| 摘要 |
PROBLEM TO BE SOLVED: To provide an X-ray CT apparatus capable of optimizing its tube voltage and tube current. SOLUTION: Based on scout data acquired by scout photography and a tube voltage V1 of an X-ray tube, a tube current I1 of the X-ray tube is calculated so that an image of a required picture quality level SD can be acquired when a subject is scanned with the tube voltage V1 combined (S103). Then a tube voltage V2 (<V1) and a tube current I2, which practically offer an image of the same picture quality as the one when the subject is scanned with the tube voltage V1 and the tube current I1, are set (S104-S106). When the tube voltage is lowered at a constant noise, a contrast noise ratio (CNR) of the image is improved, and when the tube voltage is lowered at a constant CNR, exposure is lowered. COPYRIGHT: (C)2012,JPO&INPIT |
