Retrolental Fibroplasia and Light

The intensity of light in the hospital neonatal intensive care unit has increased five-to tenfold during the past two decades. In the 1960s the ambient level of light was approximately 10 foot-candles (ft-c), whereas in 1982 it was 90 (range, 30 to 190 ft-c). In addition, most preterm infants are now exposed to supplemental sources of light, such as heat lamps, high-intensity lights for performing minor surgical procedures, and the phototherapy lamp (300 to 400 ft-c). There is growing concern about the possible consequences of this exposure to light for the weeks and months of stay in the hospital nursery. Glass et al prospectively investigated the effect of exposure to light in two intensive care nurseries by comparing the incidence of retinopathy of prematurity among 74 infants from the standard light nursery environment (median light level 60 ft-c) with the incidence among 154 infants of similar birth weight for whom the light levels were reduced (median 25 ft-c).