The retina is the light-sensitive membrane that covers the back of the eyeball. The retina contains photoreceptors, called rods and cones. These convert the light received into nerve impulses carried from the retina to the brain, where the vision is interpreted. The retina can become detached from the eyeball and can cause flecks in the vision, light flashes or the appearance of a curtain over your vision. A detached retina, which can be caused by a variety of factors, can lead to blindness.
Trauma
Because the exact mechanism of action of a retinal detachment is not understood, the role that trauma plays in causing a detachment is vague. It is known, however, that direct trauma to the eye, such as a blow by a baseball bat, fist or stone, can cause the retina to detach. Indirect trauma, such as a blow to the head or body, can also result in the retina detaching. In a study conducted by Arnold Knapp, M.D., the relationship between indirect trauma and retinal detachment was found to be due to the movement of the vitreous, the fluid in the eye. If trauma results in movement, especially whirling or rotating, of the contents of the eye, retinal detachment can occur.
Diabetes
The American Diabetes Association reported in 2007 that 7.8 percent of the population in the United States has diabetes. Diabetes is a disease characterized by an increase in glucose, or sugar, in the blood. Having a high level of sugar in the blood can cause detrimental effects on the body, especially the eyes.
Chronic hyperglycemia (high blood sugar) damages small blood vessels, inhibiting oxygen and nutrients from reaching tissues. The retina is full of tiny blood vessels that can be damaged by the sugar in the blood, causing them to swell or become weak. The weakened vessels may break easily. Over time, scar tissue can form, pulling the retina away from the eye, resulting in a detached retina.
Inflammatory Disorders
Inflammatory disorders can damage the retina and result in retinal detachment. Sarcoidosis is an inflammatory condition of unknown cause that affects many organs. When a patient 's immune system triggers an inflammatory response in sarcoidosis, it does not subside once the harmful substance has been destroyed. This causes immune cells to cluster together into lumps, known as granulomas, in various organs. When this occurs in the eye, the granulomas can cause the retina to detach.
Another inflammatory disorder that can result in retinal detachment is cytomegalovirus (CMV) retinitis. CMV retinitis is an infection of the retina caused by a virus similar to the herpes virus. The infection, if left untreated, can destroy the retina, lead to detachment and result in blindness.
