Retinal nerve fiber layer thickness in children with β-thalassemia major

Abstract

Background β-thalassemia major, a disease of defective globin β-chain synthesis, is characterized by anemia caused by a combination of hemolysis, ineffective erythropoiesis, and iron overload. Children with β-thalassemia major are liable to impairments in the retinal microvasculature. The progressive retinal and retinal pigment epithelium pathologies caused by deferoxamine may lead to visual loss.Purpose The aim of this study was to measure the retinal nerve fiber layer (RNFL) thickness in children with β-thalassemia major and to compare it with a healthy control group.Patients and methods This is a cross-sectional study that included 15 patients with β-thalassemia major and 15 healthy children as a control group, who were recruited from the Pediatric Department, Menoufia University Hospital, Shebin El Kom, Menoufia, Egypt, from March 2020 to December 2020. All children were subjected to a standard ophthalmological examination. The RNFL thickness measurements were performed by Spectralis Heidelberg optical coherence tomography.Results The mean hemoglobin level was statistically significantly less in the β-thalassemia major group (6.79±0.69 g/dl) compared with the control group (13.67±0.57 g/dl) (P<0.001). The serum ferritin level was significantly increased among the β-thalassemia major group (4280.0±1250.83 ng/ml) compared with the control group (60.70±92.46 ng/ml) (P<0.001). The mean blood transfusion history among patients with β-thalassemia was 1.07±3.37/month. The nasal superior, nasal inferior, and nasal sectors were significantly thinner in patients with β-thalassemia major than in the control group (P<0.05). In patients with β-thalassemia major, the average RNFL thickness and each individual quadrant RNFL thickness (temporal, temporal inferior, and nasal inferior) were not statistically significantly correlated with serum ferritin and serum hemoglobin (P>0.05). On the contrary, the nasal superior sector was significantly correlated with serum hemoglobin, whereas the temporal superior and nasal sectors were significantly correlated with serum ferritin (P<0.05).Conclusions The RNFL was thinner in patients with β-thalassemia major compared with the control group. The RNFL thickness was positively correlated with the decreasing hemoglobin level.