Autonomous Robotic System with Optical Coherence Tomography Guidance for Vascular Anastomosis

TL;DR

The micro-STAR system autonomously places sutures and manipulates tissue with minimal human intervention, marking the first instance of a robotic system autonomously performing vascular anastomosis on real tissue, offering significant potential for improving surgical precision and expanding access to high-quality care.

Abstract

Vascular anastomosis, the surgical connection of blood vessels, is essential in procedures such as organ transplants and reconstructive surgeries. The precision required limits accessibility due to the extensive training needed, with manual suturing leading to variable outcomes and revision rates up to 7.9%. Existing robotic systems, while promising, are either fully teleoperated or lack the capabilities necessary for autonomous vascular anastomosis. We present the Micro Smart Tissue Autonomous Robot (micro-STAR), an autonomous robotic system designed to perform vascular anastomosis on small-diameter vessels. The micro-STAR system integrates a novel suturing tool equipped with Optical Coherence Tomography (OCT) fiber-optic sensor and a microcamera, enabling real-time tissue detection and classification. Our system autonomously places sutures and manipulates tissue with minimal human intervention. In an ex vivo study, micro-STAR achieved outcomes competitive with experienced surgeons in terms of leak pressure, lumen reduction, and suture placement variation, completing 90% of sutures without human intervention. This represents the first instance of a robotic system autonomously performing vascular anastomosis on real tissue, offering significant potential for improving surgical precision and expanding access to high-quality care.

Figures (9)

• Figure 1: µSTAR System overview. A: LBR Med robotic manipulator and suture tool positioned over the microvascular anastomosis positioning system (MAPS). B: Suturing tool equipped with OCT fiber and microcamera. C: MAPS clamp carriage and nitinol vessel holder.
• Figure 2: Example workflow for µSTAR to place a suture for anastomosis. A: Suture tool first drives the needle outside-inside in the right vessel. B: Suture tool drives the needle inside-outside in the left vessel. C: Resultant suture placed for anastomosis. The vessel can now be rotated for the next stitch.
• Figure 3: Example Optical Coherence Tomography (OCT) sensor signal for vessel edge detection. Tissue template compared to new tissue signal (left). Tissue template compared to nitinol signal (right).
• Figure 4: Software Architecture diagram for the µSTAR system. The green zone represents the hardware components, while the blue and red zones represent the ROS2 and ROS software nodes respecitively.
• Figure 5: Diagram showing the force directions for grip strength testing. Puncture force is measured by puncturing a needle through the vessel. Axial and Tangent forces are measured by pulling suture tied at the vessel edge.