Visual field extent in infants and toddlers: Effect of stimulus and procedural variations

Purpose. To study the effect of stimulus parameters and procedural variations on measured visual field size in children 7 months to 2 1/2 years of age. Methods. Visual field extent along 4 diagonal meridia was measured monocularly in 30 seven-month-olds, 28 nine-month-olds, and 22 adults, and binocularly in 30 eleven-month-olds, 21 seventeen-month-olds, and 29 thirty-month-olds. All subjects were tested with static perimetry (SP), in which a 3-deg, 10 Hz, 1.5 log cd/m² maximum luminance LED stimulus was presented for 5-sec at each of 3 positions along each meridian and hybrid perimetry (HP), in which 3-deg, 10 Hz, 1.5 log cd/m² LED stimuli, separated by 10 deg, were illuminated sequentially at 2-sec intervals, in a peripheral to central direction. Adults and 7-, 17-, and 30-month-olds were tested with white sphere kinetic perimetry (WSKP), in which a 3-deg, 2.0 log cd/m² white sphere moved centrally at 2-3 deg/sec. Results. SP visual field size averaged 58%, 66%, 78%, 72%, and 89% of adult values, respectively, at the 5 test ages. At the same ages, HP visual field size averaged 52%, 65%, 74%, 73%, and 82% of adult values. WSKP field size averaged 81%, 86%, and 96% of adult values at 7, 17, and 30 months, respectively. Conclusions. SP, HP, and WSKP all showed expansion of temporal field size between ages 7 and 30 months. However, measured visual field extent appears more adult-like when tested with the brighter, 3-dimensional, moving stimuli used in WSKP than with the stationary flickering lights used in SP and HP.