PURPOSE: To facilitate a command input by sharing a cursor position information used for two scout images to allow a cursor position on each scout image to move on corresponding axis together with the other cursor position when determining a scanning center using a X-ray transparent image.

CONSTITUTION: A cursor data storing device 13 which stores a cursor position information indicating the cursor position to be displayed to determine a scanning center on the X-ray transparent image, X-ray transparent images in x and y directions are created by X and Y scout X-ray transparent image processing means 11 and 12, and each cursor is displayed on the X-ray transparent image according to the cursor position information stored in the storing device 13. A cursor position information in the cursor data storing device 13 is updated by a control means 14 according to the cursor moving instruction from an input means 15, and a scanning center is determined according to the position information of the cursor data storing device 13 to control the X-ray tomographic imaging.