Background and purpose Embolization of the middle meningeal artery (MMA) has recently been proposed as an alternative to surgery for treatment of chronic subdural hematoma (SDH), and several case reports have been published supporting its efficacy. It has been suggested that the primary pathologic process in chronic SDH is repeated microhemorrhaging into the subdural collection from fragile neovasculature within the SDH membrane that arises from distal branches of the MMA. Embolization could thus provide a means of eliminating this chronic rebleeding. Materials and methods Images were selected from MMA embolization procedures performed at our institution in order to illustrate the technique and theory behind its efficacy for treatment of chronic SDH. Results Images from MMA angiograms demonstrate the variability of MMA anatomy and help illustrate the importance of avoiding potential ophthalmic collaterals and branches supplying cranial nerves. The findings of irregular wispiness of the distal MMA vasculature, contrast outlining of the SDH membrane on angiography, and homogenous increased density within the SDH on postembolization head computed tomography are described. Conclusion MMA embolization may provide a safe alternative for treatment of chronic SDH, but careful angiographic assessment of MMA anatomy should be performed to avoid potential complications. The findings illustrated here lend support to the theory that the pathologic process of chronic SDH is repeated leakage of blood products from an inflamed, abnormal arterial neovasculature within the SDH membrane that arises from the MMA, and thus selective embolization could provide an effective treatment.
Keywords: Angiography; embolization; middle meningeal artery; minimally invasive; subdural hematoma.