Strabismus - Fundamentals of Clinical Ophthalmology.pdf

6 Assessment of strabismus
This chapter includes key points to consider in
history taking and outlines a basic approach to
assessing visual acuity and eye movements in
preverbal children and adults. In preverbal
children most reliance is placed on motor tests
and observation. In the older child and adult
sensory tests are complementary to motor tests.
The infant and preverbal child
Whilst a history is being taken, the child should
be left undisturbed in a stroller, or the older child
be allowed to play with toys. It is better if the
doctor is not wearing a white coat or other
trappings of the profession. An atmosphere of
friendliness should be nurtured and the examination
should be fun and, as far as possible, be an
extension of a game. More can be gained from
informality than from formality with children.
Vision in the newborn and developing infant
excites the curiosity of a child to explore their
environment, integrated with neck and general
body movement. The visual interest that a child
has in its environment will be strongly influenced
by the child’s intelligence and attentiveness.
The assessment and examination of the
oculomotor system must be a reflection of both
eye movements and visual function, both
monocular and binocular. Strabismus that has
its onset in childhood is particularly important
because of the association between strabismus
and amblyopia. Assessment and management of
amblyopia is discussed in Chapter 7.
History
In addition to an account of the parent’s
perception of their child’s strabismus, it is
important to ask who first observed the
strabismus and the observations they made. It is
also important to take great care in determining
the child’s general health and development.
Open-ended questions are important in focusing
upon the problems of most concern to the
parents. Where vision is at risk, careful questions
about hearing should also be made. For
example, what is the child’s response to the
sound of the telephone or a knock at the door?
As vision strongly excites a child’s interest,
apparent delay in motor development may be a
clue for visual impairment.
Other questions should include enquiry about
the pregnancy, occurrence of rash, fevers,
medications and drug abuse including alcohol,
particularly in the early months of pregnancy.
Family history should also be taken regarding
eye movement disorders, but also hereditary
visual defects, such as retinitis pigmentosa.
Questions about the child’s vision and how this
compares to other children of similar age or
siblings at the same age may also be helpful.
History and examination of a child with a
squint should seek to establish that:
●
●
the underlying cause of the strabismus is
static; either monocular or binocular
the vision in each eye is normal and equal
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