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Updated: Jun 17, 2026
05:46
Correction of Presbyopia by Monocular Bi-Aspheric Ablation Profile
Published on: September 20, 2024
[Contrast sensitivity and higher order aberration after conventional LASIK treatment]
V Loukotová1, E Vlková, M Horácková
1Ocní klinika LF MU, FN Brno. vera_loukotova@yahoo.com
Summary
Conventional LASIK treatment can decrease mesopic contrast sensitivity and increase higher-order aberrations, particularly spherical aberrations. While some correlations exist post-surgery, a significant link between aberrations and contrast sensitivity was not proven.
Area of Science:
- Ophthalmology
- Refractive Surgery
- Corneal Aberrometry
Context:
- Conventional LASIK (Laser-Assisted In Situ Keratomileusis) is a common refractive surgery procedure.
- Understanding post-operative visual quality, including contrast sensitivity and aberrations, is crucial for patient outcomes.
- Mesopic conditions present unique challenges for visual function after refractive surgery.
Purpose:
- To evaluate photopic high-contrast visual acuity, mesopic contrast sensitivity, and higher-order aberrations after LASIK.
- To compare the changes and post-operative development of these visual parameters.
- To analyze the relationship between aberrations and contrast sensitivity following LASIK.
Summary:
- One year post-LASIK, visual acuity improved, but mesopic contrast sensitivity decreased at 12 c/deg.
- Conventional LASIK significantly induced higher-order aberrations (HOA) and spherical aberrations (SA).
- HOA increase correlated with the degree of correction, while SA increase was independent of initial refractive error. No significant correlation was found between HOA/SA and contrast sensitivity at 12 months.
Impact:
- LASIK can alter visual function, necessitating careful patient selection and counseling regarding potential changes in contrast sensitivity.
- The induction of aberrations, particularly spherical aberrations, is a notable consequence of conventional LASIK.
- Further research may explore newer LASIK technologies or nomograms to mitigate these visual disturbances.
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