About macular degeneration
What is macular degeneration?
Macular degeneration facts
- The macula is in the center of the retina, the light-sensitive layer of tissue at the back of the eye. The macula is responsible for central vision (straight-ahead vision). Degeneration of the macula occurs most often after the age of 60 years and is termed age-related macular generation (AMD).
- AMD is a painless condition.
- There are two types of AMD: dry AMD and wet AMD.
- Smoking, high blood pressure, obesity, a diet high in unsaturated fats and simple carbohydrates and lack of exercise all increase the risk of AMD.
- Early symptoms of dry AMD include slightly blurred vision, the need for more light for reading, and difficulty recognizing faces until very close to the person. A symptom of more advanced dry AMD is the presence of a blurred spot in the center of vision. An early symptom of wet AMD is the wavy appearance of straight lines.
- Dry AMD cannot be treated at present, but progression can be slowed through a healthy lifestyle and, in certain cases, through anti-oxidant vitamins. Injections into the eye of anti-angiogenic agents are successfully used in arresting or slowing wet AMD. Because of new therapies for the wet form of AMD, early diagnosis of wet AMD is particularly critical.
What is macular degeneration?
Macular degeneration is a common, painless eye condition in which the central portion of the retina deteriorates and does not function adequately.
What is the retina?
The retina is the light sensitive tissue located in the back of the eye. It is like the film in a camera, recording the images we see and sending them via the optic nerve from the eye to the brain. The retina instantly converts light images into electrical impulses through a chemical reaction. The retina then sends these impulses or signal, to the brain, where we interpret what we see, process the visual information, and relate what we see to the rest of our environment.
What is the macula?
The macula is a small portion of the retina located in the central portion of the retina. The macula is responsible for central vision (straight-ahead vision) and provides the ability to see fine detail in your direct line of sight. We use the macula of each eye to have the clear vision that allows us to read, drive a car, and recognize faces or colors. The non-macular areas of the retina provide us with our side vision and best night vision.
What is age-related macular degeneration (AMD)?
Although there are many types of macular degeneration, age-related macular degeneration (AMD or ARMD) is by far the most common type. AMD is a disease associated with aging that gradually destroys sharp central vision that is needed for seeing objects clearly and for common daily tasks such as reading and driving. In some cases, AMD advances so slowly that people notice little change in their vision. In others, the disease progresses faster and may lead to a loss of vision in both eyes. AMD is the leading cause of vision loss in Americans 60 years of age and older. AMD usually affects both eyes, although the clinical appearance and degree of visual loss may vary a great deal between the two eyes.
AMD occurs in two forms. "Wet" age-related macular degeneration is less common but more aggressive in its progression to severe central vision loss. "Dry" age-related macular degeneration is the more common type and is more slowly progressive in causing visual loss..
What is wet age-related macular degeneration?
Wet AMD occurs when abnormal blood vessels grow from the choroid (the layer of blood vessels between the retina and the outer firm coat of the eye called the sclera) under and into the macular portion of the retina. These new blood vessels (known as choroidal neovascularization or CNV) tend to be very fragile and often leak blood and fluid. The blood and fluid raise the macula from its normal place at the back of the eye and interfere with the retina's function and causes the central vision to blur. Under these circumstances, vision loss may be rapid and severe. Some patients, however, do not notice visual changes despite the onset of CNV. Therefore, periodic eye examinations are very important for patients at risk for CNV.
Once CNV has developed in one eye, whether there is a visual loss or not, the other eye is at relatively high risk for the same change.
All wet AMD is described as advanced AMD, whether or not there is serious visual loss. Wet AMD does not have not have stages like dry AMD. The wet form generally leads to significantly more vision loss than the dry form.
All people who have the dry form of AMD are at risk for development of the wet form. All people who have the wet form had the dry form first. The dry form can advance and cause vision loss without turning into the wet form. The dry form also suddenly can turn into the wet form. Currently, there is no certain way to predict if or when the dry form will turn into the wet form.
What are retinal drusen?
