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Assessment of visual acuity and fixation pattern
Ocular alignment and motility for near and distance
Extraocular muscle function (ductions and versions including incomitance, such as A
and V patterns)
Detection of nystagmus
Sensory testing
Red reflex or binocular red reflex (Brückner) test
Pupil examination
External examination
Anterior segment examination
Cycloplegic retinoscopy/refraction
Funduscopic examination
Binocularity/stereoacuity testing
Assessment of Visual Acuity and Fixation Pattern
The method of evaluating visual acuity varies according to the child’s age and level of
cooperation. Preverbal children should be checked for objection to cover and the presence
of a fixation preference. When possible, monocular distance visual acuity should be
determined utilizing a recognized optotype, such as the tumbling-E, Lea figures, or Snellen
letters.
Anomalous head posture is suggestive of peeking around the occluder. An occlusive patch
over the non-tested eye can distinguish between peeking and possible eccentric fixation.
Monocular visual acuity testing for patients with nystagmus may require blurring of the
contralateral eye with a high plus lens (+4.00 D to +5.00 D). Binocular and monocular
testing also should be performed for patients with nystagmus.
Testing visual acuity with isolated targets (figures or letters) is the quickest way to assess
the vision in preverbal children, but it does lead to falsely elevated visual acuities. Isolated
acuities should be compared with visual acuities taken with linear targets or crowding bars.
The difference between linear and isolated acuities should be noted at each visit, if
possible. This difference is a way of quantifying the depth of amblyopia from visit to visit.
Under ideal circumstances, visual acuity testing conditions should be standardized in each
examination room and at each visit, so that the same viewing distance and lighting
conditions are used. Some children are more amenable to testing at shorter distances.
Young children sometimes benefit from shorter testing distances, especially when a visual
or attention deficit is suspected. The testing distance, type of optotype, and whether the
optotype is presented a line at a time or isolated, should be documented. Patients should
be encouraged to learn optotype-equivalent tests at the earliest possible age.
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