X-Ray CT apparatus and method of controlling the same

An X-ray CT apparatus comprising:

• an X-ray tube;
• an X-ray detector that has first and second ends in a direction perpendicular to a body axis of an object and an X-ray irradiation axis, the first end being closer to the X-ray irradiation axis than the second end and the second end being farther from the X-ray irradiation axis than the first end;
• a scanning controller that obtains projection data in a first direction by moving the X-ray tube and the X-ray detector by a first rotational angle, wherein when the object is not within the range of X-ray detection from the first direction, the scanning controller obtains projection data in a second direction by moving the X-ray tube and the X-ray detector by a second rotational angle, respectively;
• an image processor that superimposes the projection data corresponding to the first and second directions and produces an image for scan setting when the projection data in the second direction is obtained, wherein the image processor forms the image for scan setting from the projection data in the first direction when the projection data in the second direction is not obtained;
• and
• a scanner that sets a scanning plan based on the image for scan setting to scan the object based on the scanning plan.