Investigation of the color discrimination ability using the Farnsworth-Munsell 100-hue test and structural changes by SS-OCT in patients with transfusion-dependent beta-thalassemia

• Published in: Photodiagnosis and photodynamic therapy Vol. 43; p. 103716
• Main Authors: Koctekin, Belkis, Dogan, Berna, Erdem, Ramazan, Buber, Hakan, Kurtoglu, Erdal, Karakus, Volkan
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.09.2023
• Subjects: Beta-thalassemia; blood transfusion; color discrimination; Farnsworth Munsell 100-hue test; swept-source optical coherence tomography; swept-source optical coherence tomography; blood transfusion; Beta-thalassemia; Farnsworth Munsell 100-hue test; color discrimination; Color discrimination; Farnsworth Munsell 100-hue test, Swept-source optical coherence tomography; Blood transfusion
• ISSN: 1572-1000; 1873-1597
• DOI: 10.1016/j.pdpdt.2023.103716

•Color discrimination ability was found less in patients with TDβ-T than controls.•Color discrimination in the b-y color zone was less than r-g zone in the patients.•Color vision of the patients using chelators was not affected by hemoglobin ≤9.5 g/dL and ferritin≥1000 μg/L levels.•Choroidal thickness measured on SS-OCT was found to be reduced in patients with TDβ-T.•SS-OCT can provide information about retinal changes of the patients with TDβ-T. This study aimed to examine the color discrimination ability of patients with transfusion-dependent beta-thalassemia (TDβ-T) in detail using the Farnsworth Munsell (FM) 100-hue test and to evaluate structural changes by swept source-optical coherence tomography (SS-OCT). This prospective, sectional study included 40 patients (79 eyes) with TDβ-T and 21 controls (42 eyes). The volunteers underwent a detailed ophthalmological examination and swept-source optical coherence tomography imaging. Excluded were those with congenital color vision defects detected with the Ishihara pseudoisochromatic test. The patients’ color vision was examined using the FM 100-hue test. The total error score (TES), the blue-yellow local error score (b-y LES), and the red-green local error score (r-g LES) were calculated. OCT findings were detected by SS-OCT (DRI-OCT, Triton). p <0.05 was considered significant. The mean age was 30.34±6.94 years in the patient group and 32.26±6.43 years in the control group (p=0.078). The patient group had a significantly lower hemoglobin level (9.25±0.87 g/dL vs. 14±1.79 g/dL, p<0.001) and a significantly higher ferritin level (2665.56±2658.05 μg/L vs. 52.87±69.59 μg/L, p<0.001) compared to the control group. The mean TES, b-y LES, and r-g LES were higher in the patients than in the controls (64.84±30.18 vs. 28.45±16.55, p<0.001, 34.21±17.54 vs. 15.67±10.07, p<0.001, and 29.32±15.72 vs. 12.12±7.94, p<0.001, respectively). The patients had a higher b-y LES than r-g LES (34.21±17.54 vs. 29.32±15.72, p=0.015). Choroidal thickness was lower in the patients than in the controls (284.34±63.55 µm vs. 324.98±88.05 µm, p=0.043). We found that the color discrimination ability of the patients with TDβ-T was reduced in both the r-g and b-y color axes compared to the controls, and their color discrimination ability in the b-y color axis was more affected than in the r-g axis.