliary clearance i.e. doesn’t allow middle ear fluid to drain into the throat. This fluid in the middle ear harbours bacteria or viruses that lead to ear infections. Resultant pressure differential leads to retraction, adhesion of eardrum and could cause a perforation if left untreated. This perforation causes temporary relief because of the release in pressure but makes the accumulated infected fluid flow out of the ear, also known as Acute Suppurative Otitis Media (ASOM). This would lead to reduced hearing and require constant medical management. Chronic otitis media (COM for short) recurs often because the underlying problem of ETD is not addressed. Instead, antibiotics and ear drops are regularly prescribed to treat just the infection.

Morbidity Eustachian Tube Dysfunction is very uncomfortable as it muffles the patient’s hearing and is painful. It leads to a reduced quality of life. Patients feel discomfort during flights and while diving. Untreated chronic ETD means constant negative pressure in the middle ear and therefore a constantly retracted eardrum. If the patient doesn’t receive treatment for the same, the eardrum may get perforated. Perforation gives a temporary sense of relief to the patient due to the sudden pressure equalisation, but in the long term results in hearing loss, increased ear infections and ear discharge. This can lead to permanent damage to the eardrum and hence permanent hearing loss.

Credits - Calvin & Hobbes by Bill Watterson Phase One 33

How it looks These diagrams show eardrums that demonstrate different grades of retraction (I - IV), otitis media and perforations, that all indicate Eustachian Tube Dysfunction. These are of relevance so as to understand the magnitude of the problem and treatment methodology. The last figure shows a treatment methodology - myringotomy, which will be described later in this document.

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Fig 1. Healthy Right Eardrum A healthy tympanic membrane has a beautiful cone of light and shows the handle of malleus.

Fig 2. Grade 1 retraction of the left eardrum with OME When the tympanic membrane gets pulled back enough to be close to the incus but not touching it (2nd ossicle) due to abnormal functioning of the ET and negative pressure in the middle ear.

Fig 3. Grade 2 retraction of the left eardrum When the tympanic membrane gets pulled back enough to be in contact with the incus (2nd ossicle) or the stapes (3rd ossicle) or is adherent to them.

Fig 4. Grade 3 retraction of the left eardrum When the tympanic membrane gets pulled back enough to touch the promontory (the beginning of the cochlea)

Fig 5. Grade 4 retraction of the left eardrum When the tympanic membrane is adherent to the promontory(The beginning of the cochlea).

Fig 6. Otitis Media with Effusion Fluid accumulation in the middle ear, colloquially referred as glue ear

Fig 8. Perforated Eardrum When negative pressure increases a lot, the eardrum perforates to allow a release.

Fig 9. Grommet Insertion a tiny incision is created in the eardrum (tympanic membrane) and a tube is inserted to relieve pressure caused by excessive buildup of fluid, or to drain pus from the middle ear

Fig 7. Suppurative Otitis Media is a chronic inflammation of the middle ear and mastoid cavity that is characterised by discharge from the middle ear through a perforated tympanic membrane

All images are from Otitis Media Guide (otitismedia.hawkelibrary.com)

Phase One 35

Primary Research Clinical Observerships Observing a healthcare professional provide care to patients in a clinical setting, such as a hospital, clinic etc. One gets to see what the day-to-day responsibilities of a health care giver might involve within a healthcare setting. It helps designers and engineers step into the shoes of the caregiver and understand the methodology of diagnosis and treatment of numerous diseases and symptoms. It helps them gain insights about any gaps in the caregiving process and make meaningful observations. These observations are recorded in observation tables which contain the time stamp, patient ID/name, the observation, the diagnosis and treatment, negative outcome, if any and eventually lead a designer to create a need statement with the collected information. Observation sheets can be found in the Appendix. ENT Camps around Bangalore The Indian Council of Medical Research (ICMR) is conducting a study over 8 centres across India to collect ENT data of various population groups. They have given a grant to St.John’s Medical College to collect ENT data of people living in and around Bangalore. St John’s, with Dr.Jagdish Chaturvedi has been pursuing this by means of a moving ENT van. This van is equipped with all the required equipment and moves from locality to locality treating patients and conducting audiometry tests. They’ve been doing this for 3 years and have covered 100 urban centres and treated 8577 patients. They record the occupations and the lifestyle of every area they go to. Patients who are treated by them have problems ranging from ear wax, hearing loss and Meniere’s disease. Such ENT camps were attended with Dr. Jagdish a few times to understand how he diagnoses and treats patients presenting differing symptoms and observations were made and recorded.

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Fortis, Bannerghatta Rd, Bangalore A month long observership was done at Fortis Hospital under Dr. Athira and Dr. Susheen of the ENT department They were observed in the OPD (Out Patient Department) diagnosing an average of 20 patients a day. These patients presented with symptoms indicating numerous diseases. Each of these cases was recorded in the observation table. The incidence of similar observations was marked. This experience helped understand the symptoms that can be used to diagnose ETD and also how similar symptoms can also indicate other diseases. The questions the doctors asks are very important to help proper diagnosis. For example, Ear pain and muffled hearing can be symptoms of both ear wax and ETD. The doctor usually asks the patient if they experienced pain after having a bath or if it was persistent all day. The patient’s answer to this question helps them conclude which of the two problems he/she could be suffering from. If the patient says that the pain usually increases after a bath, the doctor can easily conclude that the patient has a case of excessive ear wax and can continue to examine just the ear. Surgery at MENTS Hospital, Bangalore Several DNS (Deviated Nasal Septum) correction and balloon sinuplasty surgeries were attended at Meenakshi ENT Hospital. The posture of surgeons and nurses and the OT (Operation Theatre) setup was carefully observed. The methodology of operating - right from cleaning to operating and packing was noted. This gave a clear idea about the anatomy and of the usage of surgical equipment. It was also a thrilling experience to scrub in and stand in the OT. These observations led to the formulation of the treatment and care flow for ETD.

Dr. Jagdish Chaturvedi endoscopically checking a patientâ&#x20AC;&#x2122;s eardrum

Observing DNS Correction surgery in an OT at MENTS hospital

Phase One 37

Studying existing surgical instruments used in the nasal cavity A few days were spent in studyingÂ all the tools used by ENT surgeons in the nose. The aim was to understand the function of each tool, the ergonomics i.e the way the surgeon grips and uses them and the amount of force used. Close attention was paid to understand how doctors accommodate and use multiple tools like the endoscope and forceps in the nasal cavity to perform surgery. FESS stands for Functional Endoscopic Sinus Surgery. It is a basic nasal endoscopic surgery that every ENT surgeon performs. A range of handheld instruments are used while performing this surgery. These instruments are used to navigate through the nose, move aside structures that come in the way, grasp. clamp, cut or remove tissue and bone, to suture and stitch up tissue and to insert packing material. Most of them are made with surgical steel so that they can withstand various kinds of physical and chemical effects of body fluids, secretions, cleaning agents, and sterilization methods. They include different guages, endoscopes, forceps, turbinate scissors, suctions and probes.

38 Graduation Project | Gaurika Singhal

Studying FESS Instruments

Using an Endoscope & a ball probe

FESS Tools Study

Phase One 39

SinuCare Innaccel invented SinuCare in 2016. It is an affordable balloon sinuplasty system available in India. SinuCare is a device to enable a balloon sinus dilation (BSD) procedure in patients with Chronic Rhinosinusitis after medical management has failed to resolve the condition. SinuCareâ&#x20AC;&#x2122;s novel, patent-pending, double-balloon technology offers ENT surgeons a superior technology to dilate blocked or narrowed sinus openings. It is a minimally invasive treatment option for patients unwilling to or unable to undergo a FESS (Functional Endoscopic Sinus Surgery). Why is SinuCare relevant to this project? SinuCare is Innaccelâ&#x20AC;&#x2122;s first minimally invasive balloon product in the ENT space. The double balloon system approaches the sinuses through the nasal cavity. It is already being used in surgeries around India. It creates a good reference for ergonomics, usability, medical feasibility, patient satisfaction, technical feasibility and manufacturing. These aspects will be discussed in detail, later in this document. What are Sinuses/ Sinus Cavities? The sinuses are small, air-filled sacs in the nasal cavity behind your cheekbones and forehead. They produce a mucus lining that continually drains into the nose. The sinuses moisten the air we breathe, lighten the bones of the skull and serve as sound resonance chambers for speech. What is Sinusitis/Rhinosinusitis? Sinusitis or Rhinosinusitis is the inflammation of the sinuses resulting in thick mucous, plugged nose, headaches, sore throat and pain in the face. Chronic Rhinosinusitis (CRS) is sinusitis that lasts for more than 3 months. What is FESS? FESS or Functional Endoscopic Sinus Surgery is a surgical treatment of chronic sinusitis. It involves surgical removal of all structures (bone and tissue) that get in the way of the sinus and the cutting of the sinus osmium to enlarge it to allow the mucous to drain easily. This is a highly invasive surgery and the patient takes about 3 months to recover from it completely. What is Balloon Sinuplasty/ Balloon Sinus Dilation? Unlike traditional sinus surgery, Balloon Sinuplasty requires no cutting and no removal of bone and tissue. Balloon Sinuplasty (BSP) uses a small, flexible, balloon catheter to open up blocked sinus passageways and facilitate drainage of the mucus that builds up in patients suffering from chronic sinusitis symptoms. When the sinus balloon is inflated,

40 Graduation Project | Gaurika Singhal

it restructures and widens the walls of the sinus passageway while maintaining the integrity of the sinus lining. It is done under endoscopic view and does not include removal of any bones or tissues allowing the patient to return to normal activities quickly.

SinuCare: the guide, the double balloon system, the inflation system (with pressure guage) and syringe

Phase One 41

Nasal Anatomy and learning how to use SinuCare

Headmodel Training

In the first few weeks at Innaccel, training to use SinuCare in a 3D silicon nasal insert was provided. This was done in two parts; Nasal Endoscopy was taught first. An endoscope was used to explore and understand the structures of the nose. Even though nasal anatomy was studied in theory, it was challenging to grasp the nasal anatomy in 3D initially. It took persistent questioning and a lot of practice to get a hang of it. The positioning of the sinuses within the meatuses was learnt and navigating the depths of the nose using the endoscope with one hand and a septal elevator/ball probe in the other hand was mastered. The second part of the training was to do with using SinuCare; learning how to assemble the SinuCare guide and inflating and deflating the double balloon system with saline and a standard inflation pump with a pressure guage. After this, Sinucare was used in the silicon nasal insert. This exercise was repeated a few times to achieve expertise.

Training doctors at JJ Hospital

Learning this skill allowed hands on learning of anatomy and made it easier to estimate the size of instruments in the context of the available space.

Training Doctors and Eustachian Tube Project Survey It was discussed that after this, the design interns would train doctors to use SinuCare in a head model at conferences and forums in Bangalore and Bombay. Multiple training sessions were arranged by Innaccel at Meenakshi ENT Hospital, Bangalore and one at an ENT conference in Bombay called Mumbaicon. Responsibilities at each of these training sessions included manning the head model stall, interacting with and training doctors with varying experience to use SinuCare. This was also an opportunity to revise nasal anatomy with the doctors and gain more knowledge about the physiology and patency of the ET.

42 Graduation Project | Gaurika Singhal

Sinucare Training at Mumbaicon

Eustachian Tube Dysfunction Survey To take advantage of this opportunity where various ENT practitioners from the country would be found, a simple survey about ETD was formulated to gain insights for the project. This survey was framed to understand the number of patients that suffer from ETD on a regular basis, to find out how different doctors diagnose and treat ETD and to learn if they knew about or believed in newer practices like Balloon Eustachian Tuboplasty (BET). The survey included these questions: 1. How many patients do you see daily? (OPD & Surgery) 2. How many of your patients have ear diseases? (like otitis media, otitic barotrauma, acute suppurative otitis media) 3. How many of the patients with ear diseases have ETD? 4. What is your first line of treatment for patients with ETD? eg. nasal spray, medication, grommet insertion, self-inflation maneuvers 5. In how many ETD patients does the first line of treatment resolve the issue? How many patients come back with the same complaint? 6. What is the next line of treatment if the first line has not resolved the issue? 7. What are the challenges you face in diagnosis and treatment of ETD? eg. time, process of elimination, responsiveness to treatment 8. Do you do any physical Eustachian Tube intervention? Why / Why not? Eustachian Tube dilation systems exist in the West. What do you think of them? 9. Do you see value in visualising the Eustachian tube lining till the isthmus for diagnosis and treatment? In what scenario? Do you do it today? If so, how?

Surveying doctors about ETD at Mumbaicon

Phase One 43

Eustachian Tube Dysfunction Survey Responses On interviewing 41 ENT specialists from around the country, the results were as follows:

Years of experience â&#x20AC;&#x201C;

Classification of doctors interviewed on the basis of experience/ practice in the field More than 15 years Less than 15 years

In an ENT OPD, doctors see â&#x20AC;&#x201C;

46.5 930

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Patients daily (on average) Patients monthly (on average)

Patients with Eustachian Tube Dysfunction –

Patients with Eustachian Tube Dysfunction:

32.5%

ETD patients who don’t respond to first line of treatment:

40% of them

Percentage of Doctors interest in trying an intervention device –

Doctors interested in physical ET Lumen Intervention:

68.2%

This data collected from ENT surgeons at the conference and the hospital, helped validate the need for a physical Eustachian Tube intervention. All Survey Responses collected can be found in the Appendix at the back of the document.

Phase One 45

Current methods of diagnosing ETD Eustachian tube dysfunction has a mix of functions and pathologies linked to the condition making it difficult to find a single method that would definitively identify the cause. These are the various methods of diagnosing Eustachian tube dysfunction today and doctors usually adopt a combination of these to identify the underlying cause and treat suitably.

Rigid Endoscopy

Flexible Endoscopy

Source - Pocket Atlas of the nose & paranasal sinuses

Doing an endoscopy can provide information on the nasal anatomy and inflammation. Endoscopy along with the patient’s history can be used to diagnose acute ETD caused by rhinitis and allergies. A 70 degree angled endoscope can be used to inspect the nasopharyngeal opening of the ET. Patients can be asked to swallow or yawn with the endoscope in place to see the patency of the ET. Limitations This is useful if the cause is simply inflammation or a physical blockage outside the ET. However, if the cause is fibrosis or blockage inside the ET lumen, it cannot be identified using endoscopy Cost to Patient - Rs. 400 to 800

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Source - ENT for children

Flexible, steerable endoscopes smaller than 2mm in diameter can allow visualisation inside the Eustachian tube lumen. The patient undergoes a local anaesthetic and the scope is passed through the nose. The tip of the scope can be steered into the ET orifice. Bursts of air through the instrumentation channel push soft tissue out of the way and allow visualisation till the isthmus. Limitations • Difficult to maneuver. • Very expensive. • Air flushing at high pressure can damage the eardrum. Cost to Patient - Rs. 6000-12,000

Tympanometry

Equalisation Maneuvers

A tool to test the condition of the middle ear and mobility of the eardrum. It helps identify the presence of middle ear fluid and patency of the Eustachian Tube. Sound waves are bounced off the eardrum by the tympanometer. By measuring the difference in the generated sound and the reflected sound, the condition of the middle ear is concluded.

On a regular basis, the Eustachian tube opens on swallowing and yawning. During diagnosis of Eustachian Tube Dysfunction, doctors may ask patients to perform some equalization maneuvers to assess the level of dysfunction. Patients with physical blockages in the Eustachian Tube lumen and patulous Eustachian tubes will not feel any relief from these. The most common ones are: 1. Toynbee Maneuver- Swallowing while pinching the nose to push compressed air into the Eustachian Tube. 2. Valsalva Maneuver - Pushing of air into the Eustachian Tube by closing the nose and blowing outwards. 3. Politzer Maneuver - Blowing air up the nose with an air pump while swallowing. 4. Voluntary opening of the Eustachian tube - Some patients are able to tense the muscles controlling the Eustachian tube while moving their jaw to voluntarily equalise the pressure. This is the gentlest method.

Source IndiaMart

Limitations â&#x20AC;˘ Patients with a perforated eardrum cannot be tested. â&#x20AC;˘ It cannot tell the underlying cause of Eustachian Tube Dysfunction. Cost to Patient - Rs. 500 to Rs.1000

Limitations They have limited use in diagnosis. It does not give any clear indication of the cause of dysfunction. Cost to Patient - None

Phase One 47

Radiological Imaging

Sonotubometry

Conventional X-Rays

This test conveys sound from the nose to the ear via the Eustachian tube. The sound is captured from the ear and the difference between the volume in the nose and ear is recorded. A properly functioning Eustachian Tube will transmit more sound than one that is closed or blocked. Since this test doesn’t need to perforate the eardrum, it’s a way to non-invasively test Eustachian Tube function. Limitations Sonotubometry only confirms Eustachian Tube Dysfunction but doesn’t give an idea of the cause for the dysfunction. Cost to Patient - Unknown (New method of diagnosis)

X-rays of the mastoid bone can show the level of aeration of the temporal bone. This is an indirect indicator of the ET function.

MRI & CT Scans These can visualise the lumen of the Eustachian Tube if taken at high resolution & when the lumen is at least partially open. Patients are made to tilt their heads for this. Sometimes they are asked to perform and hold the Valsalva maneuver during the scan to increase the contrast. MRI is better at showing the differences between mucous, soft tissue and bone than CT scans. It is also good at showing variable thickness of the mucosal lining of the Eustachian Tube.

Source ResearchGate

Limitations 1. Radiological imaging is expensive and timeconsuming. 2. None of these methods have entered regular practise due to the level of technical skill required to conduct them. 3. Many of these tests require a tympanic perforation or grommet, making them less than ideal for most patients. Cost to Patient MRI - Rs.8000 - Rs.13000 CT - Rs.3000 - Rs.5000

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Tubomanometry

9-step inflation – deflation test

This technique employs a defined pressure in the nasopharynx that is monitored in the external ear canal using a pressure sensor to get an idea of the Eustachian Tube function and opening. This method can be used for both intact and perforated eardrums. It is still undergoing clinical trials and is yet to be adopted into usual practise.

This is an elaborate test introduced almost 40 years ago. It requires an intact eardrum and a dry middle ear. Tympanometry is performed to record middle ear pressure at rest and with applied pressure. A series of inflations is performed to assess the capability of the Eustachian Tube to perform pressure equilibration. However, the predictive value of the test is questionable. Sometimes, patients with good Eustachian Tube function may still fail certain steps of the test. This test is not widely used due to its elaborate and long procedure.

