Endoscopic submucosal dissection (ESD) permits the resection of large gastrointestinal epithelial neoplasms and neoplasms with submucosal fibrosis in an 'en bloc' manner. However, the high frequency of complications accompanying ESD and its complex processes suggests that the process requires improvement.
In order to perform ESD more easily, safely, and efficiently, a water jet short needle knive (Flush knife) is proposed. Emitting a jet of water from the tip of a sheath enables submucosal local injection with a knife itself without replacement of operative instruments, which leads to efficient treatment. In this lecture, indications, limitations, problems of conventional endoscopic resections, and technical details, applications and tips of the water jet short needle knive devices are fully exposed.