How is Geographic Atrophy Diagnosed?
Geographic atrophy is an advanced form of age-related macular degeneration. More than 5 million people worldwide have been diagnosed with geographic atrophy with 1 in 29 people over the age of 75 having geographic atrophy, increasing from 1 in 4 people with geographic atrophy over the age of 90. Age-related macular degeneration can lead to progressive and even permanent vision loss. Commonly referred to as AMD, age-related macular degeneration is a disease that affects the back part of the eye called the macula. The macula is the central part of the retina responsible for the clearest and sharpest part of your vision, most of your color vision, your central vision, and for the fine details of what you see. The macula contains a high concentration of photoreceptor cells that detect light to signal the brain of the images you see.
Risks for geographic atrophy include family history of AMD, genetics, age, race, light colored eyes, smoking, heart disease, diabetes, high blood pressure, high cholesterol and poor diet. Often by the time symptoms are noticed, geographic atrophy may have already progressed to both eyes. Some vision changing signs and symptoms include difficulty seeing within your central vision. Numbers or letters disappearing or missing when reading, dark spots in central vision, difficulty seeing in dim light, dull or washed-out colors in vision, and vision that is not as sharp or clear.
How is geographic atrophy diagnosed? As always, the best course of treatment for vision is to visit with a board-certified ophthalmologist who will provide a comprehensive eye exam. During the eye exam, a visual acuity test and a dilated eye examination will generally be administered first. A visual acuity test will determine how well a patient can see through the central vision of each eye usually through a series of reading eye charts. Wen the eyes are dilated, the pupils widen so that the doctor can have a better view if the back of the eye, specifically looking at the retina and the macula for any signs of change. If you eye doctor suspects changes to the macula or any other factors, the following tests will be conducted for diagnosis: Fundus photograph, optical coherence tomography (OCT), fluorescein angiography, and visual function tests (additional tests to help assess any visual impairment). The fundus photograph uses a specialized microscope attached a camera to take a picture of the retina, including blood vessels and the optic nerve. This test is non-invasive and only takes a minute or two to capture an image of the interior surface of the eye. An OCT test provides a cross sectional image of the eye to show the doctor is the macula has thickened, lost any tissue, or if there is a build-up of fluid under the retina that may be affecting vision. Fluorescein angiography involves injecting a special dye into the vein in a patient’s arm to best view and record the flood flow in the retina and choroid. In under 15 seconds, the dye reaches the blood vessel in the eye causing them to fluoresce or shine brightly for the ophthalmologist to locate any problems and where to focus on treatment.
Although there are currently no treatment options available for those affected by geographic atrophy, Retina Consultants of Nevada can help you with rehabilitation resources that can improve your quality of life with low vision. Continued eye exams are currently the most proactive way to monitor any progression of geographic atrophy. To learn more, contact Retina Consultants of Nevada at 702-369-0200 or online at WEBSITE.