The retina is the nerve layer that lines the back of the eye. If you think of the eye as a camera, the retina is the film in the camera. A clear gel called the vitreous fills up the inside cavity of the eye and is located just in front of the retina. As one ages, the vitreous gel contracts and liquefies. As this occurs, the vitreous gel may sometimes pull a tear in the retina. Fluid from inside the eye can leak through the tear, and the retina can separate from the back wall of the eye, creating a retinal detachment.
It is a serious condition that may lead to blindness if not treated appropriately. Risk factors for retinal detachment include nearsightedness (myopia), history of cataract surgery, family history of retinal detachment, retinal detachment in the other eye, and weak areas in the retina such as lattice degeneration. Symptoms of a retinal detachment include onset of floaters, flashing lights, and a “curtain” or area of darkness that may encroach on vision from the side.
The middle of our eye is filled with a clear gel called vitreous (vi-tree-us) that is attached to the retina. Sometimes tiny clumps of gel or cells inside the vitreous will cast shadows on the retina, and you may sometimes see small dots, specks, strings or clouds moving in your field of vision. These are called floaters. You can often see them when looking at a plain, light background, like a blank wall or blue sky.
As we get older, the vitreous may shrink and pull on the retina. When this happens, you may notice what look like flashing lights, lightning streaks or the sensation of seeing “stars.” These are called flashes.