13 minute read
Whatever ‘road’ one chose, there’s only one common goal: the patient’s desired refractive outcome
The Many Roads to Refractive Surgery Success
by Hazlin Hassan
In order for refractive surgery for myopia to be a success, it needs to safely achieve a patient’s desired refractive goal.
But there are several ways of doing this, from laser refractive surgery to implantation of phakic intraocular lens (PIOL).
ICL, the winner
Phakic intraocular lens (PIOL) debates over the last two decades have pitted it against laser vision correction (LVC), with vigorous discussions over design, material, and patient selection.
“PIOLs ICL is the way to go,” Dr. Alaa Eldanasoury of Magrab Hospital in the Kingdom of Saudi Arabia, told the session on Sunday at the still on-going 37th World Ophthlmology Congress (WOC 2020 Virtual®).
What are the advantages of implantable collamer lens (ICL) over LVC? It preserves quality of vision for the rest of the patient’s life, retains the cornea biomechanics and there is no risk of ectasia. So why hasn’t ICL replaced LVC yet? Patients prefer LVC as the perception is that it is less invasive. LVC in low and moderate myopia is good enough to make them happy. But the cost of ICL is lower compared with laser.
“They [patients] don’t know what they are missing. If they have an ICL, they will have better vision,” said Dr. Eldanasoury.
An ideal PIOL needs to be biocompatible, stable, and predictable. It has to preserve quality of vision, allow fast recovery and be easy to remove or exchange. It must also possess a safe and long track record.
“ICL’s superiority over LVC is documented. The safety of the collamer material has been proven over more than 25 years,” he concluded.
PIOLs beyond myopia
PIOLs can not only correct myopia but it has a therapeutic role in anisometropic myopic amblyopia in children, said Prof. Ahmad El-Massry from the Faculty of Medicine at the Alexandria University in Egypt.
He shared a study on PIOLs to correct high myopia amblyopia in children which yielded the following results: More than 3 Snellen’s lines improvement of BCVA in all children, and no loss of BCVA in any patient. PIOLs were also very well tolerated in the pediatric eye. Results at 24 month showed a mean pre-operative BCVA of 0.2 (range 0.05-0.7), and mean postoperative BCVA of 0.8 (range 0.5 - 1.0).
Anatomical outcomes included an excellent tolerance of ICLs, no inflammatory reaction, no elevation of intraocular pressure (IOP), good position of ICLs, and no cataract or secondary increase of IOP.
“Collamer copolymer phakic ICL to correct high unilateral myopia is a good option in cases of moderate amblyopia with two years follow-up with good predictability, stability in refraction and IOP, no significant endothelial cell loss, better stereoscopic vision, and increasing in quality of life,” he said.
To SMILE or not to SMILE
predictable, efficient, safe refractive and visual outcomes, complications can occur,” said Dr. Catherine Albou-Ganem of the Clinique de la Vision in Paris, France – the first French center entirely dedicated to refractive surgery, of which Dr. Albou-Ganem is a founding member.
Most of these complications are related to inexperience, are included in the learning curve of the technique, and have a favorable resolution with no lasting effect on the patient’s final visual acuity, she noted.
SMILE possesses several advantages. It is a less invasive corneal surgery, respects the biomechanical properties of the cornea and corneal nerves. There is also a lower risk of developing dry eye and recovery is simplified and shortened. SMILE is safe, predictable, stable, provides quality of vision, and at a high precision.
Due to the absence of flap, the complications of SMILE are less numerous than in LASIK.
Epithelial defects, according to published literature, are the most common complication at 41.9%. It is a mild problem solved in 1 to 2 days with the use of artificial tears, has no effect on visual acuity and presents only in the incision zone. Other complications include DLK, hazy interface, epithelial ingrowth, infection, interface fluid syndrome, dryness of the corneal surface, and ectasia. Overall frequency of postoperative complications was 8.6% which is comparable to what is expected after LASIK.
