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 Babies
have poor vision at birth but can see faces at close range, even
in the newborn nursery. At about six weeks a baby's eyes should
follow objects and by four months should work together. Over the
first year or two, vision develops rapidly. A two-year-old usually
sees around 20/30, nearly the same as an adult.
Parents should be aware of signals of poor vision. If one eye turns
or crosses, that eye may not see as well as the other eye. If the
child is uninterested in faces or age-appropriate toys, or if the
eyes rove around or jiggle (nystagmus), poor vision should be suspected.
Other signs to watch for are tilting the head and squinting. Babies and toddlers compensate for poor vision rather than complain
about it.
Should a baby need glasses, the prescription can be determined
fairly accurately by dilating the pupil and analyzing the light
reflected through the pupil from the back of the eye.
A baby's vision can also be tested in a research laboratory where
brain waves are recorded as the child looks at stripes or checks
on a TV screen. The test is called Visual Evoked Potential (VEP).
Another test called preferential looking or Teller Acuity Cards
uses simple striped cards to attract the child's attention. In both
tests, as the stripes grow smaller, the child eventually does not
respond (with brain waves or by looking at the stripes).
People are often confused about the importance of glasses for children.
Some believe that if children wear glasses when they are young,
they won't need them later. Others think wearing glasses as a child
makes one dependent on them later. Neither is true. Children need
glasses because they are genetically nearsighted, farsighted, or
astigmatic. These conditions do not go away nor do they get worse
because they are not corrected. Glasses or contacts are necessary
throughout life for good vision.
Nearsightedness (distant objects appear blurry) typically begins
between the ages of eight and fifteen but can start earlier. Farsightedness
is actually normal in young children and not a problem as long as
it is mild. If a child is too farsighted, vision is blurry or the
eyes cross when looking closely at things. This is usually apparent
around the age of two. Almost everyone has some amount of astigmatism
(oval instead of round cornea). Glasses are required only if the
astigmatism is strong.
Unlike adults, children who need glasses may develop a second problem,
called amblyopia or lazy eye. Amblyopia means even with the right
prescription, one eye (or sometimes both eyes) does not see normally.
Amblyopia is more likely to occur if the prescription needed to
correct one eye is stronger than the other. Wearing glasses can
prevent amblyopia from developing in the more out-of-focus eye.
Children (and adults) who do not see well with one eye because
of amblyopia, or because of any other medical problem that cannot
be corrected, should wear safety glasses to protect the normal eye.
 Prescriptions
for glasses can be measured in even the youngest and most uncooperative
children by using a special instrument called a retinoscope to analyze
light reflected through the pupil from the back of the eye.
Most lenses today, especially for children, are made of plastic,
which is stronger and lighter than glass. It is a good idea to get
a scratch-resistant coating on plastic lenses. Children can be rough
with glasses and plastic lenses scratch easily.
Color tints or tints that respond to changes in light can be incorporated
into lenses. For children, the tint should not be so dark that the
child has trouble seeing indoors.
Frames come in all shapes and sizes. Choose one that fits comfortably
but securely. There are devices available to keep glasses in place,
a good idea for active children and young children with flat nasal
bridges. Cable temples, which wrap around the back of the ears,
are good for toddlers. Infants may require a strap across the top
and back of the head instead of earpieces. Flexible hinges hold
glasses in position, allow the glasses to "grow" with
the child, and prevent the side arms from being broken.
Children often do not like their glasses although the prescription
is correct. Distraction, positive reinforcement, and bribery help
children get in the habit of wearing glasses. If all else fails,
your ophthalmologist can prescribe an eye drop that blurs vision
when the glasses are not in place. This often overcomes the child's
initial resistance to wearing glasses.
When children have difficulty reading, parents often think poor
vision is the problem. If a visit to an ophthalmologist rules out
any medical or vision problems, it may be a learning disability.
A learning disability is a disparity between a person's ability
and performance in a certain area. It has nothing to do with intelligence
or IQ. A learning disability can make it difficult to succeed in
school and, if untreated, gets worse, causing a child to lose self-confidence
and interest in school.
