Abstract: Background　One of the major causes for disability in patients with T2DM was low extremity artery problem.It was very important for decreasing the incidence of diabetic foot and slowing down the development to early detect vascular disease in patients with T2DM.High frequency ultrasound probe could clearly demonstrate the superficial vascular structures and be used to quantitatively analysis of small artery stenosis.Objective　To explore the value of high frequency ultrasound to predict the occurrence of diabetic foot in T2DM,we examinated the dorsal artery in patients with T2DM using 18 MHz high frequency color Doppler ultrasound.Methods　A total of 240 patients with T2DM were involved in this study,which accepted routine examination in Huinan Community Health Service Center of Pudong New District of Shanghai city from January 2014 to June 2015.The patients were divided into diabetic foot group（69 cases） and T2DM group（171 cases） according to whether they had diabetic foot or not.The medical history and laboratory tests of the patients were collected,including inflammatory markers,blood glucose and lipid levels.The dorsal artery diameter（ZBD）,intima-media thickness（IMT）,blood flow,end diastolic velocity（EDV）,peak systolic velocity（PSV） and pulsatility index（PI） were measured and calculated using 18 MHz high frequency color Doppler ultrasound.Results　The difference of the diabetes duration,the levels of WBC,CRP,HbA1c,and 2 hPG were statistically significant（P<0.05） between the two groups.The difference of ZBD，IMT,blood flow and EDV were not statistically significant（P>0.05） between the two groups.The PSV and PI in diabetic foot group were lower than those in T2DM group（P<0.05）.Then the correlation analysis was performed between the parameters which were statistically different between the two groups,including clinical data and 18 MHz high frequency color Doppler ultrasound indicators.There were no relationship between PSV and diabetes duration,WBC,CRP and 2 hPG（r=-0.314,0.129,0.352,-0.103;P>0.05）.A negative relationship was found between PSV and HbA1c（r=-0.642,P<0.05）.There were no relationship between PI and diabetes duration and 2 hPG（r=0.273，-0.117；P>0.05）.A negative relationship were found between PI and WBC,CRP and HbA1c （r=-0.413,-0.518,-0.307;P<0.05）.The correlation coefficient between PSV and HbA1c was larger.ROC curves were analyzed to evaluate the value of PSV and HbA1c in predicting diabetic foot in T2DM patients.The area under the ROC curve for HbA1c predicting diabetic foot in T2DM patients was 0.683.The HbA1c had a sensitivity of 68.6% and a specificity of 42.4% at a cut-off level of 8.1%.The area under the ROC curve for PSV predicting diabetic foot in T2DM patients was 0.886.The PSV had a sensitivity of 87.1% and a specificity of 76.3% at a cut-off level of 46.34 cm/s.The area under the ROC curve for HbA1c predicting diabetic foot in T2DM patients was lower than PSV，and the difference was statistically significant（Z=2.156,P<0.05）.Conclusion　18 MHz high frequency color Doppler ultrasound has better clinical value in the diagnosis of dorsal foot artery disease in T2DM patients,and can predict the occurrence of diabetic foot.

Key words: Diabetes mellitus,type 2, Diabetic foot, Ultrasonography,Doppler,color, Peak systolic velocity, Hemoglobin A,glycosylated

摘要： 背景　下肢动脉血管病变是造成2型糖尿病（T2DM）患者致残的主要原因之一，通过早期检测T2DM患者血管病变，对降低糖尿病足的发生、发展具有重要的意义。高频超声探头能够清晰显示浅表血管结构，并可用于定量分析小动脉的狭窄程度。目的　通过18 MHz高频彩色多普勒超声检测T2DM患者的足背动脉，探索利用高频超声预测T2DM患者发生糖尿病足的价值。方法　选取2014年1月—2015年6月上海市浦东新区惠南社区卫生服务中心进行常规体检的T2DM患者240例为研究对象，根据是否并发糖尿病足，将患者分为糖尿病足组（69例）和T2DM组（171例）。对患者进行病史采集和实验室检查，包括炎性指标、血糖、血脂水平。采用18 MHz高频彩色多普勒超声检测足背动脉频谱，测量与计算足背动脉直径（ZBD）、内中膜厚度（IMT）、血流量、舒张末期流速（EDV）、峰值流速（PSV）及搏动指数（PI）。结果　两组糖尿病病程、白细胞计数（WBC）、C反应蛋白（CRP）、糖化血红蛋白（HbA1c）、餐后2 h血糖（2 hPG）水平比较，差异均有统计学意义（P<0.05）。两组ZBD、IMT、血流量、EDV比较，差异均无统计学意义（P>0.05）；糖尿病足组患者PSV、PI低于T2DM组（P<0.05）。对两组患者临床资料和18 MHz高频彩色多普勒超声检测指标差异有统计学意义的变量进行相关性分析发现，PSV与糖尿病病程、WBC、CRP、2 hPG无线性相关关系（r=-0.314、0.129、0.352、-0.103，P>0.05），与HbA1c呈负相关（r=-0.642,P<0.05）；PI与糖尿病病程、2 hPG无线性相关关系（r=0.273、-0.117，P>0.05），与WBC、CRP、HbA1c呈负相关（r=-0.413、-0.518、-0.307，P<0.05）。PSV与HbA1c的r值较大，采用ROC曲线评价HbA1c及PSV预测T2DM患者发生糖尿病足的价值。HbA1c预测T2DM患者发生糖尿病足的ROC曲线下面积为0.683，取临界点为8.1%时，灵敏度为68.6%，特异度为42.4%；PSV预测T2DM患者发生糖尿病足的ROC曲线下面积为0.886，取临界点为46.34 cm/s时，灵敏度为87.1%，特异度为76.3%。HbA1c预测T2DM患者发生糖尿病足的ROC曲线下面积小于PSV，差异有统计学意义（Z=2.156,P<0.05）。结论　18 MHz高频彩色多普勒超声对T2DM患者足背动脉病变有较好的临床诊断价值，能够较好地预测糖尿病足的发生。

关键词: 糖尿病, 2型, 糖尿病足, 超声检查,多普勒,彩色, 峰值流速, 血红蛋白A,糖基化