T2* Magnetic Resonance Imaging Uncovers Hemosiderin Burden in Pediatric Hemophilia: A Call for Sensitive Imaging Biomarkers.

Hemophilic arthropathy remains the leading morbidity in hemophilia despite modern prophylaxis, and early joint damage may be missed by routine exams. This study explored T2* MRI as a noninvasive biomarker of hemosiderin deposition in pediatric hemophilia. Four children with severe hemophilia A or moderate-to-severe hemophilia B underwent T2* MRI after persistent joint symptoms. One patient demonstrated shortened T2* relaxation (9 ms) with structural joint pathology, while three showed higher values (22-26 ms) without pathology. Despite low bleeding rates and joint scores, T2* MRI identified occult damage, supporting its potential for early, personalized intervention in pediatric hemophilia populations globally.