Imaging characteristics and endovascular treatment strategy for cerebellar arteriovenous malformations

Cerebellar arteriovenous malformations (CAVMs) have increased probabilities of rupture and bleeding compared with arteriovenous malformations (AVMs) in other locations of the brain. Endovascular treatment (EVT) for CAVMs is difficult; as the angioarchitecture of CAVMs is complex, EVT may be associated with complications, due to the involvement of crucial structures, such as the brainstem. The present study aimed to determine the efficacy of EVT for CAVMS. For this purpose, 33 cases of CAVMs treated with EVT from January, 2015 to January, 2020 were retrospectively analyzed. The 33 patients were aged 8 to 73 years (mean age, 40.4±17.8 years) and 21 were female (63%, 21/33). Rupture and bleeding occurred in 29 patients (87.9%, 29/33). Among the 33 CAVM cases, 15 (45.5%, 15/33) were fed by a single artery, and 18 (54.5%, 18/33) were fed by multiple arteries. In total, 27 patients (81.8%, 27/33) had superficial vein drainage alone. Among the 33 cases, 15 were complicated by 16 aneurysms, including 14 prenidal aneurysms and 2 intranidal aneurysms. Among the 33 cases, the nidus of the CAVM (87.9%, 29/33) was treated with Onyx(™) casting in 29 patients: 8 cases (27.6%, 8/29) had an embolization volume of <1/3 of the nidus, 11 cases had a volume of 1/3-2/3 of the nidus (37.9%, 11/29) and 10 cases had a volume >2/3 of the nidus (34.5%, 10/29). Among the EVT complications, there were 3 cases (9.1%, 3/33) of intraoperative and post-operative bleeding, which resulted in two deaths (on the 1st and 7th days). The length of hospital stay was 10.7±5.4 days. In total, 27 patients (81.7%, 27/33) had a Glasgow Outcome Scale (GOS) score of 5 at discharge. On the whole, the present study demonstrates that overall, EVT is a feasible treatment for CAVM and may be used to obtain acceptable therapeutic effects.