Age-related macular degeneration (ARMD) is the leading cause of blindness in Americans over the age of 60. It actually affects almost one third of people over 75 years of age. Two hundred thousand Americans develop a severe form of ARMD every year.
ARMD is characterized by damage to the macula, the central portion of the retina. This area, that is rich in cone cells, is responsible for your sharpest form and colour vision. There are two main types of ARMD, “wet” and “dry.” Dry ARMD is far more common, accounting for 90% of ARMD cases. It usually develops very slowly, but can progress to the more severe wet form of the disease. While wet ARMD accounts for only 10% of ARMD cases, it is responsible for 90% of the cases of severe visual loss. Wet ARMD is heralded by the development of abnormal blood vessels that grow under the retinal. These abnormal vessels leak fluid, bleed and eventually create a damaging scar that causes irreversible visual loss.
Early symptoms of ARMD may be minimal. Often, patients notice blurred vision, and waviness and distortion of straight lines. As the disease progresses, the loss of central vision becomes more severe. Dense blind spots often develop, and many routine daily activities such as driving, reading or watching TV become difficult if not impossible.
While we aren’t sure what causes ARMD, there are a number of factors that may increase one’s risk for developing the disease. These factors include smoking, diet, light exposure and other co-morbidities (hypertension and elevated cholesterol). Genetics is also very important, with first-degree relatives of patients with wet ARMD are three times more likely to develop ARMD than controls.
Treatment of ARMD had been particularly frustrating for both patients and ophthalmologists in the past. However, a number of therapies have been approved to treat the wet form of the disease (Visudyne, Macugen). The newest treatment, recently approved by the FDA is a medication called Lucentis, which not only arrested the disease but in a significant number of patients actually improved their vision.
Aside from performing a thorough dilated retinal evaluation to look for ARMD, Dr. Filer also uses Optical Coherence Tomography to help detect wet and dry ARMD at the earliest stages possible. Early detection and prompt treatment may help prevent the damaging effects and visual loss associated with this disease.