Abstract
Purpose :
The cause of possible decline of corneal endothelial cell density in the cornea in the presence of intraocular lenses is still poorly understood. We postulate that cell loss might be associated to changes in the glucose concentration that is caused by variations of the aqueous humor flow in the anterior chamber. This hypothesis is tested by mathematically modeling the glucose transport and corneal metabolism in the anterior chamber with and without the presence of an iris-fixted intraocular lens (pIOL).
Methods :
We perform numerical simulations of corneal metabolism and transport processes in the anterior chamber, adopting idealized but realistic geometries. We focus our attention on the aqueous flow due to production/drainage that models the case of a person at sleep. In this case, flow induced by eye rotations and thermal effects is absent. In the case of pIOL we also consider the possibility of having a central hole in the lens body.
Results :
The concentration of glucose along the corneal endothelium is found to be significantly non-uniform even in the absence of a pIOL, but glucose flux across the endothelium is almost constant along its length. Implantation of a pIOL produces a decrease of glucose availability in the central region of the cornea. Even if the process of glucose consumption takes place over time scales that are longer than the typical interval between rapid eye movements, that would contribute to mix up the aqueous in the anterior chamber, low values of glucose concentration at the cornea are likely to occur.
Conclusions :
For a person at sleep nutrient concentration along the corneal endothelium can be significantly non-uniform. Implantation of a pIOL may produce a decrease of nutrient availability in the central region of the cornea, although it must be verified whether this has clinical relevance.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.