Maryam Muhammad Nadeem, Ayesha Mansoor, Malaika Younus, Rabia Bushra Ehsan, Fariah Ata, Fareena Tehreem


Background: Accommodative convergence to accommodation (AC/A) ratio expresses the quantitative relationship between the convergence and accommodation. Purpose of this study was to assess and compare the effect of red and green filters on high and low AC/A ratio in emmetropes.

Materials & Methods: A comparative cross-sectional study was conducted in The University of Faisalabad. Total one hundred (100) emmetropic females from 18 to 25 years of age (20 having low AC/A ratio and 80 with high AC/A ratio) were included in the study through purposive sampling technique after obtaining informed verbal and written consent. Data was collected using self-designed examination based proforma. AC/A ratio was measured with heterophoric method initially without any filters, and then with red and green filters. Data was analyzed using SPSS version 22. Paired t-test was applied to assess the effect of red and green filters on the base line and then independent t-test was applied to compare the effect of red and green filters.

Results: Total 100 emmetropic females revealed that red and green filters have decreased high AC/A ratio and improved low AC/A ratio (p <0.001). Moreover, it was observed that red filters have improved low AC/A ratio (p-0.023) and decreased high AC/A ratio more effectively as compared to the green filters (p <0.05).

Conclusion: This study concluded that the red and green filters improved AC/A ratio and thus, can aid in preventing binocular visual anomalies effectively.


Asthenopia; Convergence excess; Eye protective devices; Lens accommodation; Myopia; Phorias.

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DOI: https://doi.org/10.46903/gjms/21.04.1369


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