Long-term evaluation of anterior segment structures after implantable collamer lens V4c implantation

To evaluate the long-term outcomes of anterior segment parameters following implantable collamer lens (ICL V4c) implantation in highly myopic patients.

A tertiary specialized eye hospital in Shanghai, China.

Prospective, non-randomized, consecutive case series.

This study included 32 eyes of 20 patients with high myopia who underwent ICL V4c implantation with a 3-year follow-up. Preoperative assessments included standard biometry and anterior segment parameters. Postoperative evaluations were conducted at 1 day, 1 month, 3 months, and 3 years. Parameters assessed included corneal endothelium-anterior capsule distance (ACD-L), corneal endothelium-ICL distance (ACD-ICL), ICL-anterior capsule distance (ICL-L), anterior chamber angle (ACA) parameters, and iris metrics.

ACD-L decreased significantly postoperatively from baseline to 1 day (P < 0.001) but remained stable thereafter (e.g.,P = 0.397 between 1 day and 3 years). ACD-ICL increased over time, while ICL-L (vault) decreased significantly (P < 0.001), with the most pronounced changes occurring in the first month. All ACA parameters (ACW, AOD500, ARA500, TISA500, TIA500) decreased significantly compared to preoperative values (all P < 0.001) but showed no significant differences among postoperative follow-up points. Iris area (IA) and iris volume (IV) showed transient changes at 1 day post-surgery but returned to baseline levels thereafter (P = 0.302 for IA and P = 0.330 for IV at 3 years versus baseline).

During the 3-year follow-up of ICL V4c implantation, a gradual increase in ACD-ICL was significantly associated with vault reduction.