Unruptured intracranial aneurysms in pediatric sickle cell disease: clinical and MR imaging follow-up of 296 patients.

Objective: Currently available data regarding unruptured intracranial aneurysms (UIAs) in sickle cell disease (SCD) are largely based on adult patients; this has made it challenging to reach a consensus on treatment decisions and follow-up strategies for pediatric SCD patients with UIAs.

Methods: A retrospective review of 296 SCD patients (aged 18 years or younger) who underwent MRA from January 2008 to September 2022 was performed. The vessel of origin and characteristics of the UIAs, including maximum diameter, laterality, and number, were evaluated. Demographic data, as well as history of vaso-occlusive crisis and moyamoya syndrome, were recorded. Interval change in size or morphology, as well as a new aneurysm development, were reviewed on follow-up MRA.

Results: Forty-nine aneurysms were identified in 32/296 (10.81%) patients, and they all had saccular morphology. In total, 30/49 (61.22%) aneurysms were in the anterior circulation. The ophthalmic segment of the internal carotid artery and the posterior cerebral artery were the most common locations (n = 12 [24.49%] each). Multiple aneurysms were seen in 11/32 patients (34.37%). Most of the African American patients had multiple aneurysms (n = 25/28 [89.3%]). Most aneurysms (n = 43 [87.75%]) were 3 mm or less in diameter. No significant difference in aneurysm size was noticed between aneurysms located in anterior or posterior circulation (p = 0.22). Similarly, age, sex, ethnicity, genotype, or aneurysm multiplicity were not associated with size. Follow-up MRA was available for 24/32 patients (75%). All except 2 aneurysms (n = 2/38 [5.3%]) were stable in size and morphology on follow-up. Interval progression in aneurysm size was noticed in 2 patients with multiple intracranial aneurysms (n = 2/11 [18.2%]).

Conclusions: In pediatric SCD patients, the incidence of UIAs was higher than previously reported. Those aneurysms demonstrated a tendency for multiplicity, an atypical anatomical distribution compared with that of adult brain aneurysms, bilateral involvement, and higher prevalence in African Americans. Although most of the aneurysms were stable, some showed interval growth in size.