Trabeculectomy (glaucoma surgery)

Glaucoma is the name for a group of eye conditions which cause damage to the optic nerve at the back of the eye. The naturally made fluid in the eye is unable to drain away properly which can result in a build up of pressure within the eye. The pressure is usually treated with eye drops. If the eye drops fail to reduce the pressure, damage to the optic nerve will cause permanent loss of sight. To lower the eye pressure a surgical procedure known as a trabeculectomy can be carried out.

Trabeculectomy

A small opening is made in the white part of the eye near the upper eyelid to form a drainage channel. The opening allows the eye fluid to drain away to a reservoir known as a filtering bleb and reduce the eye pressure. The bleb is formed during surgery from the normal covering of the eye. The bleb will have the appearance of a blister-like bump on the white of the eye, usually under the upper eyelid. A strong anti-scarring drug (Mitomycin C) may be used to improve the success of the operation.

A trabeculectomy can take up to an hour and can be carried out either under a local or general anaesthetic. The doctor will discuss which option is most suited to you.

After a successful trabeculectomy it may be possible to reduce glaucoma eye drops. If the trabeculectomy is not successful the operation may need to be repeated or further treatment may be required. The aim of the operation is to reduce the risk of further damage to the optic nerve. It will not improve your sight, but will hopefully help protect your vision in the longer term.

What are the risks?

Some of the risks involved are:

• Bleeding
• Infection
• Inflammation
• For a period of time pressure in the eye may become too high or too low.
• In some cases a cataract may develop. This can be treated by an operation if necessary.
• Serious complications are rare, but very occasionally the sight can get worse after the trabeculectomy and not recover.

Before the operation

If you are taking warfarin tablets please discuss the dose with the doctor.

Please take all other medication as normal or as instructed. Your doctor will advise you on which eye drops to use after surgery.

After the operation

• Your sight will often be blurred immediately after the operation. This will usually improve after a week or two, but can last up to six weeks.
• Your eye will be watery for a short period of time.
• You may have a gritty sensation in the eye for a week or two.
• Mild pain can be relieved by taking pain killers such as paracetamol.
• You will be given new eye drops to reduce scarring at the operation site. These usually need to be taken every hour initially but the frequency will be explained to you by your doctor. If you are on more than one eye drop wait five minutes between applications of the different eye drops. You must follow the detailed instructions given to you.
• You will be seen regularly in the Glaucoma clinic to monitor your eye’s recovery.
• In some cases you may require an injection to prevent scar tissue forming which can block the drainage channel. This can be given in the outpatient clinic.
• The stitches may also need to be adjusted or removed.
• Following the operation you should rest and take things easy but will be able to carry out normal day to day activities.
• Wear sun glasses if the light is too bright for comfort. If you wear contact lenses you should discuss this with your doctor. If you wear glasses your prescription may need to be changed following surgery, your doctor will advise you.
• You should not rub your eye, undertake strenuous exercise or heavy gardening and avoid coughing and sneezing if possible.
• Your doctor will advise you when you will be able to drive and return to work.

If you experience any of the following:

• Severe pain
• Sudden loss of sight
• Discharge

You need to contact the hospital via telephone on:

• 01223 217778 (Emergency Eye Department) or 01223 274889 (Specialist Glaucoma Nurses) between 08:30 and 17:00 hours

or

• 01223 256336 (ward M5) after 17:00 hours.