by Dr. Bill Blank, MD
© Copyright 2022. All rights reserved!
Published in Midwest Flyer Magazine April/May 2022 online issue
Age-Related Macular Degeneration (ARMD) is a major cause of visual loss. It affects approximately 11 million Americans. Its incidence gradually increases with age to 12% in people 80 and older. The macula is the central 2% of the retina. Whenever we look directly at something, we are using our macula. It gives us sharp, central vison for fine detail, color, and contrast. We need a healthy macula to be able to read. ARMD only affects central vision. Peripheral, or side vision is preserved. People with severe ARMD can be legally blind, but will be able to function at a reduced level because their peripheral vision is normal. They will never progress to being unable to detect light.
There are 2 forms of ARMD, dry and wet. The dry is much more common, 90% of the cases. The dry form leads to a slow deterioration of the retinal cells, the cones, of the macula with a gradual deterioration of central vision. The wet form is caused by the growth of tiny new blood vessels (neovascularization) into the macula from behind. These blood vessels tend to leak fluid and blood into the macula, leading to serious distortion and loss of central vision. This growth can occur quickly.
Symptoms of ARMD are related to the functions performed by the macula. They include blurred vision, central vision impairment, visual distortion, poor vision in low light, loss of contrast sensitivity and alterations in color vision perception. Progression can be slow and insidious with the dry form and quite rapid, a few hours to a few days, with the wet form. Risk factors include age, heredity, SMOKING, high blood pressure, hardening of the arteries and obesity. Exposure to ultraviolet light may also be a factor. You can see by looking through this list what you can do to decrease your likelihood of developing ARMD or decreasing its severity.
What treatments are available? Dry ARMD is essentially a result of aging. We are trying to slow down aging. Several years ago, the National Eye Institute did two studies called AREDS 1 and 2 for Age Related Eye Disease Studies. The purpose was to determine if preventative treatment with various antioxidant vitamins, minerals, and dietary supplements would be helpful. The studies showed that under limited circumstances, these supplements slowed progression to severe disease in some cases. These supplements are available over the counter under the names AREDS 1 and AREDS 2. AREDS 2 is for smokers. They should not take AREDS 1. The FAA permits these supplements.
Wet ARMD is thought to be caused by something called Vascular Endothelial Growth Factor (VEGF). The goal is to inactivate it. This is done with intraocular (inside of the eye) injections into the vitreous of anti-VEGF medications and steroids. This is done as an outpatient. The frequency of injections depends upon the response. They are particularly helpful in stabilizing the condition.
Will the FAA certify anyone with ARMD? Yes, sometimes. An AME must defer anyone with significant dry or wet ARMD. The FAA will require a Special Issuance for anyone whose ARMD is beyond the early, mild stage. A complete ophthalmological exam will be required. Specific tests will be needed. Intraocular (intra vitreal) injections are approved. There is a 24-hour no fly period after the injection. With close monitoring, these injections have permitted pilots to continue to fly in spite of the disease and enjoy useful vision. In all cases, the airman must meet the visual standards for the class of medical certificate desired. 20/40 for distance and near, best corrected, or uncorrected in each eye is required for Third Class. First and Second Class need 20/20 for distance and 20/40 for near and sometimes for intermediate distances. Again, this apples to each eye. The frequency of follow-up for continued Special Issuance depends upon the individual case. I hope that none of you develop ARMD, but if so, there is hope.
Happy flying!
EDITOR’S NOTE: Columnist William A. Blank is a physician in La Crosse, Wisconsin, and has been an Aviation Medical Examiner (AME) since 1978, and a Senior AME since 1985. Dr. Blank is a retired Ophthalmologist, but still gives some of the ophthalmology lectures at AME renewal seminars. Flying-wise, Dr. Blank holds an Airline Transport Pilot Certificate and has 5600 hours. He is a Certified Instrument Flight Instructor (CFII) and has given over 1200 hours of aerobatic instruction. In addition, Dr. Blank was an airshow performer through the 2014 season and has held a Statement of Aerobatic Competency (SAC) since 1987.
DISCLAIMER: The information contained in this column is the expressed opinion of the author only, and readers are advised to seek the advice of others and refer to the Federal Aviation Regulations and FAA Aeronautical Information Manual for additional information and clarification.
