Patient Education: Retinal Tear and Detachment
What is the retina?
The retina is the light-sensitive layer of tissue covering the inside of the back of the eye. It is similar to film in a camera and "sees" the image formed by the front of the eye. The centre of the retina is called the macula. The vitreous is a clear, jelly-like fluid that fills the inside of the eye and is attached to the retina at certain points.
What is a retinal detachment?
A retinal detachment occurs when the retina is pulled away from its normal position. The retina loses function when it is detached because the nutrition does not reach the retina. Therefore, the vision is blurred in the area of the retinal detachment. A retinal detachment is a serious condition and may result in blindness unless it is treated.
What causes retinal detachment?
The vitreous is a clear gel that fills the middle of the eye. As we get older, the vitreous may pull away from its attachment at the back of the eye. This is termed a vitreous detachment. Usually a vitreous detachment does not cause significant problems.
Sometimes the vitreous may have a strong attachment to the retina. The vitreous pulls hard enough to tear the retina in one or more places. The fluid inside the eye then passes through the retinal tear and lifts the retina off the back of the eye. This is like wall paper peeling off a wall.
A retinal tear and detachment may also result in bleeding into the interior of the eye. This is termed a vitreous haemorrhage.
The following conditions may increase the chance that you might get a retinal detachment:
Near sightedness (Myopia)
Previous retinal detachment in your other eye
Family history of retinal detachment
Previous injury to the eye
Weak areas that have been identified by your ophthalmologist (lattice degeneration).
What are the warning symptoms of retinal detachment?
Some of the early symptoms that may indicate the presence of a retinal detachment include:
Flashing lights. These are bright and very rapid flashes lasting seconds.
Changes to existing floaters or new floaters, or a sudden onset of floaters.
A black curtain/cobweb/shadow/cloud moving across your field of vision.
These symptoms do not always mean a retinal detachment is present. However, you should see your ophthalmologist as soon as possible.
How is a retinal detachment diagnosed?
An ophthalmologist can diagnose a retinal detachment during an eye examination after dilating your pupils. Only after careful examination can your ophthalmologist tell whether a retinal tear or retinal detachment is present.
What treatment is needed for a vitreous detachment?
In an uncomplicated vitreous detachment no treatment is required. However, your ophthalmologist will arrange follow-up to ensure that no further problems occur.
What treatment is needed for retinal tears?
Retinal tears require treatment using laser surgery or retinal cryotherapy (freezing), which seals the retina to the back wall of the eye.
Laser is often performed using a lens placed on the eye as an outpatient procedure in the Clinic. Retinal cryotherapy is performed in the Day Surgery using local anaesthesia. These procedures do not involve open surgery.
What treatment is needed for a retinal detachment?
Patients with retinal detachment require surgery to put the retina back into its proper position.
There are several ways to fix a retinal detachment. The decision on which type of surgery depends on the characteristics of your detachment. In each of the following methods, the ophthalmologist will locate the retinal tears and use laser surgery or cryotherapy to seal the tear.
The vitreous gel, which is pulling on the retina, is removed from the eye and usually replaced with a gas bubble. In cases of advanced retinal detachment, where long term pressure on the retina is required, silicone oil or heavy liquid may be used. Your body’s own fluids will gradually replace the gas bubble. Sometimes vitrectomy is combined with a scleral buckle.
A silicone band (scleral buckle) is placed around the outside of the eye to counteract the force pulling the retina out of place. The ophthalmologist drains the fluid under the detached retina from the eye, pulling the retina to its normal position against the back wall of the eye. A gas bubble is injected into the vitreous space inside the eye. The gas pushes the retinal tear closed against the back wall of the eye.
What should I expect after surgery?
You can expect some discomfort after surgery. Your ophthalmologist will prescribe eye drops for you and advise you when to resume normal activity.
If a gas bubble was placed in your eye, you may be required to maintain a certain head position for several days in order for the gas to place pressure on the area of retinal detachment. This may continue for several days. The gas bubble will gradually disappear over days to weeks depending on the type of gas used. There is equipment available to hire to make this position more comfortable.
Do not fly in an airplane or travel to high altitudes until you are told the gas bubble is gone. A rapid increase in altitude may cause a dangerous rise in eye pressure.
You will be given a wrist bracelet to warn Medical Staff against giving nitrous oxide whilst gas remains in the eye.
If gas is used during surgery, vision will be poor until the gas bubble is absorbed by your body.
What are the risks of surgery?
Any surgery has risks. However, an untreated retinal detachment usually results in permanent, severe vision loss or blindness.
Some of the risks of surgery include:
- High pressure in the eye
Most retinal detachment surgery is successful, however a second operation is sometimes required. This may be due to scarring of the retina called proliferative vitreoretinopathy (PVR). This scar may pull on the retina causing it to tear and re-detach. If the retina cannot be reattached, the eye will continue to lose sight and ultimately becomes blind.
Will your vision improve?
Vision may take many months to improve and in some cases may never return fully. The more severe the detachment, the less vision that returns. Therefore, it is very important to see your ophthalmologist at the first sign of any trouble.