Numerical simulation of aqueous flow in a novel posterior chamber phakic intraocular lens versus its counterparts

Abstract

Phakic intraocular lenses (pIOLs), particularly posterior chamber pIOLs, are becoming important for patients with high myopia and thin corneas. By phakic intraocular, we mean the ocular environmental conditions, where the natural lens is unremoved. A new posterior chamber pIOL, the sine wave phakic refractive lens (SW-PRL), is in the development stage, and its aqueous humor (AH) dynamics and the effects of intraocular geometry on the flow characteristics are not well understood. To analyze the adaptability and functionality of SW-PRL, a comparison study is made with its counterparts, the posterior chamber phakic refractive lens (PC-PRL), PC-PRL combined with peripheral iridotomy [PC-PRL(PI)], and implantable collamer lens with a central hole (ICL V4c). The result demonstrates that SW-PRL has a positive effect on AH flow circulation. Interestingly, there is a relationship between a posterior chamber flow and the type of pIOLs with vault variation. With an increase in vault, the flow between the lens and pIOLs slowed down after ICL V4C implantation but accelerated after PC-PRL (PI) implantation with little change after SW-PRL implantation. On the rear surface of the iris, the wall shear stress (WSS) was lower for PC-PRL(PI), SW-PRL, and ICL V4c (5.6 × 10−4, 6 × 10−3, and 8.2 × 10−3 Pa, respectively) compared to the PC-PRL (0.14 Pa), and on the front surface of lens, the WSS was lower for PC-PRL and SW-PRL (1.16 × 10−5 and 9.7 × 10−6 Pa, respectively) compared to the ICL V4c (8.2 × 10−4 Pa). WSS on the cornea surface was similar for each pIOL. These might provide a fresh viewpoint on the clinical decision of different intraocular lenses.