O-058 Preclinical validation of the ReSolvTMstent: a primarily bioresorbable flow diverter for aneurysm treatment

Abstract

<h3>Introduction/Purpose</h3> Existing metal flow-diverting stents are limited in their use mainly for sidewall aneurysms and restrict re-treatment options should the aneurysm fail to occlude. In this study, we sought to pre-clinically validate a novel hybrid polymer-metal flow-diverting stent (‘ReSolv^TM’) in terms of <i>in vivo</i> safety and efficacy, deployment in multiple aneurysm types, and an ability to employ adjunctive or re-treatment techniques typically unavailable for metal stents. <h3>Materials and Methods</h3> The ReSolv^TM stent was deployed in 30 rabbit models, including 24 aortas (with up to 18 months of follow-up) and 6 elastase-induced saccular aneurysms (with at least 6 months of follow-up). Optical coherence tomography (OCT) was used to characterize neointima formation while angiography was used to evaluate parent vessel/jailed side branch patency, as well as aneurysm occlusion at follow-up time points. Patient-specific models of ophthalmic, posterior communicating, cavernous, and basilar tip aneurysms were used to study deployment characteristics, wall apposition (by 3D AngioCT), and mesh crossability of the BRS. <h3>Results</h3> In animal models, OCT showed smooth neointima formation over the stent in as early as 7 days, and all parent vessels (30/30) and angiographically visible jailed side branches (58/58) were patent at follow-up. O’Kelly-Marotta scores at a mean of 7.5 months indicated aneurysm occlusion or near-occlusion in 5/6 (83%) animals. The stent was successfully deployed using the push-pull technique in patient-specific aneurysm models with good wall apposition, and with an ability to shape the stent to improve neck coverage of bifurcation aneurysms. Microcatheter access to the aneurysm could be obtained across the mesh of the stent for coiling after flow diversion. <h3>Conclusions</h3> The ReSolv^TM stent demonstrates safety and effectiveness as a stand-alone flow diverter in animal models. The device is uniquely versatile in its potential ability to treat both sidewall and bifurcation aneurysms, and by permitting microcatheter access across the mesh for adjunctive coiling or future re-treatment, thereby expanding therapeutic strategies in the treatment of brain aneurysms. <h3>Disclosures</h3> <b>E. Rezabeigi:</b> 5; C; Fluid Biomed. <b>M. Eesa:</b> 4; C; Fluid Biomed. <b>J. Wong:</b> 4; C; Fluid Biomed. <b>A. Mitha:</b> 1; C; Stryker Neurovascular, Fluid Biomed. 2; C; Cerus Endovascular. 4; C; Fluid Biomed.