PROBLEM TO BE SOLVED: To always warrant projection data required for the reconstruction of an image.SOLUTION: When the section of projection data used for the reconstruction is decided from electrocardiogram information and an image corresponding to a predetermined electrocardiogram phase is reconstructed according to the projection data corresponding to two or more heart beats, control is performed so as to extend the exposure period of X rays or a period, in which X-ray intensity is strong, during a period of at least one heart beat among two or more heart beats used for the reconstruction of the image. For example, control is performed so as to extend the exposure period of the X rays during a period of the first heart beat among two or more heart beats used for the reconstruction of the image.COPYRIGHT: (C)2009,JPO&INPIT【課題】画像の再構成に必要な投影データを常に保証すること。【解決手段】心電情報に基づいて、再構成に用いる投影データの区間を決めて、複数の心拍に対応する投影データを合わせて所定の心電位相に対応する画像を再構成する際に、画像の再構成に用いる複数の心拍のうちの少なくとも1つの心拍期間で、X線の曝射期間、または、X線強度の強い期間を拡張するように制御する。例えば、画像の再構成に用いる複数の心拍のうちの最初の心拍期間で、X線の曝射期間を拡張するように制御する。【選択図】 図1
