The Effect of beta-Thalassemia Minor on the Optic Nerve Head Analysis.

Background: A variety of ophthalmologic findings have been reported in patients with anemia.

Aim: To determine the effect of beta-thalassemia minor on the optic nerve head topographic analysis.

Methods: A total of 39 beta-thalassemia minor patients were divided into 2 groups. Patients with iron, folic acid, or vitamin B12 deficiency were ruled out. Group 1 comprised 20 patients with anemia, and group 2 comprised 19 patients without anemia. One eye of each patient was included into the study. All subjects underwent complete ocular examination. Optic nerve head topographic analysis was performed by using a confocal scanning laser ophthalmoscope type Heidelberg retina tomograph (HRT). The following stereometric parameters were evaluated: disc area, area and volume of cup, area and volume of neuroretinal rim, measure of cup shape, and mean retinal nerve fiber layer thickness.

Results: The mean age of group 1 and 2 were 26.8±7.6 and 25.6±4.5 years, respectively (P=0.91). Their mean disc areas were 2.01±0.3 mm² and 2.53±0.6 mm², respectively (P =0.009). The differences between groups for area and volume of cup, area and volume of neuroretinal rim, cup shape measure, and mean retinal nerve fiber layer thickness were insignificant (p>0.05). There was no significant difference between mean intraocular pressure of both groups (p=0.93).

Conclusion: In beta-thalassemia minor, patients with anemia, optic disc area showed a statistically significant reduction compared to the patients without anemia. Further clinical trials on ocular blood flow and optic nerve oxygenation changes may highlight the role anemia in the optic nerve head of the beta-thalassemia minor patients.