MR-Guided PTA in experimental bilateral rabbit renal artery stenosis and MR angiography follow-up versus histomorphometry.
OBJECTIVE
To assess in vivo 1) MR-guided percutaneous transluminal renal angioplasty (PTRA) in experimental bilateral rabbit renal artery stenosis (RAS); 2) postprocedural follow-up by gadolinium-enhanced MR angiography versus histomorphometry.


METHODS
Fifteen male NZW rabbits of mean weight 4.0 kg (range 3.5-4.2 kg) underwent bilateral RAS induction by combined overdilation-deendothelialization with a gadolinium-filled balloon, passively MR-guided by the artifact of a 0.014-inch guidewire. After 4 weeks the rabbits were randomized into two groups: group A (n = 8) underwent right-sided PTRA for treatment of RAS, group B (n = 7) underwent left-sided PTRA. After another 4 weeks the rabbits were killed to assess by histomorphometry recurrent stenosis and contralateral induction injury stenosis lesions. Each step was preceded by gadolinium-enhanced three-dimensional MR angiography, and the cortex-to-aorta (C/A) signal intensity ratio was calculated.


RESULTS
RAS induction was successful in all cases. Fourteen arteries developed restenosis and 13 only initial stenosis. MR-guided PTRAs were feasible in 22 arteries (73%). For a successful catheterization of the ostium (20 arteries, 66% success rate), 10-25 steps were required. Five to eight steps were required for balloon localization and inflation for each PTRA. The restenosis effect was reflected by a 16% (12%-27%) decrease in C/A values on MR angiograms (p < 0.05).


CONCLUSIONS
MR guidance and MR angiography represent a feasible, less invasive alternative for performing and assessing experimental PTRA in RAS.
Le Blanche
A F
AF
Department of Radiology, Tenon University Hospital, 4 rue de la Chine, F-75970 Paris Cedex 20, France. alain.le-blanche@cfx.ap-hop-paris.fr
Rossert
J
J
Wassef
M
M
Lévy
B
B
Bigot
J M
JM
Boudghene
F
F
D000800:Angioplasty, Balloon / Q000379:methods*; D000818:Animals; D003287:Contrast Media; D004195:Disease Models, Animal; D005682:Gadolinium; D006571:Heterocyclic Compounds; D018810:Magnetic Resonance Angiography; D008297:Male; D009942:Organometallic Compounds; D011817:Rabbits; D012078:Renal Artery Obstruction / Q000473:pathology / Q000628:therapy*; D018709:Statistics, Nonparametric
D003287:Contrast Media; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; C050823:gadolinium 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetate; D005682:Gadolinium