Retinal drusen are yellow deposits under the retina. They often are found in people over 60 years of age. Your eye-care professional can detect drusen during a comprehensive dilated eye exam.
Drusen alone do not usually cause vision loss. In fact, scientists are unclear about the connection between drusen and AMD. It is not clear if an increase in the size or number of drusen raises a person's risk of developing either advanced dry AMD or wet AMD.
What is dry age-related macular degeneration?
In dry AMD, the light sensitive cells in the macula slowly break down. With less of the macula functioning, central vision diminishes. Dry AMD often occurs in just one eye at first. Later, the other eye can be affected. The cause of dry AMD is unknown.
Dry AMD has three stages, early, intermediate, or advanced, all of which may occur in one or both eyes. People with early AMD have either several small drusen or a few medium-sized drusen. At this stage, there are no symptoms and no vision loss.
People with intermediate AMD have either many medium-sized drusen or one or more large drusen. Some people see a blurred spot in the center of their vision. More light may be needed for reading and other tasks.
In addition to drusen, people with advanced dry AMD have a breakdown of light-sensitive cells and supporting tissue in the central retinal area. This breakdown can cause a blurred spot in the center of your vision. Over time, the blurred spot may get bigger and darker, taking more of your central vision. You may have difficulty reading or recognizing faces until they are very close to you.
The dry form is much more common than the wet form. In dry AMD, there is no CNV (abnormal new blood vessel formation under the retina) and no fluid or blood leakage into the retina (retinal swelling or bleeding). More than 85% of all people with intermediate and advanced AMD combined have the dry form. However, if only advanced AMD is considered, about two-thirds of patients have the wet form.
Dry AMD can advance and cause vision loss without turning into wet AMD. Dry AMD can also rapidly transform into the wet form by the growth of new blood vessels.
What are the symptoms for macular degeneration?
Dry macular degeneration symptoms usually develop gradually and without pain. They may include:
- Visual distortions, such as straight lines seeming bent
- Reduced central vision in one or both eyes
- The need for brighter light when reading or doing close work
- Increased difficulty adapting to low light levels, such as when entering a dimly lit restaurant
- Increased blurriness of printed words
- Decreased intensity or brightness of colors
- Difficulty recognizing faces
Dry macular degeneration usually affects both eyes. If only one eye is affected, you may not notice any changes in your vision because your good eye may compensate for the weak eye. And the condition doesn't affect side (peripheral) vision, so it rarely causes total blindness.
Dry macular degeneration is one of two types of age-related macular degeneration. It can progress to wet (neovascular) macular degeneration, which is characterized by blood vessels that grow under the retina and leak. The dry type is more common, but it usually progresses slowly (over years). The wet type is more likely to cause a relatively sudden change in vision resulting in serious vision loss.
When to see a doctor
See your eye doctor if:
- You notice changes in your central vision
- Your ability to see colors and fine detail becomes impaired
These changes may be the first indication of macular degeneration, particularly if you're over age 50.
What are the causes for macular degeneration?
No one knows exactly what causes dry macular degeneration. But research indicates it may be related to a combination of heredity and environmental factors, including smoking and diet.
The condition develops as the eye ages. Dry macular degeneration affects the macula — an area of the retina that's responsible for clear vision in your direct line of sight. Over time tissue in your macula may thin and break down.
What are the treatments for macular degeneration?
Wet AMD can be treated with laser surgery, photodynamic therapy, and injections into the eye. None of these treatments is a permanent cure for wet AMD. The disease and loss of vision may progress despite treatment.
Laser surgery is used to destroy the fragile, leaky blood vessels. A high energy beam of light is aimed directly onto the new blood vessels to eradicate them, preventing further loss of vision. However, laser treatment may also destroy some surrounding healthy tissue and some vision. Because of this, only eyes with new vessels away from the exact center of the vision can be treated. This represents only a small proportion of patients with AMD. Laser surgery is only effective in halting or slowing visual loss if the leaky blood vessels have developed away from the fovea, the central part of the macula. Even in treated cases, the risk of new blood vessels recurring after treatment is significant and further or other treatment may be necessary.
