Evaluation of visual acuity and contrast sensitivity in early cataract

Abstract

Background and Objective: Age-related cataract is one of the most important causes of blindness. Early detection of cataracts can help alleviate the problems caused by this disease. This study was performed to evaluate the visual acuity and contrast sensitivity of patients with early cataract. Methods: This descriptive-analytical study was performed on 54 patients (108 eyes) in the age range of 35 to 50 years with early stage cataract referred to Alzahra Ophthalmology Hospital in Zahedan, souh-west of Iran. The ethnicity of all the participants was Baluchi and Sistani. After correcting the refractive errors if the inclusion criteria were met, visual acuity with E chart at 6 m and Pelli Robson contrast sensitivity chart at 3 m were measured as monocular. Results: There was a significant correlation between visual acuity and contrast sensitivity (P=0.033, r2=0.205). The mean of visual acuity and contrast sensitivity were not significantly different in the two Baluchi and Sistani ethnicities. But visual acuity and contrast sensitivity were significantly different in the two genders (P<0.05). Conclusion: Early cataract, although having a minor effect on visual acuity, can reduce contrast sensitivity. Therefore, measuring of contrast sensitivity in normal light condition in patients with early cataract who complain of blurred vision despite normal visual acuity can more accurately assess their visual function.

Keywords

• visual acuity
• contrast sensitivity
• cataract