Evaluation of choroidal thickness in Malay children with myopia

INTRODUCTION: This study aims to evaluate the choroidal thickness and its correlation with age, spherical equivalent, and axial length in Malay children with myopia, addressing the limited data available on this topic in Southeast Asia.

MATERIAL AND METHODS: A cross-sectional, hospital-based study was conducted from 2022 to 2024 at Hospital Shah Alam and Hospital Pakar Universiti Sains Malaysia. A total of 109 Malay children aged 7-17 years participated, including 88 with myopia and 21 with emmetropia. Each participant underwent a comprehensive ocular examination, including non-cycloplegic refraction and axial length measurement. Choroidal thickness was assessed using Cirrus SD-optical coherence tomography, with one eye from each subject randomly selected for analysis.

RESULTS: The mean subfoveal choroidal thickness was significantly thinner in myopic children (284.91 μm) compared to emmetropic children (347.62 μm) (p<0.001). Additionally, choroidal thickness varied significantly with the degree of myopia: mild myopia had a mean subfoveal thickness of 319.69 μm, moderate myopia 290.04 μm, and high myopia 225.72 μm, with high myopia showing the thinnest choroid (p<0.001). A significant negative correlation was observed between axial length and subfoveal choroidal thickness, while a positive correlation was found between spherical equivalent and choroidal thickness. No significant correlation was identified between age and subfoveal choroidal thickness.

CONCLUSION: Malay children with myopia exhibit a thinner mean choroidal layer compared to their emmetropic peers, with the thinnest choroid observed in cases of high myopia. This indicates that thinning of the choroidal vasculature occurs with the increase in axial length and worsening severity of myopia.