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Burian Lecture: Assessment of Visual Function in Children

I feel very honored to have been chosen to present the 2012 Burian Lecture. It is a great privilege but it is a difficult task to choose what to speak about. The work of the orthoptist has become immensely diverse over the last 4 decades during which I have practised orthoptics. It now includes many children with various neuropediatric disorders affecting the visual system. All visual functions (visual acuity, contrast sensitivity, visual fields, binocular vision, color vision, light and dark adaptation, perception, and cognition) are important to consider when assessing a child’s vision. I have chosen to mainly speak about visual acuity, contrast sensitivity, visual fields, and cognitive functions, and will present results from my clinical experience in combination with results from research. Normal visual development occurs from birth up to the age of 10–12 years and requires a normal visual system. What can a newborn child see and how does the vision develop? A newborn child can hear quite well, but the vision is subnormal and has not developed much. The visual acuity in a newborn child is approximately 0.01–0.05, at 6–12 months 0.1, at 2 years 0.25, at 3 years 0.5–0.65, at 4 years 0.8 and at 6 years 1.0. Not until the age of 10–12 years is the visual acuity fully developed, approximately 1.3–1.6. However, the acuity values depend to a great extent on the methods used in the examination. This will be discussed in more detail. Visual acuity is the most commonly measured visual function. There are a number of tests used for assessing visual acuity in children, but how reliable are the different tests and which tests can be recommended at different ages? METHODS TO ASSESS VISUAL ACUITY