Patent ID: 7564942

Claim:
An X-ray CT apparatus which, using an X-ray source and a multi-slice multi-channel X-ray detector opposing each other, collects X-ray detected data by scanning a subject under the control of a scan control device, and reconstructs an image with an image reconstructing device on the basis of the X-ray detected data, wherein: said X-ray detector has a former half channel part and a latter half channel part which are the same in the number of slices and differ in the coverage in the body axis direction of the subject and in slice thickness; said scan control device selectively performs scan control in a high resolution mode in which the coverage and the slice thickness are smaller or scan control in a high coverage mode in which the coverage and the slice thickness are larger; said image reconstructing device, when a scan in the high resolution mode is performed, generates, from real data obtained by the former half channel part (or the latter half channel part) having a larger coverage, data matched with the coverage and the slice thickness of the latter half channel part (or the former half channel part) having a smaller coverage, combines real data obtained by the latter half channel part (or the former half channel part) having a smaller coverage with the generated data, and reconstructs an image on the basis of those combined data; and said image reconstructing device, when a scan in the high coverage mode is performed, generates, from real data obtained by the latter half channel part (or the former half channel part) having a smaller coverage, data matched with the slice thickness of the former half channel part (or the latter half channel part) having a larger coverage, generates, from real data obtained by the former half channel part (or the latter half channel part) having a larger coverage, data regarding a part where no real data can be obtained by the latter half channel part (or the former half channel part) having a smaller coverage, combines, with these generated data, the real data obtained by a part where the coverage is larger, and reconstructs an image on the basis of the combined data.