LATIOS: Latency-Aware Telemonitoring for Injection in Ophthalmic Surgery - an Adaptive Motion Scaling Approach

Abstract

Communication latency in long-distance telerobotic surgery poses a critical safety risk, particularly in high-precision procedures like retinal surgery where tool overshoots can cause irreversible patient injury. This paper introduces the Latency-Aware Telemonitoring for Injection in Ophthalmic Surgery (LATIOS) framework, which enhances safety by adaptively scaling the surgical robot's velocity along the critical axis of tool insertion. Our core contribution is a control algorithm that dynamically modulates the velocity scaling factor based on two real-time, coupled variables: the tool-tip-to-retina distance, estimated via a non-contact, shadow-based method, and the measured communication delay. We validated this system in a transatlantic user study where six participants in North America teleoperated a surgical robot in Europe to perform a series of simulated retinal punctuation tasks. The results demonstrate that LATIOS provides a statistically significant reduction in applied punctuation forces compared to constant control (p = 0.022). This objective safety improvement is achieved through a deliberate safety-efficiency trade-off, with the system enforcing a more cautious pace under high-latency conditions. Our work presents a robust, context-aware safety framework that addresses a key barrier to the clinical adoption of long-distance telerobotic surgery.