A retinal tear takes place when the vitreous in the eye separates from the retina as we age, but does not do so cleanly.
The retina is a thin layer of nerve tissue lining the inside of the back of the eye. Light that enters your eye through the pupil is focused by the lens onto the retina. This causes signals to be sent along the optic nerve to the brain where they are interpreted into the images you see.
The main space in the centre of the eye contains a gel called vitreous. As we age this gel becomes less transparent and shrinks away from the retina at the back of the eye. This is called posterior vitreous detachment, or PVD and is absolutely normal. It can affect around seventy percent of people over the age of sixty five. PVD may create a problem with floaters, but alone it will not cause any permanent loss of vision.
Sometimes the gel does not separate cleanly from the retina and will stick to and pull the retina. In some cases, this can rip the retina creating a ‘retinal tear’.