Patent ID: 7074225

Claim:
A medical drilling machine, comprising: a drive shaft held in place in a rotatable fashion, gripping a drill bit by means of a chuck provided to an end of the drive shaft; a casing constituted of X-ray transparent material, being capable of housing the drive shaft, a force transfer mechanism for transferring rotational force to the drive shaft; and a first guide and a second guide constituted of X-ray opaque material are fixed at given distances from each other along an axial direction of the drive shaft inside the casing, wherein the first guide and the second guide are arranged coaxially along an axial center of the drive shaft and are formed in mutually different shapes; and X-rays are radiated along a direction of an ideal axial line traveled by the drill bit, such that a slant direction of the drill bit with respect to the ideal axial line can be observed from any relative misalignment of, and the mutually different shape of, the first and the second guides.