ABSTRACT NUMBER: ESOC2026YS273 NEUROIMAGING OUTCOMES BEFORE AND AFTER HEMATOPOIETIC STEM CELL TRANSPLANTATION IN PATIENTS WITH SICKLE CELL DISEASE

Abstract Background and aims Sickle cell disease (SCD) is associated with a high burden of cerebrovascular complications detectable on brain MRI, including silent infarction and vasculopathy. Hematopoietic stem cell transplantation (HSCT) is a curative treatment for SCD, yet its effect on neuro-radiological abnormalities remains unclear. Methods We performed a matched pre– and post-HSCT MRI analysis in patients with SCD. Binary MRI variables were compared using McNemar’s test, and ordinal variables were analyzed with Wilcoxon signed-rank tests. Exact p-values were reported when appropriate. Evaluated MRI findings included cortical and subcortical infarcts, lacunes, moyamoya angiopathy, aneurysms, vasculopathy, cerebral atrophy, cerebral microbleeds (CMB), diffusion-weighted imaging lesions, and white matter disease severity. Results A total of 134 matched MRI pairs were analyzed. No statistically significant differences were observed in binary MRI findings following HSCT after correction using exact p-values. The prevalence of cortical infarcts increased modestly from 20.3% to 24.1% (exact p = 0.0625), while subcortical infarcts increased from 34.3% to 36.6% (exact p = 0.25). Minimal, non-significant changes were observed for lacunes, moyamoya angiopathy, atrophy, and CMB. The prevalence of aneurysms and vasculopathy remained unchanged. Ordinal analyses demonstrated no significant pre- to post-transplant differences in CMB number or size, lesion distribution, diffusion-weighted imaging abnormalities, or Fazekas scores for periventricular and deep white matter disease (all exact p > 0.05). In conclusion, HSCT in patients with SCD was associated with stability of MRI-detected cerebrovascular and structural brain abnormalities, suggesting a potential role in preventing progression of neuro-radiological disease. Conflict of interest Hussain BinAmir, nothing to disclose.