Cerebellar hemorrhage and subsequent venous infarction followed by incomplete transvenous embolization of dural carotid cavernous fistulas: a rare complication: case report.

Endovascular therapy for dural carotid cavernous fistulas (CCFs) is generally accepted to be safe and effective. The authors report a rare complication of hemorrhage and subsequent venous infarcts of the pons and cerebellum after transvenous embolization. This 41-year-old man presented with a severe left frontal headache, congestion of the left conjunctiva, blurred vision, and photophobia. Cerebral angiography demonstrated a right dural CCF. The patient underwent transvenous embolization of the cavernous sinus but had the initial complication of cerebellar hemorrhage. One month later, he developed progressive dizziness, ataxia, and right-sided weakness. Magnetic resonance imaging revealed severe cerebellar and pontine edema. The cause was a residual fistula combined with delayed occlusion of the inferior petrosal sinus. The fistula was obliterated after repeated embolizations. The patient's symptoms gradually resolved, and there was no evidence of recurrence during the 4-year follow-up period. Incomplete transvenous embolization of a dural CCF can result in life-threatening vascular complications due to redistribution of shunt flow. Early recognition of redistributed drainage and preventive placement of coils at the origin of draining veins during the procedure could avert this rare complication.