Pupillary evaluation can be a critical element in physical exams. As such, researchers from Chicago found sex and age may play a role in scotopic pupillary size and function in children.

Their study, published in the British Journal of Ophthalmology, found boys had greater maximum constriction velocity and constriction percentage compared with girls, and age was tied to maximum and minimum diameters and constriction percentages.

The investigation included 196 eyes of 101 normal participants younger than 18 who were seen at Lurie Children’s Ophthalmology in Chicago. The researchers analyzed pupillometry findings such as maximum and minimum diameters, constriction percentage, latency average, maximum constriction velocities, average dilation velocity and 75% recovery time.

The study found the following:

• Overall, maximum diameters were 6.6mm while minimum diameters were 4.7mm.
• The constriction percentage was 30%.
• Latency was was 230 milliseconds.
• Average constriction velocity was 3.70mm/sec, while average dilation velocity was 0.88mm/sec.
• Age was positively tied to maximum and minimum diameter and constriction percentage.
• 84.2% and 95.8% of participants showed resting pupil asymmetry of 0.5mm or less and 1mm or less, respectively.

Quantitative pupillometry can be a useful tool for screening pediatric patients, the researchers said. This study is the first to propose normative values for parameters of scotopic pupillary function in a pediatric population in typical clinical conditions, they added.