LASIK vs transepithelial PRK for the treatment of hyperopia with astigmatism

Author Block: Muhammad Tariq ¹, Ahmed Al-Ghoul².  ¹²University of Calgary.

Author Disclosure Block: M. Tariq:  None.  A. Al-Ghoul:  None., Muhammad Tariq: Not Current  Ahmed Al-Ghoul: Not Current

Abstract Title: LASIK versus Transepithelial PRK for the Treatment of Hyperopia with Astigmatism

Abstract Body: Purpose:  To compare outcomes of Transepithelial PRK (TransPRK or tPRK) and LASIK for the treatment of eyes that had preoperative hyperopia with astigmatism.  Study Design:  Retrospective comparative study of outcomes for eyes with preoperative hyperopia with astigmatism for TransPRK and LASIK operations from January 21st, 2017, to July 8th, 2020. Schwind Amaris 750 laser was used for all cases. Eyes included in the study were those that had hyperopia and astigmatism on preoperative manifest refraction and provided postoperative data at least 5 months or more. 11 TransPRK operations and 27 LASIK operations were included in the study.  Methods:  Postoperative parameters such as SPH (sphere), CYL (cylinder), SE (Spherical Equivalent), regression, enhancement rate, BCVA (best-corrected Visual Acuity), and UCVA (uncorrected Visual Acuity) of eyes included in the study that underwent TransPRK were compared to those that underwent LASIK.  Results:  The difference in mean Post-Op SPH and Post-Op CYL of eyes that had undergone tPRK as opposed to LASIK were both found to be statistically insignificant (p=0.15 for SPH, p=0.18 for CYL). The mean (SD) postoperative SE for tPRK was -0.34D (0.22) and -0.03D (0.36) for LASIK, this difference was found to be significant (p=0.0068). No cases required enhancement in the post-operative duration observed. Regression analysis showed the Coefficient of Determination (R2) to be 0.96 for tPRK and 0.97 for LASIK. Correlation analysis of SE Correction Intended vs Correction Achieved was strong for tPRK (p<0.05) and LASIK (p<0.05). All eyes achieved SE of ±0.75 or better and UCVA of 20/30 or better. All eyes that received tPRK improved or maintained UCVA, as opposed to 96% for LASIK.  Conclusions:  Our study demonstrated favorable postoperative outcomes and stability for the treatment of hyperopia with astigmatism using Transepithelial PRK and LASIK. Both procedures were observed to be safe with very low enhancement rates needed.