Paediatrics: Vision assessment

Vision assessment

Early visual development

At birth most babies can fix and follow horizontally. Initially, the eyes move independently and infant may appear to ‘squint’. Visual acuity is about 6/200. Retina is well developed, but the fovea is immature. Development of visual acuity is dependent on the production of well-formed images on the retina. A cataract will affect normal development of the optic pathway and visual cortex. Lack of normal development leads to amblyopia.

•   6wks: both eyes move together and will follow a light source.

•   3mths: visual acuity is 6/60. A baby should watch their hands and notice toys.

•   6mths: a baby reaches for toys and passes them from one hand to the other.

Vision screening

Assessment for visual problems should be performed on all children at the newborn examination, the 6–8wks review, and the pre-school (or school-entry) vision check.

Vision assessment

Birth

•   General observation: eye movements

·  Ophthalmoscopy:

•   Red reflex—dark spots in the red reflex can be due to cataracts, corneal abnormalities, or opacities in the vitreous. The red reflex may be absent with a dense cataract

•   White reflex—present with cataracts, retinoblastoma, or retinopathy of prematurity 6–8wks Optokinetics (e.g. nystagmus demonstrated by looking at a mov-ing, striped target)

2yrs Identification of pictures

3yrs Letter matching on the single letter chart, e.g. Sheridan Gardiner chart

5yrs Identification of letters on the Snellen chart

If the following are evident at the age of 6mths, it should arouse sus-picions:

•   Lack of eye contact/visual inattention

•   Random eye movements

Persistent nystagmus or squint