P.125 Cerebral AVM recurrence post gamma knife obliteration: a 20 year single centre retrospective analysis and review of literature

Abstract

Background: Pediatric arteriovenous malformations (AVMs) are rare, but represent the leading cause of intracranial hemorrhage in children. These are traditionally understood to be congenital lesions, however AVMs recurrence within previously unaffected tissue challenges this understanding. Recurrence after microsurgery and endovascular treatment have been studied in greater detail, but little literature exists surrounding recurrence after Gamma Knife Radiosurgery (GKRS). Methods: We performed a retrospective chart review of all pediatric AVMs treated with GKRS at our centre. Charts were assessed by two reviewers to identify cases of AVM recurrence after angiographically confirmed obliteration. To contextualize our institutional patterns, we also performed a structured literature review of published data reporting pediatric AVM recurrence after GKRS. Results: Our institutional review revealed two cases of AVM recurrence after angiographically proven cure, and our review of literature identified nine retrospective reviews and three case reports, which in total reported 22 individual cases of recurrence. The recurrence rate in the retrospective reviews ranged from 0 to 18%. Conclusions: The current work illustrates that while AVM recurrence is rare, it is a possible complication of GKRS. There was also a qualitative suggestion that embolization prior to CT increased risk of recurrence. Both these facts should be included in decision-making and patient counselling.