“Cold-water” immersion endoscopic resection: Novel therapeutic technique for nonampullary duodenal lesions

Underwater conditions have recently been used during duodenal endoscopic treatment¹; however, peristalsis remains a problem. Although antispasmodic medications can be administered, their effects are sometimes inefficient. Contraindications of butylscopolamine include glaucoma, arrhythmia, and prostatic hypertrophy, and glucagon is associated with the development of diabetes mellitus. The cooling effect of cold water was reported to suppress peristalsis in the esophagus and large intestine via the activation of temperature-sensitive ion channels.^{2, 3} This report presents two patients with nonampullary duodenal lesions with severe peristalsis who were successfully resected using underwater endoscopic mucosal resection with cold water (CW-UEMR) (Video S1). A 75-year-old man had a protruding lesion at the superior duodenal angle with a diameter of 4 mm (Fig. 1a–c). A 54-year-old man had a 10 mm tubular adenoma in the descending duodenum (Fig. 1d–f). In both patients, endoscopic resection via UEMR was attempted using room-temperature saline. However, stable visualization could not be maintained because of severe peristalsis, even after the intravenous administration of glucagon. Thereafter, 60 mL of saline cooled to ~0°C (in ice water) was applied using an endoscopic channel (Fig. 2). The peristalsis was suppressed, and en bloc resection was achieved in a stable visual field within a few minutes. Neither patient experienced adverse events. As the underwater intraluminal pressure is low and the duodenal lumen is narrow, maintaining the visual field is difficult during underwater endoscopic procedures, especially in patients with severe peristalsis. Although the optimal approach to achieving the cooling effect may remain unclear, and caution may be required regarding hypothermia when using large amounts of cold water, CW-UEMR is an easy-to-use technique that is inexpensive and requires no special devices. In addition, UEMR with room-temperature saline can easily be converted to CW-UEMR as necessary. This novel technique is useful during endoscopic resection.

Author R.I. has received honoraria for lectures from Olympus Corporation, FUJIFILM Medical Co., Ltd, Daiichi Sankyo Co., Ltd, Miyarisan Pharmaceutical Co., Ltd, AI Medical Service Inc., AstraZeneca, and Ono Pharmaceutical Co., Ltd. The other authors declare no conflict of interest for this article.