Magnetic resonance elastography in assessment on stiffness of aorta

Objective: To investigate the feasibility of magnetic resonance elastography (MRE) technique in evaluation on the mechanical properties of aortic wall in vivo. Methods: MRE was performed to observe abdominal aorta in 5 healthy male volunteers. A passive driver was positioned against anterior abdominal wall. The passive driver produced longitudinal vibrations, which transmitted into abdomen and produced mechanical wave propagation within abdominal aorta. Low amplitude mechanical waves at 60 Hz were generated in the abdomen during imaging. A gradient-echo MRE sequence was used to acquire images showing mechanical wave propagation within abdominal aorta. Results: The propagating wave images were well visualized within the lumen of abdominal aorta in all 5 subjects. The waves propagated longitudinally along the abdominal aorta. The stiffness of aortic wall was evaluated by estimating wavelength. Conclusion: MRE technique has potential for noninvasively assessing stiffness of aorta.