RT Book, Section A1 Walton, David S. A2 Rudolph, Colin D. A2 Rudolph, Abraham M. A2 Lister, George E. A2 First, Lewis R. A2 Gershon, Anne A. SR Print(0) ID 7059848 T1 Chapter 584. Visual Impairment in Childhood T2 Rudolph's Pediatrics, 22e YR 2011 FD 2011 PB The McGraw-Hill Companies PP New York, NY SN 978-0-07-149723-7 LK accesspediatrics.mhmedical.com/content.aspx?aid=7059848 RD 2024/04/20 AB Vision is an essential sensory input from infancy and throughout childhood that allows for normal physical, cognitive, educational, and social development and for adult occupational training. Vision is present at birth at approximately a 20/200 level. Visual acuity develops rapidly during the first year, with normal acuity reached by 9 to 12 months of age. Blindness or visual impairment can be assessed in terms of the level of visual function and by scoring functional vision related to quality-of-life achievements. Assessment of visual acuity is the most often used parameter for estimating vision. The assessment of visual acuity in young children is imprecise. Therefore, it is necessary to define ranges of visual loss. Also test results may improve with advancing age and development. Levels of visual function, ranging from normal to visually impaired, have been categorized into five levels of performance (Table 584-1).