Abstract
Purpose :
Advancements in robotics and computing technology enabled robotic enhanced surgeries in many medical sectors, but due to the special requirements such technologies have not been successfully adopted in opthalomology yet.
A newly developed prototype, focusing on cateract surgury, demonstrates that robotic enhanced and even semi-autonomous surgeries are feasible using todays technology.
Instead of using an external laser and fixating the eye, as done in previous works, the capsolotomy will be cut by the robot using an electric high-frequency (HF) instrument and the positions of eye and instrument are tracked simultaniously.
Methods :
One design goal for the prototype was to keep the hardware as simple as possible, using mostly of-the-shelf parts, while still accomplishing high percision and the speed needed for a fluent surgery.
The setup consists of an industrial robotic arm (Universal Robots UR3e), with a special attachment, to guide the instruments and a stereo camera used for eye tracking and imaging, replacing the surgical microscope.
The stereo camera itself is constructed from 2 syncronised global shutter, color cameras (IDS Imaging Development Systems U3-3561XLE) and a light source in the center providing the red reflex.
The feasibility is evaluated using mechanical eye models (for instrument guidance), fotorealistic dummy eyes (for tracking) and pig eyes (for the whole system).
Results :
The 3D camera (2 x 1920 x 1200 Pixel, >40Fps) is able to triangulate a point in the 3D workingspace (100 x 60 x 60 mm) with +-0.05mm accuracy. And the robot can position any part of the instruments with +-0.05mm accuracy as well. This enables the robot to guide instruments within the anteriour chamber using the small opening at the limbus as access and pivot point. Very fluid, human like motions at comparible speeds were archived (compared to human performed surgery recordings). Possible positions and tool configurations for the robot where identified that maximise motion range while avoiding collisions and singularities.
Conclusions :
Robot guided surgeries within the anteriour segment of the eye are feasible. This technologie can allow high precision and repeatability in surgery outcome even for less trained surgeons. Steps of the surgery could even be performed autonomous, supervised by the surgeon.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.