Lucentis Injection for Wet Age Related Macular Degeneration
Wet Age Related Macular Degeneration (ARMD) is a medical condition which causes damage to the centre of your vision. Without treatment there is a 60% chance of significant visual loss in the affected eye within 2 years. There is approximately 6%-10% chance of the other eye being affected with wet age related macular degeneration each year. It is not known why some people get it and others don’t but it is more common the older you are and smokers are at particularly high risk of visual loss.
What is going wrong with my eye?
An abnormal clump of blood vessels has started to grow in the wrong place forming a lump underneath the retina. The retina is a bit like wallpaper lining the inside of the eyeball. It is made up of light sensitive cells which are very delicate and easily damaged. The retina is essential for normal vision. The clump of abnormal blood vessels leak under the retina, this sometimes creates a blister of fluid. This causes the early symptoms of distortion of straight lines when you look directly at them. Untreated the leakage gets worse and the blood vessels start to bleed and form a lump of scar tissue, or sometimes the blister bursts. Both these mechanisms contribute to permanent loss of central vision.
How might my vision be affected?
In the early stages you may notice that straight lines look bent or distorted. In the later stages there may be a black patch over the centre of your vision which you cannot see through. The condition will only affect the centre of your vision but this is the important part of your vision for reading, watching TV, recognising faces and doing any sort of detailed visual task like knitting.
How do Lucentis injections work?
Lucentis is an anti-VEGF agent (anti vascular endothelial derived growth factor). This means that it acts as a chemical signal to the clump of abnormal blood vessels behind the retina to shut down the leak. Although it does not work in every patient it is extremely effective. 70% of patients maintain the vision which they had when they started treatment over a two year period. 30% of patients improve vision quite dramatically (they see 3 more lines on the eye test chart).
How is the Lucentis injection given?
To reach the clump of abnormal blood vessels the Lucentis has to be injected into the eyeball. This is done in a clean room or operating theatre. Your eye will be numbed with a drop of anaesthetic and the pupil will be dilated with another eye drop. You lie down on a trolley and we put an iodine solution on the surface of your eye to kill off any bacteria. Antibiotic eye drops are also used to keep the eye as sterile as possible before the injection. A sterile drape is stuck over the eye and a clip is used to keep your eyelids open during the injection. The injection passes through the white bit of the eye so you shouldn’t see the needle coming towards you. Although you can feel some sensation it is well tolerated and similar to a blood test in terms of discomfort. After the injection we will test your vision, you will then be seen by the nurse who will check that you are well enough to go home and make sure you have some antibiotic drops (Chloramphenicol) to use 4 times per day for 5 days.
Are there any side effects or risks of the injection?
Common side effects include mild blurring of vision for a day or so after the injection. Often a small blood vessel on the outside surface of the eye is burst during the injection. This makes the white bit of the eye look bright red but it is not painful and gets better without any treatment within a week or so. The eye may feel gritty for a day or so after the injection. Occasionally following the injection there may be transient air bubbles inside the eye which look like small black circles, these are nothing to worry about and will disperse on their own within a couple of days.’
Serious side effects include infection which occurs at a rate of about 1 per 1000 injections. Infection inside the eye often leads to blindness so we take extensive precautions to avoid this happening. Infection causes a painful (severe ache), red eye with rapid reduction in vision.
How many injections will I need?
Unfortunately the injections seem to wear off after a few weeks to months and therefore need to be repeated. Current practice is to give everyone one injection every month for the first three months and then to only give more injections if there is still evidence of leaking blood vessels at the back of the eye. These indications for re-treatment will probably change as more research studies are done using Lucentis. In practice most patients will require 8 injections in the first year of treatment and 6 in the second year. Some patients will stabilise and not need further injections whilst others will still need an injection every month even after two years.