Reducing the Dose of Contrast Medium in Angiography by Use of a Highly Sensitive Receiver and Synchrotron Radiation System

Abstract

Contrast medium causes side effects such as contrast-induced nephropathy, and the dose of contrast medium is a risk factor in their occurrence. To reduce doses of contrast medium, we developed an angiographic system with high definition and high sensitivity and reviewed its effectiveness. The system entails synchrotron radiation, which is characterized by high photon density and straightness of beam that together result in high resolution, and a high-gain avalanche rushing amorphous photoconductor receiver, which is 100 times more sensitive than conventional charge-coupled device cameras. Diluted contrast medium was administered, and angiography of rat hindlimbs was performed with synchrotron radiation and the high-gain photoconductor receiver. The difference in gray-scale value between the background and contrast medium was calculated. Images were evaluated by counting of arteries. The difference in contrast at low levels was detected with the high-gain photoconductor receiver but not with the charge-coupled device camera. The photon density of synchrotron radiation with the high-gain photoconductor receiver was one-fifth that with the charge-coupled device camera. The high-gain photoconductor receiver had approximately 5 times the sensitivity of the charge-coupled device camera. Use of the synchrotron radiation and high-gain photoconductor receiver makes it possible to perform angiography with an extremely low concentration of contrast medium.