Dr. Catherine Albou-Ganem
Clinique de la Vision Paris, France
Experts Weigh in fewest surgical procedures and complications — that’s what your patients are looking for. So, certainly on Controversies in I use buckling in phakic eyes with attached vitreous, dialysis, young myopes, or myopes in their Vitreoretinal Surgery 50s or 60 with multiple tears/ lattice; in pseudophakic RDs, where there’s multiple breaks with by Brooke Herron inferior retinal detachment, even geography, can influence power can be properly calculated; vitreous hemorrhage, an abnormal vitreous base
Vitreoretinal surgery vitreous, and extensive is no stranger to lattice degeneration,” said controversy — and Dr. Gaurav Shah of The individual circumstances, Retina Institute in St. Louis, like comorbidities, age, cost or Missouri, USA. surgical decisions. Of course, this • 87% prefer vitrectomy means there isn’t necessarily “When vitrectomy is chosen a one-size-fits-all solution to every surgical dilemma — thus, surgeons should have When vitreoretinal procedures go head-to-head, which will rise to the top? for repair of primary uncomplicated RRD, through a simple but as many tools and techniques in their armamentarium as possible. In retinal detachment (RD): thorough PPV, you can get high anatomic and functional success So, which techniques are most widely • 33% prefer lens sparing Adjunct procedures like scleral used? To answer, ophthalmologists vitrectomy buckling are unnecessary in eyes discussed their preferences during a “Surgery must be performed in without PVR or without significant session called Surgical Controversies two steps because: not all patients risk factors for PVR — these in Vitreoretinal Surgery: The Debate develop cataracts; surgery affects adjuncts increase both the cost and on the third day of the 37 th World the eye’s anatomy and therefore morbidity of the procedure,” said Dr. Ophthalmology Congress (WOC2020 alters final refraction, especially if Mark Johnson of the University of Virtual®). scleral buckling was performed; IOL Michigan, USA. with significant adherent rates, and low complication rates. Also, during the session, a live poll asked delegates to vote on their preferences for final refraction is also altered due to silicone oil use; IOL does not For high myopic macular hole the conditions discussed. Here are those results: affect intraoperative visualization; and there is a lower incidence of detachment: intraoperative complications,” • 100% prefer vitrectomy and In non-tractional diabetic concluded Dr. Arturo Alezzandrini of the University of Buenos Aires in ILM peel “I think the pars plana vitrectomy macular edema (DME): Argentina. with large ILM peeled area and an inverted flap should be the • 18% prefer early vitrectomy • 66% prefer vitrectomy with first option to increase the retinal
The cost of vitrectomy is equal routine lens extraction elasticity and macular hole closure to two doses of aflibercept or “I am pro-routine lens extraction, rate. Less complex surgery is always ranibizumab. So pars plana and the association between phacoa better surgery, and more complex vitrectomy (PPV) is less expensive vitrectomy and IOL implantation surgeries have to be reserved than multiple injections of antiin phakic eyes is an alternative to for failed cases,” explained Dr.
VEGF agents. It has also been shown increase the success rate of the Carlos Mateo of the Instituto de to be effective in both tractional and primary vitrectomy for RD and may Microcirugía Ocular in Barcelona, non-tractional DME, according to Dr. be considered for specific cases,” Spain.
Makoto Inoue of Kyorin Eye Center stated Dr. Mauricio Maia of the in Tokyo, Japan. Federal University of São Paulo in • 0% for macular buckling Brazil. “Macular buckling appears to • 81% prefer repeated IVT improve the success rate on its injections “Repeated injections carry In rhegmatogenous retinal own, or in combination with PPV, especially in the presence of much lower risk compared with vitrectomy,” noted Prof. Timothy Lai detachment (RRD): chorioretinal atrophy,” said Prof. Marco Mura of the King Khaled of the Chinese University of Hong • 12% prefer scleral buckling Eye Specialist Hospital in Saudi
Kong. “Best final outcomes with Arabia.
“There’s a need to integrate AI within clinical pathways. For now, we may need “humancentered AI” in order to get deep learning to work better for us.” - Dr. Fred Hersch, Google Health
AI in Ophthalmology: Myths, Controversies and Evidence
by Joanna Lee
This session on Day 3 of the 37 th World Ophthalmology Congress (WOC2020 Virtual®) was an excellent starter course for ophthalmologists seeking to understand how deep learning could be integrated into clinical practice, its current developments and limitations.
In a presentation titled How to decipher an AI paper in Ophthalmology. Prof. Daniel Ting from the Singapore
National Eye Centre shared several helpful parameters and comprehensive overview of artificial intelligence (AI) papers and questions to ask as guidelines when reading an AI literature.
What questions do the study answer, what are core components in an AI system, what are good test datasets, appropriate deep learning techniques, how to assess clinical diagnostic performance and so on. Prof. Ting also answered some questions like what is enough in terms of numbers to train:
“The more unique a condition is, the less number to train,” he noted. Also, Prof.
Ting reiterated Ali Rahimi’s assertion that AI learning “has been a form of alchemy”. Singapore, gave a broad picture of what AI, machine learning and deep learning are all about. Besides explaining how AI is being applied to ophthalmology currently, he also addressed three myths in particular. First, while data is an essential ingredient, the quality of labels is equally as important, he said. It is also a myth that a high accuracy model is sufficient for clinical impact. Rather, there’s a need for “translational research to reach clinical and system impact.” Third, translation into clinical settings is unfortunately not as straightforward. Dr. Hersch proposed that human centered AI could be the solution with mixed methods that could help researchers and clinicians, engineers and patients unlock the potential of AI for healthcare.
Currently, a prospective trial of AI in 9 clinics within the National DR Screening Program is ongoing (Rajavithi Hospital in Thailand) while the Singapore Eye Research Institute is utilizing AI in its health economic assessment study.
