Head-mounted surgical robots are an enabling technology for subretinal injections

Therapeutic protocols involving subretinal injection, which hold the promise of saving or restoring sight, are challenging for surgeons because they are at the limits of human motor and perceptual abilities. Excessive or insufficient indentation of the injection cannula into the retina or motion of the cannula with respect to the retina can result in retinal trauma or incorrect placement of the therapeutic product. Robotic assistance can potentially enable the surgeon to more precisely position the injection cannula and maintain its position for a prolonged period of time. However, head motion is common among patients undergoing eye surgery, complicating subretinal injections, yet it is often not considered in the evaluation of robotic assistance. No prior study has both included head motion during an evaluation of robotic assistance and demonstrated a significant improvement in the ability to perform subretinal injections compared with the manual approach. In a hybrid ex vivo and in situ study in which an enucleated eye was mounted on a human volunteer, we demonstrate that head-mounting a high-precision teleoperated surgical robot to passively reduce undesirable relative motion between the robot and the eye results in a bleb-formation success rate on moving eyes that is significantly higher than the manual success rates reported in the literature even on stationary enucleated eyes.