IOP in myopic children: the relationship between increases in IOP and the development of myopia.

Intraocular pressure (IOP) was measured at yearly intervals, from age 7 to 9 years, in 106 Chinese children. The sample had been selected from newborn children for participation in a growth and nutrition study, and all children remaining in this study took part in the myopia study. As part of an ongoing prospective study to examine factors which may be associated with the development of myopia, IOP was compared according to whether the subjects had become myopic or remained non-myopic during the time-frame of the study. During the course of the study 13 children became myopic. There was no difference in the IOP of the incident compared with control groups at age 7 years. The IOP of the incident group was higher following onset of myopia than it was prior to onset whereas there was no difference in the IOP of the control groups over the same period. A high IOP therefore follows the onset of myopia and cannot cause myopia. It is still unknown whether or how myopia causes a high IOP.