[Surgical treatment of giant cerebral arteriovenous malformations]

Despite advances in the surgical management of cerebral arteriovenous malformations (AVMs), giant (AVMs (greater than 5 cm] are still considered unsuitable for direct surgical resection by most neurosurgeons. Some of the lesions are being treated with embolization, or embolization followed by surgical excision. Embolization alone is not curative and carries potential risks of neurological deficit as well involves multiple procedures. Fourteen patients with giant AVMs underwent surgical resection without prior embolization. Four of the AVMs were located primarily in the frontal lobe, two in the temporal lobe, one each in the parietal and occipital lobes, while six AVMs were localized to two lobes (temporal-occipital or parietal-occipital). Four patients had associated aneurysms with the arteriovenous malformation. Eight patients presented primarily with seizures. One of these had multiple subarachnoid hemorrhages while another had symptoms suggestive of transient vertebrobasilar ischemia. Two patients had one or more subarachnoid hemorrhages. The primary complaint in the remaining four patients was headache with other associated symptoms. The patients with AVMs involving the optic radiation have had varying degrees of visual field deficit not interfering with their function. There were no deaths and only three patients had deterioration of neurological function. One of these three had an intra cerebral hemorrhage secondary to an associated aneurysm rupture. We feel that the majority of these giant AVMs are amenable to direct surgical excision. It is difficult to asses, from the literature, the benefit of embolization prior to surgical excision in cases of giant AVMs. At least in one report dealing with combined treatment of seven giant AVMs, some authors stressed that preoperative embolization did not significantly alter the blood flow and, hence, potential of bleeding at the time of operation. Blood loss has not been a significant problem in our experience. When there is an associated aneurysm, it should be treated prior to or at the time of excision of the malformation.