Theoretical analysis for spherical aberration induction with low-order correction in refractive surgery

Area of Science:

• Ophthalmology
• Optical Engineering
• Biomedical Engineering

Background:

• Ocular aberration correction is crucial for improving visual quality after refractive surgery.
• Understanding the induction of spherical aberration is key to optimizing surgical outcomes.
• Comparing different refractive surgical modalities is essential for clinical decision-making.

Purpose of the Study:

• To develop a theoretical framework for analyzing ocular aberration correction.
• To compare conventional and Q-preserved refractive surgical treatments regarding aberration induction.
• To investigate the predictability of spherical aberration induction in myopic LASIK.

Main Methods:

• Development of a theoretical foundation for ocular aberration analysis.
• Identification of a refractive surgical factor leading to a cubic function for postoperative asphericity.
• Formulation for calculating spherical aberration induction.
• Monte Carlo simulation of 1000 eyes for two surgical modalities.

Main Results:

• The Munnerlyn shape in myopic LASIK results in a prolate, not oblate, cornea, contrary to common belief.
• Postoperative spherical aberration levels are comparable between conventional and Q-preserved treatments.
• Conventional refractive surgery shows slightly higher predictability in inducing spherical aberration from the ablation target shape.

Conclusions:

• A theoretical framework aids in analyzing ocular aberration correction.
• Conventional refractive surgery offers a more predictable induction of spherical aberration compared to Q-preserved methods.
• The findings provide insights into optimizing refractive surgery for aberration control.