PT  - JOURNAL ARTICLE
AU  - Ionita, C.N.
AU  - Natarajan, S.K.
AU  - Wang, W.
AU  - Hopkins, L.N.
AU  - Levy, E.I.
AU  - Siddiqui, A.H.
AU  - Bednarek, D.R.
AU  - Rudin, S.
TI  - Evaluation of a Second-Generation Self-Expanding Variable-Porosity Flow Diverter in a Rabbit Elastase Aneurysm Model
AID  - 10.3174/ajnr.A2548
DP  - 2011 Sep 01
TA  - American Journal of Neuroradiology
PG  - 1399--1407
VI  - 32
IP  - 8
4099  - http://www.ajnr.org/content/32/8/1399.short
4100  - http://www.ajnr.org/content/32/8/1399.full
SO  - Am. J. Neuroradiol.2011 Sep 01; 32
AB  - BACKGROUND AND PURPOSE: The self-expanding V-POD is a second-generation flow-diverting device with a low-porosity PTFE patch on a self-expanding microstent. The authors evaluated this device for the treatment of elastase-induced aneurysms in rabbits. MATERIALS AND METHODS: Three V-POD types (A, circumferential patch closed-cell stent [n = 9]; B, asymmetric patch closed-cell stent [n = 7]; and C, asymmetric patch open-cell stent [n = 4]) were evaluated by using angiography, conebeam micro-CT, histology, and SEM. Aneurysm flow modifications were expressed in terms of immediate poststent/prestent ratios of maximum CA volume entering the aneurysm dome tracked on procedural angiograms. Flow modifications were correlated with 4 weeks' follow-up angiographic, micro-CT, histologic, and SEM results. RESULTS: Mechanical stent-deployment difficulties in 4 aneurysms (1 type A; 3 type B) led to suboptimal results and exclusion from analysis. Of the remaining 16 aneurysms, 4-week post-treatment angiograms showed no aneurysm filling in 10 (63%), 3 (∼19%) had no filling with a small remnant neck, and 3 (∼19%) had <0.25 filling. Successfully treated aneurysms (n = 16) demonstrated an immediate poststent/prestent CA maximum volume ratio of 0.13 ± 0.18% (0.0%–0.5%). Favorable contrast-flow modification on immediate angiography after deployment correlated significantly with aneurysm occlusion on follow-up angiography, micro-CT, and histology. The occlusion percentage derived from micro-CT was 96 ± 6.8%. Histology indicated advanced healing (grade ≥3) in the aneurysm dome in 13 of 16 cases. SEM revealed 15 of 16 stents in an advanced state of endothelialization. CONCLUSIONS: This study showed the feasibility and effectiveness of V-POD for aneurysm healing in a rabbit elastase model. AVSasymmetric vascular stentsCAcontrast agentECMextracellular matrixIAintracranial aneurysmPTFEpolytetrafluoroethyleneSEMscanning electron microscopyV-PODvariable-porosity flow diverter