Towards Localisation of Remote Centre of Motion and Trocar in Vitreoretinal Surgery

Abstract

Minimally-invasive robot-assisted surgery often uses instruments that are pivoted about a trocar. For precise and safe control, the instrument’s remote centre of motion (RCM) is required to match the trocar insertion point. In cases where there are free-moving body parts, such as the eye in vitreo- retinal surgery, RCM and trocar locations can deviate, making estimation techniques challenging. This work addresses this by developing a hardware solution that can concurrently track the RCM and trocar locations for vitreoretinal surgery tools. A solution was developed that consisted of two miniature cameras, an inertial measurement unit and tool-mounting brackets for the Alcon surgical forceps. The system was designed and prototyped using additive manufacturing. A bench setup was used to carry out initial qualitative validation. On-going work will improve the first prototype and then move towards developing a robust RCM and trocar position estimation algorithm.