A one-dimensional velocity technique for NMR measurement of aortic distensibility

✍ Scribed by Christopher J. Hardy; Bradley D. Bolster; Elliot R. McVeigh; William J. Adams; Elias A. Zerhouni

• Publisher: John Wiley and Sons
• Year: 1994
• Tongue: English
• Weight: 887 KB
• Volume: 31
• Category: Article
• ISSN: 0740-3194
• DOI: 10.1002/mrm.1910310507

✦ Synopsis

Abstract

A technique is presented for rapidly and noninvasively determining aortic distensibility, by NMR measurement of wave velocity in the aorta. A two–dimensional NMR selective‐excitation pulse is used to repeatedly excite a cylinder of magnetization in the aorta, with magnetization read out along the cylinder axis each time. A toggled bipolar flow‐encoding pulse is applied prior to readout, to produce a one‐dimensional phase‐contrast flow image. Cardiac gating and data interleaving are employed to improve the effective time resolution to 2 ms. Wave velocities are determined from the slope of the leading edge of flow measured on the resulting M‐mode velocity image. The technique is sensitive over a range of distensibilities from 10^−8^ to 10^−3^ m s^2^/kg. The average value in the descending thoracic aorta in seven normal subjects was found to be 4.8 × 10^−5^ m s^2^/kg, with a significant inverse correlation with age.