Visual outcomes in refractive surgery outlier candidates
Pochat, Christopher Andrew
MetadataShow full item record
BACKGROUND: Refractive surgery has become a popular method of treating and reducing refractive errors. Some of the most common types of corneal-based refractive surgery are Laser In Situ Keratomileusis (LASIK), Laser Epithelial Keratomileusis (LASEK), and Photorefractive Keratectomy (PRK). Advanced Surface Ablation (ASA) is an umbrella term which refers to both LASEK and PRK. The current literature lacks analysis of high refractive errors with controls. OBJECTIVES: To fill gaps in the current literature regrading outliers with high refractive errors by comparing their outcomes to those with low-moderate refractive errors. Additionally, to determine if LASIK or ASA offers superior results for those with high refractive errors and to determine those with different high refractive errors have similar refractive surgery outcomes. METHODS: A retrospective chart review identified 46 eyes with a preoperative spherical component ≤ -8.50D, 63 eyes with preoperative spherical component ≥ + 3.50D, and 54 eyes with a preoperative cylindrical component ≥ -3.50D which met the criteria for inclusion in the high refractive error cohorts. Each eye was age-matched to a control with a low-moderate amount of its respective refractive error. Quantitative variables were analyzed with t-tests and single-factor analysis of variance. Qualitative variables were analyzed with chi-squared tests. Postoperative uncorrected distance visual acuity (UCDVA) was used as the primary determinant of visual outcomes and postoperative best corrected visual acuity (BCDVA) was used as the secondary determinant of visual outcomes. Postoperative manifest refractions supplemented the analysis. Changes in BCDVA between pre- and postoperative measurements, with particular attention to loss of Snellen lines, were used as determinants of safety. RESULTS: The postoperative UCDVA and BCDVA of the myopia cohort was significantly worse than that of the myopia control group (p = 0.038 and p = 0.0029). There was no significant difference the safety profiles of the myopia cohort and control group (p = 0.99). The postoperative UCDVA of the hyperopia cohort was significantly worse than that of the hyperopia control group (p = 0.0069). There was no significant difference in the safety profiles of the hyperopia cohort and control group (p = 0.96). The postoperative UCDVA of the astigmatism cohort was significantly worse than that of the astigmatism control group (p = 0.0014). There was no significant difference the safety profiles of the myopia cohort and control group (p = 0.99). There was no difference between postoperative UCDVA and BCDVA between the cohorts. Neither LASIK nor ASA were superior to the other in terms of UCDVA or BCDVA for all of the cohorts. CONCLUSION: Refractive surgery, while safe, is not as effective for those requiring high amounts of visual correction compared to those requiring low amounts. Neither surgery type, LASIK nor ASA, offer superior results to those with high refractive errors.
RightsAttribution-NonCommercial 4.0 International