PROBLEM TO BE SOLVED: To make reduction effect of an exposure dose effective when a filter is used.SOLUTION: An X-ray computerized tomography apparatus includes: a gantry 1 having an X-ray tube rotatable around a subject and an X-ray detector a bed 2 having a top plate movable for three axes of the rotation axis of the X-ray tube and two axes perpendicular to the rotation axis a control part 30 for controlling the movement of the top plate on the basis of the deviation relative to the three axes between the center position of a region of interest about the subject and the rotation position of the X-ray tube and an image reconstructing part 36 for reconstructing an image on the basis of the output of the X-ray detector. When the center position of the region of interest matches the center position of the X-ray tube and when the center position of the region of interest does not match the rotation position of the X-ray tube due to the movement limit of the top plate, the reconstruction center by the reconstructing part is brought to match the center position of the region of interest.COPYRIGHT: (C)2013,JPO&INPIT【課題】フィルタを使った場合に被曝線量の低減効果を実効的なものとすること。【解決手段】X線コンピュータ断層撮影装置は、被検体の周囲を回転自在なX線管とX線検出器を有する架台1と、X線管の回転軸と回転軸に直交する2軸との3軸に関し移動自在な天板を有する寝台2と、被検体に関する関心領域の中心位置と前記X線管の回転中心との間の前記3軸に関するズレに基づいて天板の移動を制御する制御部30と、X線検出器の出力に基づいて画像を再構成する画像再構成部36とを具備し、関心領域の中心位置がX線管の回転中心に一致するとき及び天板の移動限界により関心領域の中心位置が前記X線管の回転中心に一致しないとき、再構成部による再構成中心は関心領域の中心位置に一致される。【選択図】図1