Limitations 1. Doesn’t tell the cause of ETD 2. Very costly 3. Still under development. Cost to Patient - Unknown (will be similar to tympanometry)

Limitations 1. Doesn’t tell the cause of ETD 2. It requires an intact eardrum and a middle ear without effusion, limiting the number of patients it can address. 3. Very elaborate procedure Cost to Patient - Unknown

Phase One 49

Current methods of treating ETD The current treatment of Eustachian Tube Dysfunction is mostly symptomatic, with few methods addressing the root causes. This in part, is because there are no ways to definitively identify the cause of ETD. Doctors usually treat ETD conservatively using medicines like decongestants, nasal sprays and mucolytes. This helps reduce any amount of swelling in the nasal passage Sometimes, a saline spray is prescribed for a longer period of time to help treat problems due to physiological deformities (like a deviated nasal septum, turbinate enlargement etc).

Catheterisation

Equalisation maneuvers

Source IndiaMart

The Eustachian Tube catheter is a long, thin metal instrument mainly used to flush the Eustachian Tube with air or water to help remove obstructions (like mucous) and to open up the tube to equalise middle ear pressure. Usually, the catheter is inserted under the view of an endoscope into the nose and water or air is flushed into the Eustachian tube. Sometimes suction is applied through it to get any foreign particles from the tube. Since catheterisation is often done blind, it doesn’t allow the doctor to confirm whether the treatment worked. There has been widespread distrust of the technique in the last three decades since the ET is considered to be an easily damaged structure. Suction and flushing can cause trauma to the middle ear and eardrum. Limitations • No way of knowing whether it worked or not. • Air and water flushing or suctioning at high pressure can damage the eardrum. • Not a long lasting treatment. • Obsolete methods because of the risks Cost to Patient - Rs. 500-2000

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Source Enkimd.com

Performing Valsalva, Toynbee and Politzer maneuver regularly can help with symptomatic relief of ETD. These maneuvers not only help doctors diagnose ETD by making air enter the Eustachian tube, but also relieve negative pressure and retractions. By forcing the ET to open, any mucous present inside drains out more easily. Limitations • Unknown long-term benefits of these maneuvers Cost to Patient - None

Myringotomy/Grommet Insertion

Adenoid & Fibroma Removal

Refer to Fig. 9 on page 35 One of the major symptoms of ETD is ear pain caused by repeated ear infections and fluid buildup (OME) in the middle ear. A large portion of the population with ETD is pediatric. Pediatric cases require a more procedurebased solution than the clearing maneuvers called grommet insertion (aka tympanostomy, ventilation tube insertion, myringotomy). A grommet is a small tube with fluted ends that is placed by making a slit in the eardrum. The tube equalises pressure and allows drainage of any middle ear fluid, keeping the ear dry. This aids treatment of ear infections. As the perforation heals over 6 to 18 months, the eardrum pushes the grommet out. There is an initial drop in hearing levels which is regained a little after the eardrum heals. Limitations • Mainly useful for children. • Not recommended for adults because it could lead to permanent hearing loss. • It cannot be used for patients whose eardrums are naturally perforated. Cost to Patient - Rs. 20,000-50,000

Source CBS News

Often, the underlying cause of Eustachian tube dysfunction is swollen adenoids or fibrous structures blocking the nasopharyngeal opening. This is most common in children and adolescents. Adolescent boys are at high risk of nasopharyngeal angiofibroma, which are benign vascular tumours at the back of the throat. Removal of these via an endoscopic surgery can unblock the opening of the ET and restore its function. Limitations The surgery won’t work if the underlying cause of the patient’s discomfort is more than just the physical blockage. Cost to Patient - Rs. 25,000-50,000

Phase One 51

Correction of faulty nasal anatomy

Source drtaherian.com

The nose is a self-correcting system that compensates for any structural abnormalities by vascularising sections to continue regular function. If the septum is deviated, there is more air passing through one nostril than the other. Hence, to maintain the warming and moistening of incoming air, the turbinates get highly vascularised and swell up. Over a long period of time, the turbinates engorge further and further leading to a blocked nose. For some people, their particular nasal anatomy causes the back of the hypertrophic inferior turbinate to block the opening of the Eustachian tube. Deviated nasal septum (DNS) also leads to a general oedema of the mucosa. This results in the classic symptoms of ETD even if the ET itself is perfectly normal. Correcting the nasal anatomy by straightening the septum and reducing the size of the turbinates can resolve symptoms of ETD. Limitations If the cause of ETD is a physiological problem in the ET itself, this surgery will not resolve the symptoms and the patient will need a further procedure. Cost to Patient - Rs. 30,000-80,000

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Tympanoplasty

Source google sites

When a patient comes in with a discharging ear/ perforated eardrum, he/she is counselled for a tympanoplasty. Tympanoplasty is a surgical procedure in which the eardrum and/or ossicles are repaired. The eardrum is reconstructed using a graft from the patient’s temporalis fascia. In most cases, it relieves pain and infection symptoms completely. It is successful 70-80% of the time. It is usually more likely to work for younger patients. Limitations • The acceptance rate is higher for younger patients because they heal faster. • It doesn’t work for patients who don’t naturally perforate their eardrums or have constantly discharging ears. Cost to Patient - Rs. 20,000-50,000

Balloon Eustachian Tuboplasty (BET) Balloon dilation of the Eustachian tube is a recently developed technique to treat chronic ETD. A balloon catheter is inserted through a hollow guiding tube into the cartilaginous part of the Eustachian tube from the nasopharyngeal opening. It is inflated at 8 to 10 atmospheres of pressure for up to two minutes. The high pressure balloon causes radial dilation of the cartilaginous portion of the Eustachian Tube. Limitations • BET is still not fully established as a technique, and many doctors are still unsure of the safety and efficacy of the balloon dilation systems available in the market today. • It isn’t available in India. • While clinical trials have proven promising, there are no studies yet on the effects of BET over 10 years. Cost to Patient - over Rs. 1 lakh

Phase One 53

Medical Management of ETD This flowchart shows the current flow of diagnosis and treatment as practiced by a caregiver in a hospital/clinical setting for patients who complain of symptoms of Eustachian Tube Dysfunction. The flowchart shows the two stages at which suffering patients come and how doctors and clinicians manage it using various techniques & tools. It shows the logical steps taken by the caregiver to arrive at the right diagnosis and provide treatment. This chart is also called the treatment flow.

Patientâ&#x20AC;&#x2122;s Symptoms

Diagnosis Ear wax seems to be clogging the ear

Grade I Retraction of eardrum

Asked about allergies, nasal block

Treatment Pathway

54 Graduation Project | Gaurika Singhal

prescribed soliwax for a week, asked to come back for cleanup if required

symptomatic treatment with mucolytes, saline spray, decongestant

Yes

Ear Pain, Blockage, Muffled Hearing

Discharging Ear

Examination with headlamp or an otoscope to check eardrum Grade II, III, IV Retraction of eardrum

Acute Suppurative Otitis Media

Anterior rhinoscopy, Asked history No visible indicators

Adolescent Male (14 -17yrs) High Risk of nasopharyngeal angiofibroma

Deviated Nasal Septum/ Enlarged turbinates

Nasal Endoscopy

Nasopharyngeal Angiofibroma

Adenoids or other masses

Counseled for removal of these masses

No visible indicators

symptomatic treatment with mucolytes, saline spray, decongestant If worsened, Myringotomy recommended

Nasal spray, medication, decongestant for 7-10 days

Mopping, maintaing dryness for ten days If worsened, tympanoplasty is recommended

Phase One 55

Teaching Biodesign at JIPMER, Pondicherry A three day long Biodesign workshop was conducted at Jawaharlal Institute of Postgraduate Medical Education and Research, Pondicherry. Innaccel believed that the best way of learning something was to teach it to someone else. The young medical students were given a crash course in Biodesign. This was arranged so that the skill of observing and inventing could be inculcated in them and they could use their medical knowledge to create solutions to solve problems that surround them. The structure of the workshop was decided and tools were arranged. A presentation describing the process was made and various exercises were thought of to engage and involve the audience. The students were asked to make teams, take up a simple observation and follow the process to create a solution to address the gap. This was then reviewed at the end of the workshop. it was a great experience and helped reiterate the Biodesign Process.

Conducting a Biodesign Workshop at JIPMER

56 Graduation Project | Gaurika Singhal

Facilitating a team in constructing a need statement

Phase One 57

58 Graduation Project | Gaurika Singhal

PHASE TWO Diverging An initial guideline was made in the form of a list of features that the final product would have and an initial need statement; Different ideas were thought of and tested in a cadaver. A cadaver study protocol and report was prepared.

10-Key feature list A list of ten key features that the eventual product that would help surgically treat Eustachian Tube Dysfunction (ETD) was made on the basis of all the information gathered through primary and secondary research. This served as a basic guideline for the first brainstorming. Since no visualisation tool can currently enter the Eustachian Tube. it was assumed that the tool would work with visualisation (with the help of a 70 degree endoscope) only until the nasopharyngeal opening. 1. The tool has to go through the nasopharyngeal opening of the Eustachian Tube. 2. It should be smaller than the cartilaginous part of the ET but larger than the isthmus in diameter so that it doesn’t enter the bony part of the Eustachian Tube. 3. The tool should be angled according to angle x (unknown at this point) of the Eustachian Tube to the wall of the nasopharynx. 4. The tool should not pose any risk to the carotid artery which is housed close to the bony portion of the Eustachian Tube. 5. The tool cannot be used in case of certain blockages without viewing, like nasopharyngeal angiofibroma, cancer and adenoids) 6. If the tool is a dilator, it has to stay in the Eustachian Tube for x time to ensure dilation. 7. It must be made of a biocompatible material and be minimally invasive 8. It should be able to work along with a visualisation instrument/ endoscope. 9. It should have an ergonomic grip for the doctor to use. 10. It should be able to fight the apprehension from doctors about using a new surgical approach.

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Constructing a basic need statement A need statement is just like a design brief but adapted for opportunities and gaps in the medical space. It helps designers and engineers narrow down to the crux of the problem and also serves as a benchmark when deciding concepts. It is a single statement that incorporates what problem needs to be solved, in what way, in whom, where and why. It usually follows a simple format – A desired change to the problem + Who + Why + Where

Eustachian Tube Anatomy Source - Pinterest

A desired change/ What – What it is that needs to be changed today in order to eliminate a problem. Who – Who is being affected by the problem today? Where – This takes into consideration the infrastructure and resources that may be available at the location of potential use. Why – What is the most important reason for addressing this problem On the basis of all the knowledge grasped about the Eustachian Tube and ETD, construction of a need statement for the project was attempted. What – Effectively treat Eustachian Tube Dysfunction (ETD) Who – Patients with chronic ETD Where – in an ENT OPD Why – avoid middle ear diseases So, The need is to effectively treat ETD in patients with chronic ETD in an ENT OPD to avoid middle ear diseases.

Phase Two 61

Work done on ET project in 2015 The need finding and validation for the Eustachian Tube Project i.e the gaps in the diagnosis and treatment of ETD was done in 2013. In 2015, A team worked on a device that addressed the gap of medical management of Eustachian Tube Dysfunction. This device was supposed to visualise the tube and dilate it too. Three cadaver studies were conducted to understand the angle, strength of the tube and to eliminate some concepts. It was found that balloon dilation worked, that the isthmus was narrower than 1 mm in diameter and an understanding was gained about the type of materials that could be used in the Eustachian Tube. A brief market study and patentability search was done to assess the IP landscape with the help of an indian law firm. The search concluded in October 2015 that patentability was poor as there was enough prior art on the use of mirrors, endoscopic camera visualization, balloon dilation etc. There was a unanimous decision that patentability could be re-evaluated later if some novelty was added to the materials or indirect diagnostic approaches were explored with simultaneous intervention techniques. The solution created at the time was not satisfactory and made the company realise that the problem needed to be tackled step by step. Thus it was divided in two parts: Treatment (Dilation of the ET) and Diagnosis (Visualisation of the ET).

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Inspecting the Nasal Cavity with a thudicun speculum

Brainstorming Factors that were known 1. Length of the Cartilaginous part of the ET, until the isthmus is approximately 24 mm in most adults 2. The isthmus (the narrowing between the cartilage and the bone) is approximately 1.5 mms in diameter 3. The cartilaginous portion of the ET is approximately 3 mms when it collapses and 5 mms when it expands. 4. On the basis of previous cadaver studies done in the field, the angle of the ET was estimated to be between 50-60 degrees. Efforts were made to think of ways to 1. Approach the Eustachian Tube from the nose. 2. Enter the cartilaginous part of the ET, find out the right angle. 3. Open/Expand/Dilate the ET to drain out any accumulated mucous. Options included modifying existing tools that are used in the nasal cavity like forceps and probes and/or making new ones from scratch. The idea was to think of the whackiest ideas and then formulate them into viable concepts later. This process was done without any bias or judgement but using the need statement, the key features and the known factors in mind. Technical feasibility was ignored at this point.

64 Graduation Project | Gaurika Singhal

Quick sketches done during brainstorming

Phase Two 65

Working towards a Cadaver Study A human cadaver is a dead body donated to science that can be legally used to study anatomy and to verify surgical techniques before moving on to live patients. A cadaver study is an organised exploratory study that aims to assess the feasibility of certain techniques or to measure and examine anatomy. Cadaver studies are conducted in labs of teaching hospitals with access to all sorts of surgical tools and equipment.

A cadaver study was required to access, dilate and visualise the inside of the Eustachian tube.

For the purpose of the project, a cadaver study was required to access, dilate and visualise the inside of the Eustachian tube. It was also critical to measure the angle of access to the Eustachian Tube and the length and diameter of the cartilaginous portion of the ET. The strength of the cartilaginous wall also had to be determined so as to assess how stiff the tool could be. This section includes information about the prototypes created, the list of study questions, protocol followed, the conclusion. The Cadaver study Protocol, Report can be found in the Appendix at the back of this document. Prototyping Ideas from the first brainstorming session were selected. Very little filtration was done at this stage. Most concepts that could be prototyped were made to be tested in the cadaver. It was decided that the concepts would be picked on the basis of whether or not they work in the cadaver and then refined. Even ideas that worked externally or on entry through the ear instead of the nose were prototyped. The cadaver study was done for the overall project i.e. diagnosis and treatment. Tools to visualise the ET and to expand/dilate the ET were arranged for/made. A lot of this was done by modifying existing visualisation tools like endoscopes and flexible endoscopes. The visualisation tools to be used were - A 0/30 degree endoscope to travel through the nose till the opening of the Eustachian Tube, A 70 degree endoscope to visualise the opening of the WET, A flexible endoscope to fit into the ET and a fibre optic cable to illuminate the bony portion of the ET Some modifications and attachments were built to aid these functions, like an 80 degree guide to push the fibre optic cable from the ear to the isthmus. a guide for the flexible endoscope to smoothly into the Eustachian Tube and a whisk like attachment for the tip made with nitinol to avoid the muck from tissue, mucous/blood and to ensure that the passage got cleared as the scope entered the Eustachian Tube.

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Modified Giraffe Forceps

Modified Bipolar Forceps

Numerous approaches to dilate the ET were prototyped: . Type 1 - Mechanical Opening - To stretch open the cartilaginous portion of the Eustachian Tube with almost a tong like motion. This was prototyped in two ways: Dremel Vibrating Attachment

a) Modified giraffe – The giraffe has been bent at a 55 degree angle. The surface area of the jaws has been increased to create petal-like shapes. b) Bipolar forceps – Bipolar forceps with rubber band wrapped around the handle. Markings have been placed to move the band and change the size of opening Type 2 - External vibration to assist the opening of the ET to allow the mucous to drain, this was to be done using a Dremel vibrator – A coneshaped addition to the engraving attachment of the dremel to be used to provide vibration in the ear canal Type 3 - Using pressure to force out any excess mucous/ mucous plugs from the ET or to open out the collapsed walls of the ET. This was to be done with: a) Air pressure nozzle – Canned air with an attached tube and Eustachian tube catheter which will be used to move mucous from the ET

Air Pressure Nozzle

b) Water flushing nozzle – Syringe attached by a pipe to the Eustachian tube catheter to flush water through the Eustachian Tube.

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Conical mechanical dilator

Guides for balloon dilation

Type 4: Mechanical Dilation - Using an external instrument to mechanically enlarge and open out the cartilaginous ET. This was to be done using Conical probes – Ball probes bent to 55 degree angle with a cone-shaped tip Type 5 - Balloon Dilation - A method in which a balloon catheter is inserted in the Eustachian Tube and inflated up to a pressure of 10-12 atmospheres and then deflated, to dilate the ET. This method is relatively new and is currently being used only in the west. This was to be carried out by: a) Adapting the company’s Sinucare, balloon sinuplasty balloon by removing the distal balloon and rounding the tip with m-seal. Guides with angles (50, 53, 55, 60) were 3D printed to be used with a modified Sinucare balloon.

Sample Balloons

b) Sample balloons of varying stiffness and lengths were collected from balloon manufacturers. c) An Existing balloon system for ET dilation from the company, Acclarent called Acclarent Aera was arranged for, to see how it works. Type 6 - Absorption and Dilation - The idea was to use something similar to a sponge that could be inserted in the ET to absorb mucous and intern expand as it did to dilate the cartilaginous portion of the ET. This was prototyped using Nasal Packs. Nasal Packs are tampon like inserts for the nose that are used to soak up excess blood post surgery. These nasal packs come in a condensed tight form and expand on contact with fluid and almost triple in size. Small pieces of nasal pack were cut to the size of the ET and the idea was to insert them into the ET of the cadaver and irrigate them to make them expand.

Nasal Pack + ET Catheter

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Study Questions Study Questions are the questions that determine how successful each technique used in the cadaver study will be. They are constructed by defining the role of every prototype and characterising what would make it a success or a failure. They also include general questions about the anatomy of the cadaver. They define the overall purpose of the study. It was realised that assumptions had to be made about how the prototypes were to perform. Questions were built holding these assumptions as normal. 1. 2. 3. 4.

Did vibration help loosen and release mucous from the ET? Did pressurised air help loosen and release mucous from the ET? Did a stream of water help loosen and release mucous from the ET? Was access angle suitable to access ET opening nasally? Which angle was suitable for accessing the ET opening? 5. Was stiffness of system suitable to enter ET? (for each of the prototypes) Which prototype worked with no damage? 6. Was there indication that the isthmus was reached? Tactile feedback and/or visual confirmation 7. Was transillumination visible with the fibre optic? 8. Was visualisation into the ET achieved with the mechanical opening devices? Which scope? to what extent could you see? 9. Was visualisation achieved with the flexible endoscope? What was the length to which it was able to enter? 10. Were there any problems during visualisation? 11. Did the whisk attachment push obstructions out of the way without blocking the view of the scope? Which size? Did both sizes fit? 12. Did prior dilation impact the visualisation clarity and access (for camera insertion only)? Which kind of dilation? 13. Could the fibre optic be visualised inside the ET when fibre optic is passed into ET from the ear and the scope light is off? 14. Was balloon dilation of ET achieved? With which balloon, any damage. Was any permanent stretching observed? 15. How long was it required to keep the tool in to ensure dilation? For each balloon sample 16. Was any damage caused to the bony part of the ET? Was any other damage caused to the ET? With what prototypes/techniques? 17. Was it easier to access the Eustachian Tube through the nasal passage or pharyngeal passage? What are the advantages and disadvantages of both approaches? 18. Did the nasal pack swell up? With surrounding moisture or added moisture? 19. Did the nasal packs dilate the cartilaginous part of the ET? Any visible changes, permanent stretching? 20. Did vibration from the ear canal move the nasal pack out of the ET? 21. Did the conical probe help dilate the ET?

