Provided with: a region extraction unit having a time information acquisition means that acquires time information pertaining to the imaging time of a medical image from input volume data, an imaging time phase estimation means that estimates the imaging time phase of the medical image on the basis of the acquired time information, a region extraction processing mode determination means that determines, in accordance with the estimated imaging time phase, a region extraction processing mode comprising a region extraction algorithm for extracting a region that is the target of image processing from the medical image and the parameters necessary for executing the region extraction algorithm, and a region extraction processing execution means that executes region extraction processing on the input volume data by means of the determined mode for region extraction processing； and an image processing algorithm execution unit that executes a specific image processing algorithm on the volume data of the extracted region.
