Choroidal and Retinal Thickness in Children with Different Refractive Status Measured by Swept-Source Optical Coherence Tomography

Abstract Purpose To investigate the choroidal and retinal thickness in myopic, emmetropic, and hyperopic Chinese children by swept-source longer-wavelength optical coherence tomography. Design Cross-sectional study. Methods Two-hundred-and-seventy-six school children aged 7−13 years underwent comprehensive ophthalmic examinations, including cycloplegic refraction, and swept-source optical coherence tomography measurements. The thickness of the choroid, retina, ganglion cell layer, and nerve fiber layer were compared among children of different refractive status. The topographic variation and factors related to the thickness of the choroid and retinal layers were analyzed. Results Compared to emmetropes, myopes had a significantly thinner choroid in all regions (p < 0.01), and hyperopes had a thicker choroid in most regions (p < 0.05). The myopic retinas were thinner than those of emmetropes or hyperopes in the superior parafoveal and all four perifoveal subfields (p < 0.05), but no other subfields differed significantly among different refractive groups (p > 0.05). The axial length and refractive diopters were independently related to central foveal choroidal thickness (R2 = 0.17, p < 0.01), while age and intraocular pressure were independently associated with central fovea retinal (R2 = 0.15, p < 0.01) and ganglion cell layer thicknesses (R2 = 0.10, p < 0.01) after adjustment for other systematic and ocular factors. Central foveal choroidal and retinal thickness were unrelated in children of different refractive status (p > 0.05). Conclusions Choroidal thickness, but not retinal thickness, correlated closely with axial length and refractive diopters in Chinese children. Choroid thinning occurs before retina thinning early in myopic progression.