[Validity testing of time-density curves in determining the degree of arterial stenosis by DSA]

106 patients with a stenosis of the carotid arteries or the common iliac arteries were examined by digital subtraction angiography. The haemodynamic effectiveness of a stenosis was supposed to be measured by time-density curves. Evaluation of time-density curves produced by videodensitometry did not allow to judge the degree of a stenosis of the carotid or the common iliac arteries. Causative for the insufficient accuracy of the results is a patient related change of examination quality. Disturbing factors are reduced cardiac output, moving artifacts, overshadowing of the examined region by air and reduced contrast due to obesity.