During a presentation titled Where would AI fit in clinical care pathways in ophthalmology?, Dr. Michael Chiang, associate director of OHSU Casey Eye Institute in Oregon, United States, said AI could potentially be applied to diagnosis; it can be used for serial follow-up, prognosis and modeling also, among other areas. He made an insightful comparison of how patients’ health records or case notes went from narrative text to structured text when using traditional paper to write versus being entered as electronic data. He said this shows that the technology we give people to work with affects their process of cognition.
Dr. Stephen Cook from South Africa made an engaging case about using AI in ophthalmology from a developing country’ perspective; his presentation has that same title! Dr. Cook addressed the issue of how screening for the eyes usually have less priority in the government compared to the “big fish” like hypertension or chronic kidney disease. His assertion is that, fundus photos can very well predict the end of organ damage. “If we can prevent progression by using technicians and technology, we can greatly improve the cost of healthcare,” he said. Dr. Cook also said the cost of AI can also be reduced when you have a human and AI working together. AI can not only be applied to help in diagnostics but also help inform best practices in eye care such as not overprescribing treatment modalities.
Hong Kong’s Dr. Carol Cheung, on the other hand, shed light on ocular imagingbased AI solution for Alzheimer’s disease. Besides showing recent studies that demonstrated a link between retinal measures with dementia, Dr. Cheung also said AI deep learning has huge potential to automatically interpret retinal images for stratification of high-risk age-related macular degeneration.
Further, the discussion segment revealed current limitations of AI.
“The bigger problem is how we integrate technology into clinical pathways,” said Dr. Cook. Dr. Cheung concurred and gave an example of the need for AI in triage conditions. “AI needs to be integrated into a human operation system. We have to train graders to recognize normal and advanced diseases themselves and use AI in the interim of the disease and spread the spectrum of the disease in between more accurately,” she explained.
Preventing Vision Loss Around The Globe
by Hazlin Hassan
Aging populations, changing lifestyles and limited access to eye care, particularly in lowand middle-income countries, are among the main factors behind an increasing number of people with vision impairment, according to the first World Report on Vision launched last year by the World Health Organization (WHO).
Stronger integration of eye care is needed within national health services, as well as the key basic steps of prevention, early detection, treatment and rehabilitation to ensure that the eye care needs of more people are met.
In light of the World Report on Vision’s findings, several esteemed speakers from around the world discussed at the 37 th World Ophthalmology Congress (WOC2020 Virtual®) the ways in which global eye care can be advanced.
The right to sight
Back in 1999, 80% of global blindness was avoidable.
“Eighty per cent was really embarrassing for eye care professionals because we recognized that with more efforts and services, we could have saved many more people from blindness,” said Dr. Ivo Kocur, CEO of the International Council of Ophthalmology (ICO).
A joint project by WHO and the International Association for the Prevention of Blindness (IAPB) set out to decrease the numbers by working with national governments and nongovernment organizations (NGOs) to provide training, interventions and infrastructure development. It showed that an international collaboration in eye care through a unified approach can help to fight the scourge.
The first contact, or primary eye care, needs to be strong so that the eye conditions which are vision-threatening are properly recognized, treated in a primary manner or the patients are referred for advanced care, and also that the eye care is integrated in the system of health care.
Advocating for the prevention of blindness
At least 2.2 billion people live with vision impairment, and in at least 1 billion of these cases, vision impairment could have been prevented or has yet to be addressed, said Mr. Peter Holland, the CEO of IAPB.
Unaddressed refractive error makes up 23.7 million cases, while cataracts, glaucoma, corneal opacities, diabetic retinopathy (DR), trachoma and unaddressed presbyopia make up 65.2, 6.9, 4.2, 3.0, 2.0 and 826 million cases, respectively.
The impact of the COVID-19 pandemic has seen most services heavily curtailed or stopped, and restarting services has not been straightforward. As such, there is a risk that eye health will lose ground, he warned.
The role of the IAPB has been to conduct webinars, share stories, and adopt a coordinated sector approach, working
with the World Health Organization, United Nations and other global bodies. Recognizing the seismic impact of COVID-19, IAPB is working hard to inform and persuade global leaders about the magnitude and unacceptability of vision loss globally.
Dr. Ivo Kocur
CEO, International Council of Ophthalmology (ICO)
Only the best will do
“We need to reach everyone who needs eye care,” said Dr. R.D. Ravindran of the Aravind Eye Hospital System in India. He stressed the importance of making ophthalmic services accessible, affordable and trustworthy.
There should be an informed decisionmaking and consenting process for patients. Patient-centered goals revolve around creating access for patient care, being responsive to patient needs, transparent pricing, minimizing the cost of the treatment, and ensuring follow-up for all patients.
“High quality eye care should be safe,” said Dr. Ravindran. Treatments must minimize harm, including medical errors such as the wrong lens implant, wrong site, and wrong procedure.
There needs to be clear guidelines to prevent infections such as endophthalmitis and preventable surgical complications should be minimized.
Clear instructions should be given on follow-up care after surgery and when to return for postoperative assessment. At the end of the day, the aspiration is to eliminate needless blindness by providing high quality, safe, compassionate and affordable eye care to all.
