Predictive Factors For Vault After Icl-V4c Implantation In Eyes With Ultrahigh Myopia Above - 15 D

To identify preoperative biometric predictors of postoperative vault in eyes with ultrahigh myopia (spherical equivalent [SE] ≤ -15D) following Implantable Collamer Lens V4c (ICL V4c; STAAR Surgical) implantation.

Retrospective cohort study.

This study included 106 eyes from 86 patients categorized by SE: Group A（-15D ≤ SE < -10D, n=54) and group B (SE ≤ -15D, n=52). Biometric parameters, including axial length (AL), anterior chamber depth (ACD), keratometry (K1, K2), anterior radius of curvature (ARC), lens thickness (LT), central corneal thickness (CCT), central lens vault (CLV) and peripheral lens vault (PLV) were collected. Multivariate linear regression models were used to analyze the relationship between these variables and postoperative vault.

Group B exhibited significantly longer AL, thicker LT, smaller ARC, and lower PLV compared to Group (all P < 0.001). Regression analysis identified ARC (β = 0.04, p < 0.001) and CLV (β = 0.64, p < 0.001) as independent predictors of PLV.

In eyes with SE ≤ -15D, lower CLV and steeper ARC are key determinants of lower postoperative peripheral vault, potentially increasing the risk of contact between the ICL and the crystalline lens. Preoperative assessment of these parameters may optimize ICL sizing in ultrahigh myopia.