While vision problems often herald old age, sometimes they signal a more serious disorder that can occur at any age, namely detachment of the retina.
The retina lines the inner face of the back of the eyeball and contains light-sensitive cells that transmit images to the brain. "When the retina separates from the back of the eye, vision is impaired," says Dr. Steve Russell, associate professor and director of vitreoretinal services in the University of Iowa Department of Ophthalmology and Visual Sciences.
Retina detachment can happen at any age, but it primarily occurs in middle-aged and elderly people. Those who have had surgery to remove cataracts are the most susceptible, Russell says. Also, if someone in your family has had a detached retina, you are at an increased risk of developing the condition.
Retinal detachment cannot be seen from the outside of the eye. In addition, it does not cause any pain or discomfort. Some symptoms are flashes of light--the common sensation of "seeing lightning"--and floaters, small specks that appear in our field of vision. Another sign may be loss of part of your field of vision or side vision. This is best detected by covering your unaffected eye. Being aware of any changes in your vision and seeking treatment immediately can help prevent serious retinal damage. Early detection is the best way to avoid vision impairment or loss, Russell says.
Of the three kinds of retinal detachments, only one is caused by holes or tears on the retina. These are the type that may require urgent attention, Russell says. Changes in the vitreous gel in the eye also can play a role in the development of retinal detachments. The vitreous gel, which is firmly attached to the retina in a healthy eye, may shrink over time, pulling away from the retina. Areas where the vitreous gel strongly adheres to the retina are pulled from the rest of the retina, which may make a hole or tear. They also may develop after the eye is injured, such as by a severe blow or cut.
"Fluid gets through the tear or hole and causes the remainder of the retina to elevate or detach," Russell explains.
Those with severe nearsightedness are more prone to developing retinal tears, holes or detachments. The eye gets larger with nearsightedness, stretching the vitreous gel and causing it to pull away from the retina. A second form of retinal detachment may develop when new blood vessels grow on the surface of the retina. This is especially common in diabetic patients with severe eye disease.
There are several ways to repair a detached retina. One method involves indenting the eye wall from the outside of the globe with a silicone band. The band pushes the eye wall toward the hole or tear, closing the hole and allowing scar tissue to form and seal the edges, Russell explains.
Another treatment is to inject a gas bubble inside the eye, which pushes the hole closed from the inside. A vitrectomy may be done to remove the shrunken vitreous gel that is pulling on the retina.
Other times, laser surgery may be helpful if the retinal detachment is limited in size. The laser seals the holes or tears, forming scar tissue. Cryopexy, or freezing the tissue around the tear or hole also stimulates scar tissue growth, he says.
Secondary detachments are caused by tumors or diseases. They can be controlled only by treating the disease itself.
University of Iowa Health Science Relations and Steve Russell