Department of Neuroradiology, University Hospital Heidelberg, Heidelberg, Germany.
Clinic for Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg, Germany.
PLoS One. 2018 Jul 9;13(7):e0198911. doi: 10.1371/journal.pone.0198911. eCollection 2018.
The present study compared standard computed tomography (CT) and histopathological findings after endovascular embolization using a prototype of inherently radiopaque 40μm-microspheres with both standard 40μm-microspheres and iodized oil in a porcine liver model.
Twelve pigs were divided into six study groups, of two pigs each. Four pigs were embolized with iodized oil alone and four with radiopaque microspheres; two animals in each group were sacrificed at 2 hours and two at 7 days. Two pigs were embolized with radiopaque microspheres and heparin and sacrificed at 7 days. Two pigs were embolized with standard microspheres and sacrificed at 2 hours. CT was performed before and after segmental embolization and before sacrifice at 7 days. The distribution of embolic agent, inflammatory response and tissue necrosis were assessed histopathologically.
Radiopaque microspheres and iodized oil were visible on standard CT 2 hours and 7 days after embolization, showing qualitatively comparable arterial and parenchymal enhancement. Quantitatively, the enhancement was more intense for iodized oil. Standard microspheres, delivered without contrast, were not visible by imaging. Radiopaque and standard microspheres similarly occluded subsegmental and interlobular arteries and, to a lesser extent, sinusoids. Iodized oil resulted in the deepest penetration into sinusoids. Necrosis was always observed after embolization with microspheres, but never after embolization with iodized oil. The inflammatory response was mild to moderate for microspheres and moderate to severe for iodized oil.
Radiopaque 40μm-microspheres are visible on standard CT with qualitatively similar but quantitatively less intense enhancement compared to iodized oil, and with a tendency towards less of an inflammatory reaction than iodized oil. These microspheres also result in tissue necrosis, which was not observed after embolization with iodized oil. Both radiopaque and standard 40μm-microspheres are found within subsegmental and interlobar arteries, as well as in hepatic sinusoids.
本研究比较了使用原型固有不透射线的 40μm 微球与标准的 40μm 微球和碘油在猪肝脏模型中进行血管内栓塞后的标准计算机断层扫描（CT）和组织病理学发现。
将 12 头猪分为 6 个研究组，每组 2 头。4 头猪单独用碘油栓塞，4 头猪用不透射线的微球栓塞；每组各有 2 只动物在栓塞后 2 小时和 7 天处死，2 只动物用放射性微球和肝素栓塞，在 7 天处死。2 头猪用标准微球栓塞，2 小时后处死。栓塞前、栓塞后及 7 天前进行 CT 检查。通过组织病理学评估栓塞剂的分布、炎症反应和组织坏死。
在栓塞后 2 小时和 7 天，标准 CT 可显示不透射线的微球和碘油，显示出定性上相似但定量上增强更明显的动脉和实质增强。没有造影剂的标准微球在影像学上不可见。不透射线和标准微球同样阻塞亚段和小叶间动脉，程度较轻的还有窦状隙。碘油导致窦状隙的渗透最深。栓塞微球后总是观察到坏死，但栓塞碘油后从未观察到。微球的炎症反应为轻度至中度，碘油为中度至重度。
与碘油相比，标准 CT 上可观察到具有定性相似但定量上增强较弱的放射性 40μm 微球，且炎症反应的程度低于碘油。这些微球也会导致组织坏死，而碘油栓塞后不会观察到这种情况。放射性和标准的 40μm 微球均位于亚段和小叶间动脉内，以及肝窦内。
