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Corneal asphericity and spherical aberration after refractive surgery
Katia M Bottos1, Mauro T Leite, Marichelle Aventura-Isidro
1Shiley Eye Center, University of California San Diego, La Jolla, California, USA.
Journal of Cataract and Refractive Surgery
|May 21, 2011
Summary
Refractive surgery alters corneal asphericity (Q) and spherical aberrations. Myopic corrections tend to increase Q and aberrations, while hyperopic corrections decrease them, depending on the refractive error magnitude.
Area of Science:
- Ophthalmology
- Corneal Surgery
- Wavefront Aberrometry
Background:
- Corneal asphericity (Q) and spherical aberrations influence visual quality.
- Understanding post-refractive surgery changes is crucial for predicting visual outcomes.
Purpose of the Study:
- To evaluate changes in corneal asphericity (Q) and spherical aberrations after refractive surgery.
- To assess the impact of myopic and hyperopic corrections on corneal optics.
Main Methods:
- Cohort study evaluating patients after wavefront-guided laser in situ keratomileusis (LASIK).
- Scheimpflug imaging used to measure Q values and corneal spherical aberrations preoperatively and postoperatively.
- Analysis included 177 myopic and 32 hyperopic eyes.
Main Results:
- Myopic corrections resulted in more positive Q values and spherical aberrations.
- Hyperopic corrections led to more negative Q values and spherical aberrations.
- Changes in Q and aberrations were correlated with the magnitude of preoperative refractive error.
Conclusions:
- Refractive surgery induces opposing directional changes in corneal asphericity and spherical aberrations for myopic and hyperopic corrections.
- The extent of these optical changes is dependent on the degree of refractive correction applied.
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