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Published on: March 29, 2022
Evaluating Asthenopia and Binocular Vision Parameters in Diamond Polishing Workers, The Mumbai Eye Disease Study
Maneck Nicholson1, Jeslin Jose1, Harshali Aldar1
1Shantilal Shanghvi Eye Institute, Mumbai, Maharshtra, India.
Purpose:
Investigate the prevalence of asthenopia and binocular vision abnormalities (BVA) among diamond polishers in Mumbai, India.
Methods:
The data was collected from eye screening in people working in one of the diamond industries in Mumbai, India. This retrospective cross-sectional study included only diamond polishers aged 18-35 with uncorrected 20/20 distance vision and N6 near vision. Others working in the diamond industry were excluded. Comprehensive eye screening included measuring Snellen acuity, refraction, and binocular vision tests. A CISS (Convergence Insufficiency Symptoms Survey) questionnaire was administered to assess binocular vision parameters and asthenopia.
Results:
In the screening cohort of 1,093 diamond industry screened workers, 66 people engaged in polishing were included in the study. The prevalence of BVA was 77.3%; stereo acuity abnormalities were the most common (63.6%), followed by accommodative insufficiency (43.9%). No significant association was found between CISS scores with age, work hours, or experience, although 10.6% of participants had CISS scores above 21. Age was significantly correlated with the near point of accommodation (P < 0.001), and older participants (26-35 years) exhibited higher fusional vergence abnormalities though not statistically significant.
Conclusion:
The high prevalence of binocular vision abnormalities among diamond polishers underscores the need for targeted interventions to reduce visual fatigue and improve working conditions in this high-demand occupation. Further studies are required to suggest corrective measures to enhance eye health and work productivity.
