PROBLEM TO BE SOLVED: To provide an X-ray computed tomography apparatus capable of preventing interference between a subject and the gantry and at the same time reducing unnecessary exposure of the subject to radiation.SOLUTION: An X-ray computed tomography apparatus 1 according to the embodiment comprises: a gantry 11 having an X-ray tube and an X-ray detector disposed facing each other across an opening and movable relative to an examination room floor surface to image a subject with X-rays illuminated from the X-ray tube a storage circuit 55 for storing information of a first boundary indicative of an outer rim of an imaging field inside the opening and information of a second boundary located between the first boundary and an inner surface of the opening to prevent interference between the subject and the gantry and a control circuit for controlling the X-ray tube to stop illumination of X-rays based on a relative positional relationship between a scan target area of the subject and the first boundary or for controlling the gantry to stop movement of the gantry based on a relative positional relationship between a non-scan target area of the subject and the second boundary.SELECTED DRAWING: Figure 1COPYRIGHT: (C)2017,JPO&INPIT【課題】被検体と架台とを干渉させることなく、かつ被検体に対する不要被曝を低減可能なX線コンピュータ断層撮影装置の提供。【解決手段】本実施形態に係るX線コンピュータ断層撮影装置1は、開口部を挟んでX線管およびX線検出器を有し、X線管から照射されるX線によって被検体を撮影するために検査室の床面に対して相対的に移動可能な架台11と、開口部の内部において撮像視野の外縁を示す第1境界に係る情報と、第1境界と前記開口部の内面との間であって被検体と架台との干渉を防ぐための第2境界に係る情報とを記憶する記憶回路55と、被検体のスキャン対象領域と第1境界との相対的な位置関係に基づいて、X線の照射を停止するようにX線管を制御する、又は被検体の非スキャン対象領域と第2境界との相対的な位置関係に基づいて、架台の移動を停止させるように架台を制御する制御回路と、を具備する。【選択図】 図1
