Evaluation of ocular defects and its relevant factors in patients with beta thalassemia major in Sari Boo Ali Sina hospital, (2006-2008)

Background: As There is not accurate information about ocular defects in Thalassemia Major (TM) patients in Mazandaran province ,this study was designed to assess the prevalence of ophtalmopathies in thalassemic patients and also recognize its relevant factors in Sari Boo Ali Sina hospital. Sari. Materials and Methods: This descriptive Cross-sectional was Carried out on 60 TM patients in Thalassemia center at Sari Boo Ali Sina hospital. Subjects were selected by systematic sampling. After gathering demographic data , patients were evaluated about their illness and its complications from their medical records. Their visual acuity was assessed using Snell chart by an optometrist. Evaluation of retina was done by our ophthalmologist colleague. Visual evoked potential (VEP) was assessed by TOENEES instrument made in Italy which had the ability to assess both VEP and P300 . Findings were analyzed by SPSS13 software and Chi square and Mann-whitney tests. Results: 60 patients underwen this study that 33 of them (55%) were male. 4 of them (6.6%) had problems in visual acuity . 3 of these became normal after refractive correction. 3 patients (5%) had Inferior Posterior Cortical Cataract. 2 of them (3.3%) had punctuate lens cortical opacity and one (1.7%) had mild nuclear sclerosis. 4 patients( 6.7%) had macular pigmentation and one (1.7%) had left optic nerve head pit. No abnormal finding was detected in VEP, such as latency in voltage. Conclusion: Totally 20 patients had ocular complications. These defects can be a result of desferal toxicity or Iron toxicity and drug effects on binding to cupper and zinc and removing them from retinal cells or extramedulary hematopoesis. So based on the results, ophthalmologic evaluation of TM patients and tight desferal dose adjustment in these patients seems necessary.