Vision is something that we depend on every day. It allows us to be productive and get our daily tasks done without delay.
As people age, they often start to experience problems with their vision. Several eye-related diseases can develop. Some of these conditions can even lead to a complete loss of vision.
Macular degeneration is generally considered an age-related eye disease. It is most often found in people over 60 years of age. Some people experience permanent vision loss with the condition.
We take a look at what macular degeneration is. This post also looks at the different types of the condition. We consider the causes and risk factors associated with the disease too.
What Is Macular Degeneration?
Macular degeneration is an eye disease. It is associated with age. The condition is often referred to as Age-Related Macular Degeneration. It is also called AMD for short.
Among senior citizens, macular degeneration is considered the leading cause of permanent vision loss. The condition develops gradually over time.
Severe macular degeneration will not always cause complete blindness. It generally affects the central vision of the patient. The condition does cause severe problems with vision, however. Even when it does not cause complete blindness, vision problems can severely impact a patient’s day-to-day activities.
While macular degeneration is generally associated with age, younger individuals can also be affected. There are cases where children develop macular degeneration too. In such a case, it will be caused by a specific form of macular degeneration.
The macula is affected by this condition. This is the central region of the patient’s retina. It is a small part of the retina. This part of the eye is a light-sensing nerve. The nerve tissue sits at the back of the patient’s eye. The macula wears down over time. This is what eventually causes the development of macular degeneration.
In the United States, it is estimated that over 10 million people are affected by macular degeneration. It is more common that bot glaucoma and cataracts. By the year 2050, it is estimated that at least 22 million people in the United States will be affected by the condition.
The epidemiology of the condition is even greater when looking at a worldwide population. Worldwide, there are about 170 million people with macular degeneration. This accounts for senior citizens, young adults, and children affected by the disease.
The condition is currently considered incurable. There are no cures available for patients with macular degeneration. A few treatments have been identified that may help to reduce the rate at which the condition develops.
Stages of Macular Degeneration
The condition is often divided into multiple stages. There are three specific stages that doctors use to diagnose macular degeneration. Here is a quick overview of the stages:
- Early Macular Degeneration: Early AMD does not cause any central vision loss. Drusen will start to collect during an early stage of macular degeneration. The drusen will be medium in size when diagnosed with early macular degeneration.
- Intermediate Macular Degeneration: Intermediate AMD is when the disease has started to progress. Some degree of vision loss is expected at this stage. The symptoms will not be disruptive. Larger drusen collections will be present in the macula.
- Late Macula Degeneration: Late AMD is a more serious form of the condition. The patient will be able to notice the central vision loss caused by macular degeneration at this point. It is also more difficult to provide the patient with treatment to slow the disease’s progression at this point.
A thorough examination will be needed to help with the diagnosis of this eye disease. This ensures the optometrist can see the size of the drusen. It also allows the eye specialist to determine the severity of the condition and diagnose a specific type of macular degeneration.
Types Of Macular Degeneration
Macular degeneration is a general term that may describe two specific diseases. The two diseases are closely related to each other. There are, however, a few essential differences between the two conditions.
Patients must be able to distinguish between the two types of macular degeneration. This will ensure a person is able to better understand what they should expect. It also ensures the patient knows how the condition may affect their vision in the future.
Dry Macular Degeneration
When a person is diagnosed with macular degeneration, there is a 90% chance that it will be the dry form of the disease. This is the most common type of eye-related condition.
The dry form is associated with the collection of drusen in the macula. Drusen is a term that refers to yellow deposits. These deposits may not cause serious problems during an early stage of macular degeneration. The yellow deposits mainly consist of proteins and small pieces of fat. The drusen generally tend to become bigger over time. This is when the condition becomes a more noticeable problem. Vision will start to become distorted when the drusen grow larger.
Some patients describe this as a dimmed vision. The light-sensitive tissue that makes up the macular also starts to become thinner with an increased collection of yellow deposits. As the deposits continue to collect, the light-sensitive cells that are located in the patient’s macula may eventually die. Central vision may be lost when the light-sensitive cells die. This process generally started with blind spots that affect the central vision. This later becomes a more noticeable problem.
Wet Macular Degeneration
The wet form of macular degeneration is not as common as the dry type. Among people diagnosed with macular degeneration, only about 10% will have the wet form. This particular form of macular degeneration is associated with blood vessels.
There are blood vessels that grow underneath the macula. These blood vessels supply the cells in the region with blood. Wet AMD is associated with a leak from these blood vessels. Blood leaks from the vessels. The retina is then filled with the blood. Additional fluids may also leak into the retina.
When a patient has wet macular degeneration, vision distortion is generally the most common problem. When looking at a straight line, the line may appear wavy. This type of macular degeneration also causes blind spots. Similar to dry AMD, the patient’s central vision will be affected by the condition.
The blood in the retina generally causes scars to form in the retina. This affects the macula too. In turn, the scarring can cause a permanent loss of the patient’s central vision.
Macular Degeneration Symptoms
Advanced AMD is harder to treat than early AMD. This is why people are advised to see an eye doctor regularly. This allows for the detection of peripheral vision problems, neovascular AMD, and abnormal blood vessels during an eye exam.
The eye condition can cause a few symptoms. As one of the retinal diseases, the patient may generally find that their central vision will be affected. AMD patients should look out for these symptoms:
- Blurred vision is common among people with macular degeneration.
- There may be dark areas that affect the central vision.
- Whiteout sometimes appears at the center of a patient’s vision.
- The patient’s color perception may also change. This, however, is a rare symptom of macular degeneration.
- Straight lines may seem distorted to the patient.
