Micro-Arteriography

A technique is described for the radiography of sections of organs injected with radio-opaque material. Success depends on two factors, i.e., a photographic film that is virtually grainless, and the use of radiations of long wave length. These radiographs are highly selective, showing virtually nothing except the radio-opaque material in the vessels. They can be magnified by simple enlargement onto ordinary photographic paper by about 10 to 15 diameters, giving the vascular pattern as a whole and thus forming a link between the macroscopic and the microscopic methods of study. Capillaries, however, are not seen at a magnification of × 15, but if photo-micrographs are taken of the radiograph, a magnification of × 50 gives the detail of capillaries and of every injected vessel. There is so much detail in these photo-micrographs that they can be magnified × 5 in the enlarging apparatus direct onto photographic paper of adequate size, giving a total enlargement of × 250.