In the middle of the eye is a large cavity which is filled with a jelly-like substance called the vitreous humour. An intravitreal injection is an injection of medicine into the jelly. This is the most effective way of getting high concentrations of medicine into the eye.
There are several different eye diseases that are treated in this way including:
Many different types of medicines can be injected into the vitreous. Examples include:
Without treatment, patients with wet macular degeneration have an extremely high chance of losing vision. Research has shown that patients who are regularly treated with either aflibercept, lucentis or bevacizumab injections into the eye maintain (or sometimes gain) vision.
These medications stop the leakage and haemorrhage associated with the growth of the abnormal blood vessel, which is the primary cause of 'wet' macular degeneration.
For patients with wet macular degeneration, treatment is required every 4 weeks until the macular degeneration is brought under control. Then, the treatment interval may be slowly increased. Usually patients are able to be maintained on treatment every 8-12 weeks. Occasionally patients with particularly aggressive disease, or if they are being treated in their only good eye, will need treatment more frequently.
This depends on the disease which is being treated. For wet macular degeneration, it is most likely that you will be treated forever. If treatment is ceased, it is possible that you will have recurrence of the wet macular degeneration, which can result in severe haemorrhage resulting in permanent loss of vision.
In some other diseases, treatment may be ceased after 1-2 years in some cases.
Researchers are currently investigating medications that last longer in the eye, reducing the burden of treatment in the future.
You shouldn't feel any pain during the injection, but you may feel some pressure. The vast majority of patients tolerate the injections very well.
At Northern Eye Surgeons, our procedure is to use local anaesthetic drops as well as a local anaesthetic injection. The anaesthetic injection doesn't hurt as the skin has already been numbed by the drops.
You can leave straight away, but as you will have a pad on your eye for 1 hour, we recommend that you have someone to take you home. It is common to have a gritty eye for up to 24 hours after the injection and some bleeding around the injection site. Your vision will be slightly blurry, so we recommend that you don't go to work after your injection.
Intravitreal injections are considered safe procedures, however as with all procedures there are some risks.
Severe complications are rare, and include:
It is rare to lose vision as a result of an intravitreal injection. But if you do develop severe pain, redness or blurred vision, then we recommend that you call our clinic or your nearest major hospital immediately.
Currently there is some debate as to whether there is an increased risk of cerebrovascular disease in patients having anti-VEGF injections. Please speak with your doctor if you are concerned about this.