VELOCITY-ENCODED, PHASE-DIFFERENCE CINE MRI MEASUREMENTS OF CORONARY-ARTERY FLOW - DEPENDENCE OF FLOW ACCURACY ON THE NUMBER OF CINE FRAMES

Phase-contrast magnetic resonance imaging (PC-MRI) can be used to prod uce multiframe cine now images of the coronary arteries. Accurate coro nary flow measurement requires the elimination of respiratory motion a rtifacts using k-space segmentation to acquire the data in a single br eath-hold, However, the duration of the breath-hold is proportional to the number of cine frames, In the present study, the number of cine f rames was varied and the accuracies of the coronary now measurements w ere assessed using perivascular US. For the range of flows studied (2 ml/min to 147 ml/min), the correlation coefficients for PC-MRI and US increased (.70-.98) and the limits of agreement improved (+/-45 ml . m in(-1) to +/-10 ml . min(-1)) as the number of cine frames increased f rom one to six. The results suggest that the accuracy of breath-hold c ine PC-MRI measurements of coronary artery now improves as the number of cine frames increases.