Work in progress. Intra-arterial digital subtraction angiography: evaluation in 150 patients.

As part of an ongoing study comparing digital subtraction angiography (DSA) with conventional film-screen angiography, 150 patients were examined with arterial contrast material injections and digital filming techniques alone or combined with conventional angiography. Of 247 injections, the DSA study was good or excellent in 236, approaching the quality of conventional angiography for visualization of vessels greater than 1 mm in size. Advantages included improved vascular detail in selected areas such as the skull base, visualization of minimal contrast concentration in diseased vessels or postoperatively, and imaging of vessels distal to stenoses without the hazards of selective catheterization. DSA permitted rapid positioning under fluoroscopic control, instantaneous viewing of subtracted images, and reduced technologist time and film costs. Contrast material volume was reduced by 40 to 60%, allowing multiple studies in one sitting and study of patients with renal compromise.