Long-Term 3-Dimensional Post-LASIK Epithelial Thickness Change and Remodeling
Narrative Responses:
Purpose
To evaluate epithelial thickness profile changes following myopic femtosecond-assisted LASIK in relation to the degree of myopia corrected, evaluated with a spectral-domain anterior-segment optical coherence tomography system.
Methods
61 consecutive cases that were subjected to femtosecond LASIK myopic correction were investigated for corneal epithelial thickness distribution both pre-operatively as well as one-day, one-week, one-month and one-year post-operatively. Epithelial thickness mapping over the 6 mm diameter corneal area was obtained with a commercially-available anterior-segment, spectral-domain optical coherence tomography (AS-OCT) system. Descriptive statistics investigated pre- and post-operative epithelial thickness up to one year at the central 2 mm, the average over the central 6 mm area, and mid-peripherally at the 5 mm ring area.
Results
Preoperatively, pupil center epithelial thickness was 51.67±2.57 (45 to 56) μm, mean 51.76±2.66 (45 to 57) μm, mid-peripheral 51.78±2.71 (46 to 57) μm. Epithelial thickness changed at the first postoperative day by -0.08, -0.34, and -0.39 μm, centrally, mean, mid-peripherally, then by -0.30, +1.07, +1.35 μm on the first week. On the first month appeared increased by +1.58, +2.88, and +3.31 μm (p=0.0036, <0.001, and <0.001), and after one-year +1.42, +2.90, and +3.19 μm, (p=0.146, <0.001, and <0.001). The correlation between epithelial increase at one-year and the amount of myopic correction showed a trend towards epithelial increase with myopic ablation.
Conclusion
This study suggests that there is a very significant correction of epithelial hypertrophy at one-month and over one-year postoperatively. This study suggests that there may be a very significant correlation of epithelial hypertrophy to degree of myopia corrected with LASIK.