Analysis of the time-velocity curve in phase-contrast magnetic resonance imaging: a phantom study

Comput Assist Surg (Abingdon). 2019 Oct;24(sup2):3-12. doi: 10.1080/24699322.2019.1649066. Epub 2019 Aug 6.

Abstract

The aim of this study was to analyze the characteristics of time-velocity curve acquired by phase-contrast magnetic resonance imaging (PC-MRI) using an in-vitro flow model as a reference for hemodynamic studies. The time- velocity curves of the PC-MRI were compared with Doppler ultrasonography (US) and also compared with those obtained in the electromagnetic flowmeter. The correlation between techniques was analyzed using an electromagnetic flowmeter as a reference standard; the maximum, minimum, and average velocities, full-width at half-maximum (FWHM), and ascending gradient (AG) were measured from time-velocity curves. The correlations between an electromagnetic flowmeter and the respective measurement technique for the PC-MRI and Doppler US were found to be high (mean R2 > 0.9, p < 0.05). These results indicate that these measurement techniques are useful for measuring blood flow information and reflect actual flow. The PC-MRI was the best fit for the minimum velocity and FWHM, and the maximum velocity and AG were the best fit for Doppler US. The PC-MRI showed lower maximum velocity value and higher minimum velocity value than Doppler US. Therefore, PC-MRI demonstrates more obtuse time-velocity curve than Doppler US. In addition, the time- velocity curve of PC-MRI could be calibrated by introducing formulae that can convert each measurement value to a reference standard value within a 10% error. The PC-MRI can be used to estimate the Doppler US using this formula.

Keywords: phase-contrast magnetic resonance imaging; Pulsatile flow; doppler ultrasonography; flow analysis; time-velocity curve.

Publication types

  • Research Support, Non-U.S. Gov't
  • Video-Audio Media

MeSH terms

  • Blood Flow Velocity*
  • Hemodynamics
  • Image Processing, Computer-Assisted
  • Magnetic Resonance Imaging / methods*
  • Phantoms, Imaging
  • Pulsatile Flow
  • Ultrasonography, Doppler