PURPOSE To evaluate the level of artery occlusion, degradation periods, tissue response and vessel recanalization of calibrated gelatin sponge particles after segmental renal artery embolization. MATERIALS AND METHODS Superselective embolization of 14 adult rabbits was performed with calibrated gelatin sponge particles (150-350 μm). Two rabbits were killed immediately after the procedure (day 0). One pair of rabbits was killed on each of the following days: 1, 3, 7, 14, 28 and 56. One rabbit from each pair underwent CT angiography before embolization and killing. The pathologic changes of the embolized renal parenchyma and embolic characteristics of calibrated gelatin sponge particles were evaluated histologically and angiographically. RESULTS Calibrated gelatin sponge particles were distally located in interlobular artery with a dense packing on day 0. The level of occlusion paralleled the size of the particles. Partial degradation of the particles was observed on day 3, and complete degradation was observed on day 14. Vessel recanalization was observed through both CTA and histological analysis starting on day 3. Vascular inflammation responding to gelatin sponge particles was mild and subsided with the degradation of the particles. On day 28 and day 56, attenuation of embolized vessels occurred due to marked intimal proliferation, and vascular occlusion developed. CONCLUSIONS Gelatin sponge particles of 150-350 μm produced dense and distal embolization, and were resorbed before day 14 with a mild tissue reaction. Vessel recanalization occurred secondary to the resorption of gelatin sponge particles, but permanent vascular occlusion developed due to marked intimal hyperplasia after day 28.

中文翻译：

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在兔肾脏栓塞模型中校准明胶海绵颗粒的表征。

目的评估分段性肾动脉栓塞后校准明胶海绵颗粒的动脉闭塞程度，降解时间，组织反应和血管再通。材料与方法用明胶海绵颗粒（150-350μm）对14只成年兔进行超选择性栓塞。手术后立即杀死两只兔子（第0天）。在接下来的每一天分别杀死一对兔子：1、3、7、14、28和56。每对兔子中的一只接受栓塞和杀死前的CT血管造影。组织学和血管造影评估了栓塞肾实质的病理变化和明胶海绵颗粒的栓塞特性。结果在第0天，标定的明胶海绵颗粒位于小叶间动脉的远端，并有密集的堆积。阻塞水平与颗粒大小平行。在第3天观察到颗粒的部分降解，并在第14天观察到完全降解。从第3天开始，通过CTA和组织学分析均观察到了血管的再通。对明胶海绵颗粒的血管炎症反应较轻，并随着炎症的减弱而消退。颗粒。在第28天和第56天，由于明显的内膜增生，导致栓塞血管的衰减，并形成了血管闭塞。结论150-350μm的明胶海绵颗粒产生致密的远端栓塞，并在第14天之前被轻度组织反应吸收。