Preoperative embolization of meningiomas: its efficacy and histopathological findings.

This report deals with the operative and histopathological findings in 14 meningiomas of 13 patients who were subjected to preoperative embolization. This procedure facilitated the removal of 11 of the 14 tumors and minimized blood loss. In the majority of cases the following histopathological findings were documented: 1) Presence of emboli and thrombi within the tumor and/or dural vessels; 2) associated vascular thrombosis; 3) ischemic changes of the tumor cells; 4) pathologic evidence of infarction with or without inflammatory response, and 5) diffuse or nodular necrosis and surviving tumor cell clusters with an island-like appearance. In two tumors in which the histological diagnosis of typical meningioma was difficult, large necrotic areas comprising over two-thirds of the whole specimens were seen with the naked eye.