Pharmacological Accommodative Changes of Haptic Position and Its Impact on Vault After ICL Implantation

Purpose To evaluate dynamic changes in ciliary parameters and Implantable Collamer Lens V4C (ICL) (STAAR Surgical) haptic position using mydriatic and miotic agents and their effects on the central and peripheral vault. Methods This study involved 80 eyes from 40 consecutive patients (mean age: 28.05 years; range: 19 to 42 years) examined 3 months after ICL implantation. Patients were randomly assigned to either a mydriasis group or a miosis group. Ultrasound biomicroscopy was used to measure the following parameters at baseline and after pharmacological induction with tropicamide or pilocarpine: ciliary process length (CPL), iris ciliary angle (ICA), final tip point of the ICL haptic (ftICL haptic), central vault (c-vault), mid-peripheral vault (m-vault), and peripheral vault (p-vault). Results In the mydriatic group, the proportion of eyes with all ICL haptics in the ciliary sulcus increased from 70.0% to 77.5% after tropicamide administration, whereas in the miotic group, this proportion decreased from 67.5% to 57.5% after pilocarpine administration. The CPL and ftICL haptic increased significantly in the mydriatic group (all P < .01) but decreased in the miotic group (all P < 0.01). Conversely, the ICA decreased significantly in the mydriatic group and increased in the miotic group (all P < .01). The correlation analysis showed no significant relationship between changes in c-vault, m-vault, and p-vault with alterations in CPL, ICA, and ftICL haptic in both groups. Conclusions Haptic position contributes to the movement of the ICL optical zone during accommodation, but changes in haptic position were not significantly correlated with changes in the vault. [ J Refract Surg . 2025;41(1):e22–e28.]