Introduction and Purpose Flow diversion is a well-established endovascular therapy for treating intracranial aneurysms in adults. Although most pediatric intracranial aneurysms are effectively treated by deconstructive techniques, sometimes this is not feasible or safe. We aim to share our experience in treating complex intracranial aneurysms with flow-diverting stents.

Materials and Methods We conducted a retrospective analysis of consecutive patients aged 17 or younger who underwent treatment with flow diversion for intracranial aneurysms at a pediatric tertiary university center between March 2018 and May 2023. Demographic, clinical, and radiological characteristics at presentation and long-term follow-up were collected and analyzed. Pre-procedural and post-procedural antiplatelet medication administration was also documented. Safety was defined as ischemic/hemorrhagic events and mortality, while efficacy was measured by complete occlusion at final follow-up. Angiographic occlusion was assessed according to the O’Kelly-Marotta classification.

Results Five patients (4 females, 1 male) were included with a mean age at treatment of 11.2 years (range: 6–15). One patient had sickle cell disease and another had a suprasellar adenoma. One patient presented with subarachnoid hemorrhage, while one each presented with third nerve palsy, recurrent transient ischemic attacks and interval growth, and one was iatrogenic secondary to a neurosurgical procedure. Four patients failed balloon occlusion tests and no test was performed in one patient. Aneurysms were located in the internal carotid artery (n=3), middle cerebral artery (n=1), and posterior cerebral artery (n=1). Aneurysm types included saccular (n=2), traumatic/pseudoaneurysm (n=1), dissecting/dysplastic (n=1), and blister-like (n=1). All patients received weight-based dual antiplatelet premedication: aspirin and clopidogrel (n=2), aspirin and ticagrelor (n=1), and aspirin and eptifibatide (n=2); platelet testing was not available. A total of nine flow diverters were deployed, including Pipeline Flex (n=3), Pipeline Vantage (n=4), Silk Vista Baby (n=1), and Surpass Evolve (n=1). Optical coherence tomography was used in one case to acutely evaluate the stent apposition. Two patients underwent adjuvant coiling. One patient needed angioplasty after stent deployment. There were no immediate intraprocedural complications. Two patients developed symptomatic ischemic complications at 48 hours and 3 months post-treatment and one patient had an asymptomatic infarct on 24 hours post-procedure MRI. Dual antiplatelet medication was maintained for 6 months (n=3) and 12 months (n=2) based on imaging features and prior thrombotic events. The last follow-up imaging, including CT/MR Angiography and/or catheter angiography (mean: 17.6 months; range: 7–30) revealed complete occlusion of all aneurysms. One patient developed asymptomatic complete occlusion of the flow diverter construct with interval development of extensive pial collateralization 12 months after treatment.

Conclusion Initial short-term observations indicate that flow diversion is a feasible technique for well-selected pediatric intracranial aneurysms that cannot be effectively deconstructed. However, the risk of ischemic complications is significant, and extended monitoring is essential to better understand potential long-term risks and complications.

Disclosures C. Parra-Farinas: None. S. Chowdhury: None. V. Rea: None. S. Bickford: None. J. Quon: None. A. Kulkarni: None. V. Pereira: None. J. Spears: None. T. Marotta: None. L. Brandao: None. P. Dirks: None. P. Muthusami: None.