Age-related macular degeneration (AMD) is a degenerative process involving the central retina or macular. AMD causes legal blindness in 1.7% of people age 50 or older and is the leading cause for blindness in the USA.
Symptoms of AMD include:
- Loss of central vision
- Blurry central vision
- Wavy central vision
- Distortion in the central vision
There are two types of AMD:
- Dry (non-neovascular)
- Wet (neovascular)
About 85% of patients with AMD have the dry form of AMD, while 15% of patients will develop the wet form of AMD.
Fortunately most patients have dry AMD and they often do very well their entire lives without much central vision loss. Over time, however, about 10% of patients with dry AMD will develop enough degenerative changes in the macula to cause central vision loss or blindness.
In about 15% of patients with dry AMD, the condition eventually turns into wet AMD and that will often result in severe central vision loss. Wet AMD occurs when abnormal new blood vessels begin to grow under the central retina or macula causing bleeding, leaking and exudative changes that will ultimately lead to central macular scarring.
Risk factors for AMD include:
- Family history of AMD (various genes have been associated with the development of AMD)
- Having blue or light colored eyes
- Long-term, unprotected exposure to the sun
Other high possible risk factors would include hypertension (high blood pressure), high cholesterol and a diet high in fat.
What Can Patients Do?
A simple test that can be done by the patient at home is called the Amsler Grid Test. Patients are instructed to test each eye separately and report any distortion, waviness or missing areas in the grid immediately to the doctor.
Age-Related Eye Disease Studies (AREDS/AREDS2). The National Eye Institute conducted the Age-Related Eye Disease Studies and found that patients taking theses nutrition supplements could reduce the risk of progression of AMD.
Aside from a complete eye and retinal examination, there are diagnostic tests that your ophthalmologist can perform to confirm the diagnosis of dry or wet AMD:
- Optical Coherence Tomography (OCT) Scans
- Fluorescein Angiography
- Indocyanine Green Angiography
- OCT – Angiography
Treatments for Dry AMD
AREDS 2 nutritional supplements can reduce the progression of this disease.
Treatments for Wet AMD
Injections of medications (intravitreal injections) into the eye in order stop the abnormal blood vessels from growing under the macula. Various medications are used for the treatment of macular degeneration. These include:
- Kenalog® and Triesence® have been used in patients with wet AMD
Laser photocoagulation techniques such as thermal laser photocoagulation and Visudyne® photodynamic therapy are also useful at times in the treatment of wet AMD.