Analysis of intraocular positions of posterior implantable collamer lens by full-scale ultrasound biomicroscopy

BACKGROUND: To analyze the positions of intraocular posterior Implantable Collamer Lens (ICL) and its possible relationship with vault. METHODS: This cross-sectional study included 72 patients with high myopia (134 eyes) who were followed up after phakic intraocular lens implantation. The postoperative time ranged from 1 week to 7 years. We obtained the images of ICL by using Compact Touch STS UBM and observed the position of ICL in posterior chamber and ciliary sulcus. The horizontal lines vault was measured and recorded. RESULTS: There were various positions in the posterior chamber as observed by full-scale ultrasound biomicroscopy and the haptics were inserted at different positions. -Eight seven eyes (64.9%) that obtained ideal vault, 29 eyes (21.6%) had insufficient vaults and 18 eyes (13.4%) had excessive vault. The vault with various positions of haptics was in ideal range (250 μm–750 μm) almost in each group. Three eyes in this study with haptics on the top of ciliary sulcus obtained excessive vault (mean vault, 850.00 ± 70.71 μm) and one eye appeared one side haptics pushing forward the iris. Among five eyes (3.7%) with iridociliary body cysts, three eyes (60%) obtained ideal vault. One eye (0.7%) with ICL decentralization after implantation surgery had an ideal vault, but the patient had serious glare. CONCLUSIONS: Though ICL in the posterior chamber had different positions and the haptics in most cases were not in the ciliary sulcus, the postoperative vault was almost in the ideal range.