Development of a Coaxial Over-the-Scope Bimanual Robot Enabling Lesion-Aligned Manipulation for ESD.

BACKGROUND

Endoscopic Submucosal Dissection (ESD) requires high expertise as conventional endoscopes cannot provide simultaneous traction and dissection, resulting in unstable visualisation and inconsistent cutting depth.

METHODS

A coaxial over-the-scope bimanual robotic system was developed to enable lesion-aligned traction and dissection while maintaining compatibility with commercial endoscopes. Engineering performance was evaluated, followed by a pre-clinical comparison between robot-assisted ESD (R-ESD) and conventional ESD (C-ESD) using synthetic tissue.

RESULTS

The forceps arm generated sufficient traction (0.581 N), and the coaxial mechanism provided hemispherical manipulation. In pre-clinical trials (n = 30), R-ESD significantly reduced total procedure time (9.20 vs. 11.80 min) and dissection time (2.99 vs. 8.35 min). Depth safety improved with shallower mean depth (2.48 vs. 4.06 mm) and a substantial reduction in muscle-invasion-risk regions (0.15 vs. 29.38%).

CONCLUSIONS

The proposed coaxial bimanual robotic system improves procedural efficiency and depth safety through lesion-aligned manipulation. Its compatibility with existing endoscopes suggests clinical applicability without procedural complexity.