|
Home > Eye
conditions > Presbyopia
Presbyopia
What is Presbyopia?
During middle age people experience
blurred vision when reading or looking at objects close up.
Presbyopia is a natural part of the ageing process resulting
in a gradual decline in the ability to focus on close objects
or to see
small print. Presbyopia is due to the lens losing
its flexibility, making it more difficult to focus on
objects up close.
This condition becomes evident in almost all people over
the age of 45.
Causes of Presbyopia
In order for the eye to focus on an object, the lens changes
shape depending on the distance of
the object.
For the eye to focus on an object
up close, this will require the ciliary muscle (which controls
the shape of the lens) to contract inorder for the lens to
thicken
and
increase the focusing
power to the eye.
To focus on something
at a distance the ciliary muscle relaxes, which causes the
lens to flatten.
With the natural ageing process the eye's lens stiffens,
and it is less able to focus on objects up close. These changes
occur within the proteins in the lens, causing the lens to
become harder and less elastic. Age-related
changes also take
place in the ciliary muscle surrounding the lens.
Diagnosis of Presbyopia
As presbyopia comes on gradually with age (usually in the
40's onwards) most people don't notice small vision changes
and delay seeking professional
help until the
focusing problems interfere with daily life. Many optometrists
joke that patients seek help only when their arms become "too
short," as they are unable to hold printed pages far
enough away from them inorder to see clearly.
Presbyopia
will be diagnosed by an
optometrist,
ophthalmologist or eye care professional who will test your
vision
If the diagnosis is presbyopia, a test
will be undertaken to determine the extent of the focusing
problem and the appropriate lens prescription.
Treatments for Presbyopia
The most common form of treatment for presbyopia is with
prescription or reading glasses. Long sighted glasses
wearers with presbyopia will need to use bifocals. These are
lenses for both distance vision
and for observing objects close up.
Bifocal contact lenses are another option which provide
the convenience of contact lenses and the ability
to see close up as well as far away.
Another popular alernative is monovision where one eye
is used for viewing in the distance, and the other eye for
viewing things up close.
It is also possible to postpone or slow down the hardening
of the lens through good nutrition, aerobic exercise and a
healthy lifestyle.
Refractive surgery for presbyopia is an option that many
people enquire about, however many procedures are
in investigational stages. There is a lot of disagreement
about the causes of presbyopia, and so many of the new procedures
have little incommon with each other as they
treat different possible causes.
Procedures
such as monovision
LASIK eye surgery works well for many patients regardless
of the cause of presbyopia.
|