An image processor including image processing circuitry including: a blood flow image obtainer that obtains a blood flow image in which a blood flow area is mapped, the blood flow area indicating blood flow in the examination subject a tomographic image obtainer that obtains a tomographic image including an image of a body tissue inside the examination subject a characteristic obtainer that obtains, based on the blood flow image and the tomographic image, a combination of a first characteristic being a characteristic of the blood flow area itself and a second characteristic indicating a relationship between the blood flow area and the image of a body tissue in the tomographic image and a blood flow evaluator that evaluates a likelihood of the blood flow area indicating a new blood vessel, based on the combination of the first characteristic and the second characteristic of the blood flow area.