The symptoms can come on suddenly. In most cases, however, they develop gradually. It can take several years for the disease to progress to a point where symptoms are noticeable. The center vision loss will continue to progress.
Macular Degeneration Causes
A particularly problematic factor related to macular degeneration is that researchers have not yet been able to provide an accurate view of the cause. It is not currently known exactly where the drusen come from.
Researchers have reported that the drusen consist of both fats and proteins. It is suggested that this debris may come from the retina, but more conclusive evidence is needed to confirm such speculations.
Researchers do note that macular degeneration is a complex disease. Both environmental and hereditary factors need to be taken into consideration. Researchers are still looking at reasons why the macula cells start deteriorating. One such research has been completed; there may be more hope for people with this condition.
It is also important to differentiate between Stargardt disease and AMD at this point. Stargardt disease is sometimes also referred to as juvenile macular degeneration. This condition affects children, as well as young adults. The specific causes that are linked to these conditions are different.
With Stargardt disease, genetics are generally the main point of concern. The individual will be too young for environmental factors to make a significant impact on eye health.
When looking at age-related macular degeneration, however, environmental factors are often the main focus point. Several environmental factors affect the eye over a few decades. This eventually affects the retina and, in particular, the nerve tissue that makes up the macula.
Little is currently known about why exactly macular degeneration develops. Researchers do know that the causes behind the disease in young and older individuals are likely not the same.
Through years of research, certain risk factors have been identified. These risk factors help people understand how likely they may be to develop macular degeneration. Age is considered the most critical risk factor associated with macular degeneration.
In most cases, the disease is only diagnosed in people older than the age of 55. Thus, senior citizens have the highest risk of macular degeneration. Even though the condition also affects younger people, the risk is much lower among these individuals.
Researchers have also identified other risk factors. We take a look at these risk factors below.
- Genetics: Genetics do seem to play a role in the risk of developing macular degeneration. There seem to be genetic links to both Stargardt disease, as well as age-related macular degeneration. If a person has a family history of the disease, they are more likely to develop it. This is an unavoidable risk factor. It means that the risk factor cannot be changed or used as a strategy to help prevent macular degeneration.
- Race: Some research has suggested that a person’s race also plays a role in the risk of macular degeneration. The prevalence of macular degeneration is the highest among Caucasian patients. Thus, being Caucasian means a person may be more likely to develop the condition.
Researchers have compared the prevalence of the disease to Hispanics, Latinos, and African-Americans. The prevalence of macular degeneration was significantly lower among these races, particularly when compared to Caucasian citizens. Similar to genetics, race is another unavoidable risk factor. It means there is nothing a person can do to reduce the risk of macular degeneration caused by race.
- Lifestyle Habits: Some lifestyle habits may contribute to the development of this eye disease. The primary risk factor that we have to mention here would be smoking. The Center for Disease Control and Prevention reports that an estimated 13.7% of American adults are currently smokers. This calculates to about 34 million adults in the country.
Over half of these individuals have some type of disease that is caused by smoking. This lifestyle habit causes many adverse effects on the human body. It affects the eyes too – especially the smoke that is blown out of the patient’s mouth. Blood vessels throughout the body are also affected by smoking. The combined effects can adversely affect the eyes – and, in turn, create a higher risk of macular degeneration. This is an avoidable risk factor.
Diagnosing Macular Degeneration
A patient will generally need to see an ophthalmologist in order to get macular degeneration diagnosed. Other retinal diseases can also cause similar symptoms. Thus, a thorough eye examination will be needed. The ophthalmologist may need to conduct a few tests to provide an accurate diagnosis.
During these tests, there are a few things that the doctor needs to take into account. They need to look at whether or not drusen has collected at the retina.
The doctor also needs to look at blood vessels behind the retina. Both of these factors need to be considered. This helps the eye doctor diagnose a specific type of macular degeneration.
It also ensures the doctor is able to determine the severity of the condition. Appropriate treatment can then be prescribed to the patient.
Some of the tests that may be conducted to help with the diagnosis include:
- Dilation: Special drops are placed in the eye. This allows the pupils to dilate. The doctor then examines the back of the patient’s eyes. A special instrument is used during this process. It allows the doctor to see the blood vessels at the back of the retina. It also ensures the doctor can see if there is a collection of drusen.
- Amsler grid: An Amsler grid test may also be conducted. This test will provide details on defects related to the patient’s central vision. The patient may find that straight lines appear distorted or broken.
- Fluorescein Angiography: A colored dye is injected into a vein in the patient’s arm. The dye will travel toward the eye. It highlights any blood vessels. A camera is then used to take pictures of the blood vessels.
Other tests include an optical coherence tomography and an indocyanine green angiography.
Preventing Macular Degeneration
There is no cure for macular degeneration. This is why patients are advised to do what they can to help reduce their risk of eye disease.
- Smokers need to consider giving up the habit. Smoking is one of the major risk factors associated with macular degeneration. If a patient stops smoking, their risk may decrease.
- Eye health can also be protected by maintaining a healthy weight. This reduces the risk of diabetes, a condition that damages nerves in the eyes. Patients should also ensure they maintain a normal blood pressure level.
- Frequent exercise and a diet that is rich in essential nutrients are important. Exercise helps to regulate blood pressure and assists with weight management. Eating a healthy diet ensures the eyes gain access to certain essential nutrients.
Macular degeneration causes vision difficulties. The condition is associated with a deterioration of the macula. It generally affects the central vision. There are two types of macular degeneration.
Severe vision loss can occur with advanced AMD. Some people may experience blurred vision during the earlier stages. Some strategies help to reduce the risk of macular degeneration. Treatments generally focus on reducing the rate at which the macular degenerates over time.