| Abstract: | The needle knife is used for mucosal incision during endoscopic mucosal resection (EMR). The first author has used the needle knife for EMR since 1996 to overcome several limitations. Conventional EMR is not able to be used to remove tumors >15 mm. Excessive burning effect on the margin during strip biopsy leads to misdiagnosis during evaluation of resection margins. Relatively larger specimens could be resected and resection margins evaluated effectively with EMR with needle knife. Nowadays the needle knife is used to perform endoscopic submucosal dissection (ESD) from mucosal incision to submucosal dissection. The advantages of needle knife are as follows: (i) the lumen of the stomach can be kept clear during the whole procedure because of less burning effect; (ii) the procedure time for ESD is short because the needle knife has a very thin body, enabling the mucosal and submucosal layer to be cut quickly; and (iii) the needle knife can provide cutting action with the tip. In contrast, the needle knife has a high potential to cause perforation during incision and dissection. Only experts can use the needle knife safely. The perforated site can be closed endoscopically using hemoclips. To prevent perforation the needle knife should be kept parallel to the gastric wall during dissection. In conclusion, the needle knife has many advantages as well as a higher risk of perforation. However, the success rate for ESD using the needle knife increases with sufficient experience. |
