重度非增生型糖尿病视网膜病变患眼黄斑区及视盘血流密度和中心凹无血管区面积观察

The flow density of macular and optic disc and area of foveal avascular zone in severe nonproliferative diabetic retinopathy

目的观察重度非增生型糖尿病视网膜病变(S-NPDR)患眼黄斑区、视盘血流密度和中心凹无血管区(FAZ)面积。方法前瞻性横断面研究。2019年10月至2020年4月于江苏省人民医院眼科确诊为S-NPDR的25例患者31只眼(S-NPDR组)和同期年龄、性别匹配的健康志愿者30名30只眼(对照组)纳入研究。采用光相干断层扫描血管成像(OCTA)对受检眼黄斑区6 mm×6 mm、视盘4.5 mm×4.5 mm范围进行扫描。软件自动将黄斑中心凹6 mm范围内视网膜划分为以黄斑中心凹为中心的3个同心圆,分别是直径为1 mm的中心凹区,1~3 mm的旁中心凹区,3~6 mm次旁中心凹区;将视盘周围(盘周)划分为鼻上、鼻下、下方鼻侧、下方颞侧、颞下、颞上、上方颞侧、上方鼻侧等8个区。测量黄斑区视网膜浅层毛细血管层(SCP)、深层毛细血管层(DCP)和视盘血流密度以及FAZ面积。S-NPDR组、对照组受检眼之间血流密度、FAZ面积比较采用独立样本t检验;FAZ面积与血流密度相关性采用Pearson相关性分析。结果旁中心凹区、次旁中心凹区,S-NPDR组、对照组受检眼间SCP(t=6.470、5.220,P<0.001)、DCP(t=7.270、7.370,P<0.001)血流密度比较,差异均有统计学意义;中心凹区,与对照组比较,S-NPDR组患眼DCP血流密度差异有统计学意义(t=2.250,P=0.030),SCP血流密度差异无统计学意义(t=0.000,P=0.900)。S-NPDR组患眼FAZ面积大于对照组,差异有统计学意义(t=2.390,P=0.030)。S-NPDR组患眼视盘整体、盘周整体及除上方鼻侧外的盘周其他区域血流密度均低于对照组,差异有统计学意义(t=7.520、5.000、4.870、3.120、2.360、2.120、5.410、5.560、2.640,P<0.05)。Pearson相关性分析结果显示,S-NPDR患眼FAZ面积与SCP血流密度呈负相关(r=-0.513,P=0.004),与DCP血流密度无相关性(r=0.034,P=0.859)。结论S-NPDR患眼黄斑区及视盘总体血流密度降低,FAZ面积扩大。

Objective To observe the flow density(FD)of macular and optic disc and area of foveal avascular zone(FAZ)in severe nonproliferative diabetic retinopathy(S-NPDR).Methods A prospective cross-sectional study.From October 2019 to April 2020,31 eyes of 25 S-NPDR patients(S-NPDR group)who were diagnosed in the ophthalmological examination of Jiangsu Province Hospital and 30 eyes of 30 age-and sex-matched healthy volunteers(control group)were included in this study.Optical coherence tomography angiography(OCTA)was used to scan the macular area of 6 mm×6 mm and optic disc of 4.5 mm×4.5 mm.The software automatically divides it into three concentric circles centered on the macular fovea,which were foveal area with a diameter of 1 mm,parafoveal area of 1 to 3 mm,and foveal peripheral area of 3 to 6 mm.The area around the optic disc was divided into 8 areas:nasal upper,nasal lower,inferior nasal,inferior temporal,temporal lower,temporal upper,superior temporal and superior nasal.The FD of the optic disc,the superficial capillary layer(SCP)and deep capillary layer(DCP)of the retina and FAZ area were measured.The FD and FAZ area were compared between the two groups by independent sample t test.The correlation between FAZ area and FD was analyzed by Pearson correlation.Results In parafoveal and perifoveal area,compared with the control group,the FD of SCP(t=6.470,5.220;P<0.001)and DCP(t=7.270,7.370;P<0.001)decreased in S-NPDR group.In foveal area,there was statistically significant difference in the FD of DCP between the two groups(t=2.250,P=0.030),while the difference in FD of SCP between the two groups was not statistically significant(t=0.000,P=0.900).The FAZ area in S-NPDR group was larger than that in control group,and the difference was statistically significant(t=2.390,P=0.030).The FD in the S-NPDR group was lower than that in the control group except the superior nasal,the difference was statistically significant(t=7.520,5.000,4.870,3.120,2.360,2.120,5.410,5.560,2.640;P<0.05).Pearson correlation analysis showed that the FAZ area of S-NPDR was negatively correlated with FD of SCP(r=-0.513,P=0.004),and had no correlation with FD of DCP(r=0.034,P=0.859).Conclusion The overall FD in macular area and optic disc of patients with S-NPDR decreased and the FAZ area enlarged.