Accommodative tissues influence the shape of the cornea and potentially drive corneal morphogenesis

Abstract

This study investigates whether the presence of accommodative tissues biomechanically influences the shape of the cornea and potentially drives corneal morphogenesis during embryonic ocular development. Porcine eyes were subjected to an internal pressure simulating intraocular pressure. Ocular geometry was evaluated using a corneal topographer and digital cameras before and after dissection of the accommodative tissues. A computational model of the porcine eye was constructed and loaded by an internal pressure representing intraocular pressure. Eye shape was evaluated in models with and without the ciliary body. The porcine model was generalized to the human model, simplified model, or embryonic model with different ocular tissue shapes, sizes, and stiffnesses. Experimental data showed that, even in the six-month-old pig eye, the average corneal radius of curvature increased after the removal of accommodative tissues compared to sham controls (p = 0.002). Computational results agreed with the experimental data and further suggested that the change in corneal radius is greater when the tissue stiffness is low and the intraocular pressure is high, regardless of the geometry and size of the eye components. Using a combined in vitro and in silico approach, this study explores the biomechanical influence of the accommodative tissues and related loads on the cornea and offers additional factors that might influence the shape of the cornea.

Keywords: Accommodative tissues; Computational models; Cornea; Curvature; Morphogenesis.