- The author of this article is Dr Rajani Battu, Co-Founder and Chief Medical Officer, Eyestem
One of my patients, Mr Arvind Kumar(name changed), aged 84 years, came in for a consult since he found it increasingly difficult to read the newspaper with his present glasses. He had undergone cataract surgery about ten years ago and was hoping a change in his glasses would correct his vision. Unfortunately, he had a progressive weakening in his retina, the nerve of the eye, causing his vision difficulties. He had a condition called Age-Related Macular Degeneration (AMD), a disease affecting the eye’s nerve called the retina.
The central part of the retina is called the macula, which can start becoming weaker as a person grows older. One of the important layers of the retina is called the retinal pigment epithelium (RPE). AMD is caused by progressive damage to the RPE at the macula.
AMD is the most common cause of blindness in people older than 60 years worldwide. About 15 -25 million people (1.82-2.25%) in India suffer from AMD.
AMD can be of two types – dry and wet AMD. Most patients with AMD (about 85%) have the dry form. This is caused by deposits called ‘drusen’ formed under the retina. Some patients with advanced forms of dry AMD develop a ‘Geographic Atrophy’. Some patients with dry form can progress into the second form of the disease, called wet AMD.
People affected with AMD may notice difficulty reading smaller print, which cannot be corrected with glasses or cataract surgery. This can progressively lead to severe difficulty in reading and writing and an inability to drive. Some people may also notice distortion of their central vision, which may signify wet AMD. AMD can have a profound impact on quality of life and independence. Advanced dry AMD can lead to legal blindness. However, it is important to note that most people retain good peripheral vision, which allows them to be mobile reasonably.
Wet AMD is the more severe form of AMD and is treated by injections of anti-VEGF agents (Ranibizumab, Bevacizumab, Aflibercept, Brolucizumab) into the cavity (vitreous) of the eye. These are done as daycare procedures in India. Most people with wet AMD require multiple injections. Currently, there is no definitive treatment available for dry AMD in the world. However, oral antioxidant/mineral supplementation has been recommended to slow the progression of the disease.
While there is no definitive treatment to halt the progression of dry AMD, there has been remarkable scientific progress over the last few years, making a cure likely in the medium term. Replacing the lost cells via stem cell therapy is one such promising treatment. Many companies are working on replacing the RPE cells via surgical procedures to achieve this. Others are trying to address the genetic changes underlying AMD with gene therapy.
If you have advanced AMD, low visual aids help significantly in reading and writing; your eye doctor should be able to help with this. Have antioxidant rich foods and maintain a healthy lifestyle. Protect your eyes from sun exposure. It is very important to stop smoking. Please also consult your retina specialist regularly.