Macular Degeneration

Problems and issues with vision can be worrying, often causing stress and anxiety for the patient concerned. However, constant advances in medical technology mean gradually more eye conditions can be treated.

What is AMD?

Age-related macular degeneration (AMD) comes in two forms: dry AMD and wet AMD. They are both painless eye conditions that affect the patient’s central vision; this usually happens gradually but in some cases vision is rapidly impaired.

The macula is responsible for central vision and is situated at the back of the eye. When the macula deteriorates, it will not function as it should. This can cause blurred vision, blind spots, colours being less vibrant and difficulty in recognising faces. The condition usually affects both eyes but they may not deteriorate at the same rate.

In dry AMD, waste products (drusen) build up and damage the cells of the macular. This is the most common form of AMD and vision loss is gradual. Approximately 9 out of 10 patients with AMD will be diagnosed with ‘dry’, however 10% of those could possibly go on to develop wet AMD.

Wet AMD, also referred to as neovascular AMD, develops when abnormal blood vessels damage the cells under the macula. Vision can deteriorate rapidly, making it a serious condition and medical advice should be sought immediately.

Both conditions are more likely to develop past the age of 50, are more common in women than in men and those of Caucasian and Chinese ethnicity.

Available Treatments

Whilst there is no cure for the condition, new advances in surgical procedures are helping combat the deterioration of vision which occurs with both types of AMD.

Anti-VEGF

An existing non-laser treatment has been used for some time for wet AMD and this takes the form of an injection into the eye itself. This is known as Anti-VEGF treatment (anti-vascular endothelial growth factor) and works by stopping blood vessels behind the macular growing and leaking into its cells, which, in turn, prevents further damage occurring.

The Anti-VEGF gel treatment is injected into the vitreous after anaesthetic eye drops are administered to numb the eye. A few hours after treatment the eye will feel a little sore as the drops start wearing off.

This procedure is repeated on three separate occasions, usually at monthly intervals, to assess if the treatment is working. Although the NHS will generally provide these injections free of charge, not all available Anti-VEGF medicine will be suitable for all patients. Some gels can cost around £9,000 for a two year course.

Photodynamic Therapy

Laser eye surgery is also available for patients with wet AMD. The procedure, called photodynamic therapy (PDT), involves injecting a light sensitive medicine into the patient’s arm (verteporfin). The medicine, once in the system, will attach itself to the abnormal blood vessels behind the macula. A low powered laser is then shone into the eye and the laser’s light activates the medicine. This, in turn, destroys the damaged blood vessels which will stop them leaking fluid or blood. Around 1 in 5 wet AMD patients will be suitable for this surgery.

Laser Photocoagulation

Around 1 in 7 patients are suitable for laser photocoagulation. This is due to the positioning of the abnormal blood vessels and surgery is not possible if they are situated near to the fovea. Using a local anaesthetic and a powerful laser, sections of the retina are burnt to prevent blood vessels moving into the macula. A side effects of laser photocoagulation can be a permanent grey patch within a patient’s field of vision but this may be better than before surgery.

Costs for these laser treatments vary according to the condition of the eye.

CentraSight

For patients with end-stage wet and dry AMD (the most advanced stage of the disease) a recently released procedure known as CentraSight can be used. This involves a tiny telescope being surgically implanted into one eye, providing central vision. The other eye keeps its peripheral vision and the two eyes work together to give enhanced sight. 20/20 vision will not return and the patient will have to cease driving, although near and distance vision may improve along with a quality of life and sight. The surgery is irreversible and costs around £20,000.

Reducing the Risks

AMD is a progressive disease which left untreated could eventually lead to blindness. You can reduce the risk of AMD getting worse by giving up smoking, eating a healthy diet and maintaining a healthy weight. You would also be advised to moderate your intake of alcohol and should wear UV sunglasses when outside.

Seek the advice of an experienced ophthalmologist if you are concerned in any way about vision loss.

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