Uncorrected visual acuity in patients with simple myopic astigmatism based on the power and axis of the astigmatism Original research study
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Abstract
Purpose: The aim of the current study is to assess uncorrected visual acuity in eyes with simple myopic astigmatism.
Methods: patients with simple myopic astigmatism who had no history of surgery or pathology with best-corrected visual acuity of logMAR 0.0 (or 6/6) were included in this study. In the present study, eyes were classified into three groups; with-the-rule (WTR) (180 ±30), against-the-rule (ATR) (90 ±30) and oblique. The comparison of uncorrected visual acuity among these three groups was made based on the power and type of refractive and corneal astigmatism.
Results: Only right eye per participant was chosen, providing a final sample of 1435 eyes. The number (percentage) of eyes with WTR, ATR and oblique astigmatism were 555 (38.7%), 681 (47.5%) and 199 (13.9%) respectively. The mean uncorrected visual acuity was different among three groups (p <0.001). Mean logMAR visual acuity in eyes with 1 D of astigmatism or less were 0.06 (±0.09), 0.07 (±0.09) and 0.06 (±0.08) in WTR, ATR and oblique astigmatism respectively. Mean logMAR visual acuity in eyes with greater than 3 D of astigmatism were 0.51 (±0.12), 0.17 (±0.06) and 0.43 (±0.19) in WTR, ATR and oblique astigmatism respectively which showed a significant difference among them (p <0.001).
Conclusion: The magnitude and axis of astigmatism both were associated with uncorrected visual acuity in eyes with simple myopic astigmatism so that increasing the power of astigmatism reduces vision.
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Address reprint requests to: Medical Education, Marcin Kuźma (marcin.kuzma@mededu.pl)
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