Macular disease is the biggest cause of sight loss in the UK and age-related macular degeneration, or AMD, is the most common type of the condition[i]. There are two types of AMD, known as ‘dry’ and ‘wet’. Currently wet AMD is the only form of the condition which is treatable[ii]. Approximately 39,800 people in the UK develop wet AMD each year[iii].
Structure of the eye
Image source: iStock
The macula is part of the retina at the back of the eye. It is only about 5mm across but is responsible for all of our central vision, letting us see colour and fine details. The macula has a high concentration of special cells called photoreceptors that detect light and send signals to the brain, which then interprets them as images. The rest of the retina processes our side (peripheral) vision[iv].
Development of wet AMD
There are a number of layers that make up the retina.
In a healthy eye, blood vessels exist beneath a layer called Bruch’s membrane, providing oxygen and vital nutrients to the macula.
As the eye ages, debris from the next cell layer and surrounding tissues starts to accumulate, sometimes causing inflammation[v]. These inflammatory cells begin releasing vascular endothelial growth factor (VEGF) proteins which cause blood vessels to grow and leak fluid and blood in the back of the eye[vi]. This fluid and blood accumulates, damaging the photoreceptors required for vision[vi].
Most eye specialists agree that the best way to control these proteins is with an anti-VEGF treatment, a category of drugs designed to reduce new vessel growth and swelling[vii]. These types of treatments aim to help control fluid and stop blood vessels from leaking, and can help slow the progression of the disease[viii].
Monitoring wet AMD progression
While you can’t impact some of the risk factors for AMD such as your age or genetics, there are many ways you can help to delay the progression of your wet AMD. If you have been diagnosed with wet AMD, it is important to make the most of the time you get with your eye care team, so take this quick questionnaire and download your appointment guide.
"There are many ways you can help to delay the progression of your wet AMD."
Monitoring changes in your vision is important for ongoing and effective management of wet AMD. To monitor the progression of the disease, you might consider keeping track of your vision by using an Amsler grid, a simple black-and-white grid with a small black dot in the middle. The Amsler grid is one of the tools used to detect and track changes in vision caused by damage to the macula.
A healthy eye will usually see the lines as straight. To someone with dry or wet AMD the lines can suddenly appear wavy or blurry, or be blocked out by an empty gap or dark spots in the centre of the vision[ix].
You can order an Amsler grid by visiting macularsociety.org for more information or by calling 0300 3030 111.
If you are suspected of having wet AMD, your eye specialist will conduct an optical coherence tomography (OCT) scan. Similar to photography, OCT is a common non-invasive imaging technique that is used to detect fluid build-up in the eye[x]. By taking cross-sectional images of the retinal layers, an OCT scan will help your eye specialist to understand your disease progression and inform your subsequent treatment plan[x].
OCT image of eye with wet age-related macular degeneration
Image source: retinagallery.com
Wet AMD can cause severe vision loss over a short period of time if left untreated[xi]. Consistent treatment and regular monitoring of fluid and blood in the back of the eye could help slow down the progression of wet AMD. This along with lifestyle modifications could allow people living with the disease to remain independent for longer[xii].
In these exceptional times, hospitals and eye professionals are receiving regular guidance from The Royal College of Ophthalmologists as well as Public Health England to ensure everything possible is being done to make sure patients receive their eye injections in a safe environment.
For more information on how people living with wet AMD and their caregivers can manage the disease and track its progression, click here.