Quantification of aortic stiffness using MR elastography and its comparison to MRI-based pulse wave velocity.
OBJECTIVE
To determine the correlation in abdominal aortic stiffness obtained using magnetic resonance elastography (MRE) (μ(MRE)) and MRI-based pulse wave velocity (PWV) shear stiffness (μ(PWV)) estimates in normal volunteers of varying age, and also to determine the correlation between μ(MRE) and μ(PWV).


METHODS
In vivo aortic MRE and MRI were performed on 21 healthy volunteers with ages ranging from 18 to 65 years to obtain wave and velocity data along the long axis of the abdominal aorta. The MRE wave images were analyzed to obtain mean stiffness and the phase contrast images were analyzed to obtain PWV measurements and indirectly estimate stiffness values from the Moens-Korteweg equation.


RESULTS
Both μ(MRE) and μ(PWV) measurements increased with age, demonstrating linear correlations with R(2) values of 0.81 and 0.67, respectively. Significant difference (P ≤ 0.001) in mean μ(MRE) and μ(PWV) between young and old healthy volunteers was also observed. Furthermore, a poor linear correlation of R(2) value of 0.43 was determined between μ(MRE) and μ(PWV) in the initial pool of volunteers.


CONCLUSIONS
The results of this study indicate linear correlations between μ(MRE) and μ(PWV) with normal aging of the abdominal aorta. Significant differences in mean μ(MRE) and μ(PWV) between young and old healthy volunteers were observed.
Department of Biomedical Engineering, Ohio State University, Columbus, Ohio, USA.
Anirudh R
AR
Damughatla
Brian
B
Raterman
Travis
T
Sharkey-Toppen
Ning
N
Jin
Orlando P
OP
Simonetti
Richard D
RD
White
Arunark
A
Kolipaka
D000293:Adolescent; D000328:Adult; D000368:Aged; D001012:Aorta, Abdominal / Q000503:physiopathology; D054459:Elasticity Imaging Techniques / Q000379:methods*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D063177:Pulse Wave Analysis / Q000379:methods*; D015203:Reproducibility of Results; D059289:Vascular Stiffness / Q000502:physiology*; D055815:Young Adult
PWV; aortic MRE; aortic stiffness; magnetic resonance elastography (MRE)