Introduction: Cerebellar arteriovenous malformations (AVMs) represent one of the most challenging brain lesions to treat. They have been associated with a greater propensity for rupture and higher rates of morbidity and mortality than other brain AVMs (BAVMs). This investigation seeks to describe and characterize the features of these rare and unique lesions.
Methods: Retrospective review of cerebellar AVMs treated at two tertiary medical centers was performed. Patients surgically treated at Institution 1 from September 1999 to February 2013 and at Institution 2, from October 2008 to October 2015, were included. Neurological status was assessed using the modified Rankin Scale (mRS) score and post-operative angiography was used to confirm AVM obliteration.
Results: A total of 120 patients were treated; 70.8% (85/120) initially presented with hemorrhage and 37.5% (45/120) had hemorrhage requiring emergent surgery. Complete AVM obliteration was achieved in 89.9% (107/119) of patients; 63.3% (76/120) had good neurological outcomes (mRS <3); perioperative mortality was 5.8% (7/120) and 7.5% (9/120) for long-term mortality. Mean follow-up time was 1.82 years.
On average, patients with large AVMs (= 3cm) (p-value=<0.001), who received embolization prior to surgery (p-value=0.04), did not have associated aneurysm(s) present (p-value=<0.001), had an eloquent cerebellar AVM (p-value=0.03), or had a residual AVM after surgery (p-value=0.008) were significantly younger. Female patients exhibited a lower rate of AVMs with deep venous drainage (54.3% vs. 72.3%, p-value=0.049), decreased mortality (1.4% vs. 16.7%, p-value=0.003), and were less likely to experience ‘worsening’ in neurological status following treatment (p-value=0.003).
Conclusions: Cerebellar AVMs are rare lesions that exhibit unique disease characteristics. They have high rates of hemorrhage and mortality, and exhibit different characteristics between younger and older patients and between genders.
Patient Care: Hopefully by gaining a better understanding for the outcomes, technical success, and unique features of these lesions, this can allow for improved judgement and clinical decision making for treatment strategies.
Learning Objectives: By the conclusion of this session, participants should be able to 1) better understand the risk associated with surgical treatment along with the rate of technical success 2) and gain a better understanding for the features associated with these rare lesions.