Occlusion of lateral aneurysm in common carotid artery of rabbits with flow-diverting stent

Objective: To assess the feasibility of flow-diverting stent in the treatment of lateral aneurysm models in common carotid artery of rabbit. Methods: Ten rabbits were included in our study. Six of nine successful experimental aneurysms were treated with flow-diverting stents, the other three aneurysms were untreated as controls. Angiography was performed immediately and 28 days after the procedure. Aneurysm and stented arteries were removed with animal alive for histopathological examination. Results: Before stent placement angiography of the common artery showed round saccular side-wall aneurysms and complex pattern of flow. Immediately after stent placement the aneurysms were still visible and the stented common carotid arteries remained patent, but the time for the contrast agent in the aneurysm was longer, the complex pattern of flow disappeared. 28 days after stent placement the aneurysms were no longer visible and the stented common carotid arteries remained widely patent. All controlled aneurysms and common carotid arteries have been patent and unchanged for 28 days. Histological analysis indicated that all treated aneurismal pouches were almost filled with thrombus as well as fibrotic reactive scar tissue. Stent wires were found to be located within the vessel wall and encased by an extension of the tunica intima. The endothelium was almost mature at 28 days, and various degrees of degenerate cells were seen under the transmission electron microscopy. Conclusions: The occlusion of lateral aneurysm in common carotid artery of rabbit with flow-diverting stent is safe and effective.