A common complaint of those 65 and older, age-related macular degeneration (ARMD or AMD) is responsible for most of the vision loss and blindness in older Americans. Since the senior population is increasing in this country, macular degeneration is becoming a greater and greater problem. It typically causes a slow loss of vision not accompanied by pain, but may come on suddenly. Early warning signs of AMD include very distorted vision or shadowy areas in the central line of vision.
Macular degeneration is essentially a breakdown of the area of the retina that controls the sharper, central vision required for activities such as reading or driving. AMD can cause central vision loss.
AMD can be classified as either neovascular (wet) or non-neovascular (dry). The term neovascular describes the development of blood vessels in places where they are not meant to grow.
Dry macular degeneration is an early form of AMD which doctors believe results from the thinning and aging of macular tissues, the accumulation of pigment deposits on the macula, or both. With dry AMD, yellowish spots, called drusen, appear around the macula, likely created by deteriorating tissue. While gradual loss of central vision may occur with the dry form, it is markedly less severe than that which occurs with wet AMD. On the other hand, dry AMD can develop into a condition called geographic atrophy, or GA, whereby the slow deprivation of cells in the retina leads to severe loss of vision. There are no current FDA-approved treatments for dry AMD; however, clinical trials are underway.
In a very few cases, dry AMD develops into the more serious wet AMD. With wet AMD, new blood vessels begin to grow underneath the retina, leaking blood and fluid. The leaking blood vessels ultimately kill the sensitive retinal cells, creating blind spots in the person’s central vision. Wet AMD can be “classic” or “occult”. There are several FDA-approved medications for the treatment of wet macular degeneration, including Macugen, Lucentis, and Visudyne. Visudyne is prescribed with Photodynamic Therapy. Lucentis has been proven effective in improving the vision of a large number of patients suffering from wet AMD.
The high blood sugar levels associated with diabetes can cause blood vessels in the retina to swell and leak, a condition called Diabetic Retinopathy. Anyone who has been diagnosed as diabetic is at risk for the condition. Early on, there may be no noticeable change in vision, but as diabetic retinopathy progresses, it can seriously threaten a person’s sight.
Diabetic retinopathy may present symptoms such as “floaters.” Patients may also experience difficulty reading or doing close-up work as fluid collecting in the macula obstructs the most sensitive area of the retina. The accumulation of fluid in the macula is known as macular edema.
Patients with diabetic retinopathy may also experience double vision, which takes place when the condition begins to affect the surrounding eye muscles. A person experiencing one or more of these signs should consult an eye professional right away.
Luckily, most diabetics can greatly reduce their chances of developing diabetic retinopathy by properly managing their blood sugar, maintaining a healthy diet, getting regular exercise, checking blood pressure levels, and adhering to their doctor’s recommendations.
The American Academy of Ophthalmology estimates that as many as 95% of diabetics with diabetic retinopathy can avoid significant loss of vision if they receive prompt treatment. Early detection is key, which is why diabetic patients are encouraged to schedule a dilated eye exam annually, or more often.
Retinal Tears and Retinal Holes
Retinal tears, also called retinal holes, can be a serious eye condition. As we age, the vitreous gel in the eye begins to change. Sometimes it sticks to and pulls away at the retina, which can cause the retina to tear. Retinal tears can be asymptomatic or may produce flashes or floaters in the field of vision.
If vitreous fluid pours through the tear, it can pool into the space between the retina and eye wall and cause retinal detachment. Symptoms of retinal detachment are wavy or watery vision, a curtain across the field of vision, or distorted/reduced central vision.
Retinal detachment can lead to blindness and is considered an ophthalmologic emergency.
Retinal Vein Occlusion
Retinal vein occlusion is a type of retinal vascular disease that causes vision loss. It is common in middle-aged and older people.
Retinal occlusion occurs when an artery or vein serving the retina becomes blocked. If the blockage occurs in an artery, the part of the retina that is not being nourished will die, causing blindness in that area. This is an emergency.
Unfortunately, there are no proven effective treatments for occlusion of a retinal artery. Techniques include reducing the pressure in the eye, medication, carbogen therapy, thrombolytics, and hyperbaric oxygen therapy.
If the blockage is in a vein, it may spill blood and fluid into the eye, causing temporary blurring and clouding of vision until the fluid is re-absorbed by the body. No treatment is needed unless blood vessel overgrowth occurs, which can be treated with lasers.
Blood vessel overgrowth left untreated can lead to retinal detachment or glaucoma.