Physiology of Vitreous and Vitreomacular Interface and Age-Related Changes

Abstract

Vitreous is an important ocular structure in the normal physiology and pathologic conditions of the posterior segment. Vitreous is a gel-like composite structure and forms an extracellular matrix that occupies the biggest space in the eye. The healthy vitreous gel reduces oxygen tension and protects vitreous, retina, and lens from oxidative damage. Vitreous plays an important role in the refraction of the eye, preserving the transparency with regular interaction of the macromolecules contained therein. Vitreous suffer from continuous physical tension and this results in important changes. Particularly age-related degeneration in the structure of the vitreous gel leads to a decrease in vitreoretinal adhesion. As part of natural aging, the posterior vitreous detachment process may become pathologic when the vitreoretinal interface weakens simultaneously with vitreous liquefaction. In this process, vision-threatening diseases such as vitreomacular adhesion, vitreomacular traction, and macula hole may appear.