St Paul’s Eye Clinic
Royal Liverpool University Hospital
Royal Liverpool University Hospital
Fairfield Independent
Hospital
Hospital
Minimally invasive glaucoma surgery or MIGs, is an umbrella term we use for an operation that is shorter and a smaller operation than a traditional glaucoma operation.
Glaucoma is a condition of the eye where increased pressure within the eye causes damage to the nerve that allows you to see (optic nerve). This can then lead to some loss of vision. You may not know that you have glaucoma until you have lost a lot of your sight, as there are usually no known early warning symptoms.
The way to treat glaucoma is to lower the pressure within the eye and this can be achieved either with medication in the form of drops or tablets, or with laser or surgery. Unfortunately, these treatments cannot restore vision that has already been lost. The aim of treatment is to reduce the pressure in the eye to prevent or slow down further damage to the optic nerve and so protect your vision from getting worse.
One of these minimally invasive glaucoma procedures has been chosen for you as other options to the lower pressure and therefore stabilise your glaucoma have not been successful enough.
Minimally invasive glaucoma surgery or MIGs, is an umbrella term we use for an operation that is shorter and a smaller operation than a traditional glaucoma operation. They are typically reserved for when the glaucoma condition is not quite so advanced and can often be done in combination with cataract surgery.
These minimally invasive glaucoma operations are designed to bypass an area of the eye where there is resistance to the natural drainage of the fluid in the eye. By bypassing this area, the hope is that the eye pressure reduces and therefore prevents or slows down further damage to the optic nerve. It will not cure your glaucoma and will not help with any existing visual problems. However, by lowering the pressure, it helps to prevent any further vision loss. It will hopefully allow the pressure in the eye to be lower, without the need for eyedrops.
There are many different types of MIGs and your team will decide which is the best for your care.
The operation is usually performed under a local anaesthetic, meaning that you are awake but your eye is numb so you will not feel anything. Your eye will be numbed with eye drops and then a small injection will be given around your eye. The injection may cause a pressure sensation and brief discomfort. The local anaesthetic takes several hours to wear off and may affect your vision during this time. The surgery takes approximately 10 to 15 minutes.
It may be decided to combine this procedure with cataract surgery. Please see the cataract surgery leaflet for further information about this procedure.
Please continue to use any eye drops and tablets for your glaucoma as prescribed, unless directed otherwise by your ophthalmologist.
If you take any blood thinning medication (e.g. Warfarin) or have had bleeding problems in the past please discuss this with your ophthalmologist before surgery.
Before your operation you will be asked to attend a pre-operative assessment appointment to check you are fit for the procedure and anaesthetic.
You can go home when you feel ready. Your eye will be covered by a protective plastic shield and a patch which you can take off the morning after surgery. You do not need to put drops in your eye until after the shield has been taken off.
The morning after your operation you can take the shield off and gently bathe the eye with the solution provided by the nurse. You can then start the post-operative drops.
You may need to be seen the day after the surgery. You will be given a follow up appointment after your surgery.
If you are using drops in the other eye you should continue to do so unless told otherwise.
You may be advised to stop your glaucoma drops on the day of the surgery to the operated eye, but frequently you will be asked to continue them. You shall be informed after the operation if you should stop or continue these drops.
You will need to use two different drops in your operated eye to help it recover from the surgery. These are an antibiotic and a steroid drop. You will usually be on these for about 4 weeks after the surgery but it may be up to 3 months depending on which procedure you have done.
Studies have shown that these procedures lower the eye pressure in a significant number of patients when used in combination with cataract surgery. Often these patients require less eye drops to achieve this and sometimes patients require no drops after surgery. These procedures are all relatively new and so long-term data to demonstrate how long this effect lasts for is limited.
There are three ways to lower the pressure inside the eye on a long-term basis: eye drops, lasers and surgery.
You may already be using eye drops, but they did not lower the eye pressure enough, you are getting side-effects, or you find it difficult to use the drops. The surgery is used when eye drops and lasers have not worked or are not suitable.
Serious complications are uncommon and as mentioned above, serious complications of these procedures are lower than other alternative surgical options.
You could have a small amount of bleeding inside your eye. If this happens, your vision could be blurred for a few weeks. The eye could become inflamed, which is why you will be given steroid drops after surgery.
The procedure may not be as effective as hoped and therefore the pressure in the eye may remain high after the procedure. If so, you may well require eye drops to lower the pressure or a further procedure. The procedure may be effective early on but this effect may reduce over time. We do not have enough data to suggest the likelihood of this, however again this may be treated with eye drops or another procedure.
Sometimes the eye pressure may be too low after the surgery and if that happens, you may require further surgery to fix this but the risk of this is very low.
As with any operation in the eye, there is a very low risk of infection in the eye.
Any of the above risks can lead to reduced or loss of vision or further surgery. However, these risks are very low.
You may be suitable for a laser procedure, or you may need more eye drops. However, this may not control your Glaucoma and your vision may continue to get worse.
If you are diagnosed with glaucoma and you drive then please be advised that it is mandatory to contact DVLA medical notifications. Contact details are: telephone: 0300 790 6806, email glaucomaqueries@dvla.gov.uk and website information www.gov.uk/glaucoma-and-driving. As a driver, it is your responsibility to inform the DVLA. You must also inform your car insurance company of your eye condition.