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The Cadaver Study The Cadaver study was conducted over seven hours under the supervision of Dr. Jagdish Chaturvedi (certified ENT surgeon and Director, Clinical Innovations and Partnerships at Innaccel) and Dr. Mohan Jagade (Professor and Head of Department, ENT and Head and Neck Surgery, JJ Hospital). The setup had two male cadavers with intact eardrums and nasal anatomy, though only one of the cadavers was used. An endoscope, equipped with a camera and an overhead screen was provided for visualisation and the whole endoscopy was recorded on a CD. A portable mobile endoscopy unit and an endoscopy camera was arranged for visualisation through the flexible endoscope. All prototypes were laid out on a table for easy access. The nose and the ear of the cadaver were cleaned out and prepared for the study. The protocol was followed as planned with a few exceptions. Observations were noted with time stamps.

Setup for the Cadaver Study

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Cleaning out the cadaver nose & ear

Dr. Jagade operating on the ear

Conclusion/ Learnings

A two-step approach incorporating both the balloon dilation & the nasal pack could be adopted.

The vibration method at the mastoid did not work at all. The bone did not transmit the vibrations to the cartilaginous part of the ET, thus having no effect on it. The method of using pressure to force the ET open using air or flushing with water is not medically feasible as it damages the tympanic membrane. Mechanically opening the ET worked only at the opening, but made the ET collapse back again. The balloon dilation and nasal pack absorption method worked well. There isnâ&#x20AC;&#x2122;t a definite way of knowing that the nasal pack approach worked because it was inserted in a non functioning ET and there are no studies or literature regarding this. A twostep approach incorporating both the balloon dilation and the nasal pack could be adopted.

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PHASE THREE Converging, Micro Research Need Statements were iterated and a Design Brief was made. This led to a formal ideation and conceptualisation. These concepts are then filterated and a few directions were chosen. Micro Research was done and a concept was finalised.

â&#x20AC;&#x153;Remember, it's the problem that decides the need; Not me, or you, or anyone else.â&#x20AC;? - Dr. Jagdish Chaturvedi

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Need Statement Iteration The need statement is a well articulated statement that sums up and points to the gap for intervention. It is crucial to have a perfect and precise need statement because it structures the solution. The need statement that was formulated before the cadaver study on the basis of primary and secondary research was: 1// The need is to effectively manage ETD in patients with chronic ETD in an ENT OPD to avoid middle ear diseases. After the cadaver study, the need statement was iterated multiple times to define the gap perfectly. This was done over a few days alongside ideation. 2// The need is to accurately treat ETD in patients with chronic ETD in an ENT OPD to avoid middle ear diseases.

3// The need is to effectively (safe, definitive, affordable, accessible way) to treat chronic ETD in patients with chronic ETD in an ENT OPD/ outpatient setting in order to prevent middle ear diseases and complications.

4// The need is to effectively (safe, definitive, affordable, accessible way) to treat chronic ETD in adult patients who are non responsive to medication (Maximal Medical therapy) in an ENT OPD/ outpatient setting in order to prevent middle ear diseases and complications.

It was realised that the word ‘effectively’ was not definitive. Hence attempts were made to explain ‘effectively’, better in the context of the need.

Accuracy is not the only gap in the current medical management of ETD. There are multiple factors that affect the treatment of the disease. The eventuality that has to be avoided could be a perforation of the eardrum or deterioration of the ossicles or low hearing.

It was recognised that the target audience for this need were not just people who were suffering with chronic ETD but specifically adults suffering from chronic ETD & were non responsive to medication. Affordability and accessibility to not affect the effectiveness of the solution. Hence they do not determine the need but should be included in the must haves as they are parameters that affect the reach of the final solution. The need statement and the much haves were revised to include these changes 75

Must haves are meant to be definitive guidelines for the final solution/ intervention. They list out all the conditions that a product must have, to fulfil the need. Some of them are derived directly from the need statement while others are dependent on anatomy, physiology and cost. Nice to haves are additional features that a product may have. These are not essential but usually point to the direction that the next iteration can take. Must haves 1. Should be able to use it in an outpatient setting. 2. Intervention should provide real time information up till the cartilaginous portion of the ET 3. Shouldn’t enter the eustachian tube beyond the isthmus or cause damage to the carotid artery 4. Should not cause injury to the inner lining of the cartilaginous part of the eustachian tube beyond the surface epithelium. 5. Should not cause any irreversible damage to the tympanic membrane. 6. Post intervention, shouldn’t require the procedure again for at least a year. 7. should be a quick procedure – 15 minutes (dependent on doctor’s time) 8. cost of the procedure shouldn’t be more than 50% of the cost of the nasal endoscopy.

Nice to haves 1. Allow multiple interventions like suctioning, drug delivery to the Eustachian Tube directly 2. Work in paediatric patients 3. Intervention should provide real time information of the entire length of the Eustachian Tube.

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How long the effect of a treatment lasts is not controlled by the product; it has to do with the feasibility of the technique being employed in the process. Thus this is not a valid must have. Most treatment procedures in the ENT space are not carried out in the outpatient or daycare setting. Since this would be the first of its kind, it would be hard to compare it to existing diagnostic procedures, like nasal endoscopy that happen in the OPD.

5// A need to safely and definitivelyÂ treat chronic ETD occurring in adult patients who are do not respond to medication in an ENT OPD/ outpatient setting in order to prevent middle ear diseases and complications. Must haves 1. Should be able to use it in an outpatient setting. should be a quick procedure â&#x20AC;&#x201C; 20 minutes 2. Should not be able to enter the eustachian tube beyond the isthmus. 3. Should not cause injury to the inner lining of the cartilaginous part of the eustachian tube, the carotid artery or irreversible damage the tympanic membrane. 4. Cost of the procedure shouldnâ&#x20AC;&#x2122;t be more than? Nice to Haves 1. Allow multiple interventions like suctioning, drug delivery to the Eustachian Tube directly. 2. Work in paediatric patients. 3. Provide real time information of the entire length of the Eustachian Tube.

This synthesised need statement was still not satisfactory. It was realised that despite multiple iterations, there were still gaps and errors. This was because, the problem demands that the entire medical management of ETD, from diagnosis to treatment be addressed. A need statement for the treatment of ETD could not be made singularly. Diagnosis is an essential part of the gap in the current management of the disease. However the scope of the project demanded focus only on the treatment of the disease. Thus a design brief was formulated.

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Constructing a Design Brief It was concluded that a need statement for a gap related to the treatment of Eustachian Tube Dysfunction would be incomplete without addressing diagnosis because they are interdependent. Diagnosis in this case would point to the visualisation of the Eustachian Tube which provides doctors accurate information to identify and treat the cause of the problem. The company was looking to find a solution for treatment and diagnosis independently because of technological constraints. A solution of treatment in this case would be blind i.e would not be guided with visualisation (an endoscopic view) beyond the nasopharyngeal opening of the Eustachian Tube. Since a need statement could not be constructed, it was decided that a design brief would be made. A design brief is a plan that defines the product's goals and attributes, and gives direction to the project. Unlike a need statement, it is more general. It doesnâ&#x20AC;&#x2122;t have to address the entire problem, which in this case is the medical management of ETD (diagnosis and treatment). So a design brief was created as a guideline for a product that would help with the treatment of Eustachian Tube Dysfunction.

A design brief is a plan that defines the product's goals and attributes, and gives direction to the project.

1// To make a minimally invasive surgical method / instrument(s) for doctors and clinicians to help 1. mechanically remove blockages, 2. relieve middle ear pressure and 3. dilate the cartilaginous part of the eustachian tube of adult patients suffering for chronic Eustachian Tube Dysfunction, from the nasal passage with visualisation only up till the nasopharyngeal opening, without causing trauma to the patient; so as to prevent middle ear diseases and complications. This method/instrument shouldnâ&#x20AC;&#x2122;t enter beyond the isthmus as it might fracture the bony portion and cause irreversible damage to carotid artery. It shouldnâ&#x20AC;&#x2122;t cause injury to the inner lining / mucosa of the cartilaginous part of the eustachian tube or cause any irreversible damage to the tympanic membrane. This method/instrument should work along with an endoscope/other visualisation and other tools like ball probes until the opening of the ET and be ergonomic for the doctor to use. This method/instrument should be able to enter the eustachian tube at the required angle and be made of biocompatible materials. It should be a safer, faster, accessible, more affordable and accurate way of treating the patient than existing methods like tympanoplasty.

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Final Design Brief

This was made more concrete and comprehensive into a final design brief 2// To create a safe, affordable device to allow for intranasal treatment of the cartilaginous portion of the Eustachian tube when filled with extra fluid or narrowed from fibrosis for adults suffering from chronic ETD. Factors impacting safety under standard use: 1. Cannot perform suction, biopsy, or insert hard instrumentation without real time visualisation 2. Should not be able to pass into the isthmus and in any way access the boney part of the ET and middle ear 3. Should not be able to perforate cartilage or tear cartilaginous tube at attachment point Constraints: 1. Should work along with standard rigid or flexible nasal endoscopesÂ 2. Current instrumentation does not allow visualisation within ET, just till the opening in choana 3. Will not know the root cause of ET before intervention 4. Should not require an OT.

Dr. Jagdish helping frame the design brief

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Ideation & Conceptualisation The learnings from the cadaver study, primary and secondary research and history of the project formed the basis of the ideation. The ideation session was conducted for the overarching need statement and must haves. This was to involve the whole team. Later, treatment and diagnosis ideas were filtered on the basis of the need statement and the must haves, separated and validated. The overarching need statement and must haves were: A way to effectively manage ETD in patients with chronic ETD as daycare to avoid middle ear diseases. Must Haves 1. Real time data on physiology and positioning 2. Cost of goods sold < Rs 5000 per patient 3. Suitable for adolescents and adults with chronic ETD 4. Should not cause permanent damage to bony portion of the ET, Middle Ear or TM 5. Should match skill level of ENT practicing Endoscopy 6. Patient should be fit to resume basic biological and occupational functions within 24 hours of the procedure 7. Should treat the identified cause of chronic ETD 90% of the time without recurrence of the condition for a year Nice to Haves 1. Cost of goods sold < Rs 500 per patient 2. Suitable for pediatric use 3. Matches skill level of an MBBS student 4. Chronic ETD should not recur for at least 3 years 5. Complete management in the OPD

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The ideation session involved thinking of different ways in which the Eustachian Tube could be treated and diagnosed. These were not specific ideas but just an outline of the approach that could be adopted. These were: 1. Nasal physical lumen intervention with real time lumen information. 2. Nasal physical lumen intervention with real time information only until the Eustachian Tube 3. Eustachian Tube exercise assisting device 4. External Face tool with contact 5. Delivery of substances into the ET 6. Endaural approach (via the ear) 7. Replacing the Eustachian Tube 8. No direct body contact 9. Oral approach 10. Systemic Drug Delivery 11. Other or Invasive techniques

After these directions were decided, different methods of executing these approaches were conceptualised. The team conceptualising was multidisciplinary. It comprised of a doctor, two biomedical engineers, a physicist and two designers. This made for a lot of interesting ideas. Each approach was taken up and various ways in which ETD could be tackled using that approach were thought of. These were: 1. Nasal physical lumen intervention with real time lumen information. • Endoscope with an attachment that can be inserted into the ET • Balloon Catheter + Camera • Conical Probe + Camera • A sensor that can be placed at the eustachian tube that Dilates it as and when required • An instrument that mechanically opens out the ET and has a camera housed within • Robotic Monitoring Spider - a small instrument planted at the opening of the ET that collects real time information and performs some dilation. • Probe based Cryo/ Thermal Therapy 2. Nasal physical lumen intervention with real time information only until the Eustachian Tube • Blind Balloon Dilation - Balloon dilation assisted with an endoscopic view only till the opening • A nasal pack used to absorb excess mucous and dilate the ET • Umbrella like mechanical dilator • Saccharin Clearing Pack Test - A nasal pack can be placed in the ET and saccharin can be injected into it. This can be used to determine whether a patient has a functioning ET based on whether or not he/she tasted the sweetness • Cryotherapy or Thermal Therapy inside or around the Eustachian Tube 3. Eustachian Tube exercise assisting device • A device that works through the mouth and nose and assists the patient to perform toynbee • A device that assists a patient to swallow • A device that helps perform valsalva while introducing a dye during an MRI • Impedance mapping cap/mask with pressure actuators • Nasal pillcam, shows if exercise is being done correctly • Earbud tympanometry and exercise trigger

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4. External Face tool with contact • Face Vibration • High Intensity Focussed Ultrasound Patch • Thermal Therapy near the ear and jaw • Acupressure / Foot Reflexology - points that relieve ear pain. 5. Delivery of substances into the ET • Straw/ Nozzle that delivers steam, saline and air • Self push and suck - thin tubes threaded into ET with valve in the mouth to blow air/suck • balloon/sponge reservoir in nasopharynx that releases substance on swallowing • A catheter with an inner channel camera tip and an outer lumen to pass fluid/air 6. Endaural approach (via the ear) • myringotomy where grommet can be used to deliver medication. • A small device that sits outside the tympanic membrane, in the ear and gathers information about the ET • Boomerang device that delivers air, liquid or vibration - has camera • Myringotomy where Grommet acts as channel for a guide wire - pass balloon, visualisation • Needle with hinge that enters with small prick in eardrum and bends into bony part • Bent scope that has a channel, extremely thin that can enter bony canal • Vibration in ear canal, measured from the opening of ET to assess function and break up mucous 7. Replacing the Eustachian Tube • Cartilage Transplant - Transplant of the cartilaginous portion of the ET • Artificial ET (Like Pacemaker) • Only replace cartilaginous part with a sensor which activates with movement of soft palate, camera aperture like structure • Permanent remote-controlled grommet • Permanent remote-controlled tube in place of ET

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8. No direct body contact • Sound Waves • Gamma Wave Radiation • Pressure Chamber • Laser Beam (Microwave) • Cryo, Thermal chamber for head • Elevator drop and rise to open and close ears • swimming pool pressurised jets of water - pool treatment 9. Oral approach • Palatal Vibration • Transoral Access + intervention through catheter/ probe 10. • • • • • • •

Systemic Drug Delivery Naso pharyngeal drug patch Secretion flushing drug Tongue patch/tongue Piercing for drug delivery Pack with drug at nasopharyngeal opening + inject sugar dye Mucolyte pump sensor delivers to nose when needed injected drug liquid that settles as a patch in the nasopharynx - gets ingested bit by bit on swallowing Pill cam drug coated for ET

11. Other or Invasive techniques • Nerve Stimulation • Create external fistula (abnormal connection between organs) from cartilaginous ET to the neck • Cranial Nerve Impact • Vascular Intervention • Orbital Access (through the eye) • ET Pacemaker • Palatal Pacemaker • Mandibular implant - Jaw implant that heats, cools and stuimulates nerves • Scrape Eustachian Tube and let mucosa regenerate

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Filtration First filtration Once there was good understanding of what each approach encompassed, the approaches were filtered on the basis of the needs criteria. It was important that the selected approach met all the needs criteria specified as per the overarching need (diagnosis +treatment). Each approach was measured against the first must have. The ones that didn’t meet the first one weren’t assessed further at all. This was repeated till all the must haves had been used to check the approaches.

It was important that the selected approach met all the needs criteria specified as per the overarching need

For the purpose of this exercise, the second approach i.e, ‘Nasal physical lumen intervention with real time information only until the nasopharyngeal opening’ was combined with the first approach ‘Nasal physical lumen intervention with real time information’ because one of the must haves of the overarching need is real time data on physiology and positioning. The two approaches are very similar with the exception of not having visualisation inside the ET lumen. Though, it can be argued that visualisation is not the only way of getting real time data on physiology and positioning.

The two filtered approaches were: • Nasal Approach • Oral Approach.

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Second filtration Both the Nasal and Oral approach have similarities because they target the Eustachian Tube via the nasopharynx. When compared further, the Nasal intervention is more practical than the oral intervention. This is because it is easier for the doctor to visualise the ET from the nasal cavity (ET is in the back of the nose) and the patient is likely to gag when a tool is inserted into the oral cavity. Thus the nasal approach was selected.

Nasal intervention is more practical than Oral intervention.

Third filtration Next the different concepts under nasal physical lumen intervention were assessed on the basis of their treatment ability i.e. their ability to treat the various causes of Eustachian Tube Dysfunction and then the practicality of making them within technological constraints.

When checked on the basis of ability to treat the many causes of ETD, only balloon dilation checked most of the boxes. On the basis of concept filteration methods and the cadaver study, it was clear that Balloon Eustachian Tuboplasty was the most practical method of treatment of Eustachian Tube Dysfunction. Some of these techniques could not be validated for the causes of ETD because of lack of medical research about them. For example, there is no proven research that suggest that cryotherapy or thermal therapy helps reduce inflammation of the ET.

On the basis of concept filteration methods and the cadaver study, it was clear that Balloon Eustachian Tuboplasty was the most practical method of treatment of ETD

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Nasal Pack Concept A nasal pack is sterile packing material used to absorb excess blood from the nose after surgery. It is similar to a tampon. It comes in a compressed hard form and becomes spongy on soaking any liquid. The concept of using a thin section of a nasal pack in the Eustachian Tube to absorb mucous and in turn make it expand due to it’s sponge like nature was a novel one. Secondary Research was done through various medical research databases and it was ascertained that this technique had never been looked into for the absorption of mucous.

A nasal pack is sterile packing material used to absorb excess blood from the nose after surgery.

It was evaluated in the Cadaver Study. A thin section of a nasal pack (about 6 mm in thickness and 20 mm in length) with a thread at its end, was inserted into the tip of a Eustachian Tube Catheter. The catheter was then lead to the nasopharyngeal opening of the ET under endoscopic visualisation. It was then pushed out from the tip of the catheter into the opening using a wire from the rear end of the catheter. The nasal pack was left in the ET for a minute. Forceps were used to pull the nasal pack using the thread at its end. Even though it seemed to have absorbed excess mucous and dilated the eustachian tube (when checked with a 70 degree endoscope placed at the opening), it isn’t known whether it would work in a living human being. It was unknown if: 1. The pack would absorb all densities of mucous 2. The pack would be able to make a semi-functioning/ functioning ET expand despite the pressure exerted by the muscles to make the tube collapse 3. Upon insertion, the pack would push mucous from the cartilaginous portion of the ET into the bony portion through isthmus. 4. It would push mucous plugs in further and worsen the condition. The advantages of this method if it were to work would be: 1. It would be minimally invasive and not cause damage to any of the delicate structures casing the ET. 2. Doctors would be able to use it to deliver medication directly to the ET 3. Since doctors are accustomed to inserting packing material in the nose, they would be more accepting of this technique and won’t require training.

