Retinal Detachment
What is Retinal Detachment?
Retinal detachment is a serious problem that usually affects middle-aged
or older people. If it isn't treated immediately, it will lead to vision
problems or even vision loss.
What Causes Retinal Detachment?
In most cases the retina detaches because of small tears or holes. These
may occur as the retina thins with age. More often, they happen because
the vitreous partially separates from the retina. The vitreous is firmly
attached to the retina in a few places, and as we get older it separates
and may tear the retina at those areas of attachment. In about half of
the population, the vitreous has separated from the retina by age 50.
Nearsightedness, infection or injury such as a hard solid blow to the
eye, can also make the vitreous separate. It is more common in people
with a family history of retinal detachment. When there is a hole in the
retina, fluid from the vitreous space may pass through the hole and flow
between the retina and the back wall of the eye. This can separate the
retina from the back of the eye and cause it to detach. The detached
part of the retina will not work properly, and you will see a blurry or
blind spot in your field of vision.
Less commonly, retinal detachment can also be caused by eye diseases,
complications of diabetes, or tumours. In these cases there may be no
tears or holes in the retina.
How is Retinal Detachment Diagnosed?
You may notice that spots or flashes of light have suddenly appeared in
your vision.
This can mean the vitreous is separating and possibly tearing the
retina. Your vision may seem wavy or watery, or you may have a shadow in
your side (peripheral) vision.
As the retina detaches further, central vision gets blurry. This can
lead to serious vision loss unless it is fixed. Sometimes retinal
detachment happens suddenly, leading to blindness in one eye. You may
also quickly lose sight if your retina is torn and bleeding into the
vitreous.
A detached retina is painless and cannot be seen from the outside of the
eye. If you notice symptoms, you should see an ophthalmologist right
away. If you are very nearsighted or have a family history of retinal
detachment, you should have regular eye exams by an ophthalmologist to
detect changes and prevent retinal detachment.
How is Retinal Detachment Treated?
If the retina is torn, you may be able to stop detachment by getting the
tear treated quickly. If there is little or no detachment, tears can
sometimes be sealed with a laser (called 'laser photo-coagulation'). The
laser makes small burns to seal the edges of the tear. This can be done
without a hospital stay.
The edges of the tear can also be sealed by freezing the wall of the eye
behind the tear (called 'cryopexy'). Cryopexy is also done without a
hospital stay, but you will need a local anesthetic to numb the eye.
If the retina is detached, you will need surgery to fix it. In over 90%
of cases, retinal detachment can be fixed successfully. Occasionally,
more than one operation is needed. Sometimes the ophthalmologist has to
drain fluid so the retina can settle onto the back wall of the eye. A
silicone band or pressure pad (called a 'scleral buckle') may be put on
the outside of the eye to push the back wall of the eye against the
retina. Then cryopexy, a laser, or an electric current applied through a
needle (called 'diathermy') will be used to seal the tear.
In more complicated cases, a procedure called a 'vitrectomy' is done.
This involves cutting the vitreous away from the retina and taking it
out of the eye. If the retina is shrunken and puckered from scar tissue,
it may be necessary to temporarily fill the space with air, gas or
silicone oil to push the retina against the back wall of the eye. If gas
is used, clear fluid eventually seeps into the vitreous cavity to fill
it again. Silicone oil is usually removed from the eye if the retina
remains attached.
About 40% of people who have their detachment successfully repaired have
excellent vision within 6 months of surgery. The results are not usually
as good when the retina has been detached for a long time or when there
is a fibrous growth on the surface of the retina. The other 60% of
people have various levels of reading and distance vision. If scar
tissue develops, the retina cannot always be reattached. In this case,
the eye will continue to lose sight and will eventually become blind.
© Copyright by the Canadian Ophthalmological Society