Endoscopic submucosal dissection by using a flexible Maryland dissector: a randomized, controlled, porcine study (with videos)

BACKGROUND: Endoscopic submucosal dissection (ESD) is a minimally invasive method for en bloc removal of GI lesions. Current ESD methods and devices have limitations, including long procedure times, technical difficulty, safety, and availability. OBJECTIVE: The aim of this study was to evaluate a blunt submucosal dissection technique and compare it with ESD by using the insulated-tip (IT) knife. DESIGN: Randomized, controlled, animal study. SETTING: Animal facility laboratory. INTERVENTION: Twelve gastric lesions were marked by using electrocautery. After submucosal injection, a circumferential mucosal incision was created. ESD was then performed by using either the IT knife 2 (n = 6) or the flexible endoscopic Maryland dissector (n = 6). MAIN OUTCOME MEASUREMENTS: Median time for IT knife ESD versus median time for Maryland dissector ESD. RESULTS: Median time (IQR) for IT knife ESD was 43 minutes (range 36-50 minutes). The median time (IQR) for Maryland dissector ESD was 32 minutes (range 22-41 minutes; P = .09). The resection specimens obtained with the Maryland dissector tended to be larger, with a median (IQR) of 20.2 cm(2) (range 16.4-23 cm(2)) when compared with specimens resected with the IT knife, which yielded a median (IQR) resection area of 15.9 cm(2) (14.8-18.7 cm(2); P = .08). Complete en-bloc resection including all of the electrocautery markings was achieved in all cases. There were no perforations. There were two minor hemorrhages in the IT knife group and 3 in the Maryland dissector group. LIMITATIONS: Nonsurvival setting, small sample size. CONCLUSION: The flexible Maryland dissector was demonstrated to be efficient, safe, and feasible for facilitating gastric ESD in a live animal model. [ABSTRACT FROM AUTHOR]