Management of ruptured posterior fossa arteriovenous malformations

Posterior fossa arteriovenous malformations (pAVMs) are rare and because of their location at or close to vital structures, their treatment remains challenging despite overall improvements in the management of cerebrovascular lesions. We reviewed our recent series of ruptured pfAVMs in search of guiding principles in the management of these complex lesions.

This is a retrospective series of consecutive patients admitted for a ruptured pfAVM from 2002 to 2013. We analyzed clinical and radiological data, as well as initial and definitive management. Outcome was assessed using the modified Rankin Scale (mRS) at 6 months.

The study included 34 patients (19 women and 15 men). Upon admission, 79% of patients presented with an intra-cerebellar hematoma, 42% of which required urgent drainage. Hydrocephaly was also present in 82% of patients, 56% of which required emergency ventriculostomy. There was an aneurysm associated with the AVM in 47% of cases. In 38% of the cases, the aneurysm was the source of the hemorrhage. Only 68% of patients were amenable to undergo treatment of the AVM: 24% exclusively by surgery, 9% by embolization, 3% by radiosurgery, and 32% using combined means. Five patients died within the first week: one as a direct result of the severity of the hemorrhage, and the other four due to re-bleeding before treatment. Outcome was favorable (mRS 0-2) in 71% of patients.

Patients with a ruptured pfAVM are often comatose upon admission, requiring emergency live-saving surgical treatment. An associated aneurysm is often the source of bleeding which if dealt with immediately, offers time to plan the most appropriate strategies to eliminate the AVM. Nevertheless, early re-bleeding is frequent, and a cause of concern as it often leads to death. Despite the gravity of the clinical condition upon admission, outcome is favorable for those amenable to treatment.