Patent ID: 8357082

Claim:
An endoscopic attachment comprising: a cover portion that is mounted on a distal end of an inserted portion of an endoscope so as to cover a portion of an opening portion of a channel formed in the inserted portion of the endoscope; and an endoscope mounting portion that is fixed to the inserted portion of the endoscope, wherein a non-circular deformed hole is formed in the opening portion of the channel by the cover portion, the cover portion includes a tapered induction portion which has a same circular cross section as the opening of the channel to induce an endoscopic treatment instrument which has a non-circular cross-section corresponding to the deformed hole from the channel to the non-circular deformed hole, the non-circular deformed hole is configured to have a shape capable of being fitted to an endoscopic treatment instrument, which projects from the opening of the channel and has a non-circular cross section corresponding to the non-circular deformed hole, the rotation of the endoscopic treatment instrument is restricted by a fitting of the non-circular cross section in which the endoscopic treatment instrument has with the non-circular deformed hole, and the endoscopic treatment instrument freely moves in and out of the opening portion of the channel in a predetermined direction while the rotation of the endoscopic treatment instrument is restricted.