Hind limb ischemia in rabbit model: T2-prepared versus time-of-flight MR angiography at 3 T.
OBJECTIVE
To prospectively compare various parameters of vessels imaged at 3 T by using time-of-flight (TOF) and T2-prepared magnetic resonance (MR) angiography in a rabbit model of hind limb ischemia.


METHODS
Experiments were approved by the institutional animal care and use committee. Endovascular occlusion of the left superficial femoral artery was induced in 14 New Zealand white rabbits. After 2 weeks, MR angiography and conventional (x-ray) angiography were performed. Vessel sharpness was evaluated visually in the ischemic and nonischemic limbs, and the presence of small collateral vessels was evaluated in the ischemic limbs. Vessel sharpness was also quantified by evaluating the magnitude of signal intensity change at the vessel borders.


RESULTS
The sharpness of vessels in the nonischemic limbs was similar between the TOF and the T2-prepared images. In the ischemic limbs, however, T2-prepared imaging, as compared with TOF imaging, generated higher vessel sharpness in arteries with diminished blood flow (mean vessel sharpness: 44% vs 30% for popliteal arteries, 45% vs 28% for saphenous arteries; P < .001 for both comparisons) and enabled better detection of small collateral vessels (93% vs 36% of vessels, P < .001).


CONCLUSIONS
T2-prepared imaging can facilitate high-spatial-resolution MR angiography of small vessels with low blood flow and thus has potential as a tool for noninvasive evaluation of arteriogenic therapies, without use of contrast material.


BACKGROUND
http://radiology.rsnajnls.org/cgi/content/full/2452062067/DC1.
Korosoglou
Grigorios
G
Russell H. Morgan Department of Radiology and Radiological Science, JHOC 4223, The Johns Hopkins University School of Medicine, 601 N Caroline St, Baltimore, MD, 21287, USA.
Gilson
Wesley D
WD
Schär
Michael
M
Ustun
Ali
A
Hofmann
Lawrence V
LV
Kraitchman
Dara L
DL
Stuber
Matthias
M
D000818:Animals; D006614:Hindlimb / Q000098:blood supply*; D007511:Ischemia / Q000175:diagnosis*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D011817:Rabbits