LONG-TERM RESULTS OF EFFICACY AND SAFETY OF LENS VAULT FOLLOWING IMPLANTATION OF POSTERIOR CHAMBER IMPLANTABLE COLLAMER LENS.

Purpose: To describe and compare the efficacy and safety profile of posterior chamber Implantable Collamer Lens (ICL) implantation in eyes with low-vault and non-low vault over a five-year follow-up period.

Setting: Hospital de Braga, Braga, Portugal.

Design: Retrospective, comparative, cohort study of patients submitted to ICL V4c implantation for myopia correction, with a minimum follow-up of 5 years.

Methods: Two groups were created based on the first postoperative vault measurement evaluation (1 month): Group 1 (< 250 μm) and Group 2 (≥ 250 μm). Patients with previous ocular surgery or pathologies that would affect visual outcomes were excluded. The parameters evaluated were uncorrected and corrected visual acuity, subjective refraction, efficacy and safety index, predictability, endothelial cell density, central vault, and postoperative complications. One hundred seven eyes from 67 patients in group 1 and 289 eyes from 164 patients in group 2 were evaluated.

Results: At 5 years, the safety and efficacy index were similar (p=0.224 and p=0.390, respectively). Respectively, 80 (76.2%) and 201 (70.5%) eyes were within ±0.50 D of targeted refraction. There was a significant reduction in vault measurements in both groups (p=0.034 and p<0.001, respectively). No significant differences between groups in endothelial cell density loss were noted (p=0.096). The low-vault group presented a higher incidence of crystalline lens opacities/cataracts (5.6% versus 1.7%), although only one patient in group 2 was submitted to cataract surgery.

Conclusions: ICL implantation for surgical correction of myopia yielded stable visual results with excellent safety and efficacy indexes in patients with low vault.