Macumira

About AMD

What is Age-Related Macular Degeneration?

Overview of Age-Related Macular Degeneration (AMD)

Age-Related Macular Degeneration (AMD) is a disease of the eye, and the leading cause of vision loss in older adults. It’s estimated 2.5 million Canadians suffer from some form of AMD.1

It begins when a part of your retina called the macula becomes damaged. The macula is part of the retina at the back of the eye. It is responsible for our central vision, most of our colour vision and the fine detail of what we see.2

AMD can progress slowly in some people, and its early stages almost always have no noticeable symptoms3. However, it can also progress rapidly. AMD tends to affect older people4, though there are rare cases when younger people are affected — usually related to an underlying condition. 

What are the symptoms of Age-Related Macular Degeneration?

In early-stage AMD, you often will have no recognizable symptoms. However, AMD is a progressive disease, meaning it gets worse over time. The early noticeable symptoms tend to be slight blurring in your central vision, straight lines appearing slightly blurry, and trouble performing tasks like reading or driving in low light.

In its later stages AMD, central vision can become very blurry or completely dark. Straight lines become very wavy and tasks like reading and recognizing faces becomes difficult5.

AMD does not necessarily affect both eyes; it can also affect one, or both at different rates of progression.

Because AMD affects central vision, it does not lead to total blindness. However, in advanced stages it can significantly compromise quality-of-life. 

Symptoms of Age-related Macular Degeneration

Early-stage

  • The early stages of AMD have no noticeable symptoms, though a health-care professional can help detect it with testing.

Intermediate-stage

  • Sometimes, people with more advanced thinning of the macula are asymptomatic
  • Slight blurriness in the centre of your vision
  • Difficulty seeing in low light

Late-stage

  • Significant blurring or dark spots in central vision
  • Straight lines can appear very wavy
  • Dulling of colours

What factors put people at risk for AMD?

It is not known exactly what causes AMD, but there are known factors that put people at risk.
Risk factors for Age-Related Macular Degeneration6
  • Increased age
  • Extensive UV light exposure
  • Cardiovascular disease
  • A diet high in saturated fat (foods like butter, fatty meat, and cakes)
  • Smoking
Additionally, studies show that Caucasian people and people with a family history of AMD are also at higher risk.

What is the difference between Dry and Wet Age-Related Macular Degeneration?

There are two classifications of AMD:
Dry AMD is the more common form, accounting for 85–90% of AMD cases. Dry age-related macular degeneration (AMD) is a gradual deterioration of the macula as the retinal cells die off and are not renewed7. Because dry AMD happens due to gradual thinning, it begins as early-stage and progresses. While early thinning doesn’t cause any symptoms, intermediate- and late-stage AMD causes blurring or blank spaces in central vision, dulling of colours and trouble seeing in low light.
This form is less common but much more serious. Wet AMD is when new, abnormal blood vessels grow under the retina. These vessels may leak blood or other fluids, causing scarring of the macula. You lose vision faster with wet AMD than with dry AMD8. The presence of blood or fluid is why it is known as “wet” AMD. Wet AMD develops from the dry form, and it can develop at any point in the progression of dry AMD — from early to late.

How is AMD diagnosed?

An eye doctor can perform a simple test to determine if you have AMD. If you believe you may be at risk, the good news is that a test can identify AMD before there are noticeable symptoms. So, it’s important to get your eyes examined regularly — especially if you have risk factors.

Before a test, the doctor will ask about family history, risk factors, and other information.

During an eye exam, your ophthalmologist may ask you to look at an Amsler grid. This grid helps you notice any blurry, distorted, or blank spots in your field of vision. They will also look inside your eye through a special lens, which will help them see if there are changes in the retina and macula9.

Optical coherence tomography (OCT) is another way to look closely at the retina. A machine scans the retina and provides very detailed images of the retina and macula.
Your doctor may do fluorescein angiography to see what is happening with your retina. Yellow dye (called fluorescein) is injected into a vein, usually in your arm. The dye travels through your blood vessels. A special camera takes photos of the retina as the dye travels throughout its blood vessels. This shows if abnormal new blood vessels are growing under the retina10

What is the difference between Dry and Wet Age-Related Macular Degeneration?

There are two classifications of AMD:
Dry AMD is the more common form, accounting for 85–90% of AMD cases. Dry AMD happens when the macula thins over time. Because dry AMD happens due to gradual thinning, it begins as early-stage and progresses. While early thinning doesn’t cause any symptoms, intermediate- and late-stage AMD causes blurring or blank spaces in central vision, dulling of colours and trouble seeing in low light.
Wet AMD is always late-stage and has severe symptoms. It is caused by abnormal growth of blood vessels into the macula, or by fluid accumulating in the back of the eye. The presence of blood or fluid is why it is known as “wet” AMD. Wet AMD develops from the dry form, and it can develop at any point in the progression of dry AMD — from early to late.

How is AMD diagnosed?

An eye doctor can perform a simple test to determine if you have AMD. If you believe you may be at risk, the good news is that a test can identify AMD before there are noticeable symptoms. So, it’s important to get your eyes examined regularly — especially if you have risk factors.

Before a test, the doctor will ask about family history, risk factors, and other information. The most common test involves an examination of your eyes with a microscope after eye drops have been applied. Other tests can help confirm a diagnosis, after which you can work with your health-care provider to develop a prevention or treatment plan. 

How is AMD diagnosed?

An eye doctor can perform a simple test to determine if you have AMD. If you believe you may be at risk, the good news is that a test can identify AMD before there are noticeable symptoms. So, it’s important to get your eyes examined regularly — especially if you have risk factors.

Before a test, the doctor will ask about family history, risk factors, and other information. The most common test involves an examination of your eyes with a microscope after eye drops have been applied. Other tests can help confirm a diagnosis, after which you can work with your health-care provider to develop a prevention or treatment plan. 

What is the difference between Dry and Wet Age-Related Macular Degeneration?

There are two classifications of AMD: Dry AMD and wet AMD.

Dry AMD

Dry AMD is the more common form, accounting for 85–90% of AMD cases. Dry AMD happens when the macula thins over time. Because dry AMD happens due to gradual thinning, it begins as early-stage and progresses. While early thinning doesn’t cause any symptoms, intermediate- and late-stage AMD causes blurring or blank spaces in central vision, dulling of colours and trouble seeing in low light.

Wet AMD

Wet AMD is always late-stage and has severe symptoms. It is caused by abnormal growth of blood vessels into the macula, or by fluid accumulating in the back of the eye. The presence of blood or fluid is why it is known as “wet” AMD. Wet AMD develops from the dry form, and it can develop at any point in the progression of dry AMD — from early to late.