Brillouin assessment of the crystalline lens in patients with high myopia after long-term implantable collamer lens V4c implantation

Purpose: To evaluate the long-term effects of implantable collamer lens (ICL) V4c on the biomechanical and morphological properties of crystalline lenses in Chinese adults with high myopia using Brillouin microscopy (BM).

Methods: In this case-control study, 102 highly myopic eyes from 102 patients (18-48 years, preoperative spherical equivalent (SE): -6.00--21.00 D) were categorised into ICL and control groups, matched by age, axial length (AL), lens thickness (LT) and preoperative SE. The biomechanical and morphological properties of the lenses were measured by BM. Ocular and anterior segment parameters, including AL, anterior chamber depth, volume, angle and LT, were assessed using Pentacam and IOL Master 700.

Results: No significant differences were observed in Brillouin morphological parameters between the ICL and control groups, including the width of top plateau (WTP), width of bottom plateau (WBP), bottom-top (B-T), slope of anterior cortex (SAC), and slope of posterior cortex (SPC) (all p > 0.05). A slight decrease in biomechanical metrics (height of plateau, Height) was observed in the ICL group, compared with the control group (p = 0.012). Linear regression analysis revealed age-related changes in morphological metrics among all participants, including WTP (p = 0.0001), WBP (p = 0.0001), and SPC (p < 0.0001), while B-T and SAC were age-independent (both p > 0.05). No age-related changes in Height were observed (p > 0.05).

Conclusions: ICL V4c did not significantly alter lens morphology as assessed using BM. A slight decrease in lenticular biomechanics was observed after ICL implantation.