Eyeworld

26 | EYEWORLD | SEPTEMBER 2022 ASCRS NEWS of which lost CDVA after treatment. Notably, a greater pre-enhancement time interval was not associated with increased EI. This study also could not confirm the previously suggested asso- ciation between patient age and EI. 21 This study suggests that loose epithelium may have been associated with epithelial ingrowth. However, this is often not clearly documented and needs further study. A microkeratome flap may theoretically have a higher EI risk compared to a femtosec- ond laser flap due to the >90-degree side cut angle. This same attribute may also decrease scarring and increase the ease of flap relift com- pared to a femtosecond laser flap. Interestingly, there were no significant differences in relift success and EI incidence between the two tools. The flap relift method itself may also influence EI incidence. The authors were concerned that using a probe at 180 degrees from the hinge and lifting the rest of the flap with forceps may lead to greater rates of EI. Therefore, they instead created an opening at the flap margin with a sharp needle into which a spatula was used to cleave and lift the flap. They hoped this method would decrease the number of epithelial cells introduced under the flap. The study is limited by short follow-up, poor documentation of loose epithelium prior to relifting, and lack of a clear definition of EI with which to compare with other studies. It is also limited by sample size factors that made com- parison of variables (sex, flap creation method, successful vs. unsuccessful lifts) difficult. Lastly, this study's inclusion of all EI cases makes it appear to have a higher EI incidence compared to other papers that only report clinically signifi- cant EI. Conclusion According to this study, LASIK enhancement via flap relifting can be safe years after primary LASIK treatment. It may have fewer compli- cations compared to alternatives like surface ablation or recutting. Clinically significant EI is rare and does not cause vision changes after it was removed. The authors also showed that previously suggested risk factors for EI like pre-enhancement time interval, flap creation tool, sex, and age were unsupported. This is the largest retrospective study to date that exam- ines LASIK flap relifting and describes a specific surgical technique with low complication rates. The authors present a compelling argument for flap relifting to become the preferred method for LASIK enhancement many years after prima- ry treatment. References continued 1 13. Randleman JB, Shah RD. LASIK interface complications: etiology, management, and outcomes. J Refract Surg. 2012;28:575–586. 14. Wang MY, Maloney RK. Epi- thelial ingrowth after laser in situ keratomileusis. Am J Ophthalmol. 2000;129:746–751. 15. Letko E, et al. Influence of original flap creation method on incidence of epithelial ingrowth after LASIK retreatment. J Refract Surg. 2009;25:1039–1041. 16. Caster AI, et al. Incidence of epithelial ingrowth in primary and retreatment laser in situ ker- atomileusis. J Cataract Refract Surg. 2010;36:97–101. 17. Henry CR, et al. Epithelial ingrowth after LASIK: clinical char- acteristics, risk factors, and visual outcomes in patients requiring flap lift. J Refract Surg. 2012;28:488–492. 18. Ting DSJ, et al. Epithelial ingrowth following laser in situ keratomileusis (LASIK): prevalence, risk factors, management and visual outcomes. BMJ Open Ophthalmol. 2018;3:e000133. 19. Durrie DS, Aziz AA. Lift-flap retreatment after laser in situ keratomileusis. J Refract Surg. 1999;15:150–153. 20. Walker MB, Wilson SE. Incidence and prevention of epithelial growth within the interface after laser in situ keratomileusis. Cornea. 2000;19:170–173. 21. Chan CCK, Boxer Wachler BS. Comparison of the effects of LASIK retreatment techniques on epithelial ingrowth rates. Ophthalmology. 2007;114:640–642. continued from page 25 Effect of time since primary laser-assisted in situ keratomileusis on flap relift success and epithelial ingrowth risk Chang JSM, et al. J Cataract Refract Surg. 2022;48:705–709. n Purpose: To assess the association of time since primary laser-assisted in situ keratomileusis (LASIK) with flap relift success and risk for epithelial ingrowth (EI) in eyes undergoing flap relift after primary LASIK n Setting: Hong Kong Sanatorium & Hospital, Hong Kong Special Administrative Region n Design: Retrospective observational case series n Methods: 73 eyes with flaps relifted for refractive enhancement LASIK were included. Main outcome measures included rate of relift success and EI; associations of time since primary LASIK, sex, age at relift, year of relift, and flap creation method in primary LASIK with relift success and EI n Results: Of the 73 eyes included, relifting was successful in 71 eyes (97.3%). Among the successfully relifted eyes, 12 (16.9%) developed EI, of which 3 (4.2%) were clinically significant. No eyes lost more than 1 line of corrected distance visual acuity. The time since primary LASIK (up to 22 years), sex, age at relift, year of relift, and flap creation method in primary LASIK were not associated with relift success or EI. n Conclusion: With the described surgical technique, flaps could be successfully relifted without much difficulty up to 22 years after primary LASIK with a low incidence of EI. Contact Mai: Anthony.Mai@hsc.utah.edu Murri: Mike.Murri@hsc.utah.edu Pettey: jeff.pettey@hsc.utah.edu

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