Identifying the learning disability is the first step in treating
it. Dyslexia, a reading disability that may involve reversing letters
and words, is one of the many learning disorders that can affect
reading.
Exercises have been used to improve the coordination or focusing
of the eyes. Since poor reading is not usually an eye problem, these
exercises rarely prove helpful. Colored lenses, special diets or
vitamins, jumping on trampolines, or walking on balance beams have
also been prescribed without much success. Over time, these methods
have tended to fall out of favor. Children with learning disabilities
benefit from various educational programs, in or out of school.
Parents also play a vital role. They can support their children
by reading with them at home.
Children with learning disabilities need to be encouraged to develop
strengths and interests so they can fully develop their unique talents
and abilities.
 Accidents
resulting in serious eye injuries can happen to anyone, but are
particularly common in children and young adults. More than 90%
of all eye injuries can be prevented with appropriate supervision
and protective eyewear.
Goggles and face protection can prevent injuries in sports like
baseball, basketball, racket sports, and hockey. It is more difficult
to protect against injuries in boxing, though thumbless gloves help.
People who must rely on only one good eye should wear polycarbonate
safety glasses all the time and should wear safety goggles for sports
and other dangerous activities. Choose frames and lenses that meet
the American National Standards Institute standard for safety (Z87.1).
Appropriate adult supervision is key in preventing all eye injuries.
Children should never be allowed to play with fireworks or BB guns.
Sharp and fast-moving objects, such as darts, arrows, scissors,
knives, and even pencils or pens can be dangerous. Special care
should be taken when working around lawn mowers, which can throw
rocks and debris, and when banging two pieces of metal together,
which can dislodge small shards of metal. Chemicals such as toilet
cleaners and drain openers are especially hazardous.
A primary care physician or an emergency room can treat minor injuries,
such as a foreign body or an abrasion (scratch) on the cornea. Any
foreign material must be removed from the eye. An antibiotic drop
or ointment may be applied, perhaps with an eye patch for comfort.
More serious injuries, like blood inside the eye (hyphema), a laceration
(cut), or rupture of the eye, require examination by an ophthalmologist.
Both surgery and hospitalization may be necessary.
Chemicals that burn should be rinsed from the eye immediately.
The ultimate outcome depends on the severity of the injury, which
cannot always be identified in the initial examination.
Strabismus refers to misaligned eyes. If the eyes turn inward (crossed),
it is called esotropia. If the eyes turn outward (wall-eyed), it
is called exotropia. Or, one eye can be higher than the other which
is called hypertropia (for the higher eye) or hypotropia (for the
lower eye). Strabismus can be subtle or obvious, intermittent (occurring
occasionally), or constant. It can affect one eye only or shift
between the eyes.
Strabismus usually begins in infancy or childhood. Some toddlers
have accommodative esotropia. Their eyes cross because they need
glasses for farsightedness. But most cases of strabismus do not
have a well-understood cause. Acquired strabismus can occasionally
occur because of a problem in the brain, an injury to the eye socket,
or thyroid eye disease.
When young children develop strabismus, they typically have mild
symptoms. They may hold their heads to one side if they can use
their eyes together in that position. Or, they may close or cover
one eye when it deviates, especially at first. Adults, on the other
hand, have more symptoms when they develop strabismus. They have
double vision (see a second image) and may lose depth perception.
At all ages, strabismus is disturbing. Studies show school children
with significant strabismus have self-image problems.
Amblyopia, or lazy eye, is closely related to strabismus. Children
learn to suppress double vision so effectively that the deviating
eye gradually loses vision. It may be necessary to patch the good
eye and wear glasses before treating the strabismus. Amblyopia does
not occur when alternate eyes deviate, and adults do not develop
amblyopia.
Strabismus is often treated by surgically adjusting the tension
on the eye muscles. The goal of surgery is to get the eyes close
enough to perfectly straight that it is hard to see any residual
deviation. Surgery usually improves the conditions though the results
are rarely perfect. Results are usually better in young children.
Surgery can be done with local anesthesia in some adults, but requires
general anesthesia in children, usually as an outpatient. Prisms
and Botox injections of the eye muscles are alternatives to surgery
in some cases. Eye exercises are rarely effective.
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