Dr Amy Cohn Ophthalmic Surgeon

The back of the eye consists of a highly specialised neural tissue called the retina. This is responsible for turning what we see in our environment into electrical impulses that are transmitted to our brains.

The centre of the retina is the macula. The macular is responsible for fine visual tasks such as reading, writing, driving and face recognition.

Age-related macular degeneration (AMD) is a degenerative condition that usual affects people over the age of 60 and causes a reduction in central vision. It is one of the leading causes of blindness in our community.

There are two types of AMD but both may occur in the same eye. These are known as Wet AMD and Dry AMD.

Dry AMD has many stages. The earliest is when waste products that are normally cleared by the retina begin to accumulate. These are called drusen. Other dry changes include retinal pigment epithelial changes and Geographic Atrophy (GA).

GA represents end-stage AMD and can cause significant visual loss. Currently there is no treatment for GA.

Wet AMD occurs when abnormal blood vessels grow beneath the retina. These vessels leak blood and fluid into the retina causing reduced vision. In the last decade treatment for wet AMD has been revolutionised by a new therapy known as Anti-VEGF (Anti-vascular endothelial growth factor) injections.

There is some evidence that taking a dietary supplement may slow the progression of the disease in some specific patients. Dr Cohn can discuss if this is right for you.

There are some basic things that are thought to prevent the progression of AMD:

• Do not smoke – studies have shown that AMD is more severe and progresses more rapidly in smokers.
• Eat deep sea fish rich in omega 3 regularly (up to 3 times per week).
• Have a diet that is rich in green leafy vegetables that contain Lutein (such as spinach, curly kale and broccoli). Other healthy fruit and vegetables include ones with Vitamin C and Zeaxanthin such as corn, papaya and capsicum.
• Anti-oxidants such as those found in blueberries, red kidney beans and green tea are thought to be beneficial.
• Limit saturated fats.
• There is some evidence that taking a dietary supplement slow progression of disease in some patients.

You may be told you have signs of early AMD at a routine Optometry review. Often at this stage you will not have noticed a change in your vision and you can be monitored regularly without treatment.

Alternatively, you may experience central distortion or loss of vision. Your Optometrist or Ophthalmologist will then perform a detailed examination to diagnose the problem. This includes measuring your vision and dilating your pupils to examine the retina. Patients should not drive after their pupils have been dilated for four hours.

It maybe necessary to perform extra tests to diagnose AMD. These include:

• Optical Coherence Tomography (OCT): This is a scan or photo of the macular used to diagnose AMD and follow up treatment. It gives the thickness of the macular and allows microscopic detail of the retina to be pictured.
• Fluorescein angiography (FA): This involves injecting dye into a vein in your hand or arm and taking a series of photographs over 10 minutes to see whether abnormal blood vessels from AMD are growing.
• Indocyanine Green (ICG): Another dye test used for diagnosing sub-types of AMD such as Idiopahtic Polypoidal Choroidopathy and other retinal conditions like Central Serous Chorio-retinopathy.

Anti-VEGF treatment: Wet AMD can now be treated with anti-VEGF drugs including Lucentis® (ranibizumab), Eylea® (aflibercept) and Avastin® (bevacizumab). These are anti-bodies that block VEGF and therefore temporarily slow the growth of the blood vessels. Lucentis and Eylea are licensed in Australia for the treatment of AMD.

There is a new drug which may be approved for wet AMD in Australia shortly called Beovu (Brolucizumab).

Dr Cohn will discuss the most appropriate treatment for you.

The drugs are all intra-vitreal injections that are safely injected into the back of the eye in the doctor’s rooms or day surgery. Millions of injections have been performed world wide to date with excellent results.

Studies have shown that the majority of patients with regular injections maintain their vision (that is the vision they presented to the doctor with) and up to one third of patients improve vision. A small percentage of patients continue to lose vision despite treatment. This may be due to ongoing dry AMD which cannot be treated currently. The goal of anti-VEGF treatment is to prevent further visual loss.

The drugs have a duration of action of between 4 and 16 weeks and therefore treatment needs to be repeated. Almost all patients require ongoing treatment indefinitely to prevent further visual loss.