Macular microvascular changes in children with transfusion-dependent beta-thalassemia

• Published in: Graefe's archive for clinical and experimental ophthalmology Vol. 259; no. 11; pp. 3283 - 3293
• Main Authors: AttaAllah, Heba Radi, Mousa, Suzan Omar, Omar, Ismail Ahmed Nagib
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.11.2021; Springer Nature B.V
• Subjects: Angiography; beta-Thalassemia - complications; beta-Thalassemia - diagnosis; Blood diseases; Case-Control Studies; Chelating agents; Child; Children; DNA nucleotidylexotransferase; Ferritin; Fluorescein Angiography; Fovea Centralis; Humans; Iron; Medicine; Medicine & Public Health; Microvasculature; Ophthalmology; Perfusion; Registration; Retina; Retinal Disorders; Retinal Vessels - diagnostic imaging; Thalassemia; Tomography, Optical Coherence; Vessels density; Transfusion-dependent thalassemia; Optical coherence tomography angiography; OCTA; Macular microvascular changes; Macular perfusion; FAZ
• ISSN: 0721-832X; 1435-702X
• DOI: 10.1007/s00417-021-05275-0

Background To investigate the effect of iron overload on macular perfusion among transfusion-dependent thalassemia (TDT) patients using optical coherence tomography angiography (OCTA) Methods The study is a prospective observational case–control study. It included 27 eyes from 27 children with transfusion-dependent β-thalassemia and 25 eyes from 25 age-matched controls. All participants were evaluated clinically and with OCTA Avanti RTVue-XR system (Optovue) to assess macular microvascular changes, by measuring vessels density (VDs) and foveal avascular zone (FAZ) area, at both superficial and deep retinal plexuses and at choriocapillaris level. Results Foveal and parafoveal zones were significantly thinner among thalassemia patients, with significantly larger FAZ area at the level of both superficial and deep retinal plexuses when compared with control group. The thalassemia group showed significant lower values compared with the controls regarding whole-image, foveal, and parafoveal deep VD. There were significant negative correlations between serum ferritin and deep (whole image and parafoveal) VD (r =  − 0.429, P = 0.026, and r =  − 0.452, P = 0.018, respectively). Choriocapillaris VDs (whole image and foveal) showed significant negative correlations with serum ferritin levels (r =  − 0.390, P = 0.044 and r =  − 0.401, P = 0.038, respectively) Conclusions Macular microvascular changes were detected by OCTA examination in patients with TDT, mostly due to iron overload effect, as we selected patients on iron-chelating agent with the least harmful effect on the retina. The most affected layer is the DCP. Changes at the deep layer could be used as a sensitive biomarker for early macular perfusion changes in those patients. Trial registration Study registration number is UMIN000042657, date of registration: 2020/12/04 (retrospectively registered).