The retina is a thin layer of nerve cells lining the inside of the back of the eye. You need the retina to see properly. It turns the light that enters the eye into an image by sending a message along the optic nerve to the brain.
When this light-sensitive layer becomes separated from the inner wall of the eye, it is called retinal detachment. If this is not treated, it usually leads to blindness in the affected eye.
Retinal detachment normally occurs in one eye.
Retinal detachment is rare, affecting one in 10,000 people. It can affect anyone but is more common in the following people:
The retina usually becomes detached if there are one or more holes in it. This can happen naturally if the retina becomes thin, particularly among those who are short-sighted. Retinal detachment can be caused by injury to the eye or diabetes (see Causes, above).
The fluid in front of the retina creeps in through the breaks and separates the retina.
Retinal detachment can be treated with surgery to seal the holes and reattach the retina (see Treatment, above). This usually brings back some but not all of your sight and prevents you from going blind.
Vision is affected because the retina is unable to function properly (see Symptoms, above). This means it has implications for driving.
There are several common causes of retinal detachment.
Many retinal detachments happen as a result of a tear or hole developing in the retina. This often occurs when the retina becomes thin, particularly among those who are short-sighted.
When the retina has holes in it, fluid in the eye can creep underneath the retina and separate it from the lining of the eye.
Retinal detachment can also be brought on by:
Retinal detachment cannot be caused by heavy lifting or by straining your eyes.
If your GP thinks that retinal detachment has occurred, they often perform a basic eye examination.
However, GPs are usually not able to look for and diagnose retinal detachment unless they are specially trained. They will need the help of an optometrist or eye specialist who will examine both of your eyes, even if only one of your eyes has been affected. If one retina is detached, you have a one in 10 risk of the other one detaching as well.
he most common symptom of retinal detachment is a shadow or 'black curtain' spreading across your vision.
Your vision may become cloudy as small blood vessels bleed into the vitreous (the 'jelly' inside your eye).
You may also experience:
There is no pain with retinal detachment.
It is normal to see the occasional floater, but floaters and flashes may be a sign of retinal detachment. If you experience these symptoms, consult your GP.
Having these symptoms does not always mean your retina has detached, but it is sensible to be cautious. Prompt treatment for retinal detachment minimises damage to your eye.
If retinal detachment has occurred, the only way of reattaching the retina is with surgery.
Without surgery, a complete loss of vision is almost certain. In 90% of cases, only one operation is needed to reattach the retina.
Surgery for retinal detachment may be done under a general anaesthetic (where you are put to sleep) or a local anaesthetic. You may need to stay in hospital for one or two days, but you may be able to leave on the same day, depending on the circumstances. You will be asked not to eat or drink anything for six hours before the operation.
Before you are given the anaesthetic, you will be given eye drops to widen your pupil.
The retina is usually reattached using either scleral buckling or vitrectomy.
Scleral buckling is the preferred way of reattaching the retina if it has a tear or hole in it.
Fine bands of silicone rubber or sponge are stitched onto the outside white of the eye (the sclera) in the area where the retina has detached. The bands act as a 'buckle' and press the sclera in towards the middle of the eye, so the torn retina can lie against the wall of the eye.
Laser or freezing treatment is used to scar the tissue around the retina (see the box, right), which creates a seal between the retina and the wall of the eye and closes up the tear or hole.
The bands can be left on the eye and should not be noticeable after the operation.
Vitrectomy works by removing the vitreous (jelly-like substance) from the inside of the eye and replacing it with either a gas or silicone bubble. This holds the retina in position from the inside.
Tiny dissolving stitches are used to close the wound. It is also possible to perform such surgery without the use of stitches, using smaller instruments. While this may lead to less discomfort, it is not known whether it is more effective.
After the procedure, you will be asked to keep your head in a certain position for a while, known as ‘posturing’, so the bubble lies against the retina.
If you have had a gas bubble in your eye, you will not be able to travel by air for a while. Your doctor will tell you when it is safe to fly again. If you need another operation requiring general anaesthetic, you must tell your doctors about the gas bubble in your eye.
There is a small chance of developing complications during or after surgery, including:
These complications are not common and can usually be treated. Sometimes, you may need more than one operation to fix the retina.