In Vivo Positional Analysis of Implantable Collamer Lens Using Ultrasound Biomicroscopy

Purpose. To evaluate the anterior segment, the anatomical position of the implantable collamer lenses (ICL), and its relationship to adjacent ocular structures using Ultrasound Biomicroscopy (UBM). Methods. In a prospective study, 142 myopic eyes of 93 patients implanted with Visian ICL were subjected to UBM examination between March 2010 and January 2015. The relative position of ICL to the adjacent structure and the overall iris configuration were evaluated. The machine calibers were used to measure the minimum central distance between the ICL and anterior lens capsule (vault) and the vertical central distance between the corneal endothelium and the ICL (E-ICL). Results. The mean ICL vault was 376±105 μm. The mean E-ICL was 2826±331 μm. Contact between ICL and the posterior epithelium of the iris was present in all eyes. The overall iris configuration was flat in 89 eyes. Central anterior convexity was present in 41 eyes and mild peripheral iris bombe in 12 eyes. The haptics could be imaged in the ciliary sulcus in 112 eyes and at least one haptic resting on the lens periphery and zonules in 30 eyes. Conclusion. UBM can provide valuable anatomical information that allows detailed postoperative in vivo assessment of ICL