Comparison of observer and videodensitometric measurements of simulated coronary artery stenoses

To test the applicability of an automated vessel measurement technique to coronary arteriography, a videodensitometric method with caliper measurements on digital subtraction images of a moving coronary artery phantom was compared. Percent diameter stenosis was determined by both methods, revealing a twofold improvement in reproducibility with the videodensitometric method, with percent stenosis being determined within +/- 10% for two different iodine concentrations injected during continuous flow into the simulated coronary arteries. Absolute diameters were also measured by the videodensitometric method, showing a high degree of correlation between measured and true diameter for vessels between 0.5-3.0 mm.