Microsurgical management of deep ruptured arteriovenous malformations of the basal ganglia and thalamus

Introduction: Deep AVMs are more difficult to operate compared with other supratentorial locations due to the long working corridor through the brain, location in eloquent areas and vicinity with brain critical structures. Material and Method: We report a series of 7 cases with deep AVMs operated in the Fourth Department of Neurosurgery, Emergency Clinical Hospital BagdasarArseni, between 2009 and 2013. Results: Six patients had ruptured AVMs and one presented frequent, refractory seizures due to a deep large porencephalic cyst. At admission, one patient presented mRS 2, 3 patients had mRS 4 and 3 patients had mRS 5. Patients underwent surgery and we achieved total resection in 5 patients and we left a residual nidus in two cases. These last 2 patients with residual nidus were referred to stereotactic radiosurgery Gamma Knife with good results. Following surgery mRS improved in all 7 patients, 3 had mRS 1, 3 had mRS 3 and one mRS 4. Outcome was favorable in 3 cases and slowly favorable in 4 patients. Conclusions: Deep AVMs frequently present sudden onset, with altered mental state, motor deficits and large intraparenchymatal hematomas. Surgery is mandatory for deep ruptured AVMs, being the only treatment that can provide neurological improvement through hematoma evacuation and cure through nidus resection. In experienced hands, deep AVMs can be successfully resected. Postoperative results are good, with improvement of state of consciousness and motor deficits. Adequate patient selection is essential in order to achieve a good postoperative outcome.