ABSTRACT
@#【Objective】To observe macular choroidal thickness and topographical variation in Chinese healthy and myopic children and to investigate the correlated factors. 【Methods】 A total of 196 myopic children treated at Hainan Province Eye Hospital were selected and divided into hyperopia ，emmetropia，low，moderate and severe myopia groups according to their spherical equivalents（SE）. Axial length（AXL），subfoveal choroidal thickness（SFCT）and 1 mm ，3 mm nasal，temporal，superior，and inferior to the foveal choroidal thickness were recorded. Forty- five students from Tung Wah Group of Hospital′s MA Kam Chan Memorial Primary School in Hong Kong were also recruited in this 1-year longitudinal study. Children were grouped to myopic group and emmetropic or hyperopic group according to SE ，thickness changes of choroid were compared among children with or without myopic shift. The correlation among choroidal SE，and AXL variations were also investigated.【Results】Mean SFCT was 250（204~314）μm. The choroid was thinner at the nasal and inferior sectors ，the thinnest being at 3mm nasal to the fovea ，and the thickest at 1mm temporal to the fovea. Choroidal thickness in all orientations became thinner with progressively descending refractive degree. SFCT and 1 mm around fovea decreased most compared with other surrounding directions in all groups（Kruskal- Wallis test，P < 0.05）. The choroidal thickness in subfovea and other sectors got thinned after 1 year follow-up time（Pair t test，P < 0.05）.The variation of the choroidal thickness in fovea and surrounding positions was positively correlated with the change of SE and negatively related to the change of the AXL. The myopic group had a faster descent of SE and a faster growth of AXL than the emmetropic or hyperopic group. SFCT and surrounding choroidal thickness showed a progressive descent in the myopic group，but a slight decrease in the emmetropic or hyperopic groups.【Conclusions】There is significant topographic variation of choroidal at different regions of the macular. The choroidal thickness decreases faster in myopes. SFCT is more sensitive to myopic progression compared with surrounding regions.