title: Evaluation of a second-generation self-expanding variable-porosity flow diverter in a rabbit elastase aneurysm model.
abstract: OBJECTIVE
  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.
  
  
  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.
authors.affiliation: Department of Radiology, School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, USA.
authors.forename: C N
authors.initials: CN
authors.lastname: Ionita
authors.forename: S K
authors.initials: SK
authors.lastname: Natarajan
authors.forename: W
authors.initials: W
authors.lastname: Wang
authors.forename: L N
authors.initials: LN
authors.lastname: Hopkins
authors.forename: E I
authors.initials: EI
authors.lastname: Levy
authors.forename: A H
authors.initials: AH
authors.lastname: Siddiqui
authors.forename: D R
authors.initials: DR
authors.lastname: Bednarek
authors.forename: S
authors.initials: S
authors.lastname: Rudin
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004867:Equipment Design; D002532:Intracranial Aneurysm / Q000139:chemically induced / Q000601:surgery*; D010196:Pancreatic Elastase / Q000008:administration & dosage; D016062:Porosity; D011817:Rabbits; D015607:Stents
chemical_list: D010196:Pancreatic Elastase