目的 使用扫频源光学相干断层扫描血管成像技术（swept-source optical coherence tomography，SS-OCTA）观察成年近视患者黄斑区脉络膜厚度和血流特点，并分析厚度与血流的相关变化趋势。 方法 横断面研究。共纳入2023年4月至2023年10月于重庆医科大学附属第一医院眼科屈光门诊就诊的18～36岁成年近视患者共138例138只右眼，所有患者检查屈光状态、眼轴（axial length，AL）等常规眼科项目，根据等效球镜度数（spherical equivalent，SE）将其分为低度近视组（-3D<SE≤-0.5D）、中度近视组（-6D<SE≤-3D）及高度近视组（SE≤-6D）。SS-OCTA用于检查量化黄斑部3 mm×3 mm 范围内平均脉络膜厚度（mean choroidal thickness，MCT）、脉络膜毛细血管层血流灌注面积（choriocapillaris blood flow area，CBFA）、脉络膜血管容积（choroidal vessel volume，CVV），脉络膜血管指数（choroidal vessel index，CVI），比较不同程度近视组间黄斑区MCT及各血流参数的差异，并进行相关变化趋势的分析。 结果 不同程度近视组间，黄斑中心凹、旁中心凹及整个黄斑区3 mm×3 mm 范围内的MCT、CBFA、CVV及 CVI差异有统计学意义，均随着近视程度的加深而降低（P<0.01）；排除混杂因素后的偏相关性分析提示黄斑区MCT、CBFA、CVV及CVI与SE呈正相关性（r=0.457、0.434、0.395、0.401，均P=0.000），与AL呈负相关性（r=-0.470、-0.360、-0.465、-0.468，均P=0.000）；逐步线性回归提示黄斑区MCT随着SE（t=2.459，P=0.015）及CVV的增加而变厚（t=8.632，P=0.000）。 结论 成年近视患者黄斑区脉络膜厚度呈不均一分布，随着近视程度的加深，黄斑区脉络膜厚度和血流降低，脉络膜血流状况密切影响脉络膜厚度；脉络膜可能是近视的一个重要生物标志物，本研究结果有助于揭示近视与脉络膜之间的关系。

Objective To investigate the features and changing trend of choroidal thickness and choroidal vascularity in the macular region of adult patients with myopia by using swept-source optical coherence tomography（SS-OCTA）. Methods A cross-sectional study was conducted among 138 adult patients with myopia（138 right eyes），aged 18-36 years，who attended the outpatient service of Department of Ophthalmology，The First Affiliated Hospital of Chongqing Medical University，from April 2023 to October 2023，and routine ophthalmic examination was performed for all patients，including refractive status and axial length（AL）. According to spherical equivalent （SE），the patients were divided into low myopia group（-3D<SE≤-0.5D），moderate myopia group（-6D<SE≤-3D），and high myopia group （SE≤-6D）. SS-OCTA was used to observe and quantify mean choroidal thickness（MCT），choriocapillaris blood flow area（CBFA），choroidal vessel volume（CVV），and choroidal vessel index（CVI） of the 3 mm×3 mm macular region. MCT and choroidal vascularity parameters were compared between the groups with different degrees of myopia，and their changing trends were analyzed. Results There were significant differences between the groups with different degrees of myopia in MCT，CBFA，CVV，and CVI in the central fovea，the parafovea，and the whole macular region within the 3 mm×3 mm area，which decreased with the increase in the degree of myopia（P<0.01）. After elimination of confounding factors，the partial correlation analysis showed that MCT，CBFA，CVV，and CVI in the whole macular region were positively correlated with SE（r=0.457，0.434，0.395，and 0.401，all P=0.000） and were negatively correlated with AL（r=-0.470，-0.360，-0.465，and -0.468，all P=0.000）. The stepwise linear regression analysis showed that MCT gradually increased with the increase in SE（t=2.459，P=0.015） and CVV（t=8.632，P=0.000）. Conclusion MCT in the macular region shows heterogeneous distribution in adult patients with myopia，and MCT and choroidal vascularity parameters in the macular region decrease with the increase in the degree of myopia，while choroidal vascularity closely affects choroidal thickness. The choroid may be an important biomarker for myopia，and the research findings of this study can help to reveal the association between myopia and the choroid.