What are intravitreal injections?
Intravitreal injections are used to administer drugs into the eye. The injection allows the required drugs to enter the vitreous cavity, a space situated at the back of the eye, behind the lens (as seen in the image).
What are they for? Which conditions are they used to treat?
Injecting drugs directly into the vitreous cavity is seen as the best way to treat certain eye conditions and protect vision.
Conditions treated in this way include:
-AMD (age related macular degeneration) a degenerative disease affecting the macula (the area at the centre of the retina) which causes loss of central vision.
-Macular edema (swelling at the centre of the retina).
-Infections and inflammation of the inner eye.
Why are they necessary?
Intravitreal injections are a far more effective way for drugs to reach and treat the centre of the eye than taking them orally or injecting them into a vein. Intravitreal injections allow for higher and more intense doses than would be safe to take orally.
What types of drug are injected in this way?
Intravitreal injections can be used to administer antibiotics to treat endoftalmitis (inflammation of the interior of the eye), a class of drugs known as antiVEGF for conditions including dry AMD and diabetic retinopathy, or corticosteroids (steroid hormones) for macula edema (swelling at the centre of the retina).
How are the injections administered?
The injections are administered in an operating theatre under topical anaesthetic. First the eye and eyelids are disinfected in sterile conditions. The procedure is normally quick and causes little discomfort afterwards.
Effects of the procedure
After the injection, you may have the sensation of having something in your eye, feel pressure or mild discomfort, although feeling pain is rare. You may also have slightly bloodshot eyes or see “floaters.” These effects will disappear with time.
It is important not to touch your eyes and to refrain from swimming for a few days.
If you experience pain, eye reddening or sensitivity to light or a reduction in vision then you should see the ophthalmologist immediately.
Although the risk of complications is extremely low, the most likely complication is infection. Nevertheless, preparing the eye in sterile conditions in the operating theatre means that this is very unlikely. Other less serious possible complications are equally rare.