糖尿病视网膜病变视网膜缺血的定量分析及其与糖尿病黄斑水肿的相关性

Quantitative analysis of retinal ischemia in diabetic retinopathy and its correlation with diabetic macular edema

目的利用缺血指数(ISI)定量评估糖尿病视网膜病变(DR)患眼超广角荧光素眼底血管造影(UWFA)图像中不同区域视网膜缺血情况,并分析其与糖尿病黄斑水肿(DME)的相关性。方法采用横断面研究设计,纳入2017年9月至2020年10月于武汉大学人民医院眼科初诊为DR的患者79例79眼,其中男44例44眼,女35例35眼;年龄31~73岁,平均(55.95±8.80)岁,所有患者均行UWFA检查及频域光相干断层扫描(SD-OCT)检查。根据黄斑区OCT图像将患者分为DME组37眼和无DME组42眼。将UWFA检查中期图像分为后极部、中周部、远周部并计算各区域内ISI。应用OCT设备自带软件自动计算黄斑中心凹视网膜厚度(CMT)。采用Spearman秩相关检验分析DME组视网膜各区域ISI与CMT的相关性。结果所有DR患眼全视网膜、后极部、中周部、远周部ISI分别为2.460(0.603,5.640)%、2.670(1.062,9.574)%、1.382(0.245,4.378)%和0.000(0.000,1.262)%,总体比较差异有统计学意义(χ^(2)=65.307,P<0.001);其中全视网膜与远周部、后极部与中周部、后极部与远周部、中周部与远周部ISI比较,差异均有统计学意义(均P<0.01)。DME组患眼全视网膜、后极部及中周部ISI均明显高于无DME组,差异均有统计学意义(U=424.000,P=0.001;U=403.000,P<0.001;U=493.000,P=0.005),2个组眼远周部ISI比较差异无统计学意义(U=609.000,P=0.061)。DME组患眼全视网膜、后极部、中周部及远周部ISI与CMT均无明显相关性(rs=-0.134、-0.018、-0.152、-0.163,均P>0.05)。结论DR眼的视网膜无灌注区主要位于后极部和中周部,且DME患眼后极部及中周部视网膜ISI明显高于无DME患眼。DME患眼视网膜各区域内的ISI均与DME的严重程度无明显相关性。

Objective To quantitatively evaluate the retinal ischemia in different retinal regions of diabetic retinopathy(DR)patients in ultra-widefield fluorescein fundus angiography(UWFA)images with ischemic index(ISI),and to explore its correlation with diabetic macular edema(DME).Methods A cross-sectional study was conducted.Seventy-nine eyes of 79 patients with DR were enrolled in Renmin Hospital of Wuhan University from September 2017 to October 2020,including 44 males(44 eyes)and 35 females(35 eyes)aged 31 to 73 years old,with an average age of(55.95±8.80)years.UWFA and spectral-domain optical coherence tomography(SD-OCT)were performed in all patients.Patients were divided into DME group(37 eyes)and non-DME group(42 eyes)according to the presence or absence of DME in OCT images.The retina in middle phase UWFA images were divided into posterior,middle peripheral and far peripheral regions by ImageJ software,and ISI in each region was calculated.Central macular thickness(CMT)was automatically calculated using the built-in software of the OCT equipment.The correlation between ISI and CMT was analyzed by Spearman rank correlation analysis.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Renmin Hospital of Wuhan University(No.WDRY2019-K037).Written informed consent was obtained from each patient prior to any medical examination.Results The ISI of the total,posterior,middle peripheral and far peripheral retina was 2.460(0.603,5.640)%,2.670(1.062,9.574)%,1.382(0.245,4.378)%and 0.000(0.000,1.262)%,respectively,with a statistically significant difference among different regions(χ^(2)=65.307,P<0.001).There were statistically significant differences in ISI between the total and far peripheral,the posterior and middle peripheral,the posterior and far peripheral,the middle and far peripheral(all at P<0.01).ISI of the total,posterior and middle peripheral retina in DME group were significantly higher than those in non-DME group(U=424.000,P=0.001;U=403.000,P<0.001,U=493.000,P=0.005),but there was no significant difference in the ISI of the far peripheral region between the two groups(U=609.000,P=0.061).There was no statistically significant correlation between ISI and CMT in the total,posterior,middle peripheral and far peripheral retina in DME group(rs=-0.134,-0.018,-0.152,-0.163;all at P>0.05).Conclusions The retinal non-perfusion area in DR eyes is mainly located in the posterior and middle peripheral retina.The ISI of the posterior and middle peripheral retina in DME eyes is significantly higher than that in eyes without DME.ISI of each retinal region may not be related to the severity of DME.