Fluoroscopy method and x-ray ct apparatus

摘要

To make it possible to decrease an X-ray exposure on an operator and to obtain an image of high quality upon fluoroscopy operation. When an X-ray tube is rotated to acquire data, an X-ray radiation dose is set to "0" in a predetermined angular range ( phi 1, to phi 2) including an angle at which the alignment of the X-ray tube -- the operator's hand(h)--the subject (K) is brought about, and the X-ray radiation dose is set to an ordinary one at an angle in a range other than that angular range. The X-ray radiation dose becomes decreased when the operator's hand is directly exposed to the X-ray radiation, and when the X-ray radiation dose becomes increased the operator's hand can be protected from direct exposure to the X-ray owing to the shade of the subject. Thus, an X-ray exposure of an operator can be decreased. Moreover, since the X-ray radiation dose can be increased upon collecting data, it is possible to collect data with a good S/N ratio and obtain an image of high quality. <IMAGE>