An Ounce Of Prevention

Detecting macular degeneration early prevents progression, saves vision.

Data from the latest census shows there are 76.4 million baby boomers among the US population. Baby boomers, the second largest generational group in the nation behind millennials, are individuals born between 1946 and 1964. By 2030, all baby boomers will be 65 or older and at risk for age-related disorders, including macular degeneration.

“As our population ages, it is vital for people to know the facts about macular degeneration and understand the importance of early detection,” stresses Ruwan A. Silva, MD, MPhil, a fellowship-trained retina specialist at Florida Retina Institute. “When this disease is caught early, we can often slow its progression and prevent permanent vision loss.

“This is particularly important for baby boomers because macular degeneration is the leading cause of vision loss and blindness in Americans 65 and older.”

Macular degeneration is advanced aging of the retina, the membrane of neurosensory cells located at the back of the eye. The retina detects light and allows people to perceive the world. Macular degeneration primarily affects the retinal pigment epithelium, the thin layer of cells that nourishes the retina, with consequent changes then occurring in the neurosensory retina itself.

“As we get older, this layer of nutritional support also gets older and stops functioning efficiently,” Dr. Silva informs. “When this occurs, we start to lose some of the cells of the neurological portion of the retina, the part that detects light, called the macula. The macula is responsible for our central vision, which enables us to see faces, read and drive. When we start to lose those cells, that is when patients can become symptomatic from macular degeneration.”

Age is an uncontrollable risk factor for macular degeneration. Other uncontrollable risk factors are genetics, being farsighted and being female, because women generally live longer than men. There are other risk factors that are controllable. These include smoking, being overweight and having unchecked cardiovascular disease or high blood pressure.

“Macular degeneration results from an accumulation of damage to the retina over a lifetime,” Dr. Silva observes. “There are several factors believed to be involved. For one, the retina is very metabolically active. Its cells are almost always firing. This constant activity uses a lot of energy and produces a lot of waste, which cumulatively causes damage to the retina and its support system.”

Another factor associated with the development of macular degeneration is extended exposure to light. Just as exposure to light over time damages the skin, a lifetime of looking at light is thought to harm the retina and macula. Long-term exposure to the sun without sunglasses is another controllable risk factor.

“The last factor believed to be relevant is excess exposure to oxygen,” Dr. Silva discloses. “All cells require oxygen to create energy, but oxygen can actually cause damage long-term and in large quantities. The eye has a very large need for oxygen, but extensive exposure over time is believed to be another mechanism of damage to the macula.”

Explaining Dry and Wet

There are two main types of macular degeneration, dry and wet, Dr. Silva reports. The dry type is more common, occurring in about 90 percent of all macular degeneration cases. There are generally no noticeable symptoms associated with dry macular degeneration, so it is typically detected during an eye exam.

“Dry macular degeneration is the advanced aging and long-term damage to the retina and macula I previously described,” Dr. Silva states. “Most afflicted people have this type, in which small, yellowish deposits called drusen form in the macula. Drusen may not initially cause vision changes, but they may dim or distort vision as they get larger and more numerous.”

“There’s good news for people who develop wet macular degeneration.” – Dr. Silva

About 10 percent of people with macular degeneration develop the more advanced wet type. It is called “wet” because it involves the growth of blood vessels in the back of the eye.

“When the retina starts to lose its nutritional layer, it tries to compensate for that by growing new blood vessels,” Dr. Silva explains. “Unfortunately, these blood vessels can cause more harm than good.”

The new blood vessels can become unstable and leak fluid or blood into the macula, causing swelling that distorts vision. Straight lines appear wavy, and people often notice blind spots in their vision or a loss of central vision. Bleeding from the blood vessels may eventually result in the formation of scar tissue, which can cause a permanent loss of central vision.

“But there’s good news for people who develop wet macular degeneration,” Dr. Silva assures. “There’s a treatment that is very effective in preventing further vision loss once those blood vessels begin to form. The treatment is injections of medication that halts the growth of the unstable blood vessels.”

The medications block a protein called vascular endothelial growth factor, or VEGF, which initiates new blood vessel formation. There are three anti-VEGF medications approved for wet macular degeneration treatment: bevacizumab, brand name AVASTIN®, ranibizumab, or LUCENTIS®, and aflibercept, or EYLEA®.

“AVASTIN and LUCENTIS gained approval from the Food and Drug Administration approximately 15 years ago, and EYLEA gained FDA approval about 10 years ago,” Dr. Silva reports. “Before these drugs were introduced, nearly all patients with wet macular degeneration experienced a rapid and severe loss of central vision.

“These medications have been supremely effective. Not only do the blood vessels stop growing, numerous studies show they actually regress. In many cases, patients gain three to four lines of vision, meaning they actually double their visual acuity compared to when they began the injections.”

Slowing Advancement

“If people notice a change in their vision, typically blurriness or distortion, they’ve often already developed wet macular degeneration,” the doctor notes. “There’s no pain or irritation involved. People simply begin to see a smudge of blurriness in their central vision.

“But again, there are things we can do to help prevent progression of this disease. Smoking has a profoundly negative effect on people who have or are developing macular degeneration, so avoiding smoking or quitting if you smoke is critical for slowing progression to the wet form.

“Healthy nutrition and a healthy lifestyle are important as well. It is believed that eating a lot of green, leafy vegetables that are high in antioxidants is also helpful in slowing progression of macular degeneration.”
Taking a specific formulation of eye vitamins is another way to halt the disease.

“These vitamins are shown to be extremely beneficial to people with intermediate and even late-stage macular degeneration by reducing the growth of abnormal blood vessels,” Dr. Silva elaborates. “The specific vitamin formulation recommended, which has been studied for more than 20 years, is available without a prescription.”

© FHCN article by Patti DiPanfilo. Photo courtesy of Florida Retina Institute. mkb

 

Print This Article
    • Florida Retina Institute

      Founded by James A. Staman, MD in 1979, Florida Retina Institute has 19 locations throughout Central Florida, North Florida, and Southeast Georgia. They have proudly delivered Excellence in Vitreo-Retinal Diseases and Surgery for 40 years. T... Read More

    • Ruwan A. Silva, MD, MPhil

      Ruwan A. Silva, MD, MPhil, completed his undergraduate education with highest honors at Harvard University in Cambridge, MA, majoring in neurobiology. He earned a Master of Philosophy degree in neurobiology from Cambridge University in En... Read More