In vivo validation of MR pulse pressure measurement in an aortic flow model: preliminary results.
MR imaging experiments were conducted to investigate the feasibility of estimating vascular pulse pressure waveforms from measurements of blood flow rates and vessel cross-sectional area. Blood flow waveforms were measured in the aorta's of three 25-30-kg pigs at multiple imaging sections using phase-contrast velocity imaging. Estimates of pulse pressure were derived from these data by evaluating a model characterizing the relationship between pressure, flow, and the cross-sectional area of a vessel segment. Comparisons between the MR-derived estimates of pressure and those obtained from a micromanometer pressure catheter indicate that accurate measurements (mean error +/- SD = 8.2 +/- 3.4, n = 6) can be obtained using conventional velocity imaging techniques. Optimization of the method will require the application of rapid imaging techniques and the development of strategies for obtaining a more localized measurement. With these improvements, our results suggest that MR-based measurement of pulse pressure and related elastic parameters is feasible.
Urchuk
S N
SN
Department of Medical Biophysics, Sunnybrook Health Science Centre, University of Toronto, Ontario, Canada.
Fremes
S E
SE
Plewes
D B
DB
D000818:Animals; D001013:Aorta, Thoracic / Q000502:physiology*; D001783:Blood Flow Velocity; D001794:Blood Pressure; D005260:Female; D008279:Magnetic Resonance Imaging; D013552:Swine