An inner wall extractor extracts the inner wall of a vital tissue based on medical image data. An outer wall extractor extracts the outer wall of the vital tissue based on the medical image data. A first raised portion calculator obtains information including the presence of a first raised portion in which the inner wall of the vital tissue is raised inward, based on the extracted inner wall of the vital tissue. A second raised portion calculator obtains information including the presence of a second raised portion in which the outer wall of the vital tissue is raised outward, based on the extracted outer wall of the vital tissue. A display controller superimposes the information of the first raised portion and the information of the second raised portion on an image of the vital tissue, and causes the image to be displayed on a display.