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
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
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
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.