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
eyedrops, oral medications, laser treatment or even
surgery may be involved. If untreated, glaucoma can
cause blindness, and there are 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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