Clinical Evaluation of an Instrument-Integrated OCT-Based Distance Sensor for Robotic Vitreoretinal Surgery

Matteo Giuseppe Cereda; Salvatore Parrulli; Y G M Douven; Koorosh Faridpooya; Saskia van Romunde; Gereon Hüttmann; Tim Eixmann; Hinnerk Schulz-Hildebrandt; Gernot Kronreif; Maarten Beelen; Marc D de Smet

doi:10.1016/j.xops.2021.100085

Clinical Evaluation of an Instrument-Integrated OCT-Based Distance Sensor for Robotic Vitreoretinal Surgery

Ophthalmol Sci. 2021 Nov 26;1(4):100085. doi: 10.1016/j.xops.2021.100085. eCollection 2021 Dec.

Authors

Affiliations

¹ Eye Clinic, Department of Biomedical and Clinical Science "Luigi Sacco," Sacco Hospital, University of Milan, Milan, Italy.
² Department of Mechanical Engineering, University of Technology, Eindhoven, The Netherlands.
³ Rotterdam Eye Hospital, Rotterdam, The Netherlands.
⁴ Medical Laser Center Lübeck GmbH, Lübeck, Germany.
⁵ Airway Research Center North, Member of the German Center for Lung Research (DZL), Grosshansdorf, Germany.
⁶ ACMIT Gmbh, Wiener Neustadt, Austria.
⁷ Preceyes B.V., Eindhoven, The Netherlands.
⁸ MIOS sa, Lausanne, Switzerland.

Abstract

Purpose: To assess the efficacy of an instrument-integrated OCT (iiOCT)-based distance sensor during robotic vitreoretinal surgery using the Preceyes Surgical System (PSS; Preceyes B.V.).

Design: Single-center interventional study.

Participants: Patients requiring vitreoretinal surgery.

Methods: Five patients were enrolled. Standard preoperative OCT images were obtained. After vitrectomy, a predefined set of actions was performed using the iiOCT-based sensor. Images then were processed to assess the signal-to-noise ratio (SNR) at various angles to the retina and at different distances between the instrument tip and the retinal surface. Preoperative and intraoperative OCT images were compared qualitatively and quantitatively.

Main outcomes measures: The feasibility in performing surgical tasks using the iiOCT-based sensor during vitreoretinal surgery, the SNR when imaging the retina, differences among intraoperative and preoperative OCT images, and characteristics of intraoperative retinal movements detected with the iiOCT-based probe.

Results: Surgeons were able to perform all the tasks but one. The PSS was able to maintain a fixed distance. The SNR of the iiOCT-based sensor signal was adequate to determine the distance to the retina and to control the PSS. Analysis of iiOCT-based sensor A-scans identified 3 clearly distinguishable retinal layers, including the inner retinal boundary and the interface at the retinal pigment epithelium-Bruch's membrane. Thickness values differed by less than 5% from that measured by preoperative OCT, indicating its accuracy. The Fourier analysis of iiOCT-based sensor recordings identified anteroposterior retinal movements attributed to heartbeat and respiration.

Conclusions: This iiOCT-based sensor was tested successfully and promises reliable use during robot-assisted surgery. An iiOCT-based sensor is a promising step toward OCT-guided robotic retinal surgery.

Keywords: ILM, internal limiting membrane; OCT; OCT distance sensor; PSS, Preceyes Surgical System; RPE, retinal pigment epithelium; Robotic vitreoretinal surgery; SNR, signal-to-noise ratio; iiOCT, instrument-integrated OCT.