The development and use of digital subtraction angiography.

The technique of radiographic subtraction was first described in 1935 (Ziedses des Plantes, 1935), although the first English language paper on the subject did not appear until 27 years later (Hanafee & Stout, 1962). This commented that the technique provided an economical photographic method of reducing the confusion of overlapping bony structures in angiographic studies. The advantages of radiographic subtraction can be summarized as (a) providing image enhancement and (b) improving and bringing out detail in areas hidden by overlying bone or poor contrast. These features may therefore save the situation when the density of contrast medium is insufficient to show a lesion (Leeds, 1974). Previously, intravenous injections of contrast medium had been used to show the aorta and other arteries (Steinberg et al, 1959). Digitization of images was introduced experimentally (Meyers et al, 1963), with the aim of automating the reading of radiographs. Manipulation of digitized information became widely used when ...