Effects of different side-cut angles on ocular surface recovery after FS-LASIK

Area of Science:

• Ophthalmology
• Corneal Surgery
• Laser Vision Correction

Background:

• Femtosecond laser-assisted in situ keratomileusis (FS-LASIK) is a common refractive surgery.
• The corneal flap's side-cut angle may influence postoperative healing and ocular surface recovery.
• Optimizing surgical parameters is crucial for improving patient outcomes and reducing complications.

Purpose of the Study:

• To investigate the impact of different side-cut angles (45°, 90°, 135°) on ocular surface recovery after FS-LASIK.
• To compare corneal flap healing, sensation, dry eye symptoms, and nerve regeneration across varying side-cut angles.
• To determine the optimal side-cut angle for enhanced postoperative recovery.

Main Methods:

• A prospective, randomized study involving 99 patients (198 eyes) undergoing FS-LASIK.
• Patients were divided into three groups based on side-cut angles: 45°, 90°, and 135°.
• Evaluations included visual acuity, flap edge scar, corneal sensation, Ocular Surface Disease Index (OSDI) scores, and nerve fiber repair at multiple postoperative time points (10 days, 1 month, 6 months).

Main Results:

• The 90° side-cut angle group exhibited the lowest incidence of corneal flap edge healing scars (74.1%).
• Early postoperative corneal sensation (at 10 days) was highest in the 90° group.
• The 90° group showed the lowest OSDI scores throughout the follow-up period, indicating fewer dry eye symptoms. Scarless healing correlated with faster nerve repair.

Conclusions:

• The side-cut angle significantly affects postoperative ocular surface recovery in FS-LASIK.
• A 90° side-cut angle appears optimal, associated with reduced scarring, improved early sensation, and diminished dry eye symptoms.
• Utilizing a 90° side-cut angle may enhance ocular surface healing and patient comfort post-FS-LASIK.