The Application Of Magnetic Resonance Peripheral Neuroimaging In Type 2 Diabetic Peripheral Neuropathy

Objective:To study the Magnetic resonance imaging(MRI)performance of Tibial nerve and common peroneal nerve in the type 2 diabetic peripheral neuropathy(diabetic peripheral neuropath,DPN)and and discusses the parameters of the DTI applied value in the diagnosis of DPN.Materials and methods:51 cases patients and 32 cases of healthy volunteers were divided into three groups,with diabetes peripheral neuropathy(DPN)group 27 patients,including 12 cases of DPN with axonal injury group and 15 cases of DPN with demyelinating,without diabetes peripheral neuropathy group(NDPN)24 patients and healthy controls(HC)32 cases,MRI scans of the right knee were performed in each group,MRI scanning sequences including knee T1WI,T2WI,T2WI/FS,DWI sequence-MRN can and DTI sequence.Apparent diffusion coefficient(ADC)and Fractional anisotropy(FA)values of the initial length diameter and cross sectional area of the tibial nerve and common peroneal nerve were measured,and observed the changes in the signal and morphology of the tibial nerve and common peroneal nerve in T2WI/FS sequence.DPN group and NDPN group on the right side of the lower extremities of neural electrophysiological examination,record the right knee joint tibial nerve and common peroneal nerve motor nerve conduction velocity(moter nerve conduction velocity,the MCV)and Amplitude of motor nerve conduction,while DPN with peripheral demyelinating lesion was diagnosed with MCV decreased and DPN with axonal injury was diagnosed as MCV reduction accompanied by decreased motor conduction amplitude.Two independent samples t test,Single factor analysis of variance and correlation analysis were used.Receiver operation characteristic(ROC)was used to evaluate the effectiveness of DTI parameters for diagnostic DPN,and the area under the curve and the sensitivity and specificity of diagnostic threshold were recorded.Results:1.HC group,NDPN group and DPN group showed increasing nerve signals on T2WI/FS sequences.2.(1)the cross-sectional area and length-diameter of the tibial nerve and common peroneal nerve in DPN group were larger than those in DPN group,NDPN group and HC group,with statistically significant difference(P<0.05);(2)FA values of tibial nerve and peroneal nerve in DPN group were lower than those in NDPN group and HC group,and the difference was statistically significant(P<0.05);(3)The ADC values of tibial nerve and peroneal nerve in DPN group were higher than those in NDPN group and HC group,and the difference was statistically significant(P<0.05).3.Neuroelectrophysiological examination showed that the conduction velocity and amplitude of the tibial nerve and common peroneal nerve in the DPN group were lower than those in the NDPN group,and the difference was statistically significant(P<0.05).The comparison between DPN group and NDPN group showed that FA value in DTI parameters was positively correlated with MCV and motor nerve conduction amplitude,while ADC value was negatively correlated with MCV and motor nerve conduction amplitude,which was statistically significant.4.ROC curve analysis showed that:(1)the FA diagnostic threshold of DPN tibial neuropathy was 0.386,with a sensitivity of 85%,a specificity of 92.5%and an AUC of 0.933.The diagnostic threshold of ADC for DPN tibial neuropathy was 1.087,with a sensitivity of 80%,a specificity of 82.5%,and an AUC of 0.87.(2)the FA value of DPN was 0.391,with a sensitivity of 85%,a specificity of 82.5%and an AUC of 0.901.The diagnostic threshold of ADC for DPN was 1.099,with a sensitivity of 85%,a specificity of 87.5%,and an AUC of 0.879.5.(1)the cross-sectional area and length-diameter of the tibial nerve in the DPN group with axonal injury were larger than that in the DPN group with demyelinating lesion,and the difference was statistically significant(P<0.05).(2)FA values of the tibial nerve and common peroneal nerve in the DPN group with axonal injury were lower than those in the DPN group with demyelination,while ADC values were higher than those in the DPN group with demyelination,with statistically significant difference(P<0.05).Conclusion:MRI peripheral neuroimaging can show different types of pathological changes in DPN.DTI multi-parameter quantitative analysis of peripheral nerves is helpful in differentiating DPN axonal injury from demyelinating lesion,and can be used for the diagnosis and severity evaluation of diabetic peripheral neuropathy.