The Impact Of Size And Position Of Implantable Collamer Lens (Icl) On Vault

This study aims to investigate the impact of different ICL models and implantation positions on postoperative vault.

Postoperative vault is one of the most critical safety indicators following ICL implantation surgery. It is widely accepted that an ideal vault height ranges from 250 to 750 μm, equivalent to 0.5 to 1.5 times the corneal thickness. Accurate preoperative prediction of vault remains a key focus in current clinical research.

A retrospective analysis was conducted on patients who underwent ICL implantation surgery at our hospital from December 2020 to December 2024. Patients were divided into three groups: Group A (both eyes implanted with the same ICL model), Group B (both eyes implanted with different ICL models), and Group C (both eyes implanted with the same ICL model but at different positions, horizontal vs. vertical). Postoperative vault height was compared among these groups.

 A total of 148 eyes were included,with 60 eyes in Group A,60 eyes in Group B, and 28 eyes in Group C.In Group A,the mean vault in the right eye was 592±212 μm and in the left eye was 596±222 μm on 6 month(P>0.05).In Group B,the mean vault for larger size ICL was 853.3±355.1 μm, and for smaller size ICL was 454.0±267.2 μm, with a difference of 399.3 μm on 6 month(P<0.01).In Group C,the mean vault for horizontally positioned ICL was 827.6±263.1 μm, and for vertically positioned ICL was 396.7±118.2μm,with a difference of 430.9 μm on 6 month.(P<0.01).All three groups exhibited a trend towards hyperopia in refraction on postoperative day 1 (P<0.05)

Our study demonstrates that both the size and position of ICL significantly influence vault.Excessive vault may affect the refractive index of the ICL, leading to a tendency towards positive refractive error.As vault decreases over time, the refractive error shifts from hyperopia to myopia.Vault should be considered in the personalized design of ICL implantation.