Anterior segment variations after posterior chamber phakic intraocular lens implantation in myopic eyes.

Purpose: To evaluate anterior segment variations after posterior chamber phakic intraocular lens (pIOL) implantation in myopic eyes.
Setting: Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.
Design: Cohort study.
Methods: Patients with high myopia were scheduled for nontoric Implantable Collamer Lens pIOL or toric Implantable Collamer Lens pIOL implantation. Anterior segment optical coherence tomography was performed to evaluate the anterior segment variations over time and the impact of physiologic accommodation and change in brightness after pIOL implantation. Slitlamp photography of the anterior segment was taken after pupil dilation to calculate pIOL rotation.
Results: There was significantly improved visual acuity and refractive status after implantation of both pIOLs. Anterior segment axial variations had good stability 6 months postoperatively. However, nontoric pIOL rotation occurred in 1 eye 7 months postoperatively and rotation of the toric pIOL occurred in 2 eyes at 3 months and 6 months. Stimulations of -4.0 diopters (D) and -8.0 D led to significant changes in anterior chamber depth (ACD) based on the lens (ACD-lens), ACD after pIOL implantation, distance between the pIOL posterior surface and the lens anterior surface (pIOL-lens), and pupil diameter. Increasing ambient light brightness could reduce the ACD-lens and pIOL-lens.
Conclusions: Both pIOLs had good axial stability in myopic eyes 6 months postoperatively; however, rotational stability over time could not be determined. The physiologic adjustment and change in brightness could influence the anterior segment significantly in eyes with a pIOL.
(Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)