Age-related macular degeneration is the leading cause of blindness in the United States and many European countries. The neovascular "wet" form of the disease is responsible for most (90%) severe loss of vision. There are approximately 200,000 new cases of wet macular degeneration in the United States each year.
The average age of patients with the wet form of macular degeneration is the mid-70s. It rarely occurs before the age of 50. Wet macular degeneration is more common in whites, but occurs in all races.
The wet form of macular degeneration is usually associated with aging, but other diseases which can cause wet macular degeneration include high myopia (being very nearsighted) and some intraocular infections like histoplasmosis.
The first proven treatment was laser photocoagulation, but only 10-15% of eyes with wet macular degeneration are treatable with laser. Then recurrences after laser treatment are common (70% in 5 years). The average visual acuity 3 years after treatment is usually 20/200 to 20/250.
Patients rarely lose all of their vision from macular degeneration. Though they have poor central vision, most can walk around, dress themselves, and perform many of their normal daily tasks.
Social and Economic Implications of Age-related Macular Degeneration
Since ARMD results in loss or impaired central vision, it is not surprising that the majority of patients either become partially sighted or legally blind. Activities which require good central vision such as reading, writing and carrying out certain domestic tasks are all affected.
Many macular degeneration patients require help to perform activities of daily living. Sometimes, their visual handicap necessitates admission to a nursing home. The social cost of this handicap is enormous in both personal and social terms. When both eyes are affected, patients experience serious loss of quality of life and independence.
What makes macular degeneration research even more important is that recent evidence suggests that macular degeneration is now a more common cause of permanent visual loss than diabetes.
How Do We Solve This Problem?
In recent decades we have witnessed improved technology offering solutions for patients suffering from cataract, diabetic retinopathy, and glaucoma. We have also seen the aging of our patient population. Since the number of patients suffering from blindness due to treatable conditions has fallen dramatically, age-related macular degeneration has become the most pressing "vision-related" public health dilemma in the developed world.
Age Related Macular Degeneration (ARMD) is disease of the eyes that is the number one cause of permanent vision loss among about 15 million Americans greater than 60 years of age. As the name suggests, ARMD is an age related disease that becomes more prevalent and may get worse as a person gets older. It is important to understand that unless some other form of eye condition develops, patients never go completely blind with macula degeneration.
The macula is the bull's eye center of the retina (the inside lining of the back of the eye) and it has the highest density of cells for detail seeing such as reading books or letters. Unfortunately for some people, these tiny cells deteriorate over time.
There are two basic types of ARMD. There is the "dry" and the "wet" forms. Ninety percent of ARMD is the "dry" form, which means that there are no hemorrhages or bleeding in the macula. The "wet" form does have the hemorrhages and accounts for about 10% of the cases of ARMD.
Often the first signs of ARMD are not noticed by those who have the start of the disease though the eye doctor can usually detect it by examination of the insides parts of the eye. The first signs to patients could be noticing difficulty adjusting to different lighting conditions such as driving at night, coming in from the bright sunlight to a dim lit area, or leaving the dim room and entering the bright sunlight. If ARMD is present, a person may experience long lags of dim vision before vision recovery.
The natural progress of ARMD usually yields a gradual vague central vision blur which makes ordinary visual task challenging. Occasionally, these changes in vision can occur rapidly. Vision of the ARMD patients may also seem to fluctuate from day to day.
Risk factors for getting ARMD include smoking, high blood pressure, exposure to the sun's harmful light rays called UV light, improper diet, age, Caucasian race with blue eyes and family history of ARMD.
There is no cure for ARMD. Eye doctors typically focus our therapy for ARMD patients in four main categories, which include prevention, surgical lasers, rehabilitation, and now as of January 2005 a new medical treatment with the drug called MACUGEN.
Prevention includes smoking cessasasion as soon as possible, reduction of harmful ultra violet light rays, blood pressure control and proper diet and exercise. Special antioxidant vitamins for non-smokers and even a new vitamin especially designed for the smoker who will not quit can be recommended by an eye care professional. Consider asking the eye care professionals for more specific about each of these new prevention solutions.
Photodynamic Therapy (PDT) surgical technique that uses a special cold laser that activates VISUDYNE that is injected IV that causes the abnormal bleeding blood vessels in the macula to shrink. Only the "wet" forms of ARMD may respond to this relatively new surgical technique.
Rehabilitation includes Low Vision optical devices that can be specifically fit and designed for each individual ARMD patient's needs. A Low Vision Specialist is needed to diagnose which low vision device is best suited to each patient.
Medical treatment is now available in 2005, as the FDA has approved the first drug for the treatment of "wet" ARMD. This is an exciting new breakthrough in the medical treatment of "wet" ARMD in that it has been proven to reduce the mechanism that produces the abnormal blood vessel that burst and lead to the loss of vision.
It would be reasonable to assume that a combination of PDT and Macugen may be the best way to treat the bleeding that causes the damage to the macula in ARMD.
Also, there are numerous experimental treatments that are currently being investigated that may prove to be helpful in the treatment or prevention of macular degeneration. Only through established scientific study protocols may these experimental therapies prove to be the best choice for treatment in the future.
It is very important for patients who have all types of ARMD to be examined routinely for changes in the macula that may respond to new or established forms of treatments. Through the continuous efforts of doctors and patients alike, we can hopefully manage the effects of ARMD.
Kirk D. Kvitle, O.D.