Determinants of macular thickness in normal Indian eyes

Abstract

Purpose: To generate normative data for optical coherence tomography (OCT) estimated macular thickness in Indian eyes and to establish its determinants. Materials and Methods: In this cross-sectional, observational, hospital-based study, 189 healthy Indian individuals underwent a fast macula OCT scan. Macular thickness was measured in nine ETDRS (Early Treatment Diabetic Retinopathy Study) regions, and the effect of gender, age, laterality, diabetes, and hypertension status on it was determined. Results: Females had a significantly thinner fovea (176.71 ± 23.32 μm v/s. 193.24 ± 20.95 μm) and inner macula (p < 0.001) as compared to males. With advancing age, foveal thickness increases (p = 0.012) while the superior and inferior outer macula thins (p = 0.018-0.027). Diabetes in the absence of any clinical retinopathy did not affect macular thickness. Hypertensive individuals had a thinner macula in all regions except the fovea and nasal macula. Conclusions: The thinner macula in females and age-related thinning should be considered when interpreting OCT scans of the macula. Diabetics with good visual acuity and no evidence of clinical retinopathy had normal macular thickness. Sub-clinical attenuation of vessels might account for the thinner macula in individuals with hypertension.

Keywords

• Age-related decline
• diabetic macula
• hypertensive maculopathy
• macular thickness
• optical coherence tomography