Radiation image processing apparatus and method thereof

A radiation image processing apparatus which processes non-spiral projection data obtained by radiation imaging performed by rotating a radiation generator and a two-dimensional radiation detector relative to a subject, comprising:

• a reconstruction unit configured to reconstruct the non-spiral projection data into first volume data subjected to an averaging process in a direction of a rotation axis of the rotation and second volume data not subjected to the averaging process;
• a saving unit configured to save the first volume data in memory as first retention data in such a way that pixel data in a plane parallel to a first plane will have successive addresses, save the second volume data in memory as second retention data in such a way that pixel data in a plane parallel to a second plane will have successive addresses, and save the second volume data in memory as third retention data in such a way that pixel data in a plane parallel to a third plane will have successive addresses, wherein the first plane is perpendicular to the direction of the rotation axis, the second plane is parallel to the direction of the rotation axis and the third plane is parallel to the direction of the rotation axis and perpendicular to the second plane;
• a calculation unit configured to perform planar reconstruction calculation using the first retention data to generate a cross section image in the first plane, perform planar reconstruction calculation using the second retention data to generate a cross section image in the second plane and perform planar reconstruction calculation using the third retention data to generate a cross section image in the third plane;
• and
• a display unit configured to display the cross section images obtained by the planar reconstruction calculation.

A radiation image processing method for processing non-spiral projection data obtained by radiation imaging performed by rotating a radiation generator and a two-dimensional radiation detector relative to a subject, comprising:

• a reconstruction step of reconstructing the non-spiral projection data into first volume data subjected to an averaging process in a direction of a rotation axis of the rotation and second volume data not subjected to the averaging process;
• a calculation step of performing planar reconstruction calculation using the first volume data to generate a cross section image in a first plane perpendicular to the direction of the rotation axis and performing planar reconstruction calculation using the second volume data to generate a cross section image in a second plane parallel to the direction of the rotation axis from the second volume data;
• and
• a display step of displaying the cross section images obtained by the planar reconstruction calculation on a display apparatus;
• and
• a changing step of changing the number of tones,
• wherein:
• said reconstruction step generates a plurality of types of first volume data or a plurality of types of second volume data using a plurality of reconstruction filter functions;
• and
• said calculation step uses volume data generated using a reconstruction filter function selected by comparing the number of tones changed in said changing step with a predetermined number of tones.

A radiation image processing apparatus which processes non-spiral projection data obtained by radiation imaging performed by rotating a radiation generator and a two-dimensional radiation detector relative to a subject, comprising:

• a reconstruction unit configured to reconstruct the non-spiral projection data into first volume data subjected to an averaging process in a direction of a rotation axis of the rotation and second volume data not subjected to the averaging process;
• a calculation unit configured to perform planar reconstruction calculation using the first volume data to generate a cross section image in a first plane perpendicular to the direction of the rotation axis and perform planar reconstruction calculation using the second volume data to generate a cross section image in a second plane parallel to the direction of the rotation axis;
• and
• a display unit configured to display the cross section images obtained by the planar reconstruction calculation;
• and
• a changing unit configured to change the number of tones,
• wherein:
• said reconstruction unit generates a plurality of types of first volume data or a plurality of types of second volume data using a plurality of reconstruction filter functions;
• and
• said calculation unit uses volume data generated using a reconstruction filter function selected by comparing the number of tones changed in said changing step with a predetermined number of tones.