Anti-VEGF agents: indications and current options

Anti-VEGF agents are used in order to treat a number of eye conditions. Highly regarded consultant opthalmologist Mr Hadi Zambarakji explains everything you need to know about these agents, including the differences between each anti-VEGF agent, how they are injected and associated complications.

What is Vascular Endothelial Growth Factor? (VEGF)?

VEGF (vascular endotelial growth factor) is a vascular permeability factor. In other words, it’s a protein, which is produced by many cells which stimulate the formation of blood vessels.

VEGF is a sub family of growth factors.

What are the most common indications for Anti-VEGF injections?

In ophthalmology, we use anti-VEGF injections to treat a number of conditions, which include macular degeneration, diabetic macular oedema and anti-ocular illusions.

In other circumstances, we use anti-VEGF injections for the treatment of rubeosis or eye neovascularisation, macular oedema from other causes and other conditions such as central serous chorioretinopathy occasionally will need treatment with anti VEGF injections.

Macular oedema after cataract surgery can occasionally benefit from anti-VEGF injections as well.

However, the main conditions are macular degeneration, diabetic macular oedema and ocular vein occlusion.

Where is the anti-VEGF agent injected?

These injections are administered into the vitreous cavity of the eye. It is the cavity behind the lens and in front of the retina. This is a large cavity of the eye which is full of vitreous gel. By injecting these substances into the vitreous cavity, it has access to the retina, where the disease is located.

How do various Anti-VEGF injections differ?

There are a number of anti-VEGF agents available which essentially differ in the size of the molecule, as well as in the number of growth factors they inhibit.

Broadly speaking, there have been a number of studies that have tried to compare one anti-VEGF agent to another. However, from a practical point of view, for the patient, what really matters is how effective the drug is and how long it works for.

What the patient wants is to be able to have the disease controlled with the fewest injections possible.

Practically speaking, this is what we end up juggling in the practical sense in the clinic, in order for us to treat the patient and to maintain vision and macular leakage.

What can a patient expect after an Anti-VEGF injection?

At the time of the injection, we cleanse the eye before we start, which involves the use of Betadine, an iodine-based solution. This causes some degree of irritation to the eye.

Quite invariably, after the first 12-24 hours, the patient’s eyes are a little red and sore. In some cases, there will be more discomfort than others. In some cases, people may develop a degree of iodine or Betadine sensitivity, therefore the discomfort may last a bit longer than usual. However, usually after the first 24 hours, the discomfort will settle and the patient can resume normal activities.

The main warning that we give patients is that they should report any sudden onset of severe pain or loss of vision in the eye after the injection.

What are the possible complications of anti-VEGF treatments?

The most common side effects of anti-VEGF injections are ocular discomfort and ocular redness and irritation, which are often relieved by use of optical lubricants including any particular dose which are based on sodium hyaluronate. Patients have said that this is one of the bestlubricants to use to keep the eye comfortable after injections.

Other side effects include retinal attachment and retinal tears which fortunately are quite rare. Additionally, some patients may suffer from infection or endophthalmitis. This is a devastating complication of injections. It can lead to an infection inside the eye which can affect the vision dramatically in the long term if it did happen.

Finally, we need to bear in mind that there is a small risk of elevated ocular pressure after injections and ocular inflammation. Both can blur the vision and also cause ocular discomfort and therefore should be treated appropriately.  

If you would like to know more about anti-VEGF injections, do not hesitate to book a consultation with Mr Zambarakji, do not hesitate to do so by visiting his Top Doctors profile today.