What Is Dry Macular Degeneration?

Dry macular degeneration, also called age related macular degeneration, is a progressive eye condition that affects adults, typically over the age of 60. It usually doesn’t cause symptoms in the early stages, but it may cause gradual vision loss as it progresses.

There are a number of risk factors associated with dry macular degeneration, including smoking and a family history of the condition. Because of the lack of symptoms, routine vision screening is important to identify early signs of dry macular degeneration—as well as other eye diseases. 

If you have this condition, it's important that you follow recommendations to avoid deterioration of your vision. There is no medication or procedure approved for treating age-related macular degeneration, but there are several medical and surgical options that are being investigated in research trials.

Advanced dry macular degeneration can develop into more serious eye problems, and there are prescription medications and interventional procedures that can help alleviate some of the effects of these more serious eye conditions. 

Dry Macular Degeneration Symptoms

You might not notice any symptoms of dry macular degeneration. As the condition advances, you can develop subtle vision loss. It is hard to specifically recognize the visual changes of early macular degeneration because aging is associated with several other eye problems and types of vision loss—and the effects often feel very similar. 

If they do occur, symptoms of dry macular degeneration include:

• Difficulty reading: Reading issues may be the first problem you notice as your macular degeneration advances. It can be hard to see details in small print, and you may find yourself using a magnifying glass or making the font bigger on your phone or computer. 
• Blurred vision: You may feel that the edges of objects are unclear or that they are not sharp.
• Diminished night vision: With dry macular degeneration, your vision may be worse when you are not in a well-lit area. Initially, you might not be sure if this is related to tiredness at night or lack of lighting.
• Decreased color vision: Colors can appear faded and dull. Objects that you used to see as bright might not look so bright anymore to you.
• Reduced central vision: While it is difficult to be able to detect this detail, dry macular degeneration affects central vision, leaving your peripheral vision from the sides of your eyes unaffected by the vision loss.

Dry macular degeneration usually involves both eyes to approximately an equal degree. 

Complications 

Dry macular degeneration can advance to geographic atrophy or wet macular degeneration, which are more serious diseases of the retina. These advanced eye conditions aren't necessarily associated with each other and they don’t cause each other. You can develop both geographic atrophy and wet macular degeneration. 

• Geographic atrophy: This is considered to be the last, most severe stage of dry macular degeneration. This is a thinning of the macula (called "geographic" because it has a map-like appearance on examination), and it causes more noticeable vision loss than dry macular degeneration. 
• Wet macular degeneration: In its most severe form, dry macular degeneration can increase the risk of wet macular degeneration. Wet macular degeneration is a condition in which new blood vessels grow around the macula and leak blood or fluid.

Causes

You may be predisposed to dry macular degeneration if you are a smoker, have cardiovascular disease or obesity, or have a family history of dry or wet macular degeneration. 

Dry macular degeneration is a progressive process. The macula is a structure in the eye that detects light. It is the central area of the retina, located at the back of the eyeball. As dry macular degeneration develops, this structure becomes thin as the cells atrophy (shrink and die). Over time, the macula begins to lose its function, resulting in vision loss.

Eye Damage

Experts suggest that oxidative damage plays a role in the disease process of dry macular degeneration. Oxidation is a chemical process that occurs in normal metabolism, so all cells in the body are exposed to a reasonable amount of oxidation. Excess oxidation, however, causes damage.

It has been suggested that the mitochondria of the retinal cells, which are the energy-producing parts of the cell, may be especially susceptible to oxidative damage in dry macular degeneration. Inflammation may play a role as well. As dry macular degeneration worsens, there is an increase in complement activity, which is a marker of inflammation.

The risk factors associated with dry macular degeneration, including aging, may increase the predisposition to macular oxidative damage. 

Genetics

There is a hereditary component to dry macular degeneration. The genetics of this condition are believed to be related to genes that promote inflammation. An increase in complement activity (a marker for inflammation) is more prominent in people who have genetic markers that are consistent with complement overactivity.

Drusen

Dry macular degeneration is associated with drusen, which are yellowish deposits of fats and protein that form within the retina. Drusen can contribute to vision loss. It isn’t known whether drusen are a cause of dry macular degeneration or whether they are caused by the condition.

Diagnosis

Even if you don’t have a history of eye problems, it’s a good idea to have your eyes and vision checked on a regular basis after you reach age 40. Age related vision loss can cause headaches, difficulty reading, and may lead to accidents while driving.

Since early-stage dry macular degeneration doesn’t usually cause symptoms, you might be diagnosed with this condition without having any complaints about your eyes or your vision. 

Your diagnostic tests may include a vision examination and examination of your eyes, including your macula.

Vision and Eye Test

A standard eye examination includes observation of your eyes and a vision examination. Your healthcare provider will begin by looking at your eyes to see if there is any obvious trauma or discoloration, such as redness or yellowness. Your healthcare provider will also observe your eye movements as you move them side to side and up and down.

Your healthcare provider may examine your color vision by asking you to name colors and to identify subtle color differences. Your central vision and peripheral (side) vision will be tested as well. Your visual acuity is an assessment of your ability to see details, such as letters, both near and far.

