MR FLOW QUANTIFICATION USING RACE - CLINICAL-APPLICATION TO THE CAROTID ARTERIES

Real time MR now quantification was performed with real time acquisiti on and evaluation of motion (RACE) in a rigid phantom under steady flo w conditions and in the common carotid arteries of 43 subjects aged 24 -78 years. Hemodynamic information included the intraluminal velocity distribution during the complete cardiac cycle, the distensibility of the arterial wall, and age-dependent changes of the now curves, Systol ic peak velocities of 51 +/- 33 cm/s and time-averaged volume flow rat es of 4.3 +/- 2.0 ml/s were measured in healthy subjects. Flow rates b elow 3.0 ml/s and the observation of abnormal now patterns indicated s tenoses greater than 70% in the region of the bifurcation (sensitivity : 83.3%; specificity: 93.7%; accuracy: 71.4%). Improvements may be ach ieved from a combination with MR angiography, providing both functiona l and morphologic vascular information noninvasively within one observ er-independent examination, MR imaging, therefore, has a strong potent ial for the diagnosis of critical stenoses in symptomatic patients.