Distance-Based Shared Control for Vitreoretinal Surgery
Marius Briel, Dongyue Wu, Maximilian Hess, Ludwig Haide, Nicola Piccinelli, Gernot Kronreif, Marco Pellegrini, Eleonora Tagliabue, Franziska Mathis-Ullrich
AI summary
Problem
Maintaining micron-scale instrument-to-retina distance during endolaser photocoagulation is challenging due to limited depth perception, hand tremors, and the tedious nature of manual telemanipulation.
Approach
The system uses an instrument-integrated OCT sensor to measure real-time distance, feeding this data into a shared control algorithm that autonomously regulates axial depth while providing haptic guidance to the surgeon.
Key results
- Designed a shared control system integrating iiOCT and haptic feedback
- Achieved 4 µm mean axial distance error across 12 pilot participants
- Validated system feasibility and safety on ex vivo porcine eyes
- Demonstrated improved targeting accuracy and reduced cognitive workload
Why it matters
Provides a clinically viable framework for enhancing safety and precision in robotic vitreoretinal surgery through real-time distance sensing and haptic assistance.
Abstract
The fragility of ocular tissues combined with the limited surgical workspace demands precise instrument control and focus, making sensor-integrated robotic systems a promising solution. In this letter, we introduce a surgical system for telema- nipulated endolaser photocoagulation that leverages instrument- integrated optical coherence tomography (iiOCT) for accurate dis- tance measurement. We have developed a controller that maintains a specified instrument-to-retina distance, complemented by haptic shared control to assist the ophthalmic surgeon throughout the procedure. We conducted a pilot study involving 12 participants, including an expert vitreoretinal surgeon, to evaluate the system’s performance across three levels of user assistance. The distance- based controller demonstrated a significant improvement in axial precison compared to telemanipulated trials, achieving a mean error of 4 μm and a standard deviation of 69 μm across all subjects. Experiments conducted on porcine eyes confirmed the feasibility of our approach on ex vivo tissues.