Wet AMD: From symptoms to treatment options

Wet age-related macular degeneration (AMD) is a serious eye condition that can lead to significant vision loss if not promptly treated.

Here, Mr Narendra Dhingra, renowned consultant ophthalmologist, offers an expert insight into wet AMD, including symptoms and treatment.

What is wet AMD?

Wet AMD is a chronic eye condition that causes blurred vision or a blind spot in the centre of the field of vision. The condition occurs due to the growth of abnormal blood vessels under the retina, which leak fluid or blood into the macula (the central part of the retina responsible for sharp, detailed vision). This leakage damages the macula and can result in rapid and severe vision loss.

What are the differences between wet AMD and dry AMD?

Age-related macular degeneration comes in two forms: dry and wet.

Dry AMD is more common, accounting for 85-90% of AMD cases. It progresses slowly, causing gradual vision loss, and is characterised by the thinning of the macula and the presence of drusen, which are small yellow deposits of fatty proteins under the retina. Symptoms of dry AMD include blurred vision and difficulty recognising faces or reading.

Wet AMD is less common but more severe, representing 10-15% of AMD cases. It progresses rapidly and can lead to significant vision loss within a short period. Symptoms of wet AMD include sudden vision changes such as distorted or wavy lines, dark spots in the centre of the field of vision, and the rapid loss of central vision.

How is wet AMD detected and diagnosed?

Early detection and diagnosis of wet AMD are crucial for effective treatment and preservation of vision.

A comprehensive eye examination is the first step for diagnosing wet AMD. During the exam, the specialist will perform a visual acuity test to measure how well the patient can see at various distances. A dilated eye exam will be performed as well, where eye drops will be used to widen (dilate) the patient’s pupils. This will allow the specialist to examine the retina and macula more thoroughly for any signs of AMD.

Subsequently, other diagnostic procedures may include:

Amsler grid test: The Amsler grid test is a test that helps identify any distortions or wavy lines in the patient’s vision, which are indicative of AMD. During the test, the patient will look at a grid of straight lines; any distortions will signal potential problems with the macula.

Optical coherence tomography (OCT) scans: An OCT scan is a non-invasive imaging test that provides detailed cross-sectional images of the retina, showing any thickening, swelling, or fluid accumulation in the retina, which are common in wet AMD. This test is crucial for detecting and monitoring the extent of damage caused by wet AMD.

OCT angiography: This is a non-invasive imaging test which can show the presence of wrong kind of blood vessels, new vessels at the back of the eye, by detecting blood flow through them. This avoids the need of fluorescein angiography in most cased, which is an invasive test

Fluorescein angiography: Fluorescein angiography is a test involves injecting a fluorescent dye into a vein in the arm and taking a series of images as the dye travels through the retinal blood vessels. This test helps identify any leakage from abnormal blood vessels and maps out the extent of blood vessel growth under the retina.

What treatment are available for wet AMD?

The primary goal of treatment for wet AMD is to stop or slow the growth of abnormal blood vessels and reduce fluid leakage. While there is no cure for wet AMD, treatment can significantly improve the outlook for patients, helping to preserve vision and improve quality of life.

Treatment options for wet AMD typically include:

Anti-VEGF injections: Anti-VEGF (vascular endothelial growth factor) injections are the most common and effective treatment for wet AMD, helping to inhibit the growth of abnormal blood vessels. The injections are administered directly into the eye, under local anaesthesia. They are effective in most cases and prevent further reduction of vision. The injections are done frequently in the first year and the frequency reduces with time. The side-effects are minimal to general health are minimal

Photodynamic therapy: Photodynamic therapy involves the use of a light-activated drug which is injected into a vein in the arm and travels to the abnormal blood vessels in the eye. A special laser then activates the drug, which destroys the abnormal blood vessels while sparing the surrounding tissue.

In addition, lifestyle changes such as quitting smoking, eating a healthy diet rich in leafy vegetables and fish, controlling blood pressure and cholesterol, and exercising regularly, can also help manage wet AMD.

How often will I need treatment for wet AMD?

The frequency and duration of the treatment for wet AMD can vary depending on the severity of the condition and how well the patient responds to therapy.

With anti-VEGF injections, the patient will initially receive injections every 4 to 8 weeks. The frequency will then decrease based on the patient’s response to the treatment. Some patients may require ongoing injections indefinitely to maintain vision.

You can schedule an appointment with Mr Dhingra on his Top Doctors profile.