Ocular & Visual Conditions
Amblyopia (lazy eye)
Amblyopia or lazy eye describes weak vision or vision loss in one
eye that cannot be fully corrected with lenses.
It usually develops in children before age
eight. This is also the key time to treat amblyopia, since
results are better the earlier they are implemented. It becomes
extremely difficult to treat amblyopia after age eight. Untreated,
amblyopia can lead to total blindness in the affected eye.
Amblyopia is more than simply an eye health
problem. It involves the wiring of the nerve
impulses from the eyes to the brain. Treatment typically
includes vision therapy, eyeglasses and contact lenses, or
a patch. Surgery alone cannot treat amblyopia.
Astigmatism
Astigmatism is an irregular curvature of the front surface of the eye that
results in blurred vision at all distances.
It is a common refractive error, just like
nearsightedness and farsightedness. It is usually a condition
from birth that progresses over time. Eyeglasses, contact
lenses and refractive surgery are all effective treatments
for astigmatism.
Cataracts
Cataracts are a clouding of the eyes crystalline lens that usually develops
slowly over time. (In the case of post-traumatic cataracts, however, they can
also occur very quickly.) It is the leading cause of poor vision in adults.
Symptoms: Dimmed
or blurred vision, double vision, halos or glare around
lights, colours appearing less brilliant, feeling of a
film over the eyes, frequently cleaning eyes, difficulty
driving or reading, and frequently changing or cleaning
glasses.
Treatment: If
a cataract grows larger or denser, it can be surgically
removed. Its a safe procedure with a near 100 per
cent success rate. Following surgery, its normal
to require a change in spectacle correction.
Prevention: Wearing
UV protection when outdoors is very helpful. There is also
some evidence to suggest that a diet high in beta carotene
(vitamin A), selenium and vitamins C and E have preventative
benefits. Avoiding cigarette smoke, air pollution and alcohol
consumption may also help.
Farsightedness (hyperopia)
Hyperopia, or farsightedness, is a common
refractive error. Approximately 25 per cent of
the general population may be affected. Farsighted
individuals see better in the distance than up
close because the eye does not effectively focus
light. Farsightedness is very common among elementary
school-age children and a frequent cause of reading
and learning difficulties.
Refractive errors such as hyperopia are
commonly corrected by eyeglasses or contact lenses. Refractive
surgery is another possibility.
Glaucoma
Glaucoma is a condition in which elevated pressure in the eye, damages the optic
nerve, causing peripheral and then total blindness. It is widely noted as
the second-leading cause of blindness in the U.S.
Symptoms:
There may be no early warning signs, so optometrical exams
are crucial. Otherwise, pain, blurred vision and the appearance
of coloured rings around lights are leading indicators.
Treatment: Once diagnosed, glaucoma treatments are highly effective. Prescription eye drops, oral medications, laser treatment or even surgery may be involved. If untreated, glaucoma can cause blindness, which has no cures.
Prevention: Because
there may be few symptoms, and vision lost to glaucoma
cannot be restored (the condition can only be halted),
frequent monitoring for glaucoma is essential. The risk
for glaucoma increases dramatically after age 35 and is
often hereditary.
Macular degeneration
Macular degeneration is a condition in which the macula (the part of the retina
responsible for sharp reading vision) fails to function efficiently. It is
a common cause of impaired reading or detailed visionthe leading cause
of blindness worldwide, in fact. Macular degeneration is generally age-related.
Symptoms: Initial
signs include blurred reading vision, a weakening of colour
vision, distortion or loss of central vision (e.g., a dark
spot in the middle of your field of vision), and distortion
in vertical lines.
Treatment: Although
there is no cure, laser treatment can be effective in slowing
the diseases progression. As usual, early detection
is key.
Prevention: Lifelong
UV protection is very important. General nutrition is also
believed to play a significant preventative role. Zinc
may be especially helpful in this regard, particularly
for zinc-deficient people like seniors. There is also some
evidence to suggest that a diet high in beta carotene (vitamin
A) and vitamins C and E can protect the macula. However,
an over-abundance of any vitamin may affect your bodys
ability to absorb important nutrients. This is a matter
of some debate among health care professionals.
Nearsightedness (myopia)
Myopia, more popularly known as nearsightedness, is a common refractive error.
Approximately a quarter of the general population may be affected. Myopic
individuals see better up close than in the distance. This is because the
eye improperly focuses too much light, causing blurred vision in the distance.
Refractive errors are commonly corrected by eyeglasses or contact lenses. Refractive
surgery and Ortho-Keratology are two other possibilities.
Presbyopia
Presbyopia is an inevitable condition in which the ability to focus on close
objects decreases over time. Since it is a natural effect of aging, it is extremely
commonplace.
In recent years, an estimated four million
new cases of presbyopia have been diagnosed. Todays baby
boomer generation is the most rapidly growing population
segment requiring vision correction.
Symptoms: Headaches,
blurred near-distance vision, tearing, stinging, or a need
for more light. People with presbyopia often hold reading
material at arms length.
Treatment: Reading
glasses (typically bifocals) or special contact lenses
are useful treatments, although the period of adjustment
can vary widely. All told, there is a wide range of corrective
options to review with your Optometrist.
Prevention: There
is no recognized prevention available, although focusing
difficulties can be relieved with corrective lenses.
Further questions: For
such a common condition, there are many misconceptions
about presbyopia. For example, it does not affect a persons
lifestyle, but presbyopia can require frequent prescription
changes after age 40.
Strabismus (crossed
eyes)
Strabismus or "crossed eyes" is a misalignment of the eyes. One or
both eyes may turn in (esotropia), out (exotropia), up (hypertropia) or down
(hypotropia). Treatment may include the use of eyeglasses, contact lenses,
prisms and/or vision therapy. In extreme cases, surgery may be needed.
All content is provided for education
and information, and is no substitute for the advice of
your optometrist. This information is provided courtesy
of the British Columbia Association of Optometrists (B.C.A.O.).
The B.C.A.O. assumes no responsibility or liability arising
from any errors or omissions or from the use of any information
contained herein.
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