目的：探讨并发糖尿病视网膜病变(DR)的2型糖尿病患者与健康人群脉络膜血管指数(CVI)的差异及特点。

方法：选取2017-01/12于我院就诊的并发DR的2型糖尿病患者68例68眼作为DR组，同时纳入同期体检的无糖尿病病史健康人群34例34眼作为对照组。通过频域相干光层析深度增强成像术(EDI-OCT)获取受检者黄斑中心凹下脉络膜厚度(SFCT)、黄斑中心凹处视网膜厚度(CRT)，并将黄斑区图像进行二值化处理，采用图像分析软件计算黄斑区脉络膜总面积(TCA)、血管区面积(LA)及间质区面积(SA)，计算CVI。

结果：对照组和DR组受检者TCA(0.53±0.14mm² vs 0.49±0.15mm²)、LA(0.35±0.09mm² vs 0.32±0.10mm²)、SA(0.17±0.05mm² vs 0.17±0.06mm²)及SFCT(347.9±76.9μm vs 325.9±92.9μm)均无差异(P>0.05)，但DR组患者CVI明显低于对照组(64.33%±3.25% vs 67.04%±2.46%，P<0.001)，二者临界值为63.59%。

结论：CVI可以直观反映脉络膜内部结构的变化，较SFCT更加稳定可靠，合并DR的2型糖尿病患者其CVI较健康人群降低。

METHODS: A retrospective cross-sectional study was performed at Beijing Friendship Hospital. Enhanced depth imaging spectral-domain optical coherence tomography(EDI-OCT)scans of 68 eyes of 68 type 2 diabetes who with diabetic retinopathy were compared with those of right eyes of 34 age- and gender-matched healthy controls. The choroidal images were binarized into luminal areas(LA)and stromal areas(SA). CVI was defined as the ratio of LA to total circumscribed subfoveal choroidal area. Mean choroidal thickness, mean retinal thickness and mean CVI between patients and controls were compared using t-test.

RESULTS: There were no significant differences in total circumscribed subfoveal choroidal area(0.53±0.14mm² vs 0.49±0.15mm²), LA(0.35±0.09mm² vs 0.32±0.10mm²), SA(0.17±0.05mm² vs 0.17±0.06mm²), or subfoveal choroidal thickness(347.9±76.9μm vs 325.9±92.9μm)between patients with DR and controls(P>0.05). However, there was a significantly lower CVI in patients with diabetes as compared to controls(64.33%±3.25% vs 67.04%±2.46%, P<0.001). The critical value was 63.59%.

CONCLUSION: CVI is a kind of biological indicators which can directly reflect the changes of choroidal internal structure, and it is more stable and reliable than SFCT. For type 2 diabetic patients who with diabetic retinopathy, CVI is lower than that of healthy people.