Symptoms of Age Related Macular Degeneration

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Symptoms of Age Related Macular Degeneration WHAT IS MACULAR DEGENERATION? wavy or crooked, visual distortions, doorway and the choroid are interrupted causing waste or street signs seem bowed, or objects may deposits to form. Lacking proper nutrients, the light- Age related macular degeneration (AMD) is appear smaller or farther away than they sensitive cells of the macula become damaged. a disease that may either suddenly or gradually should, decrease in or loss of central vision, and The damaged cells can no longer send normal destroy the macula’s ability to maintain sharp, a central blurry spot. signals from the macula through the optic nerve to central vision. Interestingly, one’s peripheral or DRY: Progression with dry AMD is typically slower your brain, and consequently your vision becomes side vision remains unaffected. AMD is the leading de-gradation of central vision: need for increasingly blurred cause of “legal blindness” in the United States for bright illumination for reading or near work, diffi culty In either form of AMD, your vision may remain fi ne persons over 65 years of age. AMD is present in adapting to low levels of illumination, worsening blur in one eye up to several years even while the other approximately 10 percent of the population over of printed words, decreased intensity or brightness of eye’s vision has degraded. Most patients don’t the age of 52 and in up to 33 percent of individuals colors, diffi culty recognizing faces, gradual increase realize that one eye’s vision has been severely older than 75. The macula allows alone gives us the in the haziness of overall vision, and a profound drop reduced because your brain compensates the bad ability to have: sharp vision, clear vision, color vision, in your central vision acuity. eye. Once both eyes become involved, life may central vision, and daytime vision. dramatically be affected. WET: Found in approximately 20% of AMD patients. WHAT CAUSES AGE RELATED MACULAR Wet AMD occurs when abnormal retinal blood vessels DEGENERATION? RISK FACTORS: start to grow beneath the macula. These new blood Researchers don’t know the exact causes of vessels are very fragile and The macula, located at macular degeneration, but they have identifi ed consequently leak blood the very back of your eye, some contributing factors. The greatest risk factor is and fl uid. The leaked blood must be healthy to have age. Although AMD may occur during middle age, and fl uid raise the macula normal quality central studies show that people over age 60 are clearly from its normal place at the vision acuity. The macula at greater risk than other age groups. Other risk back of the eye causing is made up of densely factors include: rapid macular damage packed light-sensitive cells Age: In the United States, macular degeneration and a loss of central vision. called cones and rods. is the leading cause of severe vision loss in people Wet AMD is also known as These cells, particularly age 60 and older. advanced AMD and it does the cones, are essential Family History: If someone in your family had not have stages such as dry for central vision. The macular degeneration, your odds of developing AMD. choroid, an underlying macular degeneration are higher. In recent years, DRY: Dry AMD occurs in layer containing blood researchers have identifi ed some of the genes about 80% of patients and vessels sits posterior to a associated with macular degeneration. In the its development is related thin layer of tissue forming future, genetic screening tests may be helpful for to the light-sensitive cells the outermost surface of assessing early risk of the disease. slowly breaking down in the the retina known as the Race: Macular degeneration is more common in macula, gradually blurring retinal pigment epithelium whites than it is in other groups, especially after age central vision. As dry AMD (RPE). The RPE is a critical 75. progresses, you may see a passageway for nutrients Sex: Women are more likely than men are to blurred spot in the center of from the choroid to the develop macular degeneration, and because your vision. With advanced retina and helps remove they tend to live longer, women are more likely to dry AMD, less and less waste products from the experience the effects of severe vision loss from the of the macula functions retina to the choroid. disease. properly and central vision As we grow into Cigarette smoking: If you smoke, stop. Exposure is gradually lost. our latter years, the RPE may deteriorate to cigarette smoke doubles your risk of macular SYMPTOMS OF AGE and lose pigment and degeneration. Cigarette smoking is the single most RELATED MACULAR DEGENERATION: eventually thin (atrophy). This thinning causes a preventable cause of macular degeneration. series of events to occur. Primarily, the nutritional Obesity: Being severely overweight increases WET: The following symptoms may appear and waste-removing cycles between the retina the chance that early or intermediate macular and progress rapidly: Straight lines appearing degeneration will progress to the more severe form TREATMENT OPTIONS: of the disease. Light-colored eyes: People with light-colored Wet AMD can be treated with laser surgery, eyes appear to be at greater risk than do those with photodynamic therapy, and injections with cutting- darker eyes. edge products (anti-VEGF therapy) into the eye. Sunlight Exposure: The retina is more sensitive to Examples of injection therapy are Macugen, shorter wavelengths of light, including ultraviolet Lucentis, and Avastin. Unfortunately, none of these (UV) light, only a small percentage of ultraviolet light treatments are a complete cure for wet AMD. The actually reaches the retina. Most ultraviolet light is disease and loss of vision may progress despite fi ltered by the transparent outer surface of your eye timely and appropriate treatment. (cornea) and the natural crystalline lens in your eye. Current dry AMD treatment cannot reverse dry It’s possible that long-term exposure to ultraviolet macular degeneration. This doesn’t necessarily MACULAR light may increase your risk of developing macular mean you’ll lose all of your sight. Fortunately, dry degeneration, but this risk has not been proved and macular degeneration generally progresses slowly, DEGENERATION remains controversial. and many people live with this condition relatively Low Nutrient levels: This includes low blood levels normally, having productive lives, especially if of minerals, link zinc, and antioxidant vitamins, only one eye is affected. One treatment strategy such as A, C and E. Antioxidants may protect your focuses on anti-oxidant therapy. It was found by cells from oxygen damage (oxidation), which may the National Eye Institute that taking a specifi c partially be responsible for the effects of aging and high-dose formulation of antioxidants and zinc for the development of certain diseases such as signifi cantly reduces the risk of advanced AMD and macular degeneration. its associated vision loss. Slowing AMD’s progression Cardiovascular: These diseases include high from the intermediate stage to the advanced stage blood pressure, stroke, heart attack and coronary will save the vision of many people. artery disease with chest pain (angina). Additional therapies on the horizon for AMD are the use of Kenalog injections, Rheophoresis HOW IS AMD DIAGNOSED? transfusions and even implantable optical devices. To look for signs of the disease, your doctor will use RESOURCES: eye drops to dilate your pupils to obtain a better view of the macula in the back of your eye. AMD http://www.amd.org/site/PageServer http://www.nei.nih.gov/health/maculardegen/armd_facts.asp may be detected during a comprehensive eye http://www.macular.org/ exam that includes a visual acuity test to measure http://www.blindness.org/MacularDegeneration/ http://www.macular-degeneration.org/ how well you see and when the pupils are dilated, BARKER CYPRESS the doctor will use a special lens to examine the retina, optic nerve, and macula for signs of AMD. An Amsler Grid (see picture below) tracks changes within the macula. The pattern of the grid resembles a checkerboard. Any distortions, missing squares, or if the pattern appears wavy this may indicate a macular issue like BARKER CYPRESS AMD. 12320 Barker Cypress, Ste. 400 Cypress, TX 77429 (281) 373-1020 www.eyetrendsbc.com.
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