Seven-Year Clinical Outcomes and Optical Quality of Implantable Collamer Lens Implantation Versus KLEx for Myopia...

This study aims to compare the seven-year clinical outcomes of Implantable Collamer Lens (ICL) implantation and keratorefractive lenticule extraction (KLEx) for the correction of myopia in patients with anisometropia, with a focus on evaluating long-term refractive stability, visual quality, and patient satisfaction.

Eye and ENT Hospital of Fudan University, Shanghai, China.

Retrospective contralateral eye comparative case series METHODS: The study encompassed 50 eyes from 25 myopic patients. The eye with the higher degree of myopia underwent ICL implantation, while the contralateral eye underwent KLEx surgery. Comprehensive preoperative evaluations included assessments of visual acuity, refractive error, corneal topography, and endothelial cell density. ICL V4c implantation and KLEx were performed following standardized surgical protocols. Postoperative follow-up evaluations at 1 month and 7 years included measurements of visual acuity, refractive stability, wavefront aberrations, retinal image quality, and patient-reported visual disturbances.

At the 7-year follow-up, both groups demonstrated high levels of safety visually and physiologically at 7 years, with safety indices of 1.23 ± 0.27 in the ICL group vs 1.08 ± 0.12 in the KLEx group, and endothelial cell density of 2654.96 ± 225.98 cells/mm² in the ICL group vs 2576.92 ± 241.78 cells/mm² in the KLEx group. Efficacy also presented high efficacy indices of 1.13 ± 0.22 in the ICL group and 0.95 ± 0.15 in the KLEx group. Refractive stability was maintained in both groups, although axial length increased marginal significantly in the ICL group (0.35 ± 0.33 mm vs. 0.21 ± 0.21 mm, P = 0.002). ICL exhibited superior visual outcomes, as evidenced by lower intraocular scattering (OSI: 1.13 ± 0.42 vs. 1.57 ± 0.62, P = 0.012) and a higher Strehl ratio (0.20 ± 0.03 vs. 0.16 ± 0.03, P = 0.024). KLEx was associated with lower whole-eye higher-order aberrations for a 3 mm pupil diameter (0.10 ± 0.06 µm vs. 0.12 ± 0.14 µm, P = 0.043). No significant differences were observed in disk halo size or pupil dynamics between the two groups.

Both ICL and KLEx are effective for long-term myopia correction, with ICL offering superior visual quality and stability, particularly in patients with high myopia. The combination of these techniques in anisometropic patients is feasible and provides a personalized treatment approach, ultimately enhancing overall visual outcomes and patient satisfaction.