Much of our daily routine depends on our sense of sight. Deteriorating vision means less freedom and an increased dependence on the people around us. For aging individuals who have lived independently all of their lives, the prospect of going blind is both frightening and frustrating. Although we take it for granted that loss of vision comes hand-in-hand with advancing age, what we are unaware of is that majority of senior citizens lose their vision because of age-related macular degeneration (AMD). This is an eye disease that causes loss of central vision, leaving only peripheral, or side, vision intact. It is the leading cause of blindness for people over 50 in the western world. An estimated 25 to 30 million people worldwide are affected by AMD, and 10 percent of people in their 60s are at risk. The risk increases to 25 percent for individuals aged 75.
Dr. Harvey Uy of the Asian Eye Institute explains that there are two common forms of AMD: dry and wet. Dry AMD is identified by the collection of yellow, fatty deposits called drusen in the macula, the central part of the retina responsible for detailed central vision, while wet AMD is characterized by abnormal, leaky blood vessels in the macula. Although wet AMD is less common and accounts for 10-15 percent of all AMD cases, the chance for severe sight loss is greater.
Fortunately, a new medication to arrest the onset of blindness from AMD in older people is now available. This gives hope for a continued productive and self-reliant lifestyle. A drug called Ranibizumab, manufactured by Novartis Opthalmics, is the first and only drug shown in clinical trials to improve vision and give vision-related quality of life in a significant number of people suffering from AMD.
“For the first time, you could reverse the visual loss; you can return some of the patient’s vision,” says Dr. Uy.
An average of four to five injections results in improved sight for patients. “It is a breakthrough drug because when a patient had the disease in the past, we could not tell him that we can give him better vision. It was usually a downhill ride to blindness. Now, there is better hope,” Uy asserts.
Ninety percent of patients given Ranibizumab reported maintained or improved vision. Still, early detection of AMD is crucial because lost vision cannot be fully regained. And thus, eye care specialists recommend that medical eye exams should be undertaken regularly.
“People have two eyes so when one eye is still good, they don’t go to the doctor. It is only when both eyes are bad that they have checkups,” rues Dr. Uy.
Symptoms of AMD include distortion of images and lines (metamorphosia), blurring and reduced visual acuity, decreased color vision, increased glare sensitivity resulting from sensitivity to changing light conditions, and the development of scotoma or a dark spot in the center of a visual field surrounded by a distorted image. Apart from age, the risk of blindness is increased by exposure to harmful light or radiation, smoking, and health conditions such as hypertension, high cholesterol levels, and diabetes. Genetic predisposition may determine why some people are more likely than others to have AMD. Lighter-skinned people and women are also more prone to the disease. Although aging is the biggest risk factor for AMD and cannot be forestalled, Dr. Uy stresses that overall health-consciousness reduces the risk of blindness. A healthy diet and lifestyle will prevent or control hypertension, diabetes, and high cholesterol levels that can damage blood vessels in the eyes. Likewise, the intake of antioxidants will also remove toxic substances or free radicals in the body. Just as importantly, regular eye checkups, especially after age 50, will lead to early detection and treatment of age-related macular degeneration.
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Dr. Harvey Uy can be reached at the Asian Eye Institute, 9th and 10th floors, Phinma Plaza, Rockwell Center, Makati City Philippines, telephone numbers 898-2011 to 20 and website www.asianeyeinstitute.com.