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Updated: Oct 27, 2025

Assessing Early Stage Open-Angle Glaucoma in Patients by Isolated-Check Visual Evoked Potential
Published on: May 25, 2020
A Population-Based Cross-Sectional Study of Visual Impairment in West Godavari and Krishna Districts in Andhra
Srinivas Marmamula1,2,3,4, Vijay Kumar Yelagondula2, Rohit C Khanna1,3,4
1Allen Foster Community Eye Health Research Centre, Gullapalli Pratibha Rao International Centre for Advancement of Rural Eye Care, L V Prasad Eye Institute, Hyderabad, India.
Purpose:
To report the prevalence and causes of visual impairment (VI) among those aged ≥40 years in West Godavari and Krishna districts in Andhra Pradesh, India.
Methods:
Trained teams visited the households in the selected clusters and conducted eye examinations. Presenting visual acuity (PVA) was assessed for distance and near. Torchlight examination was conducted to assess the anterior segment. Non-mydriatic retinal images were also obtained. VI was defined as PVA worse than 6/18 in the better eye. It included Moderate VI (PVA worse than 6/18 to 6/60), Severe VI (PVA worse than 6/60 to 3/60) and Blindness (PVA worse than 3/60). Multiple logistic regression analysis was conducted to assess the risk factors for VI.
Results:
In total, 2587/3000 (86.2%) participants were examined. Of this, 1406 (54.4%) were women and 1224 (47.3%) had no education. The age- and gender-adjusted prevalence of VI was 12.8% (95% CI: 11.5-14.1). Compared to the 40-49-year age group, the odds of having VI among those aged 50-59 years, 60-69 years and ≥70 years were 2.93 (95% CI: 1.91-4.52), 6.53 (95% CI: 4.31-9.91) and 17.45 (95% CI: 11.50-26.46), respectively. Those respondents who had no education had a higher odds (OR: 1.73; 95% CI: 1.34-2.23) of VI compared to those who were educated. Cataract (62.4%) and uncorrected refractive errors (29.8%) were the leading causes of VI. Over 90% of the VI was due to avoidable causes.
Conclusion:
VI is a major public health challenge in Andhra Pradesh. Over 90% of this burden is avoidable and can be eliminated by low-cost interventions such as spectacles and cataract surgery.
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