Biometric and ICL-related risk factors associated with suboptimal vault with implantable collamer lenses
TL;DR
Low vault is independently associated with greater CLR, whereas high vault is independently linked to deeper ACD and higher SE, and underscores the importance of integrating CLR and ATA measurements into routine preoperative assessment.
Abstract
Background To comprehensively explore the biometry related to suboptimal vault (including low and high vault) after implantable collamer lens (ICL) implantation and the risk factors associated with ICL. Methods This retrospective case-control study enrolled 180 patients with myopia and astigmatism who underwent EVO-V4c ICL implantation at Peking Union Medical College Hospital between January 2023 and December 2024. The normal vault group (NVG) was randomly selected from eligible patients during the same period to ensure balanced group sizes and reduce selection bias. Patients were divided into three groups based on the postoperative vault: low vault group (LVG, <250 μm, n = 36), high vault group (HVG, >750 μm, n = 72), and normal vault group (NVG, 250–750 μm, n = 72). Biometric parameters were collected before and after surgery for all patients, including anterior chamber depth (ACD), white-to-white (WTW), angle-to-angle (ATA), crystalline lens rise (CLR), axial length (AL), and spherical equivalent (SE). Multivariate analysis of variance (MANOVA), Pearson correlation analysis, multiple linear regression, and logistic regression analysis were employed to assess the relationship between each parameter and postoperative vault outcomes. Results The results indicated significant differences in age, ACD, WTW, ATA, AL, and CLR among the three groups of patients (P < 0.05). Multivariate linear regression analysis revealed that ACD (P < 0.05), CLR (P < 0.001), and ATA (P = 0.018) were independent factors affecting postoperative vault. Logistic regression analysis showed that higher CLR (OR = 1.008, P = 0.013) was an independent risk factor for low vault, while deeper ACD (OR = 1.477, P = 0.030) and more negative ICL spherical equivalent (ICLSE, OR = 0.523, P = 0.034) were independent risk factors for high vault. Conclusions Low vault is independently associated with greater CLR, whereas high vault is independently linked to deeper ACD and higher SE. Age, WTW, ATA, and AL also demonstrate significant but varying associations with vault type. These findings underscore the importance of integrating CLR and ATA measurements into routine preoperative assessment. Employing a more individualized sizing strategy—particularly in patients with deeper ACD or pronounced CLR—could enhance vault predictability and improve postoperative safety.