Accuracy and repeatability of fourier velocity encoded M-mode and two-dimensional cine phase contrast for pulse wave velocity measurement in the descending aorta

Abstract

Purpose: To assess the accuracy and repeatability of Fourier velocity encoded (FVE) M-mode and two-dimensional (2D) phase contrast with through-plane velocity encoding (2D-PC) for pulse wave velocity (PWV) evaluation in the descending aorta using five different analysis techniques. Materials and Methods: Accuracy experiments were conducted on a tubular human-tissue-mimicking phantom integrated into a flow simulator. The theoretical PWV value was derived from the Moens-Korteweg equation after measurement of the tube elastic modulus by uniaxial tensile testing (PWV = 6.6 ± 0.7 m/s). Repeatability was assessed on 20 healthy volunteers undergoing three consecutive MR examinations. Results: FVE M-mode PWV was more repeatable than 2D-PC PWV independently of the analysis technique used. The early systolic fit (ESF) method, followed by the maximum of the first derivative (1st der.) method, was the most accurate (PWV = 6.8 ± 0.4 m/s and PWV = 7.0 ± 0.6 m/s, respectively) and repeatable (inter-scan within-subject variation δ = 0.096 and δ = 0.107, respectively) for FVE M-mode. For 2D-PC, the 1st der. method performed best in terms of accuracy (PWV = 6.8 ± 1.1 m/s), whereas the ESF algorithm was the most repeatable (δ = 0.386). Conclusion: FVE M-mode allows rapid, accurate and repeatable central PWV evaluation when the ESF algorithm is used. 2D-PC requires long scan times and can provide accurate although much less repeatable PWV measurements when the 1st der. method is used. © 2010 Wiley-Liss, Inc.