Changes
in vision can range from mild to severe, and may
be lasting or only temporary. For example, a person
may become completely blind or may have poor vision
only under certain conditions.
What is going on in the
body?
Common vision changes
can include - but are not limited to: ·
blurry vision · double vision ·
cloudy vision
Vision changes can be
caused by anything from normal aging to life-threatening
conditions. The exact changes in the body will
depend on the specific cause and type of vision
change.
What are the signs and
symptoms of the condition?
Kinds of vision changes
include: · decreased sharpness of vision,
which means either being unable to focus on
objects up close or far away, or both ·
double vision, which means seeing two of everything
· loss of peripheral, or side, vision
· total loss of vision, or blindness
· cloudy vision, which feels as though
the person is looking through a dirty windshield
· "blind spots," which means
the person has areas of vision where he or she
can only see blackness
What are the causes and
risks of the condition?
The possible causes of
vision changes include: · refractive
errors, such as being nearsighted, farsighted
or having presbyopia. Presbyopia is when a person
has a hard time seeing things up close, due
to age-related changes in the eye. This condition
affects most people over age 50. It's the reason
older people often need bifocals or reading
glasses. · infections of the eye, such
as conjunctivitis or keratitis · cataracts,
a common condition in older adults caused by
changes in the lens of the eye · glaucoma,
a condition caused by increased pressure within
the eye · damage or inflammation of the
nerves of the eye · damage to the vision
areas of the brain, due to a stroke or brain
tumor · damage to the retina, the part
of the eye that is similar to the film inside
a camera. The retina can be damaged in diabetes,
macular degeneration, or retinal detachment.
· trauma, or injury, to the eye ·
strabismus, sometimes known as lazy eye, in
which the eyes don't line up properly ·
temporal arteritis, an inflammation of the arteries
that supply blood to the eye · vitamin
A deficiency · medicines, such as the
heart medicine digitalis, or the antibiotic
ethambutol
Other causes of vision
changes are possible. Sometimes, no cause can
be found.
What can be done to prevent
the condition?
Prevention depends on
the cause. Early detection and treatment of
glaucoma can often prevent vision loss. Control
of diabetes can help prevent vision changes
caused by diabetic retinopathy. Frequent hand
washing and not touching the eyes with the hands
helps prevent conjunctivitis. Many cases of
vision changes cannot be prevented.
How is the condition
diagnosed?
A history and physical
exam, including an examination of the eye, are
done first. In an eye exam, the person may be
asked to read an eye chart. Special instruments
may be used, and the pressure inside the eye
may be measured. Eye drops can be put into the
eye to make the pupils get bigger. This helps
the doctor see the inside of the eye better.
The doctor will also
need to know the kind of vision changes the
person has noticed as well as: · when
the vision change started · whether it
came on quickly or slowly · whether one
or both eyes are affected · whether near
vision, far vision, or both, is affected ·
whether there is any pain associated with the
vision change · what medicines the person
takes · what other medical conditions
the person has · whether there is any
family history of vision changes
In addition, the doctor
may ask about other symptoms, such as: ·
headache · nausea · vomiting ·
weakness · muscle pains
These steps may be all
that's needed to make the diagnosis. In other
cases, further testing is needed.
The tests that are ordered
vary, depending on the suspected cause. A cranial
CT scan may be done if a brain tumor or stroke
is suspected. A blood test can help diagnose
temporal arteritis or diabetes.
What are the long-term
effects of the condition?
Long-term effects depend
on the cause. Presbyopia causes a permanent
loss of vision in near objects. But reading
glasses or bifocals are the only treatment needed
and there are no other long- term effects. A
brain tumor can cause death. Glaucoma, macular
degeneration, and diabetes can all result in
permanent blindness or vision changes.
What are the risks to
others?
Vision changes themselves
pose no risks to others unless the person engages
in dangerous activities such as driving. If
the cause of the vision change is an eye infection,
such as conjunctivitis or keratitis, the infection
may be catching in some cases.
What are the treatments
for the condition?
Treatment is directed
at the cause. Medicines are often used to control
diabetes or glaucoma. Retinal detachment, cataracts,
some types of glaucoma, and brain tumors can
be treated with surgery. Eye infections may
need to be treated with antibiotics. Nearsightedness
is usually treated with glasses or contact lenses.
What are the side effects
of the treatments?
Side effects depend on
the treatments used. All medicines may have
side effects. For example, those used to control
diabetes may cause liver damage or allergic
reactions. Surgery carries a risk of bleeding,
infection, or loss of vision. Contact lenses
may irritate the eyes or result in eye infections.
What happens after treatment
for the condition?
Treatment varies according
to the cause of the vision change. After a person
gets glasses, no further treatment may be needed
aside from periodic checkups. People who have
diabetes or glaucoma usually need close monitoring
and treatment for life. Macular degeneration
often causes vision to get worse over time,
so treatment may change.
How is the condition
monitored?
The doctor should be
told about any changes in vision or the responses
to treatments. Repeat eye exams are advised
for many causes of vision changes. Children
with a lazy eye may need close monitoring along
with surgery, special glasses, or a patch over
one eye.
