| 摘要 |
PROBLEM TO BE SOLVED: To correct the slice thickness without interrupting scanning during spiral scanning in a CT apparatus. SOLUTION: Adjacent different regions 82, 84 within a scanning object are confirmed and a part and interface 86 of them and a transfer region 88 are confirmed and the slice thickness is corrected during scanning so as to obtain redundant data in the transfer region. Especially, in a first operation mode, a variable collimator 72 is used to scan a first region on the basis of first slice thickness. The variable collimator 72 is rotated at the interface between two adjacent regions without interrupting the advance of a table to scan a second region on the basis of second slice thickness. When the slice thickness is changed, X-ray beam 80 having the second slice thickness sweeps the collimator 72 so as to re-scan a part of the first region within the transfer region 88. Further, to be concrete, the collimator 72 is swept so that the transfer region 88 is scanned on the basis of both slice thicknesses. |
