An avalanche-type high definition TV camera as a better detecting system for microangiography using monochromatic synchrotron radiation

We compared an avalanche-type high definition TV camera (HD-TV) system and a conventional image-intensifier-TV camera (II-TV) system coupled to a fluorescent screen for microangiography using monochromatic synchrotron radiation. Nine anesthetized dogs were irradiated while iodine-contrast material was injected into the artery, and the images were detected with the HD-TV system or II-TV system. Both systems visualized small arteries (vasa recta) in the small intestine. Vascular narrowing as branching in vasa recta and their submucosal communications were clearly demonstrated in the HD-TV system, but not in the II-TV system. Spatial resolution determined with a resolution bar chart was 30 /spl mu/m in the HD-TV system, whereas 170 /spl mu/m or more in the II-TV system. The HD-TV system produces a fine microvascular angiogram without losing sensitivity and is useful for evaluating microcirculatory disorders.