髄膜腫に対する術前塞栓術　−塞栓効果評価と病理診断−

抄録

Preoperative embolization (POE) of meningioma is a widely adopted adjunctive procedure in favor of decrease of the intraoperative bleeding, softening of the tumor and shortening of the operative time. It is indicated not only for large and/or hypervascular meningiomas, but also for those located at the skull base; however, the evidence of its usefulness has not been established, although its favorable effects have been shown on contrast-enhanced or arterial spin labeling MRI.

To date, different embolic materials have been used, such as particles, liquid and metallic coils, which should be selected after careful assessment of the feeding arteries, considering the features of each embolic material. On histopathological diagnosis, POE frequently induces necrosis, regenerative atypia and compensatory proliferative activity in the tumor, which may have the potential for overgrading inherently benign meningiomas (WHO grade I) as atypical (WHO grade II). This concern has influenced the definition of atypical meningioma in the WHO classifications. This review describes the current status of POE of meningioma and the pathological considerations in the diagnosis of embolized meningiomas.