自制Fe3O4微粒和明胶海绵的肺微循环栓塞效果

背景：有研究表明，小颗粒的栓塞剂易经微导管行栓塞，50-100 μm的颗粒能很好栓塞小动脉，减少侧支循环的产生。 目的：观察自制栓塞剂介入栓塞兔肺微循环的病理改变。 方法：用自制的50，100，150，200，250 μm粒径的Fe3O4微粒、直径500-1 000 μm明胶海绵自制颗粒，对新西兰大白兔行动脉介入肺动脉栓塞，观察其栓塞效果。 结果与结论：数字减影血管造影及病理检测结果显示，50，150，250 μm粒径Fe3O4微粒及明胶海绵自制颗粒均能栓塞兔不同直径肺动脉微循环血管。Fe₃O₄微粒能栓塞兔毛细血管及毛细血管前小动脉，介入栓塞后1-4周兔栓塞血管未见再通，能达到长期栓塞效果，50-250 μm粒径Fe₃O₄微粒能顺利通过微导管行栓塞治疗，且未见明显异位栓塞。明胶海绵自制颗粒能栓塞直径(1 300±348) μm的小动脉，不易通过微导管，在一两周后可被吸收，血管易再通。结果证实，Fe₃O₄微粒具有良好的栓塞效果，栓塞持久、完全、彻底栓塞后血管不易再通，侧支循环不易建立，是良好的肺微循环永久栓塞剂。明胶海绵作为栓塞剂多栓塞于分支小动脉，不能栓塞微循环。

Self-made Fe3O4 versus gelatin sponge embolic agents in rabbit pulmonary microcirculation

BACKGROUND:Studies have shown that small-particle embolic agents can easily perform embolization by micro-catheter, and the arterioles can be embolized well by 50-100 μm particles to reduce collateral circulation generation. OBJECTIVE:To observe the pathological changes following embolizing rabbit pulmonary microcirculation with self-made embolic agents. METHODS:Self-made Fe3O4 fine particles with a size of 50, 100, 150, 200, 250 μm and self-made gelatin sponge with a diameter of 500-1 000 μm were employed for interventional embolism of the pulmonary artery from New Zealand white rabbits. Then, the embolic effect was observed. RESULTS AND CONCLUSION:Angiography and pathological results showed that 50, 150, 250 μm Fe₃O₄ fine particles and gelatin sponge particle could embolize to different-diameter microcirculatory blood vessels. Fe3O4 fine particles could result in the embolization of rabbit capillaries and precapillary arterioles until 1-4 weeks after interventional embolism, indicating that Fe3O4 fine particle had a long-time embolism effect. Fe₃O₄ fine particles could also pass though the microtubule, and no ectopic embolization was visible. Gelatin sponge particles that were unable to pass through the microtubule could block the small arteries with a diameter of (1 300±348) μm. Gelatin sponge particles could be absorbed within 1-2 weeks after embolization. These findings suggest that Fe3O4 particles have good embolic effect that is persistent and complete, and it is difficult to vascular recanalization and establishment of collateral circulation after embolization. Gelatin sponge as an embolic agent is suitable for branches and small arteries rather than the microcirculation.