The tears that coat the surface of your eyes have both a liquid and a mucous layer to them. It is normal to have a small amount of mucus in your tear film. But that mucus can significantly increase when the eye gets irritated.

Some of the most...

A wrinkle on the retina -- which is also known as an epiretinal membrane (ERM) or a macular pucker -- is a thin, translucent tissue that develops on the surface of the retina.

The retina is the inner layer that lines the inside of the back of...