High resolution cine MRI of vessel distension.
OBJECTIVE
We have evaluated the ability of high resolution cine MRI to quantify vessel distension.


METHODS
Gradient echo imaging was used to acquire high resolution, cardiac-triggered imaging of the ascending aorta in normal volunteers to measure changes in the cross-sectional area of the lumen over the cardiac cycle. The effects of temporal resolution, spatial resolution, and the radiofrequency flip angle on the measurements were investigated.


RESULTS
High spatial resolution improved the ability to detect changes in the luminal area. High temporal resolution allowed better tracking of maximal vessel distension. A small flip angle reduced the saturation of slow flow observed in imaging acquired using a large flip angle.


CONCLUSIONS
Our study has demonstrated that high spatial resolution and high temporal resolution can substantially improve the measurement of vessel distension. We have overcome problems of intravoxel dephasing and spin saturation by using high spatial resolution, a short echo time with flow compensation, and a small flip angle.
Chien
D
D
Department of Radiology, University of California at San Francisco.
Saloner
D
D
Laub
G
G
Anderson
C M
CM
D001808:Blood Vessels / Q000033:anatomy & histology* / Q000502:physiology; D003187:Compliance; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009040:Motion Pictures