Comparison of digital subtraction arteriography and conventional film screen subtraction arteriography for neuroradiology.

Sixty-nine patients with 91 separate abnormal findings were studied by both intra-arterial digital subtraction arteriography (ADSA) and conventional film screen subtraction arteriography (CFSA) in the same projection, with the same magnification. Digital subtraction arteriography has distinct advantages over CFSA in the form of reduced contrast utilization, better patient tolerance of arteriography because of reduced contrast concentration, superior contrast resolution, and rapid, on-line visualization of the abnormalities. Digital subtraction arteriography is limited by its availability in only a single plane, by decreased spatial resolution which affected the image quality for intracranial blood vessels at an image intensifier (I.I.) field of 12 inches, and by relatively limited field of view both intracranially and extracranially for I.I. fields of 6 and 9 inches.