A first generating unit generates a plurality of blood vessel image data sets at the plurality of imaging angles by performing subtraction processing for the plurality of mask image data sets and the plurality of contrast image data sets. A second generating unit generates a blood vessel volume data set including an artery region, a vein region, and a capillary vessel region by performing reconstruction processing for the plurality of blood vessel image data sets. A third generating unit generates a capillary vessel volume data set associated with the capillary vessel region by removing the artery region and the vein region from the blood vessel volume data set. A fourth generating unit generates a capillary vessel image data set by performing three-dimensional image processing for the capillary vessel volume data set.