title: Comparison of blood velocity measurements between ultrasound Doppler and accelerated phase-contrast MR angiography in small arteries with disturbed flow.
abstract: Ultrasound Doppler (UD) velocity measurements are commonly used to quantify blood flow velocities in vivo. The aim of our work was to investigate the accuracy of in vivo spectral Doppler measurements of velocity waveforms. Waveforms were derived from spectral Doppler signals and corrected for intrinsic spectral broadening errors by applying a previously published algorithm. The method was tested in a canine aneurysm model by determining velocities in small arteries (3-4 mm diameter) near the aneurysm where there was moderately disturbed flow. Doppler results were compared to velocity measurements in the same arteries acquired with a rapid volumetric phase contrast MR angiography technique named phase contrast vastly undersampled isotropic projection reconstruction magnetic resonance angiography (PC-VIPR MRA). After correcting for intrinsic spectral broadening, there was a high degree of correlation between velocities obtained by the real-time UD and the accelerated PC-MRA technique. The peak systolic velocity yielded a linear correlation coefficient of r = 0.83, end diastolic velocity resulted in r = 0.81, and temporally averaged mean velocity resulted in r = 0.76. The overall velocity waveforms obtained by the two techniques were also highly correlated (r = 0.89 ± 0.06). There were, however, only weak correlations for the pulsatility index (PI: 0.25) and resistive index (RI: 0.14) derived from the two techniques. Results demonstrate that to avoid overestimations of peak systolic velocities, the results for UD must be carefully corrected to compensate for errors caused by intrinsic spectral broadening.
authors.affiliation: Medical Physics Department, University of Wisconsin-Madison School of Medicine and Public Health, WI, USA. jjiang2@wisc.edu
authors.forename: Jingfeng
authors.initials: J
authors.lastname: Jiang
authors.forename: Charles
authors.initials: C
authors.lastname: Strother
authors.forename: Kevin
authors.initials: K
authors.lastname: Johnson
authors.forename: Sara
authors.initials: S
authors.lastname: Baker
authors.forename: Dan
authors.initials: D
authors.lastname: Consigny
authors.forename: Oliver
authors.initials: O
authors.lastname: Wieben
authors.forename: James
authors.initials: J
authors.lastname: Zagzebski
mesh_terms: D000054:Acceleration; D000783:Aneurysm / Q000000981:diagnostic imaging* / Q000473:pathology / Q000662:veterinary; D015901:Angiography, Digital Subtraction / Q000379:methods; D000818:Animals; D001158:Arteries / Q000502:physiology*; D016477:Artifacts; D001783:Blood Flow Velocity / Q000502:physiology* / Q000662:veterinary; D003287:Contrast Media; D004285:Dogs; D005260:Female; D021621:Imaging, Three-Dimensional; D018810:Magnetic Resonance Angiography / Q000379:methods*; D018608:Ultrasonography, Doppler / Q000379:methods*
chemical_list: D003287:Contrast Media