Corneal light backscatter measured by optical coherence tomography after LASIK

Area of Science:

• Ophthalmology
• Biomedical Optics
• Corneal Surgery

Background:

• Laser-assisted in situ keratomileusis (LASIK) is a common refractive surgery.
• Assessing corneal healing and optical quality post-LASIK is crucial.
• Corneal light backscatter is an indicator of tissue microstructure and light scattering properties.

Purpose of the Study:

• To objectively quantify corneal light backscatter after LASIK using optical coherence tomography (OCT).
• To analyze changes in light scattering within different corneal layers and at the flap-bed interface post-LASIK.

Main Methods:

• Utilized a custom anterior segment OCT (1310 nm) to image 28 eyes before and at 1 day, 1 week, and 1 month after LASIK.
• Analyzed backscattered light from corneal epithelium, stromal layers, and the interface area using custom software.
• Compared interface light scattering to preoperative baseline values.

Main Results:

• Significant differences in light backscatter were observed across corneal layers and over time post-LASIK (ANOVA, P < .0001).
• Corneal light scattering significantly increased at the interface approximately 140-190 microm deep at 1 day and 1 week post-surgery.
• By 1 month post-surgery, epithelial scattering increased, while interface scattering decreased significantly.

Conclusions:

• Objective quantification of corneal light backscatter using OCT provides insights into post-LASIK healing.
• Corneal light scattering at the interface increases early after LASIK and subsequently recovers.
• OCT is a valuable tool for assessing microstructural changes and optical quality following refractive surgery.