Patent ID: 7379526

Claim:
An X-ray CT apparatus comprising: an X-ray area detector comprising one of a multi-row detector and a flat panal; a scanning gantry; and a scanning gantry tilting device configured to tilt the scanning gantry such that X-ray irradiation is started in a state in which an end surface of an X-ray cone beam on front side as viewed in a linearly-moving direction of a helical scan is rendered parallel or substantially parallel to a reconstruction area, said reconstruction area set perpendicular to the linearly-moving direction, wherein the scanning gantry tilting device tilts the scanning gantry such that X-ray irradiation is performed in such a manner that the number of revolutions during an X-ray irradiation period at a helical scan reaches “n+n” (where n: integral number and n: decimal number).