Photodynamic therapy uses a drug called verteporfin (Visudyne) being injected into a vein of the arm. A light is then directed into the eye to activate the drug adhering to the blood vessels in the eye. The activated drug destroys the new blood vessels and leads to a slower rate of vision decline. Photodynamic therapy may slow the rate of vision loss. It does not stop vision loss or restore vision in eyes already damaged by advanced AMD. Treatment results often are temporary. Retreatment may be necessary.
Learn more about: Visudyne
Within the last seven years, injections into the eye with drugs specifically developed to stop the growth of new blood vessels have revolutionized the treatment of wet macular degeneration. We have learned that a specific chemical called vascular endothelial growth factor (VEGF) is necessary for the new blood vessels to grow under the retina. Drugs that counter VEGF (anti-VEGF pharmacotherapy) can be injected into the eye to arrest development of new blood vessels and sometimes cause them to regress. These drugs are injected in the ophthalmologist's office and may need to be given as frequently as monthly. Careful observation of the eye on a monthly basis to determine the drug effect is necessary. With this treatment, visual loss can often be halted or slowed and some patients will even experience some improvement of vision. Newer drugs currently under review may need to be given less frequently. Photodynamic therapy and laser ablation have been largely, if not completely, abandoned in faver of VEGF inhibitors. New and more effective anti-VEGF medicines are on and approaching the market. If diagnosed and treated early, the patient's chances of a better outcome are improved.
In patients with far advanced macular degeneration on both eyes, surgery to implant a telescopic lens in one eye is an option. The telescope implant, which surgically replaces the eye's natural lens, magnifies images while reducing the field of vision (peripheral vision). The telescopic lens implant may improve both distance and close-up central vision.
What are the risk factors for macular degeneration?
Factors that may increase your risk of macular degeneration include:
- Age. This disease is most common in people over 65.
- Family history and genetics. This disease has a hereditary component. Researchers have identified several genes that are related to developing the condition.
- Race. Macular degeneration is more common in whites than it is in other people.
- Smoking. Smoking cigarettes or being regularly exposed to smoke significantly increases your risk of macular degeneration.
- Obesity. Research indicates that being obese may increase your chance that early or intermediate macular degeneration will progress to the more severe form of the disease.
- Cardiovascular disease. If you have had diseases that affected your heart and blood vessels, you may be at higher risk of macular degeneration.
Is there a cure/medications for macular degeneration?
Macular degeneration, also known as Age-related macular degeneration is a common eye disorder caused by the deterioration of the macula, a region in the center of the retina, present in the back of the eye.
Macular Degeneration is not a curable condition. Early diagnosis and proper treatment will slow the progression of the condition and aid in the management of the symptoms. Based on the severity of the disease and health status of the individuals, the treatments included are,
- Dietary supplements – Intake of a specific combination of vitamins and minerals might slow down the progress of the condition.
- The nutritional supplements include Vitamin C, Vitamin E, lutein, zinc, copper, zeaxanthin, and beta carotene.
- Anti-vascular endothelial growth factor (anti-VEGF) drugs – The healthcare professional will inject the individual with anti-VEGF medications, including Ranibizumab and aflibercept, direct into the eye to prevent the growth of new blood vessels.
- Photodynamic therapy – Photodynamic therapy involves the injection of medication in one of the arms and involves a special laser treatment to close the leaking blood vessels. It will improve the vision, even though it takes multiple treatment procedures.
- Photocoagulation – Photocoagulation uses high-energy laser beams to eliminate abnormal blood vessels.
High blood pressure,Depression,Anxiety,Visual hallucinations
Bevacizumab (Avastin),Ranibizumab (Lucentis),Aflibercept (Eylea),Brolucizumab (Beovu)
Blurred (low) vision,Blank or dark spots in vision,The appearance of dark or blurry areas in the center of your vision,Worsen or different color perception