Corneal Hyterei and Axial Length Among Chinee econdary chool Children: The Xichang Pediatric Refractive Error tudy (X-PRE) Report No. 4 Original Reearch Article

Purpoe To evaluate the aociation between corneal hyterei and axial length/refractive error among rural Chinee econdary chool children. Deign Cro-ectional cohort tudy. Method Refractive error (cycloplegic auto-refraction with ubjective refinement), central corneal thickne (CCT) and axial length (ultraonic meaurement), intraocular preure (IOP), and corneal hyterei (Reichert Ocular Repone Analyzer) were meaured on a rural chool-baed cohort of children. Reult Among 1,233 examined children, the mean age wa 14.7 ± 0.8 year and 699 (56.7%) were girl. The mean pherical equivalent (n = 1,232) wa −2.2 ± 1.6 diopter (D), axial length (n = 643) wa 23.7 ± 1.1 mm, corneal hyterei (n = 1,153) wa 10.7 ± 1.6 mm Hg, IOP (n = 1,153) wa 17.0 ± 3.4 mm Hg, and CCT (n = 1,226) wa 553 ± 33 micron. In linear regreion model, longer axial length wa ignificantly (P < .001 for both) aociated with lower corneal hyterei and higher IOP. Hyterei in thi population wa ignificantly (P < .001) lower than ha previouly been reported for normal White children (n = 42, 12.3 ± 1.3 mm Hg), when adjuting for age and gender. Thi difference did not appear to depend on difference in axial length between the population, a it perit when only Chinee children with normal uncorrected viion are included. Concluion Propective tudie will be needed to determine if low hyterei place eye at rik for axial elongation econdary or if primary elongation reult in lower hyterei.