**1. Introduction**

This work is part of the research group "Mass transfer in flexible porous medium" certified by the Federal University of Pernambuco - UFPE at the National Council for Scientific and Technological Development – CNPq, of the Ministério da Ciência, Tecnologia e Inovações (Ministry of Science, Technology and Innovation), of the Federal Government of Brazil. Physically, a flexible porous medium can be a cleaning sponge but it can serve as a model to demonstrate the mass transfer movement by forced convection in the cornea, lens, trabecular meshwork and retina, as well as muscles.

In the research it was found that in the experiments carried out by the German astronomer and Jesuit Christoph Scheinerque, in 1619, *apud* [1], with holes in a card, when observing the same object through different holes, different distances are perceived, corresponding to the intraocular lenses formed by dehydrated metabolic residue droplets [2]. That is, the card selects the image to be viewed in an overlay of images, which may be the astigmatism cause, in addition to myopia or hyperopia [3].

The research group leader exercises his own eyes to solve his eye refraction problems and discusses with the researchers group the understanding of the intraocular process of dehydration and rehydration of metabolic residue.

In this chapter we will show that the implantation technique known as IOL monovision, should be performed only if the patient accepts the act, after being informed, in writing, of the possible negative consequences that may occur to his health following cataract surgery. The difficulties in living with the symptoms acquired by a patient submitted to this surgical technique are presented, as well as the preoperative exams. Before surgery the patient was authorized by the doctor to renew his driver's license to drive motor vehicles without the use of corrective lenses.
