Conventional and underwater ESD for superficial colorectal neoplasms
The study compared conventional endoscopic submucosal dissection (CESD) and underwater endoscopic submucosal dissection (UESD) for removing superficial colorectal neoplasms (SCNs). UESD was hypothesized to offer procedural advantages by utilizing buoyancy to lift lesions, potentially reducing dependence on gravity and improving visualization. The primary endpoint was dissection speed, calculated as the specimen area divided by total procedure time.
The trial randomized 139 patients, with 69 undergoing CESD and 70 undergoing UESD. Results showed no significant difference in median dissection speed between the two techniques (CESD: 17.4 mm²/min vs. UESD: 19.9 mm²/min; P=0.19). However, multivariate analysis revealed that the lesion’s position relative to gravity influenced dissection speed. CESD was more effective for lesions on the nongravity side, while UESD performed better for lesions on the gravity side. Both techniques achieved high safety outcomes, with en bloc resection and no perforations.
In conclusion, neither technique universally outperformed the other, but tailoring the method to lesion orientation could improve procedural efficiency.
