Clinical and radiological outcome after microsurgical management of ruptured and unruptured brain arteriovenous malformations.

The treatment of unruptured & ruptured AVMs remains controversial. Microsurgical resection of the AVM offers the higher cure rate, but the associated morbidity and mortality may exceed that of the AVM's natural history. Single center retrospective cohort study of 120 consecutive patients harboring intracranial AVM operated on between January 2010 and June 2023. The AVM was ruptured in 68% of cases (mean hematoma volume 24,5 cc / median 16,5). Preoperatively, 39% of the patients presented with massive intracranial hemorrhage leading to elevated intracranial pressure, 24% with epilepsy and 31% with a motor paresis.. The initial Glasgow Coma Scale was less than 12 in 36% of cases in the ruptured AVM group. The AVM location was lobar in 81% of cases. The Spetzler-Martin grades were 1, 2, 3 and 4 in 26%, 41%, 15% and 1% of cases, respectively. Seventeen patients (14%) harbored an infratentorial AVM. The mean nidus diameter was 17 mm (range 5-55 / median 13 mm). All patients underwent surgical resection of the AVM. An external ventricular drainage was necessary in 25% of cases. Thirteen patients (11%) had received preoperative embolization. The occlusion rate was 89%. A nidus residue was shown on postoperative angiography in 13 patients (11%). Of those, 6 patients underwent a 2nd stage surgical treatment while 2 other (15%) had received a salvage embolization, with a 100% complete obliteration rate. The obliteration rate at discharge was 96%. Five patients harboring a residue were allocated to a Wait& Scan strategy. The Glasgow outcome scale was 5 in 68%, 4 in 14%, 3 in 8%, 2 in 7% of cases. Three patients (3%) died of ruptured AVM despite surgery. Low grade cranial AVMs can be safely managed surgically, with a high cure rate and satisfying outcome. The surgical resection of ruptured AVMs is significantly more challenging and associated with inferior obliteration rate and postoperative outcome.