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It is unknown if the pack would absorb all densities of mucous or if it would cause the required effect. to dilate the Eustachian Tube.

Cutting the nasal pack to the dimensions of the ET

A Nasal Pack, compressed and swollen

Adding honey to make a mucous simulation

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Mucous Simulation and Testing Samples of various densities of mucous were made to check the absorption capacity of the nasal pack. Mucous is mainly composed of proteins and sugars. It is sticky and stringy because of the presence of these two substances.

Mucous simulations were made to check the absorption capacity of the nasal pack.

A mucous sample was poured into a syringe flask and a nasal pack was inserted. It was then timed to see how long it took to swell up to its full capacity. It was pulled out after it fully soaked mucous and readings of the flask capacity were taken.

The results showed that thicker lumpy mucous would not get absorbed by the nasal pack and thus the nasal pack wouldnâ&#x20AC;&#x2122;t work if the patient had ETD because of mucous plugs.

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Why the Nasal Pack approach was not taken forward 1. There are no studies to show the viability of using nasal packs to absorb mucous. 2. There is also no way of knowing whether it would cause the required crush injury on the walls of the Eustachian Tube.

Mucous Simulation

3. To check the viability of the concept, it would have to be tested in a living human being and not a cadaver.

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Micro Research - BET Papers The cadaver study pointed to Balloon Eustachian Tuboplasty as the most viable method of achieving ET dilation and as a treatment of ETD. It was known that the pressure exerted by the balloon makes the walls of the Eustachian Tube dilate and that allows the mucous to drain and equalises middle ear pressure but the long term viability of this technique and the technical reasons behind its working was unknown. To reiterate the research done so far, research papers related to ETD, Balloon Eustachian Tuboplasty, it’s effects and why it works, were read. The list of these papers can be found in the Appendix at the back of this document.W

The most important papers were: 1. Evidence and evidence gaps in the treatment of Eustachian tube dysfunction and otitis media Teschner M1, 2016 2. Histopathology of balloon-dilation Eustachian tuboplasty.- Kivekäs I1, Chao WC, Faquin W, Hollowell M, Silvola J, Rasooly T, Poe D, 2015 3. Balloon Eustachian Tuboplasty: a retrospective cohort study - Schröder S1, Lehmann M1, Ebmeyer J1, Upile T1, Sudhoff H1, 2015

A balloon catheter inserted into the Eustachian Tube

An inflated balloon in the Eustachian Tube

Source - ScienceDirect.com

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Key insights: 1. In balloon dilation, there is no attempt to dilate the bony portion of the ET because the pathology is most commonly located within the cartilaginous segment, and balloon dilation of the bony portion would create a significant risk to the internal carotid artery that is immediately adjacent.

The pathology is most commonly located within the cartilaginous segment

2. The exact mechanism of balloon dilation in the ET is most likely a crush injury to the epithelium of the Eustachian Tube created because of the pressure of the balloon. However, this crushing spares the basal layer, allowing for rapid healing. Additionally, it appears to effectively crush lymphocytes and lymphoid follicles that may become replaced with thinner fibrous scar. These effects reduce the overall inflammatory burden and may provide lasting clinical improvement in ET dilation and ventilation.

The exact mechanism of balloon dilation in the ET is most likely a crush injury to the epithelium of the Eustachian Tube

3. Studies in Germany conducted on a total of 622 (1076 ears) patients show significant improvement over 5 years. Long term results show a success rate of 70%

BET has shown significant improvement in patients in a study done over 5 years.

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Why BET? Eustachian tube dysfunction (ETD) is a common medical issue, occurring in at least 1 % of the adult population. Patients suffering from ETD typically present with complaints of hearing loss or sensation of pressure or plugged ear, which can lead to impaired quality of life. Over time ETD can result in conductive hearing loss or choleastatoma formation. Effective therapeutic options for ET dysfunction are few. The natural history of Eustachian tube dysfunction is poorly understood, and evidence for current treatments are limited.

Over time ETD can result in conductive hearing loss or choleastatoma formation.

Balloon Eustachian Tube Dilation is a novel and safe surgical procedure. It produces significant improvement in tympanogram values up to 15 months post-operatively. There are studies indicating that its effects last for almost 5 years. Being minimally invasive, it is a day-care procedure and can be done in the OPD.

BET is a safe surgical procedure. There are studies indicating that its effects last for almost 5 yrs.

It helps treat most of the common causes of ETD like inflammation of tissue, fibrosis and scarring due to repeated inflammation by crushing the epithelium of the inner lumen and allowing it to regenerate. In case there are blockages at the nasopharyngeal opening of the ET, a surgeon can surgically remove these before dilating the cartilaginous Eustachian Tube. In case of mucous plugs inside the ET, tactile resistance would be felt by the surgeon on insertion of the balloon and this would help with diagnosis. The patient would be prescribed mucolytes and balloon eustachian tube dilation would be performed if required.

It helps treat the common causes of ETD like inflammation, fibrosis & scarring by crushing the epithelium of the inner lumen and allowing it to regenerate.

However, it cannot help treat a patulous eustachian tube and it cannot be used in pediatric patients yet. Studies are being done to determine whether BETD would work for children but there are no definite results. The angle of the Eustachian tube is different in children and adults. Children have shorter, more horizontal Eustachian tubes that vary. Adult vs. Infant Eustachian Tubes Source - Foundation Chiropractic Co

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Meeting with Dr. Jagdish about finalising the approach

Phase Three 93

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PHASE FOUR Detailing This phase involved prototyping, conducting a clinical trial, collecting feedback and addressing the gaps in the entire system. Ergonomics studies were conducted and a product specification document was drawn out. The product was 3D modelled and made ready for manufacturing.

Product Constraints Product Constraints were made as a guideline for the new approach. These were specific constraints related to anatomy, dimensions, materials and safety. The Product - A balloon catheter with a guiding tube to help treat Eustachian Tube Dysfunction (ETD) in patients with chronic ETD by entering the Eustachian Tube (ET) via the nasal passage and dilating the cartilaginous part. Anatomical Constraints 1. Length of cartilaginous part of the ET - 24 mm (20 24 mm) 2. diameter of Â ET - 3 mm 3. diameter of isthmus - 1mm (0.5 - 1.5 mm) 4. maximum diameter that the cartilaginous ET allows - 6mm 5. angle of entry into the ET - 55 degrees (50 - 55 degrees in adults Other Instruments that will be used alongside 1. Endoscope (0/30/45 degrees) of diameter 4mm and length 20 cms. 2. Septal Elevator with a flat tip of 4mm 3. Ball probe with a rounded tip of diameter 1-2.5mm Safety Constraints 1. The tip of the balloon catheter should be larger than the isthmus (> 1mm in diameter) and atraumatic to avoid entry into the bony portion of the ET (which is in the skull base) 2. The balloon should be soft enough to not cause any damage to the mucosal lining during insertion of the catheter into the ET 3. The instrument should provide feedback about the length of the catheter entering the ET with the help of markers etc.

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Other product constraints 1. The guide should be rigid so as to allow the flexible balloon catheter to reach the opening of the ET easily. 2. The guide should be angled at 55 degrees for easy insertion into the ET. (AC 5) 3. The guide should have a softer/atraumatic tip with a max diameter of 4 mm. 4. The balloon should be of maximum length 22 mm and maximum diameter of 6mm (AC 1 & 4) 5. The tip of the balloon catheter should be rounded and of a diameter >1 mm to avoid entry into the bony part of the isthmus. 6. The balloon should inflate with a pressure of 12 atm at least 4 times before being disposed. 7. The guide should be sterilizable (ETO / Autoclave) 8. The guide should be ergonomic or the doctor to use along with the other instruments in the nasal cavity. 9. All parts of the product should be made of biocompatible materials 10. The material of the balloon should allow a coating of anaesthesia (lidocaine) 11. The manifold of the balloon catheter should be compatible with the valve of the inflation system. 12. The guide should be a minimum of 16-18cms long depending on the hands of the surgeon.

Filling the inner surface of the 55Â° guide

Phase Four 97

Careflow A careflow is the experience of a patient getting diagnosed and treated for a particular problem. The careflow for Eustachian Tube Dysfunction was identified and made on the basis of the medical management chart on pg 46-47. All stakeholders at each step involved were identified and listed. This helped assess how they were impacted and how that changed after the intervention was introducted. The careflow on the right is based on current methods of treatment and diagnosis. Stakeholders corresponding to each step of the careflow (pg. 99) are listed on the left.

List of Stakeholders at every step Patients General Physician, Pediatrician Receptionist/ Compounder/ Cashier, Clinic Manufacturers of medication/ Drug Companies Pharmacy Patient's Family

ENT Specialist, Clinic, Hospital, OPD, nurses Administrative Staff, Receptionist, Cashier Manufacturers of endoscopes/ head lamps Radiologist, Audiologist, Diagnostic Center, Audiologist Center

Pharmacy, Insurance Company Administrative Staff, Receptionist, Cashier Patient's family, nurses, doctors, Radiologist, Audiologist ENT specialist, Cleaning Staff, Sterilisation services, Anaesthesiologist, Manufacturers of Sterilisation Packing, Drug Companies who manufacture Anaesthesia, Manufacturers of surgical equipent, Manufacturers of packing material, Medical waste management staff, Collectors of medical waste, Nurses, Junior Doctors, Purchase Department, Biomedical Engineering Department, OT technicians/ OT nurses Cleaning staff, Nurses, Junior Doctors, Patient's Family, Food vendors Hospital/clinic, Administrative staff, Insurance Company Patient's family

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Patient has symptoms like ear pain, blocked feeling, muffled hearing. If age<12

Patient goes to a Pediatrician

If age>12

Patient goes to the General Physician

Patient pays the Consultation fee to the Receptionist/Cashier. Doctor prescribes decongestants and/or antibiotics. Patient/ Patient's family goes to the Pharmacy to purchase medication. The patient goes Home and takes the course for a few days. If the patient feels better after the course of medication, he/ she continues with his/her day to day activities.

If the patient doesn't feel better after the course of medication or if the symptoms return Patient goes to consult an ENT doctor at a hospital or a clinic. Patient pays the Consultation fee. ENT doctor inspects the ear with a scope/head lamp and asks for scans/audiometry results/tympanometry results. Patient goes to radiology/audiometry and gets scanned. (if required) Patient waits and collects scans. Patient comes back to ENT specialists with test results. ENT specialist looks at tests and prescribes required medication/ counsels for procedure.

If the patient has to take a course of medication, he/she goes to the Pharmacy to purchase medication. The patient goes Home and takes the course for a few days. If the patient feels better after the course of medication, he/ she continues with his/her day to day activities.

If the patient has to undergo a procedure/ surgery (Myringotomy or Tympanoplasty) A date and time is decided for the procedure. Patient pays bills and consultation fees at the reception. The patient comes back at the required time and gets the pre surgery workup done. The patient comes back at the required time and undergos the procedure/surgery in the OT/ENT Procedure Room under a local/ general anaesthesia administered by an anaesthesiologist. Patient stays in the hospital for the required watch time and is taken care of by nurses and junior doctors. Patient pays remaining fees at the reception. Patient goes home. Comes back for a follow up check within the required period of time.

Phase Four 99

Competitor Analysis There are a few products in the west that are built to perform Balloon Eustachian Tuboplasty (BET). These systems are unavailable for use in India and are very expensive. The main competitors are: 1) Acclarent Aera (USA) The Aera is most well known BET instrument. It is very expensive and no part of it is reusable.

Source - Acclarent

2) Spiggle and Theis - TubaVent (Germany) This is the oldest instrument in the market, but has the smallest working diameter and no part of the system can be reused.

Source - Spiggle and Theis

3) Entellus xpressENT (USA) This is a versatile tool that lets the user change the bend angle as required to work for the three sinuses and the Eustachian Tube.

Source - Entellus

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The table on the right comparatively analyses all the products in the market that can perform Balloon Eustachian Tuboplasty (BET) including those whose primary purpose is something else and could be used for BET as an affordance.

Phase Four 101

About Balloon Tuboplasty Developed in the late 1970s, high-pressure balloons have traditionally been used in angioplasty, a procedure that opens blood vessels clogged by built-up, fatty plaque. The balloon, tightly wrapped around a catheter shaft to minimize its profile, is inserted through the skin and into the narrowed section of the vessel. Inflating the balloon, typically with a radiopaque solution or saline forced through a syringe, exerts high pressure, which compresses the plaque against the wall of the vessel and allows the blood to flow normally. For retraction, a vacuum is pulled through the balloon to collapse it. The procedure was developed as a less invasive and less costly alternative to coronary bypass, a complex surgical procedure that skirts the blockage by grafting a section of vein, typically taken from the leg, to locations above and below the afflicted area.

Inflating the balloon with saline forced through a syringe, exerts high pressure, which compresses the plaque against the wall of the vessel and allows the blood to flow normally.

Angioplasty: Balloon Dilation of the coronary artery Source - Pinterest

Today high-pressure balloons, with thinner walls, higher strength, and smaller profiles, are well suited for use in a broad range of minimally invasive procedures. They can be produced in a wide range of diameters, lengths, and shapes, including complex custom shapes for specific applications and specialty coatings for added performance. Enhancements in balloon design and technology have provided increased flexibility to designers of medical devices, making the development of new and improved devices possible. As a result, high-pressure balloons are used in a variety of therapeutic procedures like stent and drug delivery catheters.

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High-pressure balloons, with thinner walls, higher strength, and smaller profiles, are well suited for use in a broad range of minimally invasive procedures.

BET Prototyping Balloon Eustachian Tuboplasty involves the insertion of a balloon catheter into the Eustachian Tube with the help of a guide, inflating the balloon and dilating the cartilaginous portion of the Eustachian Tube with a pressure of 10 atmospheres. The tool to be made would comprise of a balloon catheter and a guide that would help it reach to the Eustachian Tube from the nasopharyngeal opening. The angle of the eustachian tube from this opening was determined to be approximately 55 degrees (confirmed in the cadaver study). The length of the guide was ascertained roughly on the basis of the SinuCare guide and other tools (like ball probes, septal elevators) used in the nose.

The tool to be made would comprise of a balloon catheter and a guide that would help it reach to the Eustachian Tube from the nasopharyngeal opening.

The Guide A 55 degree guide was 3D modelled and polyjet printed in plastic and bent and cut in a metal tube, for the cadaver study. It was observed that this tube blocked the entrance of the ET didnâ&#x20AC;&#x2122;t allow visualisation as the balloon entered the Eustachian Tube. The doctor would not know how much to push and where the balloon ends if they wouldnâ&#x20AC;&#x2122;t be able to see it enter. To tackle this, a diagonal cut was made at the tip of the 55 degree tube.

55 degree guide for cadaver study

Sinucare balloon in 55 degree guide (diagonal tip)

55 degree guide with diagonal cut

Phase Four 103

The Balloon Catheter A balloon catheter comprises of: 1. an inflatable balloon, 2. a tube/shaft and 3. a manifold/luer which gets connected to an inflation system/syringe All high-pressure balloons are fabricated by first extruding a tube, cross-linking the extrusion if required, then reheating and stretch blow molding the extrusion into the desired geometry. A standard dilatation balloon consists of a cylindrical body, two conical tapers, and two necks (proximal and distal). Thus manufacturing/ prototyping a high pressure balloon requires a lot of expertise and machinery and cannot be made in small setups.

Various balloon samples and prototypes of SinuCare balloons were used to prototype the required balloon. SinuCare is a double balloon catheter i.e. it has a distil and a proximal balloon. The distil balloon (at the tip) is a low pressure, small, soft and spherical balloon and the proximal balloon is a high pressure balloon that can take pressure upto 12 atm. This is required to fracture the bony ostium of sinuses. To cause a crush injury in the cartilaginous ET, this high pressure proximal balloon was perfect. Thus, SinuCare balloon catheters were adapted for use in the Eustachian Tube by carefully cutting of the distil balloon. SinuCare balloons have double tubing. The inner tube connects to the distil balloon and the outer tube connects to the proximal balloon. The inner lumen is fused to the outer lumen at the junction between the distil and proximal balloon. When the distil balloon is cut off, the proximal balloon continues to function perfectly because of this fused end. To ensure safety of the isthmus and the soft cartilage, this exposed tip/junction of the balloon catheter was rounded off neatly with a scalpel.

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Thus manufacturing a high pressure balloon requires a lot of expertise and machinery and cannot be made in small setups.

A standard balloon

To cause a crush injury in the cartilaginous ET, the high pressure proximal balloon of SinuCare was perfect.

SinuCare distil balloon inflated

SinuCare distil balloon cut off

SinuCare proximal balloon tip rounded

The manifold is the part that connects the balloon catheter to an inflation system. SinuCareâ&#x20AC;&#x2122;s balloon catheter has a dual port manifold. The two different ports connect to the two balloons. The distil balloon (the soft round balloon at the tip) is connected through the straight port and the proximal balloon (the long high pressure balloon) is connected through the diagonal port. After the distil balloon was cut off, the horizontal port didnâ&#x20AC;&#x2122;t have a purpose. For a looks-like prototype, the manifold was adapted and the diagonal port was cut off to make it look like a vertical, straight port. For a works-like prototype, the manifold was retained.

Adapted Manifold

Prototyping the Manifold for the Catheter

Phase Four 105

Sterilisation Methods Sterilisation refers to any process that eliminates, removes, kills, or deactivates all forms of life and other biological agents present in a specified region, such as a surface, a volume of fluid or medication. Sterilisation can be achieved through various means, including: heat, chemicals, irradiation, high pressure, and filtration. It is important to know about these when creating surgical equipment because all surgical tools that touch/enter the human body must be sterile to avoid infection. The tools need to be designed keeping in mind that they must be sterilised using one of these methods. The common methods of sterilising medical equipment are: 1. Steam Autoclave - An autoclave is a pressure chamber that is used to sterilise equipment and supplies. When these items are placed inside the autoclave they are exposed to high temperature steam (usually around 132 degrees Celsius or 270 degrees Fahrenheit) for about twenty minutes. 2. ETO (ethylene oxide) - Ethylene oxide sterilization is a chemical process consisting of four primary variables: gas concentration, humidity, temperature and time. EO is an alkylating agent that disrupts the DNA of microorganisms, which prevents them from reproducing. This method is used to sterilise SinuCare equipment. 3. Gamma Radiation - The gamma sterilization process uses Cobalt 60 radiation to kill microorganisms on a variety of different products. It easily penetrating packaging and product, and is ideal for many types of materials. 4. UV Radiation - Ultraviolet germicidal irradiation (UVGI) is a disinfection method that uses short-wavelength ultraviolet (UV-C) light to kill or inactivate microorganisms by destroying nucleic acids and disrupting their DNA, leaving them unable to perform vital cellular functions.

