Histopathological differences of experimental aneurysms treated with bare platinum, fibered, and bioactive coils.

ABSTRACT

PURPOSE: To evaluate the histopathological features of experimental aneurysms embolized with bare platinum, fibered, and bioactive coils. MATERIAL AND METHODS: Twelve experimental aneurysms were constructed in three swine. The aneurysms were divided into four groups and were embolized using a bare platinum coil alone (P group, n = 2), a bioactive coil alone (B group, n = 2), a combination of fibered and bare platinum coils (F/P group, n = 4) and a combination of fibered and bioactive coils (F/B group, n = 4). Histopathological data for all aneurysms recorded at 63 days were analyzed in terms of neointima formation, fibrosis, foreign-body giant-cell infiltration, and organization. RESULTS: Fibrosis was significantly greater in group B compared with that in group F/P (p = .02).　 Inflammation with foreign-body giant-cell infiltration was significantly greater in groups F/P and F/B compared with that in groups P and B (p = .007). CONCLUSION: The present study revealed that the embolic effect of fibered coils was not a thrombus but instead was a foreign-body response in the chronic phase.