RADIOGRAPHIC METHOD AND APPARATUS FOR THE VISUALIZATION OF THE INTERIOR OF A BODY PARTICULARLY USEFUL FOR THE VISUALIZATION OF A SUBJECT'S CIRCULATORY SYSTEM

A digital radiographic method and apparatus are described for the visualization of a portion of the circulatory system of a subject by feeding a catheter through a blood vessel while its progress is observed by exposing the respective portion of the subject's body to penetrating radiation, e.g., X-rays. In the described method and apparatus, all the prior positions of the catheter are stored so that all such prior positions visited by the catheter are displayed with each display of its current position. In addition, during the feeding of the catheter through the blood vessel, a substance relatively opaque to the radiation is injected into the blood vessel, whereby the digitized images of the previous catheter visits which are stored and displayed also include the image of the blood vessel and its junctures as revealed by the injected substance.