Utilising VISULYZE-Generated Nomograms and OcuLign Alignment Tools to Improve Keratorefractive Lenticule Extraction Outcomes

Background: The keratorefractive lenticule extraction (KLEx) procedure has gained popularity because of its safety and effectiveness; however, its predictability remains variable, as it may be over- or under-corrected. This study aimed to evaluate visual and refractive outcomes following the utilisation of VISULYZE-generated nomograms (Carl Zeiss Meditec AG, Jena, Germany) and OcuLign cyclotorsion alignment tools (Carl Zeiss Meditec AG, Jena, Germany). Methods: This retrospective consecutive cohort study included patients undergoing KLEx, grouped into four sequential treatment phases: PRE-NOMOGRAM, NOMOGRAM, OCULIGN & NOMOGRAM, and OCULIGN. Results: A total of 688 patients (1264 eyes) were included. The OCULIGN group showed numerically higher efficacy, with 83.0% achieving post-operative (PO) uncorrected distance visual acuity (UDVA) 20/20 or better, with no loss of corrected distance visual acuity (CDVA) lines, and 67.0% gaining one line. Predictability and accuracy were high across groups, with the OCULIGN group demonstrating a strong correlation between attempted and achieved spherical equivalent (R2 = 0.9908), and 95.5% of eyes within ±0.50 D. Early PO outcomes suggested minimal refractive shift at one month. The NOMOGRAM group demonstrated numerically improved astigmatism correction (100.0% within ≤0.50 D), while the OCULIGN & NOMOGRAM group showed high precision in axis alignment. However, baseline imbalances were present, and between-group differences were relatively small. Conclusions: The use of OcuLign cyclotorsion alignment and VISULYZE-generated nomograms was associated with favourable visual and refractive outcomes following KLEx. However, given the retrospective, sequential design, imbalanced baseline, and limited follow-up duration, these findings should be interpreted cautiously. Further prospective, randomised studies with longer follow-up are required to confirm these observations.