At the same time the imaging end of the cone-beam CT, automatically, to provide a cone-beam X-ray CT apparatus capable of displaying, and its cross section orthogonal to the section including the azimuth angle of the puncture, and a central projection image to the center line of the puncture path To, the rotating means 13 for rotating and opposed to the X-ray source 11 for generating X-rays, the X-ray detector 12, an X-ray detector 12 and X-ray source 11 and projection data of the object and extraction means 310 for extracting a specific portion projection region is a region from a particular region of the subject is taken, the physical quantity of the specific portion projection region is selected that satisfies projection predetermined data, the projection data is selected calculating the azimuth angle of the specific portion when it is taken, and the coordinates of the representative point of the specific portion projection region, the projection data obtained in particular the cross-sectional area through the coordinates of the representative points in parallel azimuthal It includes a specific section reconstructing unit 300 for generating a specific section reconstructed image of the object by back projection operation, and an image display unit 80 for displaying the specific section reconstructed image.コーンビームCTの撮影終了と同時に、自動的に、穿刺の方位角を含む断面とその直交断面と、穿刺パスを中心線とする中心投影像とを、表示し得るコーンビームX線CT装置を提供するために、X線を発生させるX線源11と、X線検出器12と、X線源11とX線検出器12とを対向配置して回転させる回転手段13と、被検体の投影データから、被検体の特定部位が撮影された領域である特定部位投影領域を抽出し、特定部位投影領域の物理量が所定の条件を満たす投影データを選択する抽出手段310と、選択された投影データが撮影されたときの特定部位の方位角と、前記特定部位投影領域の代表点の座標と、を算出し、方位角に平行で代表点の座標を通る特定断面領域で得られた前記投影データを逆投影演算して前記被検体の特定断面再構成像を生成する特定断面再構成手段300と、特定断面再構成像を表示する画像表示手段80と、を備える。
