The Pupils of Korean Neonates

ABSTRACT

In an attempt to know the nature of the pupils in neonates, the authors studied the pupil diameter and net miosis to the light stimulation of 70 neonates ranging from 27.3 weeks to 42.0 weeks of gestational age. The mean corneal diameter was 9.3mm. The mean pupil diameters of awakening infants (200 1ux) and in bright light stimulation were 3.1mm and 2.1mm respectively. All the cases had the response to light stimulation and the mean net miosis was 1.0mm. Anisocoria of 0.5mm to 1.0mm was detected in 11 infants (16%). Thus it may be warranted that the careful investigation to search for neurologic abnormalities is necessary if the pupil size of the neonate is more than 2 standard deviation from the mean (smaller than 1.7mm or larger than 4.5mm in dim illummation), or if their pupils do not respond to light challenge.