Patent ID: 8038603

Claim:
An endoscope hood which is structured to be attachable to a distal end portion of an insertion portion of an endoscope, the endoscope hood comprising: a cylindrical attachment portion which is configured to be attached via a press-fit connection to the endoscope in a state that, in an attachment position, it is positioned to the distal end portion of the insertion portion in a predetermined direction; an impingement end portion which is structured to contact a distal end surface of the distal end portion, when the cylindrical attachment portion is in said attachment position; an asymmetric cylindrical protrusion portion which is formed on a distal end side of the attachment portion and protrudes to a front side from the distal end portion of the insertion portion of the endoscope; and an attachment state confirming means which is configured to provide a warning that an attachment state of the attachment portion to the distal end portion of the insertion portion of the endoscope is inappropriate when the attachment portion is in said attachment position, the inappropriate state condition being based on an area of the protrusion portion displayed in an observation image of the endoscope, wherein the cylindrical protrusion portion includes a concave portion cut in a circumferential direction on a distal end of the cylindrical protrusion portion.