In this advanced form of macular degeneration, abnormal blood vessels leak fluid and blood into the macula, leading to severe damage.

Neovascular age-related macular degeneration (NVAMD), or wet AMD, is an advanced form of macular degeneration, a progressive eye disease that affects the macula. The macula is the central part of the retina responsible for sharp, central vision.

In NVAMD, abnormal blood vessels grow beneath the macula, causing damage and leading to vision loss.

NVAMD is classified as wet because it involves the presence of fluid and blood in the macula due to the leaking of abnormal blood vessels.

NVAMD is the more advanced and severe form of AMD, and it’s always preceded by dry AMD. But not all dry AMD turns into NVAMD.

The symptoms of NVAMD can include:

  • Blurred or distorted central vision: Objects may appear blurry or distorted, making it difficult to read, recognize faces, or perform activities that require detailed vision.
  • Loss of central vision: There may be a dark or empty area in the center of your vision, affecting your ability to see clearly.
  • Straight lines appearing wavy: Straight lines may appear distorted or wavy, a phenomenon known as metamorphopsia. Research suggests that people with wet AMD had more incidences of horizontal and vertical metamorphopsia, which causes linear objects to look curvy or round, compared with dry AMD.
  • Dark or blind spots: You may experience blind spots or areas of decreased vision in your central field of view.
  • Decreased color perception: Colors may appear less vibrant or washed out.
  • Difficulty with low light or night vision: It may become more challenging to see in dimly lit environments or during nighttime.

NVAMD is considered an advanced form of AMD, and it’s always preceded by the dry form. There is no early or intermediate stage of NVAMD.

The progressive stages of dry-to-wet AMD can be summarized as follows:

  • Early dry AMD: The earliest stage of AMD is characterized by the presence of small yellow deposits called drusen beneath the macula. At this stage, there may be no noticeable vision changes.
  • Intermediate dry AMD: Drusen become larger and more numerous, potentially causing mild to moderate vision changes. Some people may experience distortion or blurriness in their central vision.
  • Late dry AMD: Also known as geographic atrophy, this stage involves the gradual loss of cells in the macula, leading to significant vision impairment. Central vision becomes progressively blurry or dark, affecting daily activities.
  • Wet AMD: In some cases, dry AMD progresses to wet AMD. Abnormal blood vessels called choroidal neovascularization grow beneath the macula, which can leak blood and fluid, causing sudden and severe vision loss. Wet AMD is considered the advanced and more severe form of AMD.

It’s important to note that not all individuals with dry AMD will progress to wet AMD. Dry AMD can progress and cause vision loss without transitioning to the wet form.

How long does it take macular degeneration to progress to blindness?

While much less common than dry AMD, NVAMD accounts for almost 90% of AMD-related vision loss.

The time it takes for a person with NVAMD to experience total vision loss can vary significantly from person to person. In some cases, macular degeneration progresses slowly over many years, while in others, it may progress more rapidly.

It’s important to note that not everyone with NVAMD will experience total vision loss. Some individuals may retain some degree of vision.

Research suggests macular degeneration is primarily caused by a combination of genetic and environmental factors, including:

  • Age: The risk of macular degeneration increases with age, especially after age 50.
  • Genetics: Family history of macular degeneration increases the likelihood of developing the condition.
  • Smoking: Smoking significantly increases the risk of AMD. People who smoke are up to four times more likely to develop AMD than people who do not smoke.
  • Race: Macular degeneration is more common in White people.
  • Cardiovascular health: Conditions such as hypertension, high cholesterol, and obesity can contribute to the development of macular degeneration.
  • Sun exposure: Research from 2019 suggests that prolonged and unprotected exposure to sunlight may increase the risk of AMD.

How common is neovascular age-related macular degeneration?

According to research from 2021, AMD is the most common retinal disease in the Western world, with the advanced form affecting 1–3% of the population. In 2020, AMD affected about 196 million people worldwide. This number is projected to increase to 288 million by 2040.

Wet AMD accounts for about 10% of all AMD cases. The prevalence of neovascular AMD increases with age, with the highest rates seen in people over age 75.

The treatment options for NVAMD aim to slow the progression of the disease and to preserve vision.

One of the primary treatment approaches is the use of anti-vascular endothelial growth factor medications. These medications are injected into the eye to inhibit the growth of abnormal blood vessels and reduce leakage in the macula. This helps improve vision and prevent further damage.

Other treatment modalities, such as photodynamic therapy and laser therapy, may also be used in certain cases.

NVAMD, or wet AMD, is an advanced form of AMD, a serious eye condition that can cause significant vision loss if not treated.

Regular eye exams and monitoring are crucial to detect any signs of AMD progression and to determine the appropriate treatment options. Early intervention and management can help slow its progression and preserve vision.