Intravitreal Injection

In the last decade or so, the advent of several injectable medications into the eye has revolutionised the way we treat certain retinal conditions including ‘wet’ macular degeneration, diabetic maculopathy, retinal vein occlusion amongst others.

Prior to the availability of these medications, it was generally accepted that the central vision for many of these patients would progressively deteriorate. Now however, not only can patients maintain their level of vision recorded on initial presentation with the disease, many patients experience partial to full restoration of their vision from these injection treatments.

What are these medications?

These medications can be classified into 2 categories:

  • Anti- Vascular Endothelial Growth Factors (VEGF): These include Aflibercept (Eylea), Ranibizumab (Lucentis) and Bevacizumab (Avastin), used for wet macular degeneration, diabetic maculopathy and retinal vein occlusions.
  • Steroid depot: Dexamethasone (Ozurdex) and Triamcinolone, used in diabetic maculopathy, post-operative cystoid macular oedema and inflammatory eye diseases.

How are these medication given?

These medications are injected into a large cavity in the middle of the eye which is normally filled with a jelly-like structure called the vitreous humor through a very fine needle. The medication stays in the vitreous cavity at a relatively high concentration for a while and exerts its effects on the diseased retina. Depending on the disease being treated, which particular drug is used and each eye’s varying response to the medication the frequency and duration of the treatment may differ. Taking ‘wet’ macular degeneration as an example, generally treatment starts with an injection every 4 weeks until the bleeding and leakage of the abnormal choroidal blood vessels improves (read more about macular degeneration here). After that, the interval between injections may gradually lengthen out. Usually, most patients with ‘wet’ macular degeneration can be maintained on 2-3 monthly injection intervals. Some however, with aggressive disease may require more frequent maintenance dosing indefinitely.

Does it hurt?

In short, no. At Applecross Eye Clinic, we anaesthetise the eye by instilling several doses of anaesthetising drops as well as a localised anaesthetic block (which itself is also pain-free) to make sure the eye is well numbed.  As such, it is very rare for anyone to feel pain during the intravitreal injection. In fact, many patients do not feel the injection being given at all. Occasionally, minor discomfort / pressure may be felt. But even then, it is generally very well tolerated.

What happens after the injection?

Patients are allowed to leave the clinic straight after the injection and some may prefer to have a pad over the eye for an hour or so. The vision may be slightly blurry for the rest of the day and may also be quite light sensitive. As such, patients should not drive straight after the injection, and we recommend taking the day off work. The eye may also feel gritty and dry for 24 hours and it is common to have minor bleeding around the injection site which will spontaneously dissipate over several days.

Are there any potential complications?

Unfortunately, no medical procedures are completely ‘risk-free’. However, Intravitreal injections are generally considered quite safe. Severe complications are rare and include: infection, retinal detachment, cataract.

It is rare to lose vision as a result of an intravitreal injection. But if you do develop severe pain, redness or progressive loss of vision after an intravitreal injection at AEC, please call our clinic or your nearest major hospital immediately.