Dynamic water gravity rotation for endoscopic submucosal dissection: changing the location of the lesion.

A 57-year-old man was admitted to our hospital for endoscopic submucosal dissection (ESD) for early gastric cancer. The lesion was located at the anterior wall of the proximal antrum to the lower body. After incision [1,2], about 350 cc of distilled water was infused into the stomach (●" Fig.1). The weight of the water changed the shape of the stomach, so that the anterior wall rotated from the 9 o’clock direction to the 6 o’clock direction (●" Fig.2). Repositioning the lesion made it easier to perform dissection using an insulation-tipped diathermic knife-2 (IT-2) (●" Fig.3). As the final step, we aspirated water to reposition the lesion back to 9 o’clock, so that we were able to cut the edge of the lesion more efficiently (●" Fig.4). It is technically difficult to dissect a lesion at the anterior wall of the proximal antrum to the lower body, because of partially obstructed access for knives and a smothered operation field. The IT-2 has advantages, including a low risk of perforation and shorter operation times, but blind operation increases the risk of accidental perforation and bleeding [3]. We used dynamic water gravity rotation (DWGR) to obtain clearly visualized dissecting points and a precise approach by the IT-2. Filling the fundus with water results in counterclockwise rotation of the stomach and enables the IT-2 to approach the inflated submucosa in a precise parallel manner. The efficacy of dissection by the IT-2 is maximized when the blade is parallel to the inflated submucosa. By the removal of water, the lesion can be relocated back to 9 o’clock, therefore making it easier to cut the edge of the lesion. We conclude that DWGR is useful for relocating gastric lesions to facilitate ESD, especially for lesions at the anterior wall of the proximal antrum to the lower body.