Title : Visual functions and anterior ocular surface changes post-trans-epithelial photo refractive keratectomy
Abstract:
Purpose: To assess the impact of Trans-PRK on visual acuity, contrast sensitivity, spherical aberration, tear stability, corneal surface and thickness.
Method: A quantitative, comparative, and prospective case study was conducted in the Kingdom of Saudia Arabia after receiving the proper ethical clearance. Eighty-six consenting volunteers aged between 18 and 40 years old, including both genders, were enrolled in the study. Participants, grouped according to the period they spent after their post-operative visits. A LogMAR chart used to measure VA, contrast sensitivity was assessed using a Pelli-Robson test chart, while spherical aberration and corneal topography and thickness were measured with SCHWIND SIRIUS. Schirmer ? test and TBUT were conducted to assess tear stability. The Statistical Package for Social Sciences (SPSS) software version 27 (IBM Corporation) was used to conduct descriptive and comparative data analysis applying one-way ANOVA and paired t-tests.
Result: There was a significant increase in contrast sensitivity 0.00 (p<0.005), and visual acuity with the post-operative mean best corrected visual acuity (BCVA) being 0.00 Log MAR for all groups. CCT was significantly thinner (p=0.000) and significant corneal flattening occurred (p<0.005) in all study groups. Spherical aberration improved significantly only in participants returning after one year (p=0.000). TBUT remained stable in all groups whilst tear volume decreased significantly in group 1 (p=0.000) and group 3 (p=0.013) only.
Conclusion: Trans-PRK improves visual acuity, contrast sensitivity, causes significant corneal thinning and flattening. Spherical aberration improved after one-year post-surgery, TBUT does not change after Trans-PRK. While tear volume decreased.
