[Spontaneous regression of cerebral arterio-venous malformation following major artery thrombosis proximal to dominant feeders: a case report].

A rare case of spontaneous regression of cerebral arterio-venous malformation (AVM) is reported. A 76-year-old male was admitted to Juzen General Hospital due to generalized convulsion on August 24, 1987. On admission, results of physical and neurological examinations were normal. Plain CT scans showed an iso-density lesion with a slightly high density spot in the left frontal lobe, and enhanced CT scans showed multiple, irregularly tubular enhancements in the lesion. Left carotid angiogram (CAG) demonstrated an arteriovenous malformation (AVM) in the left frontal lobe, which was fed by the left ACA and MCA and drained by the ascending cerebral vein and superficial Sylvian vein. There was also an anterior communicating artery aneurysm. At the patient's request, he was treated conservatively and was discharged without neurological deficit. Though he continued to take anticonvulsants thereafter, he felt weakness or numbness of the right extremities once a year. Five years after the first admission, he developed sudden onset of right hemiparesis, aphasia and consciousness disturbance. On admission, his platelet aggregation function was elevated. At this time, enhanced CT scans did not show any enhanced area in the left frontal lobe where AVM had been found previously. T2-weighted magnetic resonance image showed a mixed intensity area without any flow void phenomenon suggesting thrombosis of the nidus. Left CAG demonstrated occlusion of the A1-A2 junction of the anterior cerebral artery and disappearance of the AVM. He was treated conservatively again, and was discharged without neurological deficit.(ABSTRACT TRUNCATED AT 250 WORDS)