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Robotic surgery Robotic tools and systems hold promise for targeted drug delivery within the eye. Dermot McGrath reports The first approved robotic device on the market, the Preceyes Surgical System, has been successfully deployed to perform epiretinal peeling on human patients. Earlier this year the device received CE mark approval to assist surgeons during vitreoretinal surgical tasks under local or general anaesthesia. Another company, Ophthorobotics AG, has been focusing its attention on intravitreal injections, developing a fully automated system for safe and highly precise injections into the eye, noted Mr Charreyon. A magnetically-steered microcannula for performing subretinal injections The technology utilises specific sensors to identify and track patients’ eyes, performs automatic “This is interesting in ophthalmology intravitreal injections, and features a sterile because it allows us to build tools that laminar airflow for reduced risk of infection. are much smaller and more flexible than Patients can be prepared by the nursing staff, conventional rigid tools for increased and the injections are remotely controlled safety,” he said. and monitored by the treating physician Possible applications for the catheter from another examination room or office, include subretinal delivery of drugs, allowing for a larger patient throughput. gene therapies, or stem cells for retinal “The demand for intravitreal injections regeneration, autonomous navigation of a has increased over the past 10 years due to laser tool for treating diabetic retinopathy the availability of new drugs, but also an (DR) or safer epiretinal membrane peeling. ageing population. This type of system will “For drug delivery, this tool would allow potentially increase throughput for clinics the surgeon to precisely navigate to a while increasing the comfort of the patients desired location, hold the device in place, and decreasing the cost of care,” he said. monitor it with OCT and then create this Another new technology being developed subretinal bleb into which therapies are at ETH Zurich is the magnetic steerable injected,” he said. catheter, which could have some exciting For DR treatments, the catheter could be applications in ophthalmology, said Mr connected to a laser and steered to multiple Charreyon. Unlike a conventional catheter, points on the retina to perform a type of which is steered manually, the magnetic targeted photocoagulation treatment. version is operated from a computer via Another more futuristic application of an external magnetic field. This enables the the technology is the deployment of ocular front part of the catheter to be bent in any microrobots – tiny, untethered devices direction with the highest level of precision. that can be controlled inside the eye using magnetic forces. “This could be used for many applications, including loading drugs, by steering it to a desired location and performing slow release of the drugs before it is retrieved from the eye,” he said. Courtesy of Samuel Charreyon MSc
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lthough eye surgery is currently lagging behind other fields of medicine in the use of robotic technology, the indications are that automated devices may soon be deployed for a range of applications such as intravitreal injections, epiretinal peeling or targeted drug delivery inside the eye, Samuel Charreyon MSc told delegates attending a symposium of artificial intelligence at the 37th Congress of the ESCRS in Paris, France. “We have seen two decades of research in robots for eye surgery but there is only one robot that has so far been approved for commercial use and it still needs to prove that it is useful enough to be adopted for standard use in ophthalmology. So, while there is clearly some way to go in eye surgery robotics in general, we are now seeing some interesting technological solutions emerging from the lab that may have a role to play in the ophthalmic field in the near future,” he said. There is a clear case to be made in terms of robotic surgery filling an unmet need in ophthalmology, particularly given the miniscule scale of the tissue structures encountered, said Mr Charreyon, a researcher at the Multi-Scale Robotics Lab at the ETH Zurich University in Switzerland. “Eye surgery requires phenomenal dexterity where we are talking about precision needs that are measured in microns. Hand tremor is a real concern for the precision and accuracy of tissue manipulation. Robotics can offer increased dexterity and stability, and possibly also some sensing and feedback to be given to the surgeon,” he said. He explained that robotic systems for surgery fall into two broad categories in terms of control paradigms: co-manipulation and tele-manipulation. The former approach is where the surgeon physically manipulates the robot, while in the latter scenario the surgeon is completely decoupled from the robot and interacts with it through a console or joystick.
Eye surgery requires phenomenal dexterity where we are talking about precision needs that are measured in microns Samuel Charreyon MSc
Samuel Charreyon: samuelch@ethz.ch EUROTIMES | APRIL 2020
