[Retreatment after keratorefractive lenticule extraction (KLEx) : Results of various methods and influence of the recommendations of the Committee for Refractive Surgery (KRC) on the incidence of retreatment].

Background: Keratorefractive lenticule extraction (KLEx) has been shown to be safe and effective for the correction of myopia and myopic astigmatism. Residual refractive errors reduce the uncorrected postoperative visual acuity leading to patient dissatisfaction and increased retreatment rates.

Aim Of The Study: The aim was to assess the potential influence of the recommendations of the Committee for Refractive Surgery (KRC) on the likelihood of retreatment and to compare the results of various methods for retreatment after KLEx for myopia.

Methods: Retrospective study of eyes with myopia and myopic astigmatism in which KLEx (SMILE, Visumax 500, Carl Zeiss Meditec, Jena, Germany) was performed between April 2015 and December 2022.

Results: A total of 2462 eyes from 1278 patients were analyzed. Of the eyes 3.05% (n = 75) were retreated within 24 months. Eyes in the recommended treatment range (corrections up to -8.0 dpt in the stronger main section) had a 50% lower risk of retreatment than eyes within the borderline range (corrections between -8.0 dpt and -10.0 dpt in the stronger main section). Retreatment was predominantly performed using the advanced surface ablation (ASA n = 44) or the Circle program (transformation of a SMILE cap into a flap, n = 29). The postoperative results of both methods after 3 months were comparably safe and effective; however, visual recovery was significantly faster with Circle. A second KLEx treatment in two eyes (one patient) resulted in a residual refractive error, which impaired the uncorrected visual acuity even 1.7 years later.

Conclusion: There was a significantly lower retreatment rate in the recommended treatment range than in the borderline range according to the KRC recommendations. In addition, the ASA and Circle proved to be equally predictable but with different healing processes. These results can help with the education and selection of patients.