Effect of Accommodation on Vaulting and Movement of Posterior Chamber Phakic Lenses in Eyes with Implantable Collamer Lenses

Purpose To investigate and compare vaulting and movement changes during accommodation in eyes with the V4c and V4 implantable collamer lenses (ICL). Design Comparative, observational case series. Methods The medical records of 35 eyes (18 patients) with the V4 ICL and 51 eyes (26 patients) with the V4c ICL were retrospectively examined and included in analyses. Anterior chamber depth (ACD), posterior corneal surface-to-ICL distance (endo-ICL distance), pupil size, and postoperative vaulting were evaluated using the Visante anterior chamber optical coherence tomography system. Images were taken during the nonaccommodative and accommodative states 3 months after ICL implantation. Refractive error, keratometry values, axial length, intraocular pressure, and central corneal thickness were evaluated at 3 months postoperatively. Results ICL vaulting did not significantly change during accommodation in eyes with either the V4 or V4c ICL (P =.532 for V4 ICL and P =.415 for V4c ICL). However, significant reductions in ACD, endo-ICL distance, and pupil size were observed during accommodation in both groups. In eyes with a V4 ICL, the change in [Δ] ACD was 0.2 ± 0.1 mm (P <.001), Δendo-ICL distance was 0.2 ± 0.1 mm (P <.001), and Δpupil size was 0.5 ± 0.9 mm (P =.021). For eyes with the V4c ICL, ΔACD was 0.2 ± 0.2 mm (P <.001), Δendo-ICL distance was 0.2 ± 0.2 mm (P <.001), and Δpupil size was 0.8 ± 1.2 mm (P <.001). The mean reductions of each parameter were not statistically different between eyes with the V4 ICL and the V4c ICL. Conclusions Contrary to the light stimulation response, accommodation does not significantly affect ICL vaulting differently in eyes with either the V4 or V4C ICLs.