Macular degeneration, also known as age-related macular degeneration (AMD), is responsible for 50% of legal blindness cases in Australia. It is estimated that one in seven Australians over 50 years of age show signs of macular degeneration. 1.29 million Australians currently live with macular degeneration and a staggering 8 million Australians are at risk of developing this sight-threatening condition. These figures are projected to increase due to an ageing population.
There are two types of macular degeneration commonly referred to as “wet” or “dry”, but in more recent times macular degeneration has been classified based on stages: “early”, “intermediate” or “late” according to the clinical signs present.
There are different stages of macular degeneration:
Early stage: Vision is usually normal and some drusen, pigment changes and clumping are noted at the macula (central part of the retina used for detailed vision such as reading).
- Dry type: This type of macular degeneration does not leak and generally is the better type to have. The vision may decline at a slow rate causing loss of reading vision and central vision. There is no specific treatment apart from antioxidant vitamins.
- Wet type: The wet type of macular degeneration is due to abnormal blood vessels (called choroidal new vessels) growing at the macula. This causes leakage and bleeding under the retina, which can occur quite rapidly. This may lead to rapid loss of vision and blindness.
In both types of macular degeneration, central vision is compromised but the peripheral vision is usually not affected.
Intravitreal anti-vascular endothelial growth factor (VEGF) agents such as Eylea (aflibercept), Lucentis (ranibizumab), Avastin (bevacizumab), and more recently Beovu (brolucizumab) are highly effective in preserving vision and have shown significant success in treating age-related macular degeneration. These drugs are useful in the wet form of macular degeneration and they act by inhibiting the growth of abnormal blood vessels and help prevent leakage of these blood vessels.
Current research has found these drugs to be well tolerated as an intravitreal injection. Current data have demonstrated that up to 70% of patients show improvement in vision and also a slower disease progression.
Injection of these drugs is performed as an outpatient procedure. Topical, local and peribulbar anaesthetic is used and therefore the injection should have minimal pain. Patients who have anxiety can be managed with sedation in a day surgery setting. Patients are discharged on the same day and may go home with wearing sunglasses or a patch on their eye. This is removed after approximately three hours and antibiotic eye drops such as Chlorsig are administered four times a day for three days to help prevent infection.
Patients need to be aware that in the first day or so they may feel some irritation from the injection, as well as tearing and redness in the eye. They should notify City Eye Centre if they notice any persistent pain, signs of infection or severe loss of vision. Generally, the side effects of these drugs are rare but they may include intraocular infection, which can cause loss of vision and requires urgent treatment. Other rare complications include lens damage, retinal detachment and very rarely blood pressure rise, and cardiovascular problems.
Up to 70% of patients notice some improvement after their first injection. Most patients require injections performed monthly for the first three months and OCT scans to monitor the progression and response to treatment. Following this the interval between treatments may gradually be increased up to two months. Further treat and extend may be possible with some patients stable on 3 monthly treatment intervals of treatment. Treatment will be tailored by your Doctor according to the response to the treatment plan.
Use of antioxidant vitamins, which contain zinc, vitamin C & E, lutein and zeaxanthin such as Macuvision Plus, Bioglan Multi Plus Vision, Macutec, and MD Eyes has been reported to be useful in reducing the progression of macular degeneration by reducing oxidation damage to the retinal cells. The usual dosage is one tablet per day. A diet including fish high in omega-3 and omega-6, green vegetables and nuts are beneficial. Use of margarine, cooking oils (except olive oil) and processed food should be avoided. Smoking has also shown increased risk of macular degeneration progression and should be ceased.