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ETO Sterilisation Source - SteriPack

Phase Four 107

Clinical Study A clinical study was conducted to check BETD as a technique and to see how a prototype would perform in a living person. This was done to get feedback and to help improve the tool. A consent form, a working prototype and study questions were created for this purpose. Feedback about the tool was taken.

Consent Form A consent form was created for the patient. It included details about the procedure, the tool being used, aims of the study, potential risks and benefits and medicolegal details telling the patient about voluntary participation. This form can be found in the appendix

About the Patient The patient had been suffering with bilateral chronic Eustachian Tube Dysfunction for a few years. He had severe DNS with spurs and enlarged turbinates. He underwent surgery for correction of DNS, turbinate reduction, removal of spurs and bilateral Balloon Eustachian Tuboplasty at Apollo Spectra, Delhi on 24th July. He had done a tympanometry one month before the procedure in Bangalore and was prescribed another tympanometry 4 weeks post procedure. Nasal packs were removed 48 hours after the procedure and the crusts were cleaned out, a basic endoscopy was done.

The Tool Guide A 55 degree metal guide with a diagonal cut at the tip was used to guide the balloon catheter to the opening of the Eustachian Tube in the nasopharynx. The guide had a cross sectional diameter of 4 mm and the length 14 mm. The radius at the 55 degree at the bend is 6 mm. This was ETO sterilised. Balloon Catheter The SinuCare double balloon catheter was altered to be used in the Eustachian Tube of the patient. The distill balloon was cut off and the tip of the proximal balloon was neatly rounded to be used as an atraumatic tip to avoid entry into the bony isthmus. The working length of the Sinucare balloon is 18 mm and the working diameter of 6 mm.

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A clinical study was conducted to check BETD, to see how the prototype would perform and get feedback.

Study Questions Was the 55 degree angle suitable to access ET opening? Did the guide have to be tilted to access the opening? Yes, No tilting was required, the tool was rotated in the choana to access the opening of the Eustachian Tube.

How many inflations did the balloon allow? Did the second balloon have to be used? Only 1 balloon was used which was still okay after 12 balloon inflations

Was there any damage caused to the tissue at the opening because of the diagonal cut tip of the guide? No damage was caused to the tissue by the guide.

Was there any tactile feedback when you approached the isthmus? Were you able to tell the bone apart from the tissue when probing with the tip of the balloon? There was tactile feedback, the doctor could feel the isthmus when the balloon tip touched it

Were you able to see the balloon entering the Eustachian Tube? Yes If you had to estimate the size of the opening with the help of the eustachian tube guide, how big do you think it is? 50-60% of the guide

Was any damage caused to the bony part of the ET? Were there any tears in the wall of the ET? No damage to either

How much did it enlarge when the patient swallowed? Patient was under General Anaesthesia, no swallowing

Was the patient swallowing during inflation, did the ET tube expand by itself? Patient was under GA, didnâ&#x20AC;&#x2122;t swallow

How long was it required to keep the tool in to ensure dilation? Left - 5 minutes, Right - 3 minutes

Were there any bleeders? Where was the blood originating from? No bleeding from the Eustachian Tube was observed

How many times did you have to dilate the ET on both sides? 6 times on both sides at varying pressures.

What kind of packing was used to contain the bleeding? Dylot adrenaline gauze

Phase Four 109 A screenshot from the endosccopic visualisation of the surgery: Guide entering ET

Dr. Jagdish performing BET on the patient

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Patient’s Progress The patient is a singer. Before the surgery, he felt like his eardrum was interfering with his quality of hearing. A tympanometry was done a month before his surgery to assess his eardrums. After the surgery, the patient felt immediate relief and said that the pain, muffled hearing were no longer present. He had crusting in his nasal passageways which was removed using nasal sprays. About two weeks after the surgery, the patient had a performance. He said that his vocals and nasal passageways cooperated during the event and he could feel significant improvement. A tympanometry was done 3 months post operatively. This was assessed by Dr. Jagdish Chaturvedi. He said that when the two tympanometry reports are compared, it can be seen that there has been improvement in the ear drum compliance and middle ear pressure. But it has not come back fully to normal. The two tympanometries can be found in the Appendix for reference.

Feedback from Tool •

Doctor needs to be able to push the balloon out while holding the guide and the endoscope in the required position.

•

70 degree scope is difficult to use for visualisation of the Eustachian Tube.

•

The balloon needs to be retracted from the Eustachian Tube and into the guide with ease.

The Doctor needs to be able to actuate and retract the balloon catheter while holding the guide and the endoscope in the required position.

Phase Four 111

Addressing the Gaps The Gaps Since both Eustachian Tuboplasty and Balloon Sinuplasty require surgery through the nose, SinuCare usage was studied to understand how the tool could be designed. After observing balloon sinuplasty surgeries and seeing it being used in a headmodel, gaps in the usage were identified. â&#x20AC;˘

The doctor uses one hand to position the guide and one to hold the endoscope in place, which means he has to rely on a third person (nurse/doctor) to push the balloon through the guide. This may compromise the safety of the patient.

â&#x20AC;˘

Sometimes while using the balloon system, the doctor inflates the balloon while itâ&#x20AC;&#x2122;s still inside the guide.

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A need for a single handed actuating balloon catheter with indicators or a tactile method of stopping the balloon from being inflated while inside the guide, was pointed out.

Ideating Solutions Different ways of solving these problems were thought of, they are documented in sketches. The sketch on the right shows a concept for a balloon catheter guide in which retraction of the catheter works on the same principle as that of a paper cutter,

Phase Four 113

Currently, It is hard to tell the Balloon from the shaft of the catheter because its profile is made such that it easily fits into any opening and then expands. Marker bands on the shaft of the balloon serve as visual indicators to tell the doctor that the entire body of the balloon has come out of the guide. It was observed during surgery that doctors didnâ&#x20AC;&#x2122;t follow this visual indicator accurately and ended up inflating the balloon while it was still inside the guide. This damages the balloon and reduces its life. The idea on the right discusses a method of blocking the inflation port till the balloon comes all the way out of the guide.

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The length of a standard balloon is usually much longer than that of the guide. The idea was to limit the length of the balloon and allow the doctor to use the manifold not just to inflate the balloon but also to push it out. The sketches above have different forms for the manifold to assist the pushability of the balloon.

Phase Four 115

Ideating Solutions Another way of avoiding the balloon from being inflated while inside the guide was thought of. The sketch below shows a concept for a catheter with a manifold with a wing and a guide with a slit. The fixed length would make it easy for the doctor to actuate the catheter.

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Prototyping A balloon catheter was made by cutting a SinuCare balloon from the middlle and heatshrinking the plastic lumen. This prototype was made to check the pushability of the catheter by the manifold through the guide.

Balloon Catheter made using parts of SinuCare

Pushing the balloon catheter into the guide

Only the balloon comes out from the tip of the guide

Phase Four 117

Grips It was realised that the doctor would need support around the metal guide to grip it and hold it in place. A few types of grips were made and tested with Dr. Jagdish Chaturvedi in a benchmodel. A simple straight support was selected. It was observed to be easiest to maneuver. The others seemed bulky and restrictive.

Dr. Jagdish tested the variety of guide grips.

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Anthropometry & Ergonomics Length of the Nasal Cavity The length of the nasal cavity from the apex of the nose till the Eustachian Tube would ascertain the length of the balloon catheter and the guide. This was found out by various means, by measuring CT scans, human cadavers and by measuring existing tools that were inserted into the nasal cavity. The average length was found to be 8 cms. This determined the measurements of the tool.

ET Diameter The diameter of the cartilaginous part of the Eustachian Tube was measured in a human cadaver to be around 3 mm when collapsed and upto 6 mm when expanded.

Finger Span To use an actuating catheter in the nasal cavity, it was important to ensure that the length of the tool extended well beyond the nasal cavity. It was also to be checked if the surgeon was able to hold the guide in a stable manner using his/her thumb and middle finger and retract the manifold using his/ her index finger. Thus the length that the index finger could extend itself away from a pinched thumb and middle finger was a necessary parameter. This was checked in an ergonomics study.

Phase Four 119

Ergonomics Study Manifold grips were made in a variety of forms and tested in a headmodel by people of both genders and differing sizes of hands. This was done to help decide the dimensions of the final tool and to check how ergonomic each manifold was. Hand spans, preferences of all the participants were noted. These grip manifolds were moulded using mseal and made such that they would easily slip on to a balloon catheter shaft. Each participant was given a nasal insert with a marked eustachian tube and a balloon catheter loaded in the guide with the balloon just at the tip of the guide. The participant was asked to push the balloon and retract it with every manifold. The participant had to then rate the manifolds in order of preference. Each person was observed carefully.

Custom made push manifolds to test pushability of the balloon catheter

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User Testing of the push manifolds

Phase Four 121

Checking ergonomics of the various push manifolds

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A table was made to compare all the participants on the basis of their measurements and preferences. The most commonly preferred choice of manifold was the large disk manifold. It was observed that the participants used it with ease, both to push the balloon in and to retract it. The ring was the second preferred choice but it wasnâ&#x20AC;&#x2122;t selected because it was observed that it worked only when the catheter was positioned in an accessible direction. It didnâ&#x20AC;&#x2122;t allow 360 degree access. Hence the disk manifold was selected and worked on further. The finger span gave a good idea about the measurement of the final tool to make it such that it could be used single handedly.

The preferred choice of manifold was the large disk manifold.

Phase Four 123

Sketches showing calculations done to determine the length

Calculating the Final Dimensions The final dimensions were worked out on the basis of the anthropometric measures and the ergonomics study. The different parts were then 3D modelled and assembled.

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Product Specifications This is a single handed balloon assisted system used to treat Eustachian Tube Dysfunction by dilating the cartilaginous portion of the Eustachian Tube, relieving middle ear pressure and draining any mucous trapped within. This system is designed for in-office use, under local anaesthesia, during a nasal examination (endoscopy) or under GA in an OT for more advanced cases. The system works with a standard endoscope (30/45 degree), and its guiding tube allows the ENT surgeon to guide the balloon into the Eustachian Tube opening in the nasopharynx to dilate and unclog the Eustachian Tube.

Parts of the Product The Guide A 55 degree metal guide with is used to guide the balloon catheter to the opening of the Eustachian Tube in the nasopharynx. It has a diagonal cut at the tip which allows the doctor to see the balloon enter the eustachian tube clearly. The guide has a cross sectional diameter of 4 mm and the length and the grip are TBD. The radius at the bend is 6 mm. It also has a grip made out of silicone at the proximal end. It helps the doctor grip it and hold it in place with ease without having it slip. The Balloon Catheter The balloon catheter is designed to be inserted and inflated in the cartilaginous portion of the Eustachian Tube. It consists of a dilation balloon of length < 20 cms due to anatomical constraints, a rounded atraumatic tip for feedback and to avoid entry into the bony ishthmus. It also has an inner lumen with a skive hole onto which the balloon is bonded and allows entry of saline to expand the balloon. There is an outer stiff shaft which allows easy pushability into the guide. There is a critical gap between the inner lumen and the outer shaft that allows it to take the 55 degree turn in the guide (Trackability). The whole system is connected to a manifold which has a disk for pushing and retracting the balloon out of the guide and a luer that allows it to be connected to an inflation system or a syringe that inflates the balloon. The balloon catheter is intended for single patient use only and will be in contact with mucosal fluids.

Phase Four 125

1 F

Outer shaft length - 140 mm Inner lumen length -173 mm

12 mm Critical gap between proximal bond of balloon and outer shaft

2 6

48°

66°

ITEM NO.

DESCRIPTION

Rounded tip for inner lumen

Dilation Balloon

Inner Lumen

Outer Stiff Shaft

Manifold

Marker ring

DIMENSIONS ARE IN MILLIMETERS (mm)

DETAIL A SCALE 4 : 1

NAME DRAWN

Gaurika S

DEBURR AND BREAK SHARP EDGES

FINISH:

SIGNATURE

DATE

DO NOT SCALE DRAWING

REVISION

TITLE:

ET Balloon Assembly

9/7/2017

CHK'D APPV'D MFG

Q.A

MATERIAL:

DWG NO.

WEIGHT:

SCALE:2:1

A3 SHEET 1 OF 1

Technical Drawings Technical Drawings of the Balloon Catheter and 55 degree Guide were made.These assisted in the making of the technical specifications. They were sent to manufacturers to get quotations.

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55Â°

3.80

148.5

4.50 3.80

7.60 3.60

16.8

E 2

B UNLESS OTHERWISE SPECIFIED: DIMENSIONS ARE IN MILLIMETERS SURFACE FINISH: TOLERANCES: LINEAR: ANGULAR: NAME DRAWN

DEBURR AND BREAK SHARP EDGES

FINISH:

SIGNATURE

Part Grip 55 degree tube

DATE

Material Silicone/ Rubber SS 304

DO NOT SCALE DRAWING

1 2

REVISION

TITLE:

Gaurika S

CHK'D

APPV'D

MFG MATERIAL:

Q.A

WEIGHT:

DWG NO.

Guide with grip 55 deg SCALE:1:2

SHEET 1 OF 1

UNLESS OTHERWISE SPECIFIED: DIMENSIONS ARE IN MILLIMETERS SURFACE FINISH: TOLERANCES: LINEAR: ANGULAR: NAME

DRAWN

DEBURR AND BREAK SHARP EDGES

FINISH:

SIGNATURE

DATE

DO NOT SCALE DRAWING

REVISION

TITLE:

Gaurika S

CHK'D

A custom made push manifold was also 3D modelled. It was made such that it would act as an inflation port and as an actuator of the balloon catheter, to push it in and retract it out of the guide.

APPV'D

MFG Q.A

MATERIAL:

DWG NO.

WEIGHT:

SCALE:2:1

Push Manifold 2

SHEET 1 OF 1

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Technical Specifications Technical Specifications for the final balloon catheter were made. These were to be sent to potential manufacturers to understand limitations, possibilities and cost. Creating these specifications required a good understanding of balloon engineering and manufacturing processes and of tolerances. This process took a few days. The final Balloon Technical Specification Document can be found in the appendix. Assembled Balloon System • Trackability - through 55 degree guide as per drawing. • This will be a Class I device as per CE certification • Should be sterilised by ETO protocol prior to supply (6 months shelf life minimum) - 6 months shelf life - extended to 2 years as testing is completed • No separate guidewire channel • Single standard skeeve to be included within the balloon - preferably within 5 mm of the proximal bond of the balloon Dilation Balloon (refer to drawings) • Maximum Balloon Profile should not exceed 2.5 mm in deflated state • Balloon should be transparent • Single Patient Use (Bilateral) • Average Burst Pressure of 12 atm • Rated Burst Pressure of 10 atm (RBP) • Working length of 16 mm • Cone angles TBD (Refer to drawing) • Total balloon length should not be > 20 mm (cone to cone) • Dilated diameter of 6mm along the working length at pressure of 10 atm • Minimum of 4 RBP inflations after passing through the guide* with 2 minutes hold time each • Maximum inflation hold time > 10 minutes • The balloon should be made of suitable biocompatible material for transient use with mucosal contact (Possible materials for balloon include Pebax, Nylon 12, PET) • Assumed bond length of 2 mm (Folding pleats TBD Bifold or Trifold should suffice) Inner Lumen • Tip entry profile should be smooth and rounded with a crosssection diameter >1 mm and <2mm and be bonded to the inner lumen (lumen can be heat shaped with a tipping machine or a separate bonded piece. In either case, sealed end.)

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• • •

• • • • •

Projection of tip beyond distil bond of balloon should not exceed 1 mm (Assumption of tipping done prior to balloon bonding) The inner lumen should be opaque/ transluscent (preferable colour blue) Radioluscent marker band at 24 mm from distil tip of dilating balloon. Should be of a contrasting colour to the inner lumen. (Overlapping with proximal balloon bond. Can be pad printed or heat shrink tubing. Assumption of marker put before balloon bonding.) The ID should be 0.8mm (Tolerance of 0.2 mm) OD should be 1.2 mm (Tolerance of 0.2 mm) Total length - 173.2 mm (accounting 1.2 mm for the rounded tip) The inner lumen should be made of suitable biocompatible material for transient use with mucosal contact. (Possible materials for balloon include Pebax, Nylon 12, PET.) Trackability is key.

Outer Stiff Shaft • The outer shaft can be opaque (Can be same colour palette as inner lumen) • ID - 1.2 mm (Tolerance of only +0.2 mm) • OD <2.5 mm (Based on pushability and stiffness user requirements) • The outer lumen should be stiff and act as a • strain relief (Shore hardness (D) between 60 to 80 TBD) • Total length - 140 mm • The outer shaft should be made of suitable biocompatible material for transient use with mucosal contact. (Possible materials include Pebax, Nylon 12, PET. Pushability is key.) Push Manifold • Manifold requires only one inflation port • Port should be compatible with standard luer locks and syringes • Specific design for custom manifold TBD )For POC, off the shelf manifold is sufficient)

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EustaCare EustaCare is a Balloon Eustachian Tuboplasty Tool. It is an affordable, minimally invasive instrument that helps treat patients suffering with chronic ETD.

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55 degree metal guide

Inner lumen Inflatable Balloon

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Outer Shaft

Silicone grip

Push Manifold

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Push Manifold

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Assembly of the Balloon Catheter in the Guide

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CONCLUSION This section discusses the development pathways that the company could take while taking this project forward and my reflections about this project.

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Concluding Comments EustaCare was made ready for manufacturing with the exception of any iterations that would be required after the first round of usability testing. On the basis of the clinical trial, research papers and multiple cadaver studies, it was clear that the tool would work. A primary level risk management analysis was done to ascertain if all the problem areas had been addressed and on the basis of SinuCareâ&#x20AC;&#x2122;s performance a few assumptions were made about the performance of EustaCare. The product specifications were sent to manufacturers, materials for the balloon catheter were finalised.and the cost was worked out. This was a sum total of the assembly development budget, cost per piece and custom duty. It was worked out that at higher volumes, the cost of the product to patient would be well within 8000 Rs.

