title: Endovascular image-guided treatment of in-vivo model aneurysms with asymmetric vascular stents (AVS): evaluation with time-density curve angiographic analysis and histology.
abstract: In this study, we compare the results obtained from Time-Density Curve (TDC) analysis of angiographic imaging sequences with histological evaluation for a rabbit aneurysm model treated with standard stents and new asymmetric vascular stents (AVS) placed by image-guided endovascular deployment. AVSs are stents having a low-porosity patch region designed to cover the aneurysm neck and occlude blood flow inside. To evaluate the AVSs, rabbits with elastase-induced aneurysm models (n=20) were divided into three groups: the first (n=10) was treated with an AVS, the second (n=5) with a non-patch standard coronary stent, and third was untreated as a control (n=5). We used TDC analysis to measure how much contrast media entered the aneurysm before and after treatment. TDCs track contrast-media-density changes as a function of time over the region of interest in x-ray DSA cine-sequences. After 28 days, the animals were sacrificed and the explanted specimens were histologically evaluated. The first group showed an average reduction of contrast flow into the aneurysm of 95% after treatment with an AVS with fully developed thrombus at 28 days follow-up. The rabbits treated with standard stents showed an increase in TDC residency time after treatment and partial-thrombogenesis. The untreated control aneurysms displayed no reduction in flow and were still patent at follow-up. The quantitative TDC analysis findings were confirmed by histological evaluation suggesting that the new AVS has great potential as a definitive treatment for cerebro-vascular aneurysms and that angiographic TDC analysis can provide in-vivo verification.
authors.affiliation: Toshiba Stroke Research Center-Division of Radiation Physics, SUNY-University at Buffalo, 3435 Main Street, Buffalo, NY, 14214, USA.
authors.forename: A
authors.initials: A
authors.lastname: Dohatcu
authors.forename: C N
authors.initials: CN
authors.lastname: Ionita
authors.forename: A
authors.initials: A
authors.lastname: Paciorek
authors.forename: D R
authors.initials: DR
authors.lastname: Bednarek
authors.forename: K R
authors.initials: KR
authors.lastname: Hoffmann
authors.forename: S
authors.initials: S
authors.lastname: Rudin