An intravitreal injection is an injection into the vitreous, which is the jelly like substance inside your eye. It is performed to place medicines inside the eye, near the retina.
Why is an intravitreal injection performed?
Intravitreal injections are used to deliver drugs to the retina and other structures in the back of the eye, thus avoiding effects on the rest of the body. Common conditions treated with intravitreal injections include diabetic retinopathy, macular degeneration, retinal vascular diseases and ocular inflammation.
What is the intravitreal injection procedure?
The procedure takes around 10 minutes. We will lie you or sit you back in a comfortable position in a reclining chair. Anaesthetic (numbing) drops will be placed in your eye and your eyelids will be cleaned with an antiseptic solution. Dr Isaacs will instruct you to look to the opposite side and will gently hold your eyelids apart with his fingers. You may feel a slight sensation of pressure in the eye as the injection is performed. Immediately afterwards you may be able to see a swirling sensation in your vision as the drug circulates in your eye. Occasionally the vision may be dimmed or dark for a minute or two immediately after the injection, but this will return to normal.
What can I expect after the procedure?
The eye may be irritated with heavy tearing for a day or two, then comfortable thereafter. You can
use lubricant eyedrops to reduce discomfort.
Mild redness of the eye can be expected for the first 24 hours.
A red blood spot may be present at the site of injection (on the "white" of the eye). This may enlarge with time, then gradually fade like a bruise.
For steroid injections (triamcinolone), new floaters are expected, since the steroid is made up of crystals. These clear rapidly, typically disappearing in 1-2 weeks.
Are there any risks?
Injecting any medication into the eye may result in increased intraocular pressure, inflammation, or more serious side-effects such as cataract formation, intraocular bleeding, damage to the retina (retinal detachment or tear) or other eye structures. These complications are rare, estimated at less than 1 per 1000 injections.
There is a remote possibility that you may develop an infection within your eye (endophthalmitis), which may lead to vision loss or, in rare cases, loss of the eye, but the risk of an infection is extremely low (estimated at 1-2 cases per 1000 injections).
What else do I need to know?
Please allow at least 1 hour for your appointment. This will allow dilation of your pupils, the injection, and review afterwards by your doctor. Before you leave, you will have another appointment made for review, depending on the type of injection you have received.
It is very important for you to tell us about any health conditions that you have, all the medications that you are taking, and especially any allergies to medications that you have had in the past.
Pregnancy is a contraindication to intravitreal anti-VEGF injections. You must inform us if there is any possibility you could be pregnant.
What are concerning symptoms after the procedure?
Call us immediately for:
Decrease in vision or distinct increase in "floaters" after the first 24 hours.
Increased or new pain, especially aching pain after the first 24 hours following injection.
Increased redness, swelling or discharge from eye, especially after the first 24 hours following injection.
Brief flashing lights visible in the peripheral (side) vision.
Dark shadow progressing toward the centre of your vision like a curtain.
New rash or hives.
How do I prepare for the procedure?
It is important to understand the reason for the injection and the potential risks of the
injection. If you have any questions ask Dr Isaacs.
Do not wear eye make up on the day of the procedure
Arrange for someone to drive you to and from your appointment.