糖尿病周围神经病变早期诊断的MR神经成像的研究

糖尿病周围神经病变(DPN)是糖尿病（DM）常见的慢性并发症之一，是DM患者致残、致死的重要原因。其主要病理变化是神经纤维髓鞘节段性或弥漫性皱缩或脱髓鞘，神经纤维轴突变性、消失。目前研究表明这一改变与神经微循环障碍造成神经缺血密切相关，而神经缺血首先出现在下肢近端即坐骨神经水平，并由近端至远端逐渐积累，出现临床症状。迄今为止，对DPN的诊断主要依靠病史、症状及体征、神经电生理检查、定量感觉检查、皮肤活检等。但这些方法均无法直接评价坐骨神经，不能对DPN作出早期诊断。本课题拟利用MR神经成像技术（DTI、DW-MRN、SHINKEI），开展DPN动物模型及DPN患者、无周围神经病变糖尿病患者、正常志愿者坐骨神经的研究，定量分析并随访坐骨神经ADC、FA值的变化及形态学改变，探讨ADC 、FA 值早期诊断DPN的阈值及其与DPN损害程度的相关性，为 DPN的早期诊断提供可靠的影像学指标。

Diabetic peripheral neuropathy (DPN) is one of the most common complications of diabetes mellitus (DM), and is a major cause of morbidity and mortality of DM patients. The main pathologic changes of DPN is segmental or diffuse shrinking or demyelination of nerve fiber, with the degeneration and loss of nerve fiber axonal. At present, the research shows that this change is closely related to neurological ischemic change induced by nerve microcirculation insults, and the microstructure changes first appear in the lower extremities proximal sciatic nerve level, accumulating from proximal to distal and eventually leading to the occur of clinical symptom. The clinical diagnosis of DPN is mainly based on clinical history, symptoms and signs, electrophysiology, quantitative sensory testing (QST), and skin biopsies and so on. However, these methods are unable to directly evaluate the sciatic nerve and make early diagnosis of DPN. Our research plans to utilize magnetic resonance neuropathy technology（DTI、DW-MRN、SHINKEI）to carry out the research in sciatic nerve of the DPN animal models、patients with DPN、patients with diabetes but no DPN and normal volunteers, to quantitatively analysis and follow-up the change of ADC and FA values and morphology of sciatic nerve , exploring the threshold value of ADC and FA value in early diagnosis of DPN and its correlation with the degree of DPN damage, providing reliable imaging indicators for the early diagnosis of DPN.