[A case of large basal ganglia AVM totally removed by staged operation]

Large basal ganglia AVMs have been deemed inoperable because of their location in critical structures. Nonetheless, the unfavorable natural history of an untreated ruptured AVM in a young patient induced us to approach these lesions. We presented a case of a large basal ganglia AVM totally removed by a three-staged operation. A 26-year-old man who had twice experienced intracranial hemorrhage was admitted for examination. On admission, mild left hemiparesis, hypesthesia and left hemianopsia were disclosed. CT scan showed the AVM was located in the posterior thalamus with the hematoma cavity laterally. Right carotid and vertebral angiograms demonstrated a large AVM, 5cm in diameter, supplied by the anterior choroidal artery (AchoA), the lateral lenticulostriate arteries (I-LSAs), the lateral posterior choroidal artery (LPchoA) and the thalamo-perforating artery. Drainage was via the internal cerebral vein and the basal vein of Rosenthal. MRI demonstrated more clearly the anatomical relationship of the nidus and surrounding structures. The patient underwent a three staged operation. At the first operation AchoA was interrupted in the inferior horn of the lateral ventricle (IHL) via the hematoma cavity using the trans-sylvian approach. The anterior part of the nidus was dissected with all except one of the I-LSAs being disconnected. At the next operation by occipital interhemispheric approach, some feeders from the posterior cerebral artery were coagulated and disconnected. The medial and posterior part of the nidus was dissected from the thalamus along with the choroid plexus of the trigone of the lateral ventricle.(ABSTRACT TRUNCATED AT 250 WORDS)