Fifteen-year follow-up of implantable collamer lens surgery in high myopia: Complications, cataract surgery outcomes, and ultrastructural analysis.

PURPOSES: This study reports 15-year outcomes of implantable collamer lens (ICL) surgery in patients with high myopia, analyzing complications, efficacy of cataract surgical, and ultrastructural mechanisms of anterior subcapsular cataract (ASC).

METHODS

This retrospective study included 1208 eyes (ICL V4) and 6258 eyes (ICL V4c) from Eye & ENT Hospital of Fudan University, Shanghai, China. Follow-ups occurred preoperatively, at 1/3/6 months, annually post-ICL, and 1 month post-cataract surgery. Lens opacity, ASC rates, and complications were evaluated. Anterior capsule ultrastructure was assessed using scanning/transmission electron microscopy (SEM/TEM).

RESULTS

The ICL V4 group (follow-up: 23.12 ± 32.06 months) exhibited higher complication rates than V4c (8.95 ± 17.40 months): lens opacity (6.46% vs. 0.16%), ASC (2.32% vs. 0.10%), and bilensectomy (3.89% vs. 0.16%). Bilensectomy improved corrected distance visual acuity from 0.56 ± 0.39 to 0.34 ± 0.51 logMAR (P = 0.006), restoring pre-ICL levels (P = 0.310), with safety/efficacy indices of 1.08 ± 0.11 and 0.99 ± 0.08. Myopia-related complications included myopic macular atrophy (0.38%), choroidal neovascularization (0.24%), and retinal detachment (0.04%). SEM/TEM revealed lens epithelial cell proliferation, fibronectin or collagen deposition, and mitochondrial abnormalities (thickened cristae, perinuclear vacuolization) in ASC cases.

CONCLUSIONS

Super high myopia, shallow anterior chamber depth, and older age are key risk factors for post-ICL cataract. While bilensectomy restores vision, high myopia-related complications persist. ASC pathogenesis involves mechanical damage and metabolic dysfunction, evidenced by ultrastructural changes. These findings underscore the need for long-term monitoring in ICL patients with high myopia.