Figure 11a. Type IV tentorial dural AVF. (a) Left external carotid angiogram shows a tentorial dural AVF with leptomeningeal-cortical venous drainage and venous ectasia. (b) Lateral radiograph shows the planned radiation field. Because of the poor general condition of the patient, the AVF was treated with conventional irradiation (total dose, 30 Gy). (c) Left common carotid angiogram obtained 8 months after radiation therapy shows complete obliteration of the tentorial dural AVF.