Influence of Age on the Visual Fields of Normal Subjects: A Clinical Study

Background: Age-related eye diseases are becoming the leading cause of visual impairment, which causes tremendous impact on their mental and social health and affects the overall quality of life. Precise quantification of the relationship between age and the visual function would enable a correct estimate of the level of visual performance expected in a normal subject of a specific age. Aim: This study aims to examine the rate of decline in retinal sensitivity with respect to ageing using visual field to determine the pattern of decline in relation to age. Method: A sample of 72 subjects aged between 15 and 74 years were divided into four incremental age-groups with each group having a maximum age variation of 15 years. Visual fields of all the subjects were assessed using Humphrey Field Analyzer Model-720 devised by Allergan Medical Corporation, California. The test strategy adopted was Swedish Interactive Threshold Algorithm and 30-2 program. P value was calculated using t-test for equality of means using a significant two-tailed test. Linear regression analysis with Analysis of Variance was applied to determine the pattern of relationship between age and point-wise retinal sensitivity. Results: The results show an average loss of sensitivity of 0.7 dB/ decade up to 60 years of age and profound loss of 1.8 dB/decade after 60 years of age. The decline was greater in the superior field. The pattern of decline was found to be linearly correlated up to 60 years(r = -0.656, R = 42%). The decline has been found to be statistically significant (P = 0.001). Conclusion: The study revealed a gradual decline in the retinal sensitivity as the age advances, with a slow decline up to the age of 60 years and an accelerated loss after 60 years. The decline was more marked in males after the age of 60 years.