O-025 Technical options to obtain complete obliteration of vein of galen aneurysmal malformation

Background Since staged trans-arterial endovascular embolization (TAE) became the main strategy to treat vein of Galen aneurysmal malformation (VGAM), this otherwise lethal disease has become manageable. The antenatally diagnosed cases need proper planning for delivery and neonatal management. Symptomatic neonates with congestive heart failure (CHF) benefit from trans-umbilical TAE with closure of fistulas in order to reduce CHF and improve survival. In infants, symptomatic hydrocephalus or venous hypertension requires urgent TAE to facilitate normal brain development. Even in asymptomatic cases, staged TAE in a safe manner can be beneficial before development delay. Staged TAE of the choroidal feeding arteries has been reported to result in cure. However, some VGAMs remain technically challenging to obtain complete obliteration solely with this technique. If the choroidal feeders are not accessible after prior TAE, other options need to be sought. We reviewed the final few procedures in consecutively cured VGAM patients and assessed the techniques utilized to obtain total obliteration. Materials and Methods This is a retrospective chart and radiographic investigation of a consecutive series of 124 VGAM cases treated between 2004 and 2021 in our institution. Obvious arteriovenous malformation with aneurysmal dilatation of vein of Galen was not included. The strategy in this period was to repeat TAE of the choroidal feeders until the VGAM was totally occluded or until choroidal feeder access was no longer safe. In 81 out of 124 patients, the VGAM was totally or near totally (>95%) obliterated. There were 7 death because of the SHF instead of aggressive TAE or because of the hemorrhagic complication. 36 patients are currently undergoing staged embolization and total obliteration hasn’t been achieved and are therefore excluded from this study. Results Among the 81 cases, 66 cases (81%) achieved total to near total obliteration of the VGAM solely with staged TAE through choroidal artery or thalamoperforating artery feeders. Most of them were found to have total occlusion in the 3 to 6 month follow up angiogram after a final TAE, even when the malformation had been present at the final angiogram in the last TAE. In 4 cases (5%), the dural supply of the malformation was embolized with ONYX from the external carotid artery as the final procedure; and total obliteration was achieved. Transvenous embolization at the last procedure led to complete occlusion of the VGAM in 9 patients (11%). Two cases were referred to stereotactic radiosurgery (SRS) after the age of 10 and total obliteration of the residual malformation was confirmed in the 2 year follow up cerebral angiogram post SRS. There was one hemorrhagic complication occurring in a case after final TVE. Conclusions Staged transarterial n-BCA embolization of the choroidal arteries effected cure of VGAM with a good outcome in more than 80% of the 124 cases. If the access is challenging, multimodal approach with transdural ONYX embolization, transvenous embolization or even SRS can be considered. Further assessment of natural history of patients with near occlusion is warranted. Disclosures T. Shigematsu: None. J. Fifi: None. A. Berenstein: None.