Credits - Calvin & Hobbes by Bill Watterson

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Looking Forward Six months is an impractical limitation for a project in the field of Biodesign. A surgical equipment like Eustacare ideally requires a two year timeline, for development, manufacturing, getting medical certifications and implementation. Eustacare needs more usability testing to check whether or not it requires another iteration. But to test the usability, a prototype of the exact functionality, dimensions and weight is needed. Balloon manufacturing has to be done in bulk. To make a balloon catheter of the exact specifications, an extrusion mould would have to be created and the cost for getting the mould made for a few pieces is too high. The company had a few development pathways for this project. One possibility is to go ahead with EustaCareâ&#x20AC;&#x2122;s blind balloon dilation system (visualisation only until the opening of the Eustachian Tube). Since EustaCare has been made ready for manufacturing, the timeline to market for this pathway would be about 8 months. The Development cost for the company could also be easily determined on the basis of the costing received from the manufacturer. The other possibility is to integrate the visualisation system being developed alongside, with this balloon dilation system. This would be something like a steerable balloon dilator with a camera at the tip. The timeline to market for this concept would be 12-18 months and the development cost of this is unknown. The company hopes to finalise an approach and get this project into market by the end of 2018. I am looking forward to seeing EustaCare benefitting patients and improving their quality of life..

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Reflections On looking back, I can easily say that this graduation project was one of the most complex projects that I have attempted. It was a journey with many detours and challenges and therefore it taught me many things. I realised that design thinking helps in connecting the dots between the emerging technology, current trends, medical know-how and the right need. Additionally, it helps to empathise with people and understand the problem. With a growing population, the need for frugal innovation in healthcare is pressing in India. The use of innovative design thinking and strategies can be a big contributor to creating more efficient healthcare products, continuous improvement in quality, and lower total cost.

The use of innovative design thinking and strategies can be a big contributor to creating more efficient healthcare products, continuous improvement in quality, and lower total cost.

While working at Innaccel, I was a significant contributor with the opportunity to work on more than just my project. I got an environment to learn and teach the Biodesign process, help with making usability guidelines for the company, learn about IP, medical product compliance standards and various surgical equipments and techniques. I had a sense of responsibility and ownership towards my project and at the same time I was able to work with a diverse team that helped create a meaningful outcome.

I had a sense of responsibility and ownership towards my project and at the same time I was able to work with a diverse team that helped create a meaningful outcome.

With just a morsel of pride, I can say that I was able to learn a lot about an unknown field, anatomy and physiology, in very little time. I gained the confidence to speak the medical language, approach experienced doctors and converse with them about the same.

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As a student of Industrial Design, I have always hoped to create a product that would eventually benefit someone. I had the privilege of working on a project that had the ability to help someone get better. I was lucky to experience the thrill of my prototype being used on a live human being and the patient benefitting from it.

I had the privilege of working on a project that had the ability to help someone get better.

This project offered me excellent exposure in Biodesign and Healthcare Innovation. I was able to observe the functioning of a startup and gain a lot of knowledge about the entire process right from need finding to development to delivery. Designing a product for manufacturing was an enriching experience as it taught me the difference that a few millimetres can make to the final product. I learnt to work with many constraints (human body) and to value precise and careful documentation. I became more aware about biocompatible materials and how tiny changes affect the overall cost of the product. By the end of the project I was able to appreciate anatomy, the human body, the science of medicine and the work that doctors do.

I learnt to work with many constraints (human body) and to value precise and careful documentation.

The Biodesign process taught me to make quick, unbiased observations and deriving need statements from them. I know now that Observations enhance the scope and magnify your experience. Opportunities and exposure increase your absorption and acclimatize you to a new area. They also give you the confidence to enter new arenas, a boost which is not possible if you stay in your comfort zone. Even if I donâ&#x20AC;&#x2122;t continue to work in this sector, I will always value and use the learnings that I have gotten from this project. I am excited about what lies ahead.

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GLOSSARY

BALLOON LENGTH typically refers to the working length or the length of the straight body section

CLASS I Classification of a medical device by the FDA that indicates low risk to a person.

ACUTE SUPPORATIVE OTITIS MEDIA (ASOM for short) It is Otitis Media that discharges through a perforated tympanic membrane (eardrum). see Otitis Media

BALLOON PROFILE maximum diameter of the balloon when mounted on a catheter in its deflated and wrapped condition or the smallest hole through which the deflated wrapped balloon catheter can pass

CLASS II Classification of a medical device by the FDA that indicates intermediate risk to a person. Class II devices are typically more complex than class I devices but are usually non-invasive.

ADENOID It is a soft mound of lymphatic tissue in the nasopharynx. They are also known as Nasopharyngeal Tonsils. ADHESION The action or process of two surfaces sticking together. ANATOMY The branch of science concerned with the bodily structure of humans, animals, and other living organisms, especially as revealed by dissection and the separation of parts. ANTERIOR RHINOSCOPY Itâ&#x20AC;&#x2122;s an examination of the nose from the outside using a Rhinoscope AURAL relating to the ear or the sense of hearing BALLOON BURST PRESSURE average pressure required to rupture a balloon; usually measured at body temperature BALLOON COMPLIANCE change in balloon diameter as a function of inflation pressure BALLOON DIAMETER nominal inflated balloon diameter measured at a specified pressure

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BALLOON RATED BURST PRESSURE maximum statistically guaranteed pressure to which a balloon can be inflated without failing. For PTCA and PTA catheters, this is normally 95% confidence/99.9% guarantee BENCH TESTING Testing prototypes (materials, methods, functionality) in a controlled laboratory environment (not in animals or humans). BIOCOMPATIBILITY The property of a material that indicates that it is suitable to be placed in humans. CATHETER A catheter is a thin tube made from medical grade material used for a variety of functions mostly to treat or perform a surgical procedure. Functionally, they allow drainage, administration of fluids or gases and access by surgical instruments, and also perform a wide variety of other tasks depending on the type of catheter. CATHETERISATION The process of inserting a catheter in a body cavity is called catheterisation.

CLASS III Classification of a medical device by the FDA that indicates the highest risk to a person. Class III devices are typically invasive or life sustaining. CLINICAL OBSERVERSHIP/ SHADOWING Observing a healthcare professional provide care to patients or clients in a clinical setting, such as a hospital, clinic etc. One gets to see what the day-to-day responsibilities of a health care giver might involve within a healthcare setting. CLINICAL PROTOCOL A study plan on which all clinical trials are based. The plan is carefully designed to safeguard the health of the participants, as well as to answer specific research questions. A protocol describes what types of people may participate in the trial; the schedule of tests, procedures, medications, and dosages; and the length of the study. CLINICAL TRIAL A research study performed to answer specific questions about diagnoses or therapies, including devices, or new ways of using known treatments.

Clinical trials are used to determine whether new treatments are both safe and effective. CHOLESTEATOMA is a destructive and expanding growth consisting of squamous epithelium in the middle ear and/or mastoid process. CHRONIC SUPPURATIVE OTITIS MEDIA (CSOM) is Otitis Media that discharges through a perforated tympanic membrane (eardrum) for at least six weeks. CYCLE OF CARE A description of how a patient interacts with the medical system. DECONGESTANT is a type of pharmaceutical drug that is used to relieve nasal congestion in the upper respiratory tract DESIGN CONTROLS One subsystem of a quality management system. Controls that ensure the device being designed will perform as intended when produced for commercial distribution. DESIGN VALIDATION Ensuring that a design does what it intends to do DESIGN VERIFICATION Ensuring that a design meets product specifications. DEVIATED NASAL SEPTUM Sideways displacement of the wall between the nostrils. ENDOSCOPE An instrument which can be introduced into the body to

give a view of its internal parts. ENDOSCOPY The act of introducing an endoscope into the body. EPIDEMIOLOGY Study of factors affecting the health and illness of a population that are used as the basis of making interventions in the interest of public health. EUSTACHIAN TUBE also known as the auditory tube or pharyngotympanic tube, is a tube that links the nasopharynx to the middle ear. EUSTACHIAN TUBE CATHETER The Eustachian Tube catheter is a long, thin metal instrument mainly used to flush the ET with air or water to help remove obstructions (like mucous) and to equalise middle ear pressure. EUSTACHIAN TUBE DYSFUNCTION (ETD) refers to the impaired function of the Eustachian Tube ie. the Eustachian Tube is unable to clear the mucous from the middle ear into the nasopharynx and stabilise the pressure. EVIDENCE BASED Treatments, guidelines, and processes based on the results and outcomes generated from experiments and observation, which use specific evidence of outcomes and suggest treatment or processes based on such evidence .FESS (FUNCTIONAL ENDOSCOPIC SINUS SURGERY) It is a surgical treatment of sinusitis and nasal

polyps, including bacterial, fungal, recurrent acute, and chronic sinus problems. FESS uses nasal endoscopes to restore drainage of the paranasal sinuses and ventilation of the nasal cavity. FIBROSIS The thickening and scarring of connective tissue, usually as a result of injury FIBROTIC BANDS Scarred tissue bands on the mucous membrane FLOW OF MONEY Analysis, aimed at identifying key stakeholders, that is focused on payments to providers of healthcare services. FREEDOM TO OPERATE The ability to commercialize a product, without infringing on the intellectual property rights of others. GROMMET A tube that is surgically implanted in the eardrum to drain fluid from the middle ear HEADMODEL A model of a human head for benchtop testing or for practice HYPERTROPHY It is the increase in the volume of an organ or tissue due to the enlargement of its component cells. HYPOTHESIS A supposition or assumption advanced as a basis for reasoning or argument, or as a guide to experimental investigation. IDEOPATHIC Relating to or denoting any disease or condition

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which arises spontaneously or for which the cause is unknown. IFU (INDICATIONS FOR USE) Instructions on how to use a device. Mandated by the FDA. Typically a package insert. INCUBATOR Small companies that specifically serve to develop a need or concept at the early stages. An incubator may incubate multiple device concepts for a significant period of time. Successful products may result in the spin-out of a company from the incubator into a standalone entity. INFERIOR lower in position INFLAMMATION A localized physical condition in which part of the body becomes reddened, swollen, hot, and often painful, especially as a reaction to injury or infection. INFORMED CONSENT Consent by a research subject that consent indicates they are fully aware of all aspects of the trial prior to participating, including both the risks and potential benefits. ISO International Organization for Standardization. A nongovernmental network of national standards institutes that establishes standards of quality. LATERAL of, at, towards, or from the side or sides. LUMEN In biology, a lumen (from

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Latin lumen, meaning â&#x20AC;&#x2DC;an openingâ&#x20AC;&#x2122;; plural lumina) is the inside space of a tubular structure, such as an artery or intestine. It also used to refer to tubing used for biomedical applications. MASTOID/MASTOID PROCESS The mastoid process is the portion of the temporal bone of the skull that is behind the ear which contains open, air-containing spaces. MEATUS In reference to the nasal anatomy, it refers to the space/ passage under the turbinates/ conchae. MEDIAL situated in the medial plane of the body. MEDTECH Medical device technology. A short form to allow comparisons to Biotech, for instance. MEDICAL MANAGEMENT It is an umbrella term that encompasses the use of IT for health, disease, care and case management functions MIDDLE EAR It is the portion of the ear internal to the eardrum/ tympanic membrane, and external to the oval window of the inner ear. The ossicles are housed in this portion of the ear. MORBIDITY When a human is harmed in some way (short of death) by infection, decreased quality of life, extended hospital stay, physical impairment, etc.

MUCOCILIARY CLEARANCE It refers to the self clearing mechanism of the mucous membrane with the help of the ciliated lining. MUCOSA A mucous membrane or mucosa is a membrane that lines various cavities in the body and surrounds internal organs. It consists of one or more layers of epithelial cells overlying a layer of loose connective tissue. MUCOSAL relating to the mucosa MUCOLYTIC A class of drugs which aid in the clearance of mucus MYRINGOTOMY It is a surgical procedure in which a tiny incision is created in the eardrum (tympanic membrane) and a tube is inserted to relieve pressure caused by excessive buildup of fluid, or to drain pus from the middle ear NASAL relating to the nose NASAL CONCHA (OR TURBINATE) It is a long, narrow, curled shelf of bone that protrudes into the breathing passage of the nose in humans and various animals. It helps warm up the air we breathe so that it can mix with the blood. We have 3 pairs of turbinates in our nose. NASAL SEPTUM It is the bone and cartilage in the nose that separates the nasal cavity into the two nostrils.

NASOPHARYNX It is the upper part of the pharynx, connecting with the nasal cavity above the soft palate to the pharyngeal passageway.

(OME FOR SHORT) Otitis media with effusion (OME) is thick or sticky fluid behind the eardrum in the middle ear.

government funded search engine that provides access to biomedical research papers that have been published in professional journals.

NASOPHARYNGEAL pertaining to the nasopharynx

PARANASAL SINUSES The paranasal sinuses, the frontal, maxillary, sphenoid and the ethmoids are air-filled cavities in the frontal, ethmoid, maxilla, and sphenoid bones

PUSHABILITY Pubhability is the quality of being pushable. In the context of this document, it refers to the ability of the balloon catheter to be pushed smoothly into the guide and retracted.

PATENCY The condition of being open or unobstructed.

QA (QUALITY ASSURANCE) The process that ensures that the product will operate according to its specifications.

NASOPHARYNGEAL ANGIOFIBROMA It is a histologically benign but locally aggressive vascular tumor that grows in the back of the nasal cavity. It most commonly affects adolescent males. NDA (NON-DISCLOSURE AGREEMENT). An agreement between two parties such that the party receiving confidential information from another party will not disclose the information to anyone for a fixed period of time. NITINOL Nickel titanium, also known as Nitinol (part of shape memory alloy), is a metal alloy of nickel and titanium. Nitinol alloys exhibit two closely related and unique properties: shape memory effect (SME) and superelasticity (SE; also called pseudoelasticity) ODEOMA A condition characterized by an excess of watery fluid collecting in the cavities or tissues of the body.

PATULOUS wide open. In the case of the ET, it usually refers to the condition when the muscles stop opening and closing the tube. PHYSIOLOGY Refers to the way in which a living organism or bodily part functions POLYPS Abnormal clumps of tissue growth on a mucous membrane POLYPOID Resembling or in the form of a polyp POC (POINT OF CARE) It is the place in which the actual surgery, medical intervention, or other medical procedure is done. POSTERIOR further back in position; of or nearer the rear or hind end.

OTITIS MEDIA (OM FOR SHORT) Infection in the middle ear that presents with fluid accumulation, inflammation and pain.

PROXIMAL It is situated nearer to the centre of the body or the point of attachment.

OTITIS MEDIA WITH EFFUSION

PUBMED Published Medicine, a

QC (QUALITY CONTROL) The activities designed to catch defective products in the manufacturing before they are released to the customer. QUALITY OF LIFE The degree of well-being felt by an individual. RETRACTION In this case, the pulling back of the eardrum towards the ossicles. RHINITIS (OR STUFFY NOSE) Irritation and swelling of the mucous membrane in the nose RHINOSCOPE A Rhinoscope is a thin, tube-like instrument that allows one to spread the nostril and examine the inside of the nose SHADOWING see Clinical Observation STAKEHOLDERS All parties with some interest in the delivery and

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financing of medical care for patients with a specific medical need. STANDARD OF CARE A treatment process that is well supported by evidence and that a doctor or medical facility should follow for a particular type of patient, disease, or procedure. STANDARD TREATMENT A treatment that is currently in wide use and approved by the FDA and considered to be effective in the treatment of a specifi c disease or condition. SUBJECT A human who participates in an investigation, either as an individual on whom, or on whose specimen, an investigational device is used or who participates as a control. SUPERIOR further above or out; higher in position. SYMPTOMATIC Exhibiting or involving medical symptoms TEMPORALIS FASCIA It is strong, fibrous tissue that covers the Temporalis muscle. It is the area around the ear, on the skull. TINNITUS It is the perception of noise or ringing of the ears when no external sound is present. TRACKABILITY It refers to quality of being trackable. In the context of this project, it refers to the ability of the balloon cather to bend and

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trace the path of the guide. TRADE SECRET Information, processes, techniques, or other knowledge that is not made public but provides the innovator with a competitive advantage. TREATMENT GAP Reviewing methods of treatment for a particular disease to uncover areas where treatment is not used, where it is not effective, or where it does not exist. Treatment-gap analysis is performed in order to find areas for innovation. TURBINATE see Nasal Concha TYMPANIC MEMBRANE or the eardrum is a membrane forming part of the organ of hearing, which vibrates in response to sound waves. TYMPANOGRAM It is a graphic representation of the relationship between the air pressure in the ear canal and the movement of the eardrum, or tympanic membrane, and the tiny bones in the air-filled middle ear. TYMPANOMETRY It is an examination used to test the condition of the middle ear and mobility of the eardrum (tympanic membrane) by creating variations of air pressure in the ear canal TYMPANOPLASTY It is the surgical operation performed for the reconstruction of the eardrum

(tympanic membrane) and/or the small bones of the middle ear (ossicles) TYMPANOTOMY see Myringotomy TYMPANOSTOMY see Myringotomy TYMPANOSTOMY TUBE see Grommet

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REFERENCES Web Links: (10th October 2017) Eustachian Tube , Available at: https://en.wikipedia.org/wiki/Eustachian_tube (Accessed: 30th january 2017). (19th July 2017) Tympanostomy Tube, Available at: https://en.wikipedia.org/wiki/Tympanostomy_tube (Accessed: 2nd February 2017). (29th August 2017) Tympanometry, Available at: https:// en.wikipedia.org/wiki/Tympanometry (Accessed: 2nd February 2017). (6th October 2017) Anatomy of the human nose, Available at: https://en.wikipedia.org/wiki/Anatomy_of_ the_human_nose (Accessed: 1st February 2017). (7th October 2017) Ear Clearing Maneuvers, Available at: https://en.wikipedia.org/wiki/Ear_clearing (Accessed: 4th April 2017). (7th October 2017) Myringotomy, Available at: https:// en.wikipedia.org/wiki/Myringotomy (Accessed: 30th January 2017). A Borangiu, CR Popescu and VL Purcarea (Oct-Dec 2014) Sonotubomanometry, Available at: https:// www.ncbi.nlm.nih.gov/pmc/articles/PMC4316148/ (Accessed: 1st October 2017). Angela Woodward (2017) Angioplasty Balloon, Available at: http://www.madehow.com/Volume-6/AngioplastyBalloon.html (Accessed: 2nd October 2017). Cedars-Sinal (2017) Ganglion Block , Available at: https://www.cedars-sinai.edu/Patients/Programs-andServices/Pain-Center/Head-and-Neck-Pain/StellateGanglion-Blocks.aspx

