It's no secret that from age 50, most people experience changes in vision, including blurriness and flickering matter.
This deterioration doesn't stop at age 50; as people age, there's a chance of age-related macular degeneration (AMD), cataracts and glaucoma - all diseases that can cause blindness.
Which treatments are available?
Doctors recommend that everyone 50 and over be examined by an ophthalmologist once every two years and once a year from age 65 and up. People in risk groups like smokers or those with hereditary eye problems should be tested at younger ages. One reason for testing is to detect AMD, the main cause of blindness among the elderly in Israel.
What is AMD?
AMD is a neurological disease characterized by vision distortions and is the main cause of blindness among the elderly population in Israel and in all Western countries.
At age 75, signs of the disease can be identified in a third of people in this age group. The disease manifests itself in the weakness of the retina, which is the nerve layer in the back of the eyeball which receives light, which in turn transmits information to the brain and produces images. The retina is also metabolically active, consuming a lot of energy and producing waste products.
In the initial stage of the disease called the "dry stage," there are deposits of small crystals of waste materials called drusen under the center of the retina.
In a normal person, this layer is supposed to clean the waste materials that sink there, but with age and due to other factors, this layer weakens. Another reason for the layer to weaken is genetic predisposition in which one of the enzymes with a certain deficiency or damage from smoking leads to a load of waste that the body needs to clean.
Hereditary background is also a significant risk factor. For example, AMD occurs approximately 2-4 times higher in first degree relatives of patients.
In the initial stage no damage occurs, there's no pain, and there's no visual disturbance, but as the disease progresses two things happen.
The cells of the retina begin to degenerate and small dead spots are formed in the vision, and in the layer below the retina abnormal blood vessels can grow into the retina; these vessels can also bleed and excrete fluids.
This stage is called the "wet stage," and because the retina should be a transparent and thin layer, the accumulation of fluids or blood greatly interferes with vision.
What can be done about AMD and how is it treated?
Today, there's still no drug treatment, but as soon as the dry stage is diagnosed you can take a combination of vitamins to reduce the risk of moving to the next stage.
Statistics show that within five years, 30% of the people with dry macular degeneration will progress to the wet stage. It's necessary to be constantly monitored even if the disease is discovered at an early stage and to maintain a healthy lifestyle, along with normal blood pressure, exercising and avoiding smoking.
What's the treatment for people who have reached the wet stage?
Although the disease doesn't lead to 100% blindness, since it only affects the center of the retina and one can see peripherally, it's a disease of both eyes so the disease can significantly affect vision.
In the past, laser treatment was common, but it also caused damage because aside from the damaged retina, the treatment also damaged the normal retina. Recently, doctors have seen that drugs injected directly into the eye cavity can slow down deterioration because they prevent the growth of abnormal blood vessels and cause fluid and blood to be absorbed. The injections are targeted and preserve and improve vision over the years.
This is an injection of antibodies to the protein VEGF, a growth factor responsible for the development of new blood vessels formed in the eye during the degeneration process.
The protein is found in the body naturally but its amount increases in certain situations in which there is a lack of oxygen or inflammation and is part of the pathology of many vascular diseases, including cancer. Injections block the action of this substance and prevent the development of the new blood vessels.
There are several such injections performed by ophthalmologists today, usually those specializing in the retina. One of the injections is targeted at the disease and relevant to the 20% of second-line patients suffering from the wet phase.
The treatment dries the retina better and there's even an interval between the periods of time required for each injection compared to other injections, which allows patients a much higher quality of life.
The author is the director of Assuta HaShalom Eye Institute and the head of ophthalmology in the Assuta network of medical centers.