Katrina M. Bourne, DipAppSc(Cumb), DOBA
Ann M. Crampton, DipAppSci(Cumb), DOBA
Cathie M. Searle, DipAppSci(Cumb), DOBA
A screen, called the “Baby Visual Field Screen” has been developed to assist with plotting and describing the visual fields of infants, toddlers and physically or mentally handicapped patients.
The screen is made of transparent Perspex, is free standing, and is of similar dimensions to a one metre Bjerrum’s screen.
During the examination the infant is seated on the parent’s lap, one metre from the screen. Central fixation is elicited by one examiner behind the screen showing the subject a succession of toys, faces and/or talking to the infant as required. A second examiner introduces targets into the infant’s peripheral visual field and moves them toward the centre, until the infant fixates the target or makes some sign of recognition. The targets were finger puppets of equal size and luminosity. The two examiners agreed on the point where the infant fixated the peripheral target and plotted this point on the screen. Horizontal, vertical and diagonal meridian were tested.
Monocular fields were plotted for twelve adults and twelve normal infants ranging in age from five to ten months and binocular fields for six infants of two and three months of age. Results indicate that the screen provides an accurate indication of a normal visual field. In a group of 13 infants and children at risk for visual field defects, the method was able to detect and recorded defects in live cases.