The Development of Visual Function in Normal and Neurologically Abnormal Preterm and Fullterm Infants

Abstract

Pattern preference for 4 different pairs of patterns and visual acuity based on the ability to distinguish black and white stripes of different widths were compared in neurologically normal and abnormal preterm infants at 36 and 40 wk postmenstrual age and in normal and abnormal full-term infants in the newborn period and again at 4 and 6 wk of age. The study aimed to chart the maturation process of these visual functions in the neonatal period and to assess their predictive value in the neurologically abnormal infant. Part I of the study deals with the normal infant and part II with the abnormal infant. In part I, the maturation process for both visual functions in newborn preterm infants of increasing gestational age is compared with longitudinal assessment of postnatal maturation of these functions in preterm infants up to 40 wk postmenstrual age. Up to 36 wk postmenstrual age the functions were comparable in the maturing preterm infants and the newborn infants of comparable postmenstrual age, but at 40 wk the preterm infants did less well than the full-term newborn infants. In part II, the abnormal full-term infants demonstrated a significantly poorer pattern preference at the initial and subsequent examination. Visual acuity was significantly poorer at the initial examination but less marked at follow-up. The abnormal preterm infants showed poorer pattern preference and visual acuity at both 36 and 40 wk postmenstrual age. Compared with neurologically abnormal infants without intraventricular hemorrhage (IVH), preterm infants with IVH showed no significant difference in pattern preference at 36 and 40 wk, but a significant deficit in visual acuity.