Distribution of intraocular pressure in healthy Iranian children: the Shiraz Pediatric Eye Study

Abstract

PurposeTo describe the mean and normal range of intraocular pressure (IOP) and its associations in healthy Iranian school children using the noncontact tonometer. MethodsIn this cross-sectional study as part of the Shiraz Pediatric Eye Study, a stratified random sampling was performed among elementary school children of Shiraz, Iran. Basic demographics and socioeconomic status of households, past medical history, drug history, and eye health history were collected for each eligible student. Children underwent complete ophthalmic examination. Axial length, corneal curvature, and anterior chamber depth were measured using the IOL-Master 500. ResultsOf 2,001 eligible children, 1,901 (95.0%; 3,802 eyes) with a mean age of 9.1 ± 1.6 years (standard deviation; range, 6-12 years) had reliable IOP. The mean spherical equivalent refraction was 0.5 ± 1.3 D for the right eye and 0.6 ± 1.2 D for the left eye. Mean IOP in the right eye was 15.1 ± 2.5 mm Hg (median, 15.0; range, 8.0–27.0 mm Hg); in the left eye, 15.2 ± 2.5 mm Hg (median, 15.0; range, 9.0–28.0 mm Hg). In multiple regression analyses, the mean IOP was significantly lower among asthmatic children compared to normal participants (P = 0.007). The measured IOP was significantly higher in myopic participants than hyperopic patients (P = 0.003). ConclusionsThis study provides a useful normative IOP database using the noncontact tonometer for healthy Iranian school children.