Ceki Paltura, Tuba Selçuk Can, Behice Kaniye Yilmaz, Mehmet Emre Dinç, Ömer Necati Develioğlu, Mehmet Külekçi (August 2017) Eustachian tube diameter: Is it associated with chronic otitis media development?, Available at: http://www.amjoto.com/article/S01960709(16)30564-6/fulltext David Terfera, Shereen Jegtvig () Nasal Anatomy, Available at: http://www.dummies.com/education/ science/anatomy/the-anatomy-of-the-nose/ (Accessed: 20th September 2017). Dr Oliver Starr (24 February 2015) About Eustachian Tube Dysfunction, Symptoms, Available at: https:// patient.info/in/health/eustachian-tube-dysfunction (Accessed: 25th January 2017). ENT guide (22nd December 2011) Eustachian Tube Catheter, Available at: http://entinstruments.blogspot. in/2011/12/eustachian-tube-catheter.html (Accessed: 24th June 2017). Ethan Soudry, MD Jayakar V. Nayak, MD, PhD (17th February 2015) Nasal Endoscopy, Available at: http:// care.american-rhinologic.org/nasal_endoscopy (Accessed: 2nd February 2017). Healthline Medical (13th January 2017) Sinus Cavities, Available at: https://www.healthline.com/human-bodymaps/sinus-cavities (Accessed: 23rd September 2017). Innaccel (2015) About Innaccel, Available at: http:// innaccel.com (Accessed: 10th Sept 2017). Innaccel (2017) SinuCare, Available at: http://www. sinucare.in (Accessed: 26th September 2017). Jan Modric (7th January 2016 ) Valsalva Maneuver,

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Available at: http://www.ehealthstar.com/test/valsalvamaneuver (Accessed: 2nd October 2017). John Mersch, MD, FAAP (12th July 2016) About Eustachian Tube Dysfunction, Available at: https://www. medicinenet.com/eustachian_tube_problems/article. htm (Accessed: 15th February 2017). Justin H. Turner, M.D., Ph.D. Devyani Lal, MD Jayakar V. Nayak, MD, PhD (20th January 2015) Nasal Anatomy, Available at: http://care.american-rhinologic.org/ nasal_anatomy (Accessed: 1st February 2017). medasil surgical ltd () Types of Nasal packs, Available at: http://www.medasil.com/wp-content/ uploads/2015/06/Medasil-Web.pdf (Accessed: 26th April 2017). NETCELL () Nasal Pack Sterilisation Details, Available at: https://www.networkmedical.co.uk/app/ uploads/2016/07/NETCELL-Epistaxis-PVA-Nasal-PackSpec-Sheet.pdf Spiggle & Theis () TubaVent Spiggle & Theis, Available at: http://www.spiggle-theis.com/en/products/tubaeustachii/tubavent. Stanford Buyers Centre for Biodesign (2016) Stanford Biodesign Process, Available at: http://biodesign. stanford.edu/about-us/process.html (Accessed: 10th September 2017). Ted L Tewfik, MD Professor of Otolaryngology-Head and Neck Surgery, Harpreet Singh, MBBS, MS, FRACGP General Physician (ENT), Head and Neck Surgeon, Australia (Feb 27, 2015) Eustachian Tube Function, Available at: http://emedicine.medscape.com/ article/874348-overview (Accessed: 24th January 2017). Vention Medical (2017) Making a custom Balloon Catheter, Available at: https://www.ventionmedical.com/ design-and-development/tools/semicustom-ballooncatheter/custom-balloon/ (Accessed: 15th July 2017).

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Videos: BalloonSinuplasty (Jan 30, 2017) Acclarent AERA Eustachian Tube Dilation System with Audio, Available at: https://www.youtube.com/watch?v=hJMort6YCI 4&index=13&t=111s&list=PLD0glhizjXbqMA5OGzP-x3SYI1LxkzFa (Accessed: 16th Feb, 2017). Dr Jeeve Kanagalingam (4th April 2015) Eustachian Tube Balloon Dilation, Available at: https://www.youtube. com/watch?v=dBln0VwifP8&index=2&t=6s&list=PLD 0glhizjXbqMA5OGzP--x3SYI1LxkzFa (Accessed: 15th February). Dr Krunal Karade (Jan 20, 2017) Ear Ventilation Tube seen from inside of Nose : Eustachian Tube, Available at: https://www.youtube.com/watch?v=1LrcAVVeD5I& index=9&list=PLD0glhizjXbqMA5OGzP--x3SYI1LxkzFa (Accessed: 16th Feb, 2017). Matthew Isles (Feb 5, 2012) Endoscopic Eustachian Tuboplasty, Available at: https://www.youtube.com/ watch?v=3_7lRcCu-cw&index=6&list=PLD0glhizjXbqMA 5OGzP--x3SYI1LxkzFa (Accessed: 15th February 2017). NoseMD (Jan 20, 2013) Endoscopic Shaving of Nasal Polyps, Available at: https://www.youtube.com/watch? v=dSplW6UZxvU&index=15&list=PLD0glhizjXbqMA5OG zP--x3SYI1LxkzFa (Accessed: 16th Feb, 2017). sinusvideos (Jan 1, 2014) Eustachian Tube Endoscopy, Available at: https://www.youtube.com/watch?v=PY_rR CzXERQ&index=17&t=218s&list=PLD0glhizjXbqMA5OG zP--x3SYI1LxkzFa (Accessed: 18th February 2017). sinusvideos (Nov 27th, 2013) Balloon Eustachian Tuboplasty, Available at: https://www.youtube.com/ watch?v=NroBHiC_x2w&index=5&list=PLD0glhizjXbqM A5OGzP--x3SYI1LxkzFa (Accessed: 15th Feb, 2017). Spiggle & Theis - Medizintechnik (Sep 11, 2015) Eustachian Tube Dysfunction: Treatment with Balloon Dilation, Available at: https://www.youtube.com/ watch?v=nDI92-peLW0&index=12&list=PLD0glhizjXbqM

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A5OGzP--x3SYI1LxkzFa (Accessed: 16th Feb, 2017). House Ear Institute (Apr 25th, 2014) Eustachian Tuboplasty, Available at: https://www.youtube.com/wat ch?v=olXTT6MNN8w&index=8&list=PLD0glhizjXbqMA5O GzP--x3SYI1LxkzFa (Accessed: 16th Feb, 2017). House Ear Institute (May 2, 2014) Endoscopy of the Eustachian Tube, Available at: https://www.youtube. com/watch?v=GkyiuJj3Nv8&index=16&t=278s&list=P LD0glhizjXbqMA5OGzP--x3SYI1LxkzFa (Accessed: 18th Feb, 2017). KEBOMED (Jan 31st, 2013) Balloon Dilatation of the Eustachian Tube, Available at: https://www.youtube. com/watch?v=t8vWWMQufjc&index=7&list=PLD0glhizj XbqMA5OGzP--x3SYI1LxkzFa (Accessed: 15th February 2017). SinusVideos (2010) Eustachian Tuboplasty AS with Microdebrider, Available at: https://www.youtube.com/ watch?v=cqeCNVeJt9Q&index=1&list=PLD0glhizjXbqMA 5OGzP--x3SYI1LxkzFa (Accessed: 15th February). sixesfullofnines (Jun 29, 2015) Eustachian Tube Surgery - The Drs Tv Sh0w, Available at: https://www.youtube. com/watch?v=S5orMkk4l5Y&index=4&list=PLD0glhizjX bqMA5OGzP--x3SYI1LxkzFa (Accessed: 15th February 2017).

Books: Dr. Jagdish Chaturvedi (2016) Inventing medical devices â&#x20AC;&#x201C; A perspective from India, 1st Edition edn., Chennai: notionpress.com. by Paul G. Yock, Stefanos Zenios, Josh Makower, Todd J. Brinton, Uday N. Kumar, F. T. Jay Watkins, Lyn Denend, Thomas M. Krummel, Christine Q. Kurihara (2 Feb 2015) Biodesign: The Process of Innovating Medical Technologies, 2nd Edition edn., USA: Cambridge University Press. Holger Sudhoff (2013) Eustachian Tube Dysfunction, 1st edition edn., Europe: UNI-MED.

References 151

Research Papers: Teschner M1. (2016) Evidence and evidence gaps in the treatment of Eustachian tube dysfunction and otitis media. Available at: https://www.ncbi.nlm.nih.gov/ pubmed/28025605 Schilder AG1,2, Bhutta MF1,2, Butler CC3, Holy C4, Levine LH4,5, Kvaerner KJ6,7, Norman G8, Pennings RJ9, Poe D10, Silvola JT11, Sudhoff H12, Lund VJ1,2.. (2015) Eustachian tube dysfunction: consensus statement on definition, types, clinical presentation and diagnosis.. Available at: https://www.ncbi.nlm.nih.gov/ pubmed/26347263 Adil E1, Poe D. (2014) What is the full range of medical and surgical treatments available for patients with Eustachian tube dysfunction?. Available at: https://www. ncbi.nlm.nih.gov/pubmed/24275798 Kenji Takasaki, MD; Haruo Takahashi, MD; Ikue Miyamoto, MD; Haruo Yoshida, MD;Tomomi YamamotoFukuda, MD; Kaori Enatsu, MD; Hidetaka Kumagami, MD. (2007) Measurement of Angle and Lengthof the Eustachian Tube on ComputedTomography Using the MultiplanarReconstruction Technique. Available at: http://onlinelibrary.wiley.com/doi/10.1097/ MLG.0b013e318058a09f/abstract Sudhoff H1, Ockermann T, Mikolajczyk R, Ebmeyer J, Korbmacher D, Garten D, Schreiber S. (2009) Clinical and experimental considerations for evaluation of Eustachian tube physiology. Available at: https://www. ncbi.nlm.nih.gov/pubmed/19390833 Norman G1, Llewellyn A, Harden M, Coatesworth A, Kimberling D, Schilder A, McDaid C. (2014) Systematic review of the limited evidence base for treatments of Eustachian tube dysfunction: a health technology assessment. - 15 databases - research uptil 2012. Available at: https://www.ncbi.nlm.nih.gov/ pubmed/28025605 Van Roeyen S, Van de Heyning P, Van Rompaey V (2015)

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Value and discrimiative power of ETDQ7. Available at: https://www.ncbi.nlm.nih.gov/pubmed/25891506 Schrรถder S1, Lehmann M, Sudhoff H, Ebmeyer J.. (2014) Assessment of Chronic obstructive ETD using German version of ETDQ7. Available at: https://www.ncbi.nlm.nih. gov/pubmed/24270966 Edward D. McCoul, MD, MPH, Vijay K. Anand, MD, FACS, and Paul J. Christos, DrPH, MS (2012) Validating the Clinical Assessment of Eustachian Tube Dysfunction: The Eustachian Tube Dysfunction Questionnaire (ETDQ7) Available at: https://www.ncbi.nlm.nih.gov/pmc/ articles/PMC3612400/ McCoul ED1, Singh A, Anand VK, Tabaee A.. (2012) Balloon Dilation in Cadavers, Technical feasability, Learning curve. Available at: https://www.ncbi.nlm.nih. gov/pubmed/22374885 Ockermann T1, Reineke U, Upile T, Ebmeyer J, Sudhoff HH. (2010) Balloon dilation eustachian tuboplasty: a feasibility study. - 5 cadavers Available at: https://www. ncbi.nlm.nih.gov/pubmed/20657335 Schrรถder S1, Abdel-Aziz T, Lehmann M, Ebmeyer J, Sudhoff H. (2015) [Bacteriologic investigation of the Eustachian tube and the implications of perioperative antibiotics before balloon dilation]. Available at: https:// www.ncbi.nlm.nih.gov/pubmed/26303520 Abdel-Aziz T1, Schrรถder S, Lehmann M, Gehl HB, Ebmeyer J, Sudhoff H.. (2014) Computed tomography before BETD - is it necessary Available at: https://www. ncbi.nlm.nih.gov/pubmed/24622017 Xiong H1, Liang M1, Zhang Z1, Xu Y1, Ou Y1, Chen S1, Yang H1, Zheng Y2. (2016) Efficacy of balloon dilation in the treatment of symptomatic Eustachian tube dysfunction: One year follow-up study.. Available at: https://www.ncbi.nlm.nih.gov/pubmed/26954860

Williams B1, Taylor BA2, Clifton N3, Bance M4. (2016) Balloon dilation for ET - tympanometric analysis. Available at: https://www.ncbi.nlm.nih.gov/ pubmed/26869258 Schröder S1, Lehmann M1, Ebmeyer J1, Upile T1, Sudhoff H1.. (2016) BDET 5 yr study of outcomes. Available at: https://www.ncbi.nlm.nih.gov/ pubmed/25867023 Kivekäs I1, Chao WC, Faquin W, Hollowell M, Silvola J, Rasooly T, Poe D. (2015) Histopathology of balloondilation Eustachian tuboplasty.. Available at: https:// www.ncbi.nlm.nih.gov/pubmed/25154612 Smith ME1,2, Tysome JR2. (2017) Middle Ear Pressure Changes during Balloon Eustachian Tuboplasty. Available at: https://www.ncbi.nlm.nih.gov/ pubmed/27729557 Todt I1, Abdel-Aziz T2, Mittmann P1, Lehmann M2, Ebmeyer J2, Scholtz LU2, Sudhoff H2. (2016) Measurement of middle ear pressure changes during balloon eustachian tuboplasty: a pilot study. Available at: https://www.ncbi.nlm.nih.gov/pubmed/27844486 Hwang SY1, Kok S1, Walton J1.(2016) Balloon dilation for eustachian tube dysfunction: systematic review. Available at: https://www.ncbi.nlm.nih.gov/ pubmed/27488333 Randrup TS1, Ovesen T2. (2015) An analysis done by two doctors about BET from 12 databases including pubmed Available at: https://www.ncbi.nlm.nih.gov/ pubmed/25605694

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APPENDIX Documents relevant to this project are included in this section. They include various observership records, protocols and reports.

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Cadaver Study Protocol Scope This is an exploratory study that aims to assess the feasibility and safety of 1st generation prototypes of EustaCare. Objective The goal of this study is to test accessing, dilating and visualizing the inside of the Eustachian tube. The angle of access, stiffness of device to enter the ET, diameter feasible to enter ET, optimal length and damage to surrounding tissue will be studied. Product Overview The product being evaluated through cadaveric studies is twofold. • A system to visualize the inside of the ET till the isthmus • A system to dilate the cartilage part of the ET We will be testing: • guiding tube of varying exit angles and shapes • Balloon systems of various diameters • Various mechanical dilation methods • Lighted FO to represent • flexible camera • Effect of vibration on Eustachian tube mucous • Effect of air and water flushing on Eustachian tube mucous • Cadaver Access Study setting The study will be conducted in the Simulation Lab of MS Ramaiah Advance Learning Center, Bangalore, India. The set up has a OT like set up with endoscopic visualization, surgical instruments, overhead lighting, head lamps and consumables. Authorization Permission to conduct the study has been obtained from the center from Dr. Shakuntala G, the head of the center

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for 2 cadavers to be used on March 31st 2017. Cadaver Use The study will be performed on adult cadavers (male or female) between the ages above the age 18. The head is the only portion of the cadaver that will be used. More specifically, the anatomy relevant to the study includes the nose, middle ear, internal nasal canal and the eustachian tube. Appropriate cleaning protocols will be followed and no cadaver material will be removed from the laboratory without prior authorization. Study Personnel People involved Members of the InnAccel team involved with the project will be present during the study. Dr. Jagdish Chaturvedi, a certified ear nose and throat (ENT) surgeon is the principal investigator (PI) for this study. The use of the device in the cadaver will be primarily conducted by him. Assistance will be provided by Pooja Kadambi (Lead Systems Engineer), Gaurika Singhal and Aboli Joshi (Design Interns NID). Training Prior to the study training for all non-medical personnel associated with the study will be conducted. The training will be conducted by Dr. Jagdish Chaturvedi and will cover the relevant anatomy, medical procedure that will be performed (endoscope assisted balloon sinus dilation) and proper protocol when working with cadavers. Training with the procedure and anatomy on the head model was conducted at InnAccel. Materials Equipment (provided by center) • Rigid- 0, 30 and 70 degree endoscopes • Nasal Forceps (B) • Ball probe • Forceps

• • • • • •

Angled Scissors Nasal speculum FESS instruments Suction machine Kidney Tray Endoscopy recording

Equipment (taken from InnAccel) • Rigid- 0, 30 and 70 degree endoscopes, 90 deg throat endoscope • Entraview kit • Portable light source • Needle nose pliers, files, screwdriver set, needle file, wire cutter, dental wire, feviquick • Extra tubing • Used instrument box - cadaver (2 syringes + 6 stainless steel instruments) • Pressure Inflation device • Box of prototypes (refer to prototype list) • Extra nasal packs (2) • Bosch Electric drill • flexible endoscope • Fibre optic (FO) kit, 2 cables • Pioneer System • Masks, gloves, aprons • Iodine solution • Extra eustachian tube catheters • Dremel + flex attachment • Canned Air • Acclarent aera system • Vernier calliper • SinuCare Ballon (used) • Sample Balloons (not part of inventory) • SinuGuide 90 deg, 100 deg (USA + China) • SinuGuide handle + 2 screws • SinuCare Balloons (new batch) Stationery kit • Glue, mseal, feviquick, tape, scissors, post-its, pens, notebooks, clipboards, exacto cutter, white sheets • Consumables (provided by center) • 5ml Syringe • Medical Tape ½ inch • Gauze

• • • • • • • •

Savlon Rubber bands Plastic garbage bag Water Gloves Masks Hand sanitizer Cidex

Test product • EustaCare access tubes • 4 angles (50,53,55,60) • Aera ET System • One balloon with guide and inflator • Flexible tubes • 3 types (diff OD 1.2-2.3mm, thickness and flexibility) • Sample Balloon System • SinuCare balloon • Sample balloon • Visualization aid • Fibre Optic cable in 80 degree tube • Flexible endoscope with guiding system • Methods of opening the Eustachian tube manually • Angled bipolar forceps • Giraffe with tip extension • Ball probes with conical ends for dilation • Nasal packs dilation • Nasal packs cut into small pieces • Eustachian tube catheters • Vibration method • Dremel machine • Engraving attachment with cone and speculum attached • Air nozzle • Canned air • Eustachian tube catheter with nozzle attached Methodology Equipment Set-up 1. Ensure all the equipment is present 2. Check light source 3. Connect scope to visualization/recording set up 4. Check recording set up works

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5. Use syringe with air to ensure no leak in either balloon in prototype 6. Place prototype balloon system into sheath with tip coming out 7. Fill syringe and inflator with saline/water 8. Repeat step 5 to 9 for every scope being tested 9. Arrange all guides, flexible tubing, balloon systems and FO so easily accessible 10. Check ENTraView to confirm it works and attach appropriate scope to it Stage 1: Cleaning and Preparatory experiments 1. Clean the nose using endoscope to visualise and a suction. 2. Apply vibration using the dremel machine in the ear canal. Visualise the opening of the ET with an endoscope to observe if fluids are being drained. 3. Perforate the eardrum and repeat steps 1 and 2 to check effectiveness of vibration. 4. Insert the fibre optic cable into the bony part of the Eustachian tube from the ear using the 80 degree guide. 5. Insert the air nozzle catheter Stage 2: Visualization experiments 1. Insert the guided flexible endoscope into the nose vertically and check if there is enough space to maneuver it into the Eustachian tube. 2. If there is not enough space, break the septum to create space for the scope. 3. Insert the endoscope into the Eustachian tube and observe the clarity and distance of visualization. 4. If tissue is closing around the tip of the scope, use the whisk attachment with the endoscope. 5. Withdraw the flexible endoscope with guide. 6. Use the modified giraffe to increase opening of the ET. Use a scope (either flexible or rigid, as appropriate) to observe the increased cone of vision. 7. Use the bipolar forceps to increase the opening of the ET. Use a scope (either flexible or rigid, as appropriate) to observe the increased cone of vision.

