Changes in atheroma volume estimated from digitized femoral arteriograms

To evaluate the effects of treatment in patients with cardiovascular risk factors, valid and reproducible methods for assessing changes in atheroma volume are required. We postulated that these changes could be accurately estimated by repeat measurement of the lumen volume of the artery to be studied. With a computer-based technique, the lumen volume of a 20 cm segment of the femoral artery was measured in arteriograms from 107 patients with hypercholesterolemia. Films were digitized with use of a high-resolution scanner, cross-sectional areas were calculated with a slice thickness of 150 microns and the lumen volume was obtained by their integration. The validity of the method was demonstrated in model experiments. An automatic algorithm to correct for changes due to patient positioning was developed and validated in a model experiment. With repeat measurement 10 min and 11 to 13 months apart the coefficients of variation were 2.9 per cent (N = 107) and 6.1 per cent (N = 29), respectively.