Patent ID: 8202213

Claim:
A medical device, comprising: an image pickup section that is able to pick up an image of a tube cavity in a subject, the image pickup section disposed at a distal end portion of an endoscope; a medical instrument for examination or treatment in the tube cavity based on a reference point, the medical instrument configured to protrude from the distal end portion; a virtual endoscopic image generation section configured to generate a virtual endoscopic image in the tube cavity from a plurality of different line-of-sight positions using three-dimensional image data of the subject that is obtained in advance; an image retrieval section configured to retrieve the virtual endoscopic image highly similar to the endoscopic image of the tube cavity picked up by the image pickup section; a reference-point setting section configured to set a predetermined position near the image pickup section at the distal end portion as the reference point based on the line-of-sight position of the highly similar virtual endoscopic image; and a relative-position calculation section for calculating a relative position of the medical instrument protruded from the distal end portion to the reference point.