Intravitreal injection
You can find a printable pdf copy of this information sheet here.
Many macular conditions are best treated by putting a small amount of medicine within the eyeball in the vitreous cavity. This is called an intravitreal injection and is a standard, office-based treatment.
Common conditions treated with intravitreal injections
Age-related macular degeneration (AMD)
This is a common macular condition associated with age, although environmental factors (smoking, diet) and genetics also play a role in its development. In some patients with AMD, new blood vessels can form at the macula, resulting in leakage of fluid and blood into the neurosensory retina. This is called neovascular AMD (nAMD) or wet AMD.
Injection with anti-vascular endothelial growth factor (anti-VEGF, such as Avastin or Eylea) is the only way to control the disease process and stop the deterioration of vision. Without treatment, most patients will develop significant vision loss over the course of a year, and with treatment, there is an average of 1-2 line improvement in visual acuity (see MARINA and ANCHOR trials).
Diabetic retinopathy and maculopathy
For patients with diabetic eye changes, intravitreal anti-VEGF or steroid injections are used to control the amount of swelling associated with blood vessel damage in the macula. Furthermore, intravitreal anti-VEGF injections can be used to treat peripheral diabetic retinopathy, such as in the case of proliferative diabetic retinopathy, to stop the formation of abnormal new vessels.
Retinal vein occlusion
Similar to diabetic eye disease, intravitreal injections are used to control the amount of macular swelling or to treat the presence of abnormal peripheral blood vessels.
Myopic neovascularisation
This is a condition where moderately to severely short-sighted (myopic) patients develop abnormal new blood vessels at the macula, resulting in sudden and significant vision loss. Injections with anti-VEGF are very effective in controlling this condition, and most patients only require 1-2 injections to reach stability.
Types of medications delivered by intravitreal injections
Anti-vascular endothelial growth factor (anti-VEGF)
This type of medication is called monoclonal antibody, and in anti-VEGF, the antibody specifically binds to a molecule that causes blood vessels to form and become leaky. These medications include Avastin (Bevacizumab), Eylea (Aflibercept), Zaltrap (Ziv-aflibercept), Lucentis (Ranibizumab) and Vabysmo (Faricimab).
Steroid
Steroid is traditionally used as an anti-inflammatory medication. Within the eye, intravitreal triamcinolone injection can reduce the amount of swelling at the macula in patients with retinal vascular disorders (such as diabetic eye disease or retinal vein occlusion). However, steroid injection is associated with a higher incidence of side effects, including cataract formation, sterile inflammation or raised intraocular pressure. As a result, this is usually our second-line treatment for retinal disorders.
Dr Leo Sheck will discuss the best medication for your condition, considering your clinical situation, funding and preferences.
How is an intravitreal injection performed?
Dr Leo Sheck is an expert in intravitreal injections, and he will guide you through the entire process and ensure you are comfortable. You will be lying on a reclining chair, and Dr Sheck will numb your eye completely using anaesthetic drops. Some patients may prefer a small anaesthetic injection. The eye will be sterilised, and then you will feel a slight pressure around the eye - which is when the injection happens. The actual injection only takes a few seconds and is very well tolerated.
How do I prepare for an intravitreal injection?
You must inform Dr Sheck if you have any infection anywhere in the body or are on antibiotics. Dr Sheck should also be told if you have had a recent stroke or heart attack (within three months). Otherwise, keep the eye clean and wear no eye makeup on the day of the injection.
Any precautions after an intravitreal injection?
You must keep the eye clean and avoid getting anything into the eye for the first 48 hours. So when showering, you must be careful that water does not enter the eye. Please refrain from gardening or DIY activity for 48 hours, and do not swim for five days. If you are a contact lens wearer, do not wear your lens for five days.
Otherwise, use the lubricating drops up to every hour after your injection for the first day to protect your cornea.
Side effects and risks
The eye can often be gritty for 24 hours, and the injection site can be red (like a small patch of blood). These are entirely harmless and will settle over days.
More serious is that there is a small risk of infection inside the eyeball from the injection (around 1 in 5000), bleeding inside the eyeball (again around 1 in 5000), or retinal detachment (less than 1 in 10000). You need to contact Dr Sheck and his clinic immediately if the eye is very painful or your vision drops off.
Every medical procedure is associated with some risk, and Dr Sheck will only recommend this procedure if the benefits outweigh the risks.
About Dr Leo Sheck
Dr Sheck is a RANZCO-qualified, internationally trained ophthalmologist. He combined his initial training in New Zealand with a two-year advanced fellowship in Moorfield Eye Hospital, London. He also holds a Doctorate in Ocular Genetics from the University of Auckland and a Master of Business Administration from the University of Cambridge. He specialises in medical retina diseases (injection therapy), cataract surgery, ocular genetics, uveitis and electrodiagnostics.
