糖尿病大鼠模型坐骨神经SWE与病理早期改变相关性研究

Correlation Between SWE of Sciatic Nerve and Early Pathological Changes in Diabetic Rats

目的通过剪切波弹性成像(Shear Wave Elastography,SWE)技术评估大鼠糖尿病周围神经病变(Diabetic Peripheral Neuropathy,DPN),探讨DPN组织学与SWE的相关性,为深入了解DPN基础、临床早诊及干预提供影像学依据。方法腹腔注射链脲菌素溶液(左下腹单次55 mg/kg)建立糖尿病大鼠模型(11只)为DPN组,另10只作为对照组,建模成功2周后记录比较2组大鼠的坐骨神经SWE各参数;坐骨神经组织HE染色及透射电镜观察其病理改变。Image J软件对电镜图片进行定量分析(每组随机选取4只),比较2组间神经髓鞘的外周周长、内周周长、横截面积及平均厚度。结果与对照组比较,DPN组建模2周后即出现SWE参数增高(P<0.05);ROC曲线分析提示病变的预警值:Emean为14.90 kPa、Emax为16.55 kPa、Vmean为2.15 m/s。光镜观察DPN组大鼠神经髓鞘明显肿胀,透射电镜示DPN组髓鞘板层崩解,分离明显,结构紊乱;对照组与DPN组定量分析相比,髓鞘外周周长、横截面积、平均厚度间均存在显著差异(P<0.05)。结论糖尿病大鼠发病2周时SWE即可提示神经早期病变,组织学亦有变化,SWE参数改变与其病理学基础变化具有一定相关性,SWE有望为临床及时发现DPN、稳定控制DPN并发症提供早期影像学依据。

Objective To evaluate the diabetic peripheral neuropathy(DPN)in diabetic rats by shear wave elastography(SWE),and to explore the correlation between DPN histology and SWE,so as to provide imaging basis for in-depth understanding of pathology,early clinical diagnosis and intervention of DPN lesions.Methods Diabetic rat models(n=11)were established by intraperitoneal injection of streptozotocin solution(55 mg/kg in left lower abdomen)as DPN group,and the other 10 rats were used as control group.After two weeks of successful modeling,the SWE parameters of sciatic nerve of rats in the two groups were recorded and compared.The pathological changes of sciatic nerve were observed by HE staining and transmission electron microscope.Image J software was used for quantitative analysis of the electron microscope images(4 rats were randomly selected in each group),and the peripheral perimeter,inner perimeter,cross-sectional area,and average thickness of the myelin sheath were compared between the two groups.Results Compared with the control group,the SWE parameters in the DPN group increased at two weeks after modeling(P<0.05);the receiver operating characteristic curve indicated that the early warning values of neuropathy:Emean was 14.90 kPa,Emax was 16.55 kPa,and Vmean was 2.15 m/s.The nerve myelin sheath of the rats in the DPN group was obviously swollen under light microscope,and the transmission electron microscope showed that the myelin sheath was disintegrated with obvious separation and structural disorder in the DPN group.There were significant differences in peripheral perimeter,cross-sectional area and average thickness of myelin sheath between the two group(P<0.05).Conclusion SWE can indicate early neurological lesions in diabetic rats two weeks after onset,and histological changes are also occur.The changes of SWE parameters have a certain correlation with the basic pathological changes.SWE is expected to provide early imaging basis for timely detection of DPN and stable control of DPN complications.