MR elastography of the human abdominal aorta: a preliminary study.
OBJECTIVE
To investigate the feasibility of using MR elastography (MRE) for the evaluation of the stiffness of in vivo aortic wall.


METHODS
To validate the experimental approach for imaging the aorta in vivo, a gel phantom with an embedded porcine aorta was imaged in the presence of fluid flow within the aorta. The potential changes in the elasticity of the vessel wall with changes in pressure were investigated. The feasibility of performing MRE of abdominal aorta was assessed in five volunteers (age, 22-40 years; body mass index, 21.5-25.2 kg/m(2) ). The pulse-gated cine MRE technique was used to study the wave propagation along the aorta throughout the cardiac cycle and provide estimates of aortic stiffness in diastole.


RESULTS
In the phantom study, the wave propagation was well visualized within the porcine aorta embedded in the gel phantom. An increase of the Young's modulus-wall thickness (E*t) product with the increase in static pressure was observed. In the in vivo study, the waves were well visualized within the lumen of abdominal aorta in the five volunteers in diastolic phase, but they were not well visualized during systole.


CONCLUSIONS
MRE is feasible for noninvasively assessing the stiffness of the abdominal aorta and merits further investigation.
Radiology Department, Mayo Clinic, Rochester, Minnesota, USA; Radiology Department, Beijing Anzhen Hospital, Capital Medical University, Beijing, China.
Lei
L
Xu
Jun
J
Chen
Kevin J
KJ
Glaser
Meng
M
Yin
Phillip J
PJ
Rossman
Richard L
RL
Ehman
D000328:Adult; D000818:Animals; D001012:Aorta, Abdominal / Q000033:anatomy & histology* / Q000502:physiology*; D055119:Elastic Modulus / Q000502:physiology; D054459:Elasticity Imaging Techniques / Q000295:instrumentation / Q000379:methods*; D005240:Feasibility Studies; D006801:Humans; D008297:Male; D019047:Phantoms, Imaging; D010865:Pilot Projects; D033081:Shear Strength / Q000502:physiology; D013314:Stress, Mechanical; D013552:Swine; D059289:Vascular Stiffness / Q000502:physiology; D055815:Young Adult
MRI; aorta; elastography; stiffness