EMR+ : A Novel Bimanual Endoscopic Technique for En Bloc Resection of a Proximal Colon LSL-NG/PD Lesion Using a New External Additional Working Channel Device

Abstract

A 90-year-old female patient underwent ileocolonoscopy for iron-deficiency anemia. In the proximal colon, an estimated 22-mm non-granular laterally spreading lesion with discrete areas of pseudo-depression (LSL-NG/PD), Paris IIa+IIc, emerged across a fold (Fig. 1a). After submucosal injection of an indigocarmin-supra-renin mixture (Fig. 1b), optical assessment including image-enhanced endoscopy using linked colour imaging (Fig. 1c) and blue laser imaging (Fig. 1d) suggested distorted vessel and surface pattern, tentatively classified as analogous to NICE type 3 lesion (NBI International Colorectal Endoscopic classification). Likewise, pseudo-depressed appearing areas were thus highlighted. Due to concerns of advanced neoplasia and known higher risks of incomplete resections, when applying conventional endoscopic mucosal resection (EMR) technique in across-fold lesions, we opted for additional-working channel (AWC)-assisted resection, alternatively designated EMR+, as a novel endoscopic tool for en bloc resections of difficult colorectal lesions [1]. In consequence, an AWC device (Ovesco Endoscopy, Tübingen, Germany) was externally mounted onto the scope’s tip with the external channel oriented contralaterally to the scope’s working channel for maximum triangulation [2] (Fig. 1e, f).