Table 2 Visual function and tests to be performed
Visual function | Test | Performed by |
|---|---|---|
Presenting distance visual acuity | Lea symbols | Optometrist |
Presenting distance visual acuity | Peek visual acuity test; Peekaboo visual acuity test | Optometrist |
Presenting near visual acuity Reading | Lea symbols Goodlite children’s reading chart | Optometrist Optometrist |
Grating acuity | Lea paddles | Optometrist |
Contrast sensitivity | Hiding Heidi | Optometrist |
Colour vision | Acquired and congenital colour chart | Optometrist |
Visual fields | Lea Flicker Wand 280,000 | PI |
Stereopsis | Butterfly stereo acuity test with Lea symbols | Optometrist |
Eye movements | Â | PI |
Vergence | Observation of binocular movements of the eye, i.e. convergence and divergence, using a fixation target | PI |
Motion processing: smooth pursuit (horizontal and vertical) | Uncooperative or inattentive children are tested by slowly rotating a mirror that measures 10 cm by 15 cm held before their eyes Verbal children: the patient is asked to track the tip of a blue ball point pen held 1 m before the eyes with the head still; the target is moved at a low, uniform speed | PI |
Motion processing: saccades | Non-verbal: the infant or child is enticed to look at the tester’s face; when the fixation is in the midline, one of the objects is presented at about 20–30 cm from the midline and the infant or child is again enticed to look at the tester’s face after which the other object is presented on the other side. Verbal: the patient is asked to look at the examiner’s nose and then at the examiner’s finger to the left or right of central fixation only upon verbal command. | PI |
Strabismus | Corneal reflex test and modified Krimsky test | PI |
Accommodation | Near pupillary reaction method | PI |
Cycloplegic refraction | Cyclopentolate 2% + phenylephrine 2.5% Zeiss autorefractor/keratometer Manual objective retinoscopy | Optometrist PI |