A novel robot-assisted subretinal injection system: preliminary validation in ex vivo porcine eyes

To evaluate the application of a novel, partially automated, robot-assisted ophthalmic surgery for subretinal injection, a study was conducted comparing manual and robot-assisted injections performed by doctors of varying experience levels on fresh, isolated porcine eyes. This system was developed by a team from Harbin Institute of Technology. The core component is a specialized microneedle with adjustable puncture angle and integrated force-sensing capability. It enables flexible intraocular manipulation during subretinal injection procedures and performs autonomous retinal puncture guided by force feedback. Results showed that robot-assisted injections by all doctors achieved a 100% success rate without safety events such as retinal laceration or RPE penetration. While the senior doctor exhibited the highest manual injection success rate and lowest safety event probability, medical students showed the opposite. Compared to manual injection, robot-assisted injection demonstrated smaller needle force variation, more regular retinal "bubble" shape, and more stable subretinal fluid volume (p < 0.05). The surgical robot can accurately perform automatic subretinal injection with high success and good safety, potentially shortening the learning curve and replacing manual operation in the future.