With dry macular degeneration, you may have diminished visual acuity and color vision in your central vision. Your peripheral vision shouldn’t be affected, especially at the early stages. Your eyes and eye movements should appear normal.

Fundoscopic Examination

Your healthcare provider may look at the structures inside of your eye with a fundoscopic examination, which is a non-invasive test. With a fundoscope, your healthcare provider can look inside your pupils from a few inches away to see the structures in the back of your retina, including your macula, the blood vessels, and the optic nerve. Drusen might be detected with this test as well.

You might have a dilated eye exam. Your healthcare provider might put drops in your eyes to dilate (widen) your pupils (the dark area of your eye). This helps with the visualization of your macula with fundoscopic examination and other non-invasive imaging tests. Dilation of your eyes is safe, but your vision will be blurred for several hours afterward until the medication wears off. 

Other non-invasive imaging tests you might have include: 

• Fundus autofluorescence: This imaging test uses blue or green light to highlight a substance called lipofuscin, the presence of which indicates damage in the retina. 
• Optical coherence tomography (OCT): This is an imaging test that visualizes the retina. 
• Multifocal electroretinography: This test helps detect the function of the retina by evaluating its electrical activity in response to light stimulation.
• Ocular tonometry: This test measures intraocular pressure, which is the fluid pressure behind the eye.

Treatment

Treatment of this condition is focused on preventing its progression. There is no medical or surgical treatment that can reverse or stop the progression of dry macular degeneration. Smoking cessation and management of diabetes, heart disease, hypertension, and obesity are recommended to help prevent progression to wet macular degeneration.

General recommendations for the prevention of geographic atrophy include getting adequate vitamin intake, which experts suggest may prevent further oxidative damage.

According to the American Academy of Ophthalmology, there are no approved treatments indicated for dry macular degeneration. There are several products in development that are being evaluated in clinical trials for their safety and effectiveness as possible treatments for dry macular degeneration. 

Stem Cells

Stem cell transplant is being studied as a possible way to surgically replace macular cells. This may reverse or slow down dry macular degeneration. This procedure involves the injection of stem cells into the retina, and experts aren’t sure how often the injections would need to be repeated for it to be effective. 

Apl-2

Apl-2 is a new medication that is not currently available that is being investigated as a potential treatment for dry macular degeneration and geographic atrophy. It is injected into the eye. It is a complement factor 3 (C3) inhibitor that may prevent the deterioration of the macula by counteracting the inflammatory effects of complement protein.

Zimura

Zimura (avacincaptad pegol) is a new medication under research that is not currently available. It is in research trials as an emerging treatment for geographic atrophy and dry macular degeneration. It is placed directly into the eye by injection. This treatment inhibits part of the inflammatory process and is believed to work by protecting the macula from inflammatory damage.

Oracea

Oracea is a pill that is taken orally. It contains doxycycline, an antibiotic that has been in use for many years. It is being tested as a potential treatment for dry macular degeneration. It is believed to have potential anti-inflammatory action that may help in treating dry macular degeneration.

According to the American Academy of Ophthalmology, it may be available as a treatment for dry macular degeneration as early as 2021. The side effects noted in the experimental trials using Oracea for dry macular degeneration are similar to those of doxycycline and include rash, sun sensitivity, and stomach upset.

Metformin

Metformin is a commonly used treatment for diabetes. It is a pill taken by mouth. It is also being tested as a potential treatment for dry macular degeneration. Preliminary research on its effects in dry macular degeneration has been promising. The method by which it is believed to affect dry macular degeneration is by reducing inflammation, which can reduce oxidative damage.

Risuteganib

Risuteganib is a new medication that is being studied as a potential treatment for dry macular degeneration. It is injected into the eye, and it may have an effect in reducing oxidative damage. Risuteganib is an anti-integrin peptide that may stabilize the integrin protein. This protein is a structural stabilizing component of all the cells in the body, including cells of the macula. 

D609 

D609 is a new substance that is being investigated as a possible injectable therapy. Research has begun to establish it as a safe substance and has shown preliminary evidence that it may help protect the macula from advancing dry macular degeneration. It has been suggested that it may work as an antioxidant, preventing damage and degeneration of the macula.

Treatment of Advanced Complications 

There are medications and interventional procedures used for treating wet macular degeneration and geographic atrophy. These treatments do not reverse the conditions but may prevent progression.

Eylea (aflibercept), for example, is an injectable treatment approved for treatment of wet macular degeneration.

A Word From Verywell

Dry macular degeneration is the most common type of macular degeneration. Even if you don’t have any vision problems, it is best if you schedule an eye examination at age 40, and ask your healthcare provider how often you should follow up with have regular eye examinations. 

Several different potential treatments for dry macular degeneration are being investigated in clinical trials, but there is not currently any medication approved for managing the disease. If you are diagnosed with dry macular degeneration, you can take some steps to prevent its progression. 

It is also important to carefully manage other issues that contribute to vision loss, including diabetes. Your eye health has a major impact on your quality of life.