Spontaneous disappearance of a huge cerebral arteriovenous malformation: case report

A case of spontaneous disappearance of a cerebral arteriovenous malformation (AVM) is reported. A 59-year-old woman, who had been diagnosed as having a huge AVM in the left occipital lobe 6 years before and who was monitored without treatment, complained of a sudden headache and vomiting. Computed tomography revealed an acute subdural hematoma, intracerebral hematoma, and subarachnoid hemorrhage, for which a craniotomy was performed. Cerebral angiograms performed 9 days after the operation demonstrated a decrease in the size of the AVM. Repeated cerebral angiograms performed a month later demonstrated complete disappearance of the AVM. Follow-up angiograms performed 19 months after hemorrhage confirmed complete disappearance of the AVM. Spontaneous disappearance is known to occur occasionally in small AVMs but rarely in huge ones such as the one presented here. Several possible mechanisms for spontaneous disappearance of AVMs are discussed.