| Dry Eye |
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| What
is Dry Eye? |
Tears serve to
lubricate the eye and they are produced around
the clock, but when insufficient moisture
is produced stinging, burning, scratchiness
and other symptoms are experienced and may
be referred to as Dry Eye, Keratitis Sicca,
Keratoconjunctivitus Sicca (KCS) or Xerophthalmia.
When we blink, tears form a film, which spreads
over the eye, making the surface smooth and
optically clear and enabling good vision.
There are three layers in the thin film of
tears: an oily layer, a watery layer and a
layer of mucus, each with specific function.
The outermost, oily layer is produced by small
glands at the edge of the eyelid (meibomian
glands) and the main purpose of this layer
is to smooth the tear surface and reduce evaporation.
The middle, watery layer, is produced by small
glands through the conjunctiva, (the delicate
membrane lining the inside of the eyelid)
and by the large lacrimal (tear) gland. This
layer cleanses the eye and washes away foreign
particles of irritants. The innermost layer
consists of mucus which allows the water layer
to spread evenly over the surface of the eye.
Without mucus, tears would not adhere to the
eyelid |
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| What
causes Dry Eye? |
Dry
eye is caused when the tear gland produces
insufficient tears. This can happen as part
of the normal ageing process. It is more common
among women, so although the condition is
not common it tends to occur with increasing
age when it is not always noticed because
the effect of dry eye tends to balance another
age-related change: poor tear drainage. The
result of this is an imbalance caused by a
reduction in lacrimal fluid.
People with Sjogren’s syndrome are at
risk of dry eye as part of a more systemic
problem involving salivary glands and other
sites of mucus membrane. Salivary gland involvement
produces a dry mouth as well. This syndrome,
and dry eyes generally, may be found in people
with rheumatoid arthritis. |
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What are the effects of the condition? |
| People with dry
eye rarely have a sensation that the eye is
dry but instead experience irritation, burning,
a sensation of having a foreign body in the
eye, mucus discharge and possible temporary
blurring of vision. Blinking may cause pain
to people with severe forms of keratitis |
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Is there any treatment for Dry Eye? |
The
aim of treatment will be to relieve discomfort
and prevent corneal damage. In some situations
relief may be found by blinking consciously
when doing close or continuous work. It is
also helpful to close the eyes for a spell
from time to time.
Eye drops may be prescribed or purchased over
the counter and since there is a variety,
it may be helpful to try others if your present
product does not suit you. Some drops contain
preservative, which means they are safe to
use for a month after opening, but although
these drops are cheap are cheap and suitable
for most sufferers, some people do not tolerate
the preservative and may need to get prescription
from the hospital pharmacy for a preservative
free medication.
Lubricant ointments are also helpful, particularly
at night. These are also available without
preservative. Some women benefit from hormone
replacement therapy (HRT), especially those
whose dry eye problems began around or after
the menopause.
Antihistamines or certain types of travel
sickness pills inhibit tear secretion and
symptoms can vary from day to day and be affected
by general health. Surgical procedures may
be indicated if symptoms are severe despite
drops.
It involves closing the tear drainage holes
in the eyelids permanently. It is a minor
operation, which is suitable for some patients.
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| Is
there anything that can help? |
Avoiding
the following situations will minimise your
risk of Dry Eye:
- Reduce the dry eye atmosphere caused
by central heating by using a humidifier.
- Avoid car heaters, particularly at
face level.
- Sit away from direct heat such as gas
or electric fires.
- Use eye drops just before activities,
which cause additional pain or discomfort
such as television, reading, sewing and
writing.
- Remember to blink regularly, particularly
when doing close or concentrated work.
- Blink properly with full lid closure,
not ‘half’ blinking.
- Avoid smoky atmospheres.
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Will the condition
improve? |
| Prognosis varies
considerably and may depend in art upon individual
lifestyle choices and overall health as well
as the severity and cause of the condition.
There is no definite cure, but people can
usually be made more comfortable. |
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