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Stage 3: Dilation experiments 1. Use the 55 degree guide to insert the SinuCare balloon (only proximal) into the Eustachian tube under the view of a rigid endoscope. Inflate the proximal balloon using the inflator up to 10 atm and check the visualization using endoscope. 2. Incase the 55 degree guide doesn’t allow access, change guide (50, 53, 60) and insert and inflate the balloon again. 3. Use the Acclarent Aera system to dilate one of the Eustachian tubes and use suitable endoscope to check visualisation after dilation. • The scope is inserted into the nose to visualize the ET opening • The guide tip is inserted into the nose and aligned to opening • Flexible balloon catheter is pushed through guide into ET • The markers on the catheter allow for visualization of appropriate positioning • The inflation system is then used to inflate and deflate the balloon • The deflated balloon catheter is then withdrawn 4. Use the selected guide to insert the extra sample balloon into the Eustachian tube, inflate and check visualization. 5. Use the conical probes through the pharyngeal and nasal passages with a 70 degree scope to guide to dilate. • Insert Eustachian tube catheter to plug the eustachian tube with nasal packs. • The nasal pack is preloaded at the tip of the ET catheter • The tip of the catheter is inserted into the nose and passed along the floor of the nasal cavity till it touches the posterior pharyngeal wall. The tip is now in the nasopharynx. • It is then rotated 90° medially and drawn forward till it meets resistance. The tip is now touching the posterior free end of the nasal septum. • At this point, the tip is rotated 180° laterally so that it enters the opening of the Eustachian tube in the lateral wall.

• •

The nasal pack is pushed into the opening of the eustachian tube using the wire insert. The nasal pack can be left inside to absorb the mucous and other fluid from eustachian tube lining and allowed to expand, the catheter can be used to irrigate the nasal pack incase it doesn’t expand by itself. The nasal pack can then be removed by pulling the string at the end using forceps. Use vibration to check if the inserted nasal pack moves.

validate certain design decisions. The comparison table to the Acclarent system is not a criteria for success but useful information on benchmark for existing standard of care. Timeline The study will span 1 day and utilize 3-5 hours. Testing will be completed by March 30th 2017.

Stage 4: Dissection To assess damage and further understand the anatomy, create an incision under the jaw and dissect till the Eustachian Tube is visible. Clean up All instrument covers, disposables and bench system are disposed into biohazard waste bins with other disposables. Imaging and recording equipment are wiped down with alcohol wipes, The prototype, scopes and forceps will be soaked the antiseptic (Cidex) for 24 hours then dried. No product used in the cadaver study will be used in clinical practice. Data Analysis Data will be gathered using the tables below along with digital photography and videography of the study. A recording of the procedure inside the nasal passage will be obtained through the endoscopy recording system. No statistical analysis will be performed. Measurements and clinical input will be gathered where necessary. Criteria for Success All the success criteria marked by a highlighted row on the observation table should have the appropriate YES/NO response in order for the current concept/ prototype to be considered appropriate to move on to the next stage of development. Else, suitable corrective measures will be indicated. Having favorable responses to other observation parameters while not essential to success will help

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Cadaver Study Report Study setting The study was conducted in the Simulation Lab of MS Ramaiah Advance Learning Center, Bangalore, India. The set up has a OT like set up with endoscopic visualization, surgical instruments, overhead lighting, head lamps and consumables. The time of starting the study after setup was 10.57 am. Authorization Permission to conduct the study had been obtained from the head of the center, Dr. Shakuntala G for 2 cadavers to be used on March 31st 2017. During the study only one cadaver was used. Cadaver Use The study was performed on an adult cadavers above the age of 18. The head was the only portion of the cadaver used. More specifically, the anatomy relevant to the study was the nose, middle ear, internal nasal canal and the eustachian tube. Appropriate cleaning protocols were followed and no cadaver material was removed from the laboratory.

Jagdish Chaturvedi and covered the relevant anatomy, proper protocol when working with cadavers, and the medical procedures that were performed (endoscopy, balloon dilation of eustachian tube and tympanostomy). Training with the procedure and anatomy on the head model was conducted. Methodology Equipment Set-up • Ensured all the equipment is present, checked light source and visualization setup. • Checked recording set up. • Arrange all prototypes for easy access. • Checked ENTraview and attached appropriate scope.

Members of the InnAccel team involved with the project were present during the study. Assistance was provided by Pooja Kadambi (Lead Systems Engineer at Innaccel), Gaurika Singhal and Aboli Joshi (Design Interns NID).

Stage 1: Cleaning and Preparatory experiments • Cleaned the nose using a suction and endoscope to visualise. • Applied vibration using the dremel machine in the external auditory meatus, the mastoid bone and the mandible. Visualised the opening of the ET with an endoscope to observe fluid drainage. • Perforated the eardrum and removed the ossicles to insert the air pressure nozzle into the bony part of the Eustachian tube. • Aligned the tip of the Eustachian tube catheter (attached to the pressurised air can) with the bony osteum of the Eustachian tube under the visualization of a 0 degree pediatric scope. • Flushed the Eustachian tube with pressurised air. • Disconnected the pipe from the nozzle of the pressurised air can and connected it to a syringe filled with water. • Flushed the Eustachian tube with water using a 55 deg angle from the nasopharyngeal opening.

Training Prior to the study, training was conducted for all nonmedical personnel. The training was conducted by Dr.

Stage 2: Dilation experiments • Used the 55 degree guide to insert the SinuCare balloon (only proximal with mseal ball tip) into

Study Personnel There were two doctors present at the study. Dr. Jagdish Chaturvedi, a certified ear nose and throat (ENT) surgeon and Director, Clinical Innovations and Partnerships at Innaccel. Dr Mohan Jagade Professor and Head of Department, ENT and Head and Neck Surgery, JJ Hospital, Mumbai.

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•

the Eustachian tube under the view of a rigid endoscope. Inflated the proximal balloon using the inflator up to 12 atm and checked the visualization using 70 degree endoscope. The sinucare balloon was reinserted 4 times and readings of how far in it went were recorded. 20 mm Sample balloon was inserted into the 55 degree guide into the nasopharyngeal opening of the ET and inflated uptil 8 atm and checked the visualization using 70 degree endoscope. This was repeated another two times, this time it was inflated upto 12 atm. Applied vibration using the dremel machine in the external auditory meatus, the mastoid bone and the mandible. Visualised the opening of the ET with an endoscope to observe fluid drainage or bubbling.

Stage 3: Visualization experiments • Inserted the guided flexible endoscope into the nostril vertically and checked if there was enough space to maneuver it into the Eustachian tube. • The guide was not stiff enough to enter the ET. The flexible endoscope was removed from the guide and inserted into the other nostril. • A ball probe and rigid endoscope were used to guide the flexible endoscope into the Eustachian tube. • The rigid 70 degree endoscope was pushed directly into the dilated Eustachian tube and could visualise till the isthmus. Stage 4: Fibre Optic experiments • A fibre optic cable was inserted from the ear directly without a guide into the bony part of the ET uptil the isthmus, under visualisation with a 0 degree pediatric scope. The lights were dimmed and it was checked if the light was visible at the nasopharyngeal opening on the ET. • The aera system was tried with a 30 degree scope and then switched to 0 degree. The fibre optic cable was inserted into the balloon, the lights were dimmed, and observed from the middle ear. Stage 5: Dilation Continued

•

• • •

Balloon sample c was inserted into the nasopharyngeal opening with 55 degree guide. The guiding system was changed to acclarent guide. The balloon was inserted all the way through and inflated and the isthmus was cracked The conical probes were inserted into the nasopharyngeal opening of the ET, feedback was recorded. The modified giraffe was used to broaden the opening, it broke. A Nasal pack was inserted into a eustachian tube catheter and guided to the nasopharyngeal opening of the ET. It was pushed in with a wire from the back and left in for a minute. Observations were recorded and then it was pulled out by its string, using forceps. Three more nasal packs were inserted in the same way and observations were recorded.

Clean up All instrument covers, disposables and bench system were disposed into biohazard waste bins with other disposables. Imaging and recording equipment were wiped down with alcohol wipes, The prototype, scopes and forceps were soaked the antiseptic (Cidex) for 24 hours then dried. Data Analysis Data was gathered using the tables below along with digital photography and videography of the study. A recording of the procedure inside the nasal passage has been obtained through the endoscopy recording system. No statistical analysis has been performed. Measurements and clinical input have been gathered where necessary. Timeline The study spanned 1 day and utilized 7 hours. Testing was completed on March 30th 2017. Next steps Visualization The flexible endoscope approach did not work. Other approaches that can be experimented with:

Appendix 161

• • • •

Rigid, angled scope incorporating mirrors/lenses/ prisms Chip-on-tip camera Stiffer guide for the flexible endoscope Methods of scanning that can indicate presence of a blockage (like ultrasound)

Dilation The balloon dilation and nasal packs method worked well. A two-step approach incorporating both of them can be adopted. Study Questions and Answers Did vibration help loosen and release mucous from the ET? The vibrating otoscope nozzle connected to the dremel was placed at the mastoid and inside the ear at dremel settings ranging friom 0-4, the vibration could be felt at almost all the facial bones, but it made no difference to the tissue. No mucous/fluid was displaced from the eustachian tube (an endoscope was placed at the nasopharyngeal opening of the eustachian tube while cnducting this experiment) Did pressurised air help loosen and release mucous from the ET? Yes, when pressurised air was pointed using a eustachian tube catheter into the bony part of the eustachian tube opening from the ear and an endoscope was placed at the nasal end, it was observed that spouts of bubbly fluid/mucous came out. Later, a small paper flag was also placed at the opening using forceps and it was observed that the air managed to displace the paper. Did a stream of water help loosen and release mucous from the ET? When a water jet was inserted through the middle ear, resistance was felt and no water was observed coming out at the nasal opening. The water was instead falling back outside the ear. A red band was observed on looking endoscopically though the middle ear, the catheter had been pressing against a wall. Catheter was

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repositioned and the water jet technique was tried again with no luck. The middle ear looked clean though Was access angle suitable to access ET opening nasally? Which one? 55 degree guide was used to access the ET from the nasal end. The angle was comfortable and allowed access. it was observed that the angle still had to be adjusted manually while inserting anything to ensure that it doesn’t hit the mucosal wall of the eustachian tube. The ideal angle may have been a little larger so as to penetrate the tube more easily but tube was too floppy and tight to allow balloon to enter. Was there indication that the isthmus was reached? A tactile indication was felt everytime a ballon/tube hit the isthmus, it wasn’t easy to go beyond 20-24 mm from the nasopharyngeal opening Was transillumination visible with the fibre optic? Fibre optic guide was inserted into the acclarent balloon and guided into the nasopharyngeal opening of the ET. when observed from the middle ear, transillumination was not visible. When the balloon was taken out, it was observed that about 60 mm had been pushed through and so it might have gone into the skull base. Was visualization into the ET achieved with the mechanical opening devices? The extended giraffe broke, when we tried to stretch the opening and the bipolar forceps weren’t tried, too thick to reach and too big Was visualization achieved with the flexible endoscope? No. 1. It was hard to turn the flexible endoscope into the ET with the guide, since the guide was not made of a stiff enough material to withstand bending 2. tried to insert flexible endoscope without guide and camera by guiding it using forceps and a pediatric endoscope. The teflon coating tore a little while handling the endoscope with the forceps and could not be made to enter the eustachian tube 3. flexible endoscope with sheath/guide was guided

into other nostril from behind the septum into the eustachian tube opening to achieve the angle, using another scope and a ball probe. The sheath/ guide was removed as it was providing resistance. By the time the endoscope made it into the ET, it had gotten mucky and we couldn’t see much. The endoscope was removed, the area was suctioned with a catheter and tried to visualise again. It was concluded that the flexible endoscope gets damaged and mucky easily and we need to make something to prevent it. . Were there any problems during visualisation? Refer above Did the whisk attachment push obstructions out of the way without blocking the view of the scope? The whisk attachment was not used as it could only be used with sheath or guide which was making it harder to use the endoscope. Did both sizes of the whisk attachment fit? Neither Did prior dilation impact the visualization clarity and access? Yes, when the ET opening was dilated from the nasopharyngeal end, it was easy to see into it and visualise the lining even with a 70 degree scope Could the fibre optic be visualised inside the ET when fibre optic is passed into ET from the ear and the scope light is off? Fibre optic guide was inserted into the middle ear using the 80 degree scope and its tip was aligned with the bony opening of ET. FO cable was pushed through the guide to enter into the ET. The FO guide was observed to be too acute an angle to access the bony opening of the ET. Finally, the ET catheter was used to push the cable through. Transillumination was not visible, and the light could not be seen from the nasal end of the ET. Was balloon dilation of ET achieved? Yes, Balloon dilation visibly dilated the cartilaginous end

of the eustachian tube, right up to the isthmus. When viewed using a 70 degree scope, the mucosal lining was visible till the isthmus With which balloon, any damage. Was any permanent stretching observed? No damage was observed, the eustachian tube stayed dilated for a while 1. the ball on top of the balloon that was made stopped it from entering the isthmus BUT made it hard to insert through the guide. 2. The tugging inside the guide, damaged the balloon 3. It was observed that the balloon faced resistance after 16mm, 18 mm, 26 mm and 20 mm respectively after two tries done by pooja and one by Dr.Jagdish and pooja again. 4. When the aera balloon was inserted with the aim to make it out of the ET opening in the middle ear (later by Dr. Jagade, with fibre optic cable), we didn’t see it come out. 63 mm of the balloon went in, it was concluded that we had gone into the skull base/ punctured the carotid artery. How long was it required to keep the tool in to ensure dilation? The balloon was inflated around the same time as it is for the sinuses, a few seconds. Pressure on the inflation device was built up till 12 atm and then deflated Was it easier to access the Eustachian Tube through the nasal passage or pharyngeal passage? What are the advantages and disadvantages of both approaches? Could not access the eustachian tube through the pharyngeal passage because the jaw of the cadaver couldn’t be moved. It was very easy to access the opening though the nasal passage. Did the nasal pack swell up? Yes, the nasal pack did swell up on insertion inside the eustachian tube to it’s full capacity. With surrounding moisture or added moisture? Surrounding moisture was enough for expanding the nasal pack. It did expand within the eustachian

Appendix 163

tube catheter when we couldn’t push it out with ease because of the moisture that entered it because of our tugging. Did the nasal packs dilate the cartilaginous part of the ET? Dilation of the cartilaginous part of the eustachian tube on insertion of nasal packs was observed but it was unclear whether the dilation was caused because of the nasal pack or the bulbous end of the eustachian tube catheter that entered the opening a little. The fluid inside the Eustachian tube got absorbed by the nasal pack. Were there visible changes, permanent stretching? The opening did look dilated after the pack was removed. (Unsure if it was because of nasal pack or the catheter). It was hard to pull the string of the nasal pack out, it kept hiding between the swollen mucosa. The Eustachian Tube catheter had to be cleaned and dried before inserting next one Did vibration from the ear canal move the nasal pack out of the ET? Vibration experiment wasn’t carried out after nasal packs were inserted. Did the conical probe help dilate the ET? The conical probes couldn’t be maneuvered inside the nasal passage because of thick flat middle. One of the conical probes was almost able to go inside the eustachian tube but couldn’t be pushed in easily because of lack of space to move the tool. 3/4 conical instruments couldn’t be inserted

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Clinical Consent Form

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Appendix 167

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Appendix 169

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Tympanogram 1 - May 2017

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Tympanogram 2 Sept 2017

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Product Specification Document

Appendix 173

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Appendix 175

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Appendix 177

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Appendix 179

Observation Docket No.

Doctor Treating

Date

Time

Name

Age

Gender

Observation title

Observation

Doctor recommendation

Dr. Athira

8th May

11:00

Asha Das

Myringitis

Patient complained of ear watering, pain in the ear. She also told the doctor she uses a ear bud. She's being treated by another doctor already for a fungal infection but didn't trust the treatment so came for another consultation. When viewed through an endoscope, there was grey ring of tissue in the outer ear. The tympanic membrane was intact. The patient also complained of low hearing so Dr. Athira used a tuning fork to check at the ear, at the mastoid and in the middle of the forehead

The doctor told the patient to continue the medication prescribed by her previous doctor and stop using earbuds. She also gave her antifungal drops and an antibiotic and asked her to come back in 5 days for a checkup. She has myringitis.

Dr. Athira

8th May

11:10

Mumtaaz

laryngeal odeoma with acidity

The patient had come a few years earlier for a hearing aid but now her hearing is okay. She has an itchy throat, some acidity and feels like cough is always there. She has difficulty eataing and breathing. After endoscopy, the doctor found that the vocal chords are odeomatitis. She asked the patients family if she screams a lot and found out that she does.

The doctor referred her to a speech therapist as she was starting to develop nodules. The doctor also said that she's exerting her voice because she couldn't hear too well. The patient was asked to eat every 3-4 hours, no citrus fruits, no fried food and she shouldn't sleep right after she eats.

Dr. Athira

8th May

11:23

Nandini

kikuchi disease

Patient had been diagnosed with kikuchi's disease (multiple lymph node enlargement) a few years ago. She came with throat pain and was worried that her nodes were infected again. She didn't have fever but it hurt when she was swallowed.

Dr. Athira tried to press the inflammation and check for infection. Dr. athira thought that there might be a small infection in the carotid bifurcation area. She recommended an Ultrasound of the neck to confirm

Dr. Athira

8th May

11:37

Satish

TMJ Referred Pain

The patient complained of earache on the right side. Hurts on biting.

On checking with the endoscope, the doctor found that the patient was having referred earache. He actually had a muscle spasm. The doctor prescribed a pain killer, gel and a heat pack. In case he didn't improve, he was asked to see a dentist

Dr. Athira

8th May

11:43

Rohit

Menier's Disease

The patient had come earlier and was diagnosed with Menier's disease. He was having frequent attacks and came to show the doctor an MRI scan.

The doctor asked him not to eat anything very salty and prescribed stogenol and vertin to increase blood supply in the ears.

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Dr. Athira

8th May