Intravitreal Injections for Retinal Disorders
There have been developments in treatments of some eye conditions including age related macular degeneration, retinal vein occlusion and diabetic retinopathy/maculopathy/macular oedema.
These new treatments involve an injection into the eye called intravitreal injections (IVIs).
Although these new treatments work in a significant proportion of patients, they do not always work in everybody.
These injections are an attempt to control the pathological process and try and stabilise the vision. In some patients the vision can actually improve.
It is important for you to remember that these injections are generally required regularly and are not a one-off injection. If for any reason the injections are stopped then the underlying eye pathological process will continue and it is likely the vision will deteriorate.
It is usually necessary to have three injections, one month apart, and then depending on the response the decision about the next injection can be made. On occasions injections may be required every month.
There are several types of intravitreal injections that we can use:
LUCENTIS (Ranibizumab)
This drug has been developed and licensed in the UK for treatment of age related macular degeneration, retinal vein occlusion and diabetic retinopathy/maculopathy/macular oedema.
EYLEA (Aflibercept)
This is a drug that also is licensed for age related macular degeneration, retinal vein occlusion, diabetic retinopathy/maculopathy/macular oedema. It may have a longer action than Ranibizumab in which case it may require fewer injections to help control the retinal condition.
AVASTIN (Bevacizumab)
This drug is licensed in the U.K. for several conditions but can be used “off label” for intravitreal injection for conditions such as age related macular degeneration, retinal vein occlusion and diabetic retinopathy/maculopathy/macular oedema.
We no longer offer Avastin intravitreal injections at The Lancashire Eye Clinic.
RISKS AND COMPLICATIONS OF INTRAVITREAL INJECTIONS
As with any treatments there are always risks and complications.
The following complications have been identified in the literature but these are rare and are mentioned for completeness of your informed consent:
Infectious Endophthalmitis
The incidence ranges from 0.02 – 1.6%
Endophthalmitis can cause permanent loss of vision and possible complete loss of vision in the eye.
Should you notice any sign of visual disturbance or ocular pain you should contact the clinic immediately.
Intraocular inflammation
Intraocular inflammation is one of the main ocular adverse events associated with IVI. This can range from 1.4 – 2.9%. This can cause significant loss of vision.
It is difficult to differentiate sterile intraocular inflammation from infectious endophthalmitis.
Rhegmatogenous retinal detachment
The incidence of rhegmatogenous retinal detachments after IVI is low (0 – 0.6%).
Retinal detachment can result in loss of vision and occasionally complete loss of vision.
Intraocular pressure elevation
This is common and can last a few hours at most.
In some patients repeated injections can cause a long term rise in intraocular pressure that may require treatment.
Ocular haemorrhage
Subconjunctival haemorrhage (redness) on the surface of the eye can occur in approximately 10% of injections and should resolve spontaneously.
Occasionally haemorrhage inside the eye may occur which may take weeks/months to resolve.
The incidence is higher if you are taking aspirin or Warfarin equivalents.
We do not recommend discontinuing your Warfarin prior to injection
Lens Damage
If the crystalline lens inside your eye is contacted by the needle then there will be lens damage and a cataract is likely to develop. This may require surgery in the short or long term.
It may be that the incidence of cataract is increased with the increasing numbers of injections that you have.
Tractional retinal detachment
This can occur following IVI in advanced diabetic retinopathy leading to loss of vision.
Retinal pigment epithelial tear in Age Related Macular Degeneration
The incidence ranges from 0.06 – 27%. – leading to sudden decrease in vision.
Systemic safety
Anti-VEGF agents are used widely with systemic administration for other non-ocular diseases.
There may however be an increased risk following IVI of myocardial infarction (heart attack), stroke, hypertension (high blood pressure), gastrointestinal perforation and kidney disease.
Rare ocular and systemic side effects
- Retinal vein occlusions – leading to reduced/loss of vision
- Retinal artery occlusions – leading to reduced/loss of vision
- Haemorrhagic macular infarction – leading to reduced/loss of vision
- Cranial nerve palsy
- Visual hallucinations
- Erectile dysfunction
- Decrease in kidney function
Intravitreal injections of anti-VEGF are the main stay for the treatment of many retinal diseases. Despite good results in halting disease and improving vision, intravitreal injection of anti-VEGF agents may be associated with devastating complications as listed above. These are rare.
Of course the alternative to this is not to have the injection in which case the disease process will proceed and almost inevitably cause further reduction in vision.
It is important that you keep any appointments for intravitreal injection as these are tailored to your specific need and timing. Any interruption in the time protocols may cause loss of vision.
THE PROCEDURE
For the intravitreal injection you will be lying down. We will put an elastic strap around your head to apply pressure to the eye for approximately five minutes. Your eye will be anaesthetised/numbed with drops. The eye will be cleaned with antiseptic. You will be asked to look in a certain direction and the injection performed.
The injection is not painful although you may feel a little pressure around the eye.
Once the injection is performed you will be escorted back to the waiting room and when you feel confident you will be able to leave the clinic.
After the injection your eye may be a little irritable, in which case you can use artificial tear drops to lubricate the eye. You do not generally require antibiotics afterwards.
For a few hours after the injection you may notice some floaters or fluid swirling around in your eye. This should settle within 24 hours.
On discharge you will be given a further date with probable retinal OCT scan.
If your eye becomes :
-Sticky
-Very red
-Painful
-You notice loss of vision
you should contact the clinic immediately.
