J Korean Ophthalmol Soc.  2009 May;50(5):670-676. 10.3341/jkos.2009.50.5.670.

The Relationship Between Asphericity and Visual Acuity After Wearing Reverse-Geometry Lens

• Na JH
• Choi JH
• Yang JW
• Lee YC
• Kim SY

• KMID: 2212296
• DOI: http://doi.org/10.3341/jkos.2009.50.5.670

Abstract

PURPOSE:To report the change of corneal asphericity and the relationship between asphericity and visual acuity after wearing the reverse-geometry lens.
METHODS
The authors reviewed out-patient records of 37 consecutive patients wearing reverse-geometry lenses. The patients were followed up from July 2004 to December 2007. The unaided visual acuity (VA), spherical equivalent (SE) and asphericity before and after wearing the lens were compared. The relationship of SE and final VA, initial astigmatism and final VA, and asphericity and final VA was also analyzed. In addition, the relationship between the increment of VA and asphericity was determined.
RESULTS
VA and SE improved and the asphericity decreased after wearing the lens (p<0.05). There was high correlation between the spherical equivalent and final visual acuity (p<0.001), and no correlation between asphericity and final visual acuity (p=0.358) was observed. However, the lower the initial asphericity, the greater the increment of visual acuity observed (p=0.048).
CONCLUSIONS
Initial corneal asphericity can be a predictor of increment of VA after wearing reverse-geometry lenses.

Keyword

Corneal asphericity; Corneal eccentricity; Orthokeratology; Reverse-geometric lens; Spherical equivalent

MeSH Terms

Astigmatism
Humans
Outpatients
Visual Acuity

Figure

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  Figure 1. The relationship of the initial SE and the final VA. This graph shows that the eyes are more myopic, the visual acuity is worse.

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  Figure 2. The relationship of the final SE and the final VA. This graph closely resembles the figure 1. Similarly the myopia is more severe, the visual acuity is worse.

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  Figure 3. The relationship of the initial astigmatism and the final VA. This graph illustrates that the astigmatism is higher, the final visual acuity tends to be lower.

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  Figure 4. The relationship of the initial asphericity and the final VA. Initial asphericity did not affect the final visual acuity.

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  Figure 5. The relationship of the final asphericity and the final VA. The final asphericity did not have an effect on final visual acuity.

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  Figure 6. The relationship of the initial asphericity and the increment of VA. As the initial asphericity was lower, the increment of visual acuity was higher.

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  Figure 7. The relationship of the final asphericity and the increment of VA. The lower the final asphericity, the higher the increment of visual acuity.

Reference

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