[Bilateral surgery: an efficient manner of creating LASIK nomograms]

Area of Science:

• Ophthalmology
• Refractive Surgery
• Surgical Technology

Background:

• Laser-assisted in situ keratomileusis (LASIK) nomograms are crucial for predictable refractive outcomes.
• Bilateral LASIK surgery offers an efficient platform for nomogram development and validation.
• Evaluating new ablation patterns requires rigorous comparison with established methods.

Purpose of the Study:

• To describe an efficient and predictable method for developing LASIK nomograms using bilateral surgery.
• To evaluate a novel randomized ablation pattern compared to an older sequential pattern in LASIK.
• To assess the impact of a new ablation software on refractive outcomes.

Main Methods:

• A cohort of sixteen patients undergoing bilateral LASIK was randomized to receive either a new or older ablation pattern.
• Surgical and refractive settings were kept consistent between eyes within each patient.
• Refractive outcomes were analyzed at 4 weeks and 6 months using statistical tests (Student T test, two-way ANOVA).

Main Results:

• Pre-operative spherical equivalents were similar between eyes.
• Post-operative analysis revealed significant overcorrection in the eye treated with the new randomized ablation pattern at 4 weeks (p < 0.05) and 6 months (p < 0.05).
• Cylinder correction was not significantly different between the two ablation patterns.

Conclusions:

• The new randomized ablation pattern resulted in significant overcorrection compared to the older sequential pattern in bilateral LASIK.
• Nomogram adjustments are necessary to compensate for the overcorrection induced by the new ablation pattern.
• Four weeks post-operatively is sufficient to evaluate refractive outcomes, as no significant differences were observed at 6 months.