Abstract
Purpose:
The plusoptiX photoscreener is able to measure noncycloplegic refraction as well as pupil size and deviation. It is an ideal instrument to measure the magnitude of anisocoria and pupil size in children because both pupils are measured simultaneously. In an initial pilot study an association was noted between pupil size and age. We decided to expand the study to include 1306 children under age 18 to see if these associations were valid and to report the incidence of anisocoria.
Methods:
Retrospecitve medical record review was performed on 1306 children aged <1 to 17 years who had a plusoptiX performed as part of a pediatric ophthalmology examination. The plusoptiX was performed by an orthoptist or ophthalmic technician in dim illumination. Data collected included size of left and right pupils, age, gender, laterality and magnitude of anisocoria.
Results:
80.9% of patients had 0 to 0.4 mm of anisocoria, 16.8% had 0.5 to 0.9 mm, 1.5% had 1.0 to 1.4 mm, and 0.8% had 1.5 or more mm. ANOVA test showed that pupil size and age had a significant relationship (P<0.0001), with older children having larger pupil size. Pupil size of children under age 1 averaged 5.2 mm, increasing to 6.1 mm for children over age 16. Increase in pupil size levels off around age 10, and then stays fairly constant through age 17. There is no significant relationship between pupil size and gender (P=0.14). Magnitude of anisocoria appears to increase with age (P=.0073). There is not a significant difference in laterality of anisocoria (P=0.38)
Conclusions:
Pupil size is known to decrease in adults with increasing age; however, there has been little reported on normative data in children. Our study of 1306 children shows that pupil size increases through childhood, beginning to level off at age 10, and that 19.1% of children in a clinic population have anisocoria greater than 0.4 mm.
Keywords: 667 pupil •
463 clinical (human) or epidemiologic studies: prevalence/incidence •
419 anatomy