MULTI-DEGREE-OF-FREEDOM ARTICULATING FORCEPS FOR CLOSURE OF A LARGE MUCOSAL DEFECT AFTER ENDOSCOPIC SUBMUCOSAL DISSECTION IN A PORCINE MODEL

Background: Multi-degree-of-freedom (MDOF) articulating forceps for flexible endoscopy is a unique device with both rotating and bending articulation that can provide active traction by pulling a mucosal flap towards the lumen. We aimed to demonstrate the use of the MDOF articulating forceps for endoscopic submucosal dissection (ESD) and closure of post-ESD mucosal defects in a porcine model.

Endoscopic methods:
This video demonstrates ESD of a 50 mm rectal lesion and closure of the mucosal defect using the MDOF articulating forceps through a double-channel therapeutic endoscope in an explanted porcine colon. After submucosal injection and circumferential mucosal incision, the mucosal flap was grasped with the articulating forceps and pulled up to the luminal cavity by bending the articulation. Strong traction force was applied to the exposed submucosal tissue. By adjusting the bend angle and protrusion length of the forceps and adding rotation as needed, the dissection plane could be maneuvered to the best position for incision.
After completion of ESD, closure of the post-ESD defect measuring 55mm was performed. Similar to traction-assist ESD using the articulating forceps, the edge of the mucosal defect was grasped by the forceps and tented by bending it at the articulation. Tenting the mucosal defect created a beak-shaped edge. This facilitated clip closure by making the width of the mucosal defect less than the opening width of the clip while preventing mucosal intrusion into the defect being closed. For the second clipping, the first clip was grasped and pulled up to the lumenal cavity to create a beak-like shape. In the middle portion, which has the highest risk of separation, the defect was linearized with submucosal layer-to-layer apposition. When placing the very distal clip, the defect edge was pulled proximally by bending the forceps downward to linearize the remaining defect. A total of 7 clips were used to achieve complete closure. The total procedure time including ESD and closure was 43.6min. No muscle injuries and perforations were noted.

Conclusion: The MDOF articulating forceps seamlessly supported ESD and tight layer-to-layer closure with endoclips without changing the scope and instrument. Submucosal layer-to-layer apposition using the articulating forceps allowed for secure and tight closure of large mucosal defects after ESD.