Microsurgery of Spetzler-Martin Grades III, IV and V Arteriovenous Malformations

Abstract

Introduction: Brain arteriovenous malformations (AVMs) are congenital complex network of dysplastic vessels and represent challenging neurosurgical pathology. There are many controversies in the literature regarding which is the best treatment for Spetzler-Martin high grade AVMs. Therefore, the authors present their operative experience in thirty-three grade III, IV and V brain AVMs and underline the fundamental role of microsurgery in the treatment of these high-grade AVMs. Material and Method: We retrospectively reviewed medical records of patients with brain AVMs operated from 2009 to 2013 by the same senior neurosurgeon, in “Bagdasar-Arseni” Emergency Clinical Hospital. Results: Fifty patients with brain AVMs underwent surgery. Mean age was 37.58 years, varying from 17 to 73 years. Five patients (10%) had AVMs Spetzler-Martin grade I, 12 patients (24%) grade II, 21 patients (42%) grade III, 7 patients (14%) grade IV and 5 patients (10%) grade V. Forty-three patients (86%) had supratentorial and seven patients (14%) had infratentorial lesions. We included in our study thirty-three grade III, IV and V operated in the Fourth Department of Neurosurgery, Emergency Clinical Hospital Bagdasar-Arseni. The medium age of the patients was 33,6 years. There were 16 men and 17 women. Twenty-four (72,8%) patients presented with ruptured AVM, with various types of intracranial hemorrhage, like: intraparenchymatous hematoma, intraventricular hemorrhage and subarachnoid hemorrhage. There is worth to mention that all posterior fossa arteriovenous malformation presented with hemorrhage at admittance. The rest of the cases, nine cases (27,2%), presented with seizure. The preoperative neurological status of the patients presented with ruptured AVM were worse (medium modified Rankin Score 3,8) compared with patients with unruptured AVM (medium modified Rankin Score 1,6). We performed total resection of AVMs in 29 cases (87,8%). Four patients (12,2%) with arteriovenous malformation located in the eloquent areas of the brain had residual nidus. Patients with residual nidus were referred to stereotactic radiosurgery with good outcome. Twenty-one patients (63,6%) presented increased modified Rankin Score (mRS) following surgery, in 8 cases (24,3%) mRS remained unchanged and 3 patients (9,1%) presented decreased mRS. There was one case of death (3%), a 24 year-old female with a Spetzler-Martin grade V ruptured right temporo-parietal arteriovenous malformation, who presented in emergency with a giant right hemispheric intraparenchimatous hematoma. In that case, the Glasgow Coma Scale at admittance was 5 points and neurological exam revealed acute brainstem dysfunction. Long term follow-up (one year postoperative) showed complete recovery of neurological deficits in all patients with excellent quality of life in 22 patients (66,6%) and good quality of life in 10 cases (30,4%). The seizures remitted completed in 6 patients, while 3 patients required only minimum doses of antiepileptic drugs. The patients who presented with ruptured AVM required after operation only preventive anticonvulsivant therapy for maximum three months.