Automatic accurate non-invasive quantitation of blood flow, cross-sectional vessel area, and wall shear stress by modelling of magnetic resonance velocity data

Objectives:to apply a new, automatic and non-invasive method for quantification of blood flow, dynamic cross-sectional vessel area, and wall shear stress (WSS) by in vivo magnetic resonance velocity mapping of normal subjects.Design:prospective, open study.Materials:six young volunteers.Methods:a three-dimensional paraboloid model enabling automatic determination of blood flow, vessel distensibility and WSS was applied to blood velocity determinations in the common carotid artery. Blood flow was also determined by a manual edge detection method.Results:using the new method, the common carotid mean blood flow was 7.28 (5.61–9.63) (mean (range)) ml/s. By the manual method blood flow was 7.21 (5.55–9.60) ml/s. Mean luminal vessel area was 26% larger in peak systole than in diastole. Mean/peak WSS was 0.82/2.28 N/m2. Manually and automatically determined flows correlated (r2 = 0.998, p<0.0001). WSS and peak centre velocity were associated (r2 = 0.805, p