ROBOT-ASSISTED ENDOSCOPIC SUBMUCOSAL DISSECTION USING DISPOSABLE TIP-MOUNTED ROBOTIC MODULE: FIRST EX VIVO RESULTS

Endoscopic Submucosal Dissection (ESD) is a nascent endoscopic therapeutic procedure that enables en bloc removal of early-stage gastrointestinal neoplasms. While the prognosis for patients who undergo successful ESD is good, the remote locations of these lesions can require substantial dexterity and appreciable cognitive work load, increasing the possibility of adverse events. To address these technical challenges, we developed a tip-mounted robotic system, EndoMODRA (Endoscopic Module for On-Demand Robotic Assistance), which interfaces with commercially-available endoscopes and provides additional dexterity and feedback via on-board actuators and sensors to improve therapeutic yields and facilitate dissection. To assess the performance of EndoMODRA in performing ESD in an ex-vivo porcine stomach model. The disposable module (Figure 1) mounts onto the distal end of the endoscope, and a robotically-controlled deflection mechanism mechanically engages with standard ESD devices passed through the endoscope (Figure 2a), enabling active lateral control with precision positioning using integrated shape memory alloy actuators and hall-effect sensors. The clinician uses a proximal endoscope-mounted controller (Figure 2b) to control the position of the tool independently from the endoscope, effectively decoupling the tool’s motion from the endoscope motion on an as-needed basis. The system was used to perform a complete ESD on an excised pig stomach, where robot control was recruited during submucosal dissection. An upper endoscope (EG-450WR5, Fujifilm Medical Systems) and ESD knives (DualKnife and ITKnife, Olympus Medical Systems) were also used. (1) The operator was able to achieve successful en bloc lesion removal via ESD with no incidence of perforation. (2) The actuators provide enough force to deflect endoscopic tools for adequate lesion coverage. (3) Lateral movement of ESD knives was appreciably improved. The integrated sensors were not affected by electromagnetic interference generated during electrosurgical dissection. These results suggest system efficacy at performing gastric ESD. Current work focuses on performing robot-assisted ESD on a live animal model to assess any reduction in the cognitive burden associated with performing ESD, as well as improving system ergonomics and endoscopic visualization. This research lays the groundwork for a new class of endoscopic robot modalities that bridge the gap between simplistic, low-cost endoscopic add-on devices and sophisticated flexible endoscopic robotic systems.Figure 2a and bProximal endoscope-mounted controllerView Large Image Figure ViewerDownload Hi-res image Download (PPT)