is a clear, thin light sensitive tissue in the back of the eye. It is made up of layers of nerve cells that arrive from the optic nerve through the back of the eye. The fibers spread out from the center of the optic nerve in every direction (kind of like the leaves in a sunflower spread out from the center of the sunflower) and it is these fibers, one on top of another, that make the retina. The retina is firmly attached to the back of the eye in very few places; most of the retina is "tacked" down only by the pressure inside of the eye. Because it is thin and pliable and because it is not firmly in place, it is susceptible to having tears and holes, and these defects can cause the thin tissue of the retina to pull off the back of the eye. This is termed "detachment". Certain people are more prone to having retinal detachments than others. People who have a high degree of myopia have a higher chance of having a retinal detachment. This is because myopia is the result of a longer eyeball. The retina can be thought of as a piece of saran wrap. In a normal eye the saran-wrap layer has no holes or thin areas. If you stretch the saran wrap slowly in all directions, some areas thin and develop holes or tears. The same thing in a larger eye - the retina thins in certain places and is more prone to detaching. Boxers and athletes are also more prone to having retinal detachments. Head trauma can shake the retina loose and cause it to tear. People with family histories of retinal detachment are also more prone to having a detachment at some point in their lifetime. The genetic basis of retinal detachment is not well identified in the literature. People who are in car accidents or suffer trauma to the head are also prone to detach, as the force of the head-jerking cause the thin tissue of the retina to tear. Sometimes a sneeze, cough or quickly standing up or bending over can stimulate the retina to detach. These are all examples of Valsalva, where pressure exerted behind the eye (sinuses) pushes forward enough to affect the retina. Retina detachments can be caused by eye rubbing, getting poked in the eye or even having a child hit you in your head or face by accident. Standing on your head or being inverted can cause a detachment, so if you have a family history of retinal detachments or are highly myopic, yoga and other inverted exercises are contra-indicated. Retina detachments have occurred from roller coaster rides, swing-sets or exercise equipment and other motion related events.
Retinal detachments are usually successfully treated if caught within the first 24-48 hours. The retina is nourished by the blood vessels behind it, so if it detaches and is separated from those vessels, the sensitive nerve cells that comprise it slowly die off. Signs of retina detachment include flashes of light like fireworks going off in your side vision. When you try to look towards the flashes, you can't look directly at them because they move in the direction you try to look at. They may or may not be accompanied by floating spots in your vision. Floaters, as they are called, can be anything from the condensing of the vitreous humor within the eye to a total detachment. Some people actually see a wavy line in their vision, half their vision disappear or lose total vision in the eye which detached. If you experience any of these symptoms or think you are experiencing any of these symptoms, see your eye doctor immediately and he/she can rule out whether you had a detachment. Emergency surgery can save your eye, but waiting can cause you to lose most of your vision in the affected eye.
Treatment for retinal detachment sometimes involves tacking the retina back on with a laser. Other tools that can be used include a cryogenic probe that actually can freeze small segments of the retina back in place and hold the whole retina down. Sometimes the eye is pushed toward the detached retina and held in place by a band that is wrapped around the outside of the eyeball within the eye socket. This is known as Scleral Buckling. (a buckle placed around the sclera, or white part of the eye). In most surgeries where the retina is tacked down, a silicone compound or perfluorocarbon compound is used to "weigh down" the unattached retina, helping to hold it (acting as a "tamponade") in place. In other surgeries, the patient is forced to lay face down and an air-bubble is injected into the eye the rising of the air bubble pushes the retina back into place. The patient may have to lie in this position for several weeks.