ABSTRACT
Objective@#Viscoelasticity is an essential feature of nerves, although little is known about their viscous properties. The discovery of shear wave dispersion (SWD) imaging has presented a new approach for the non-invasive evaluation of tissue viscosity.The present study investigated the feasibility of using SWD imaging to evaluate diabetic neuropathy using the sciatic nerve in a diabetic rat model. @*Materials and Methods@#This study included 11 diabetic rats in the diabetic group and 12 healthy rats in the control group.Bilateral sciatic nerves were evaluated 3 months after treatment with streptozotocin. We measured the nerve cross-sectional area (CSA), nerve stiffness using shear wave elastography (SWE), and nerve viscosity using SWD imaging. The motor nerve conduction velocity (MNCV) was also measured. These four indicators and the histology of the sciatic nerves were then compared between the two groups. The performance of CSA, SWE, and SWD imaging in distinguishing the two groups was assessed using receiver operating characteristic (ROC) analysis. @*Results@#Nerve CSA, stiffness, and viscosity in the diabetic group was significantly higher than those in the control group (all p < 0.05). The results also revealed a significantly lower MNCV in the diabetic group (p = 0.005). Additionally, the density of myelinated fibers was significantly lower in the diabetic group (p = 0.004). The average thickness of the myelin sheath was also lower in the diabetic group (p = 0.012). The area under the ROC curve for distinguishing the diabetic neuropathy group from the control group was 0.876 for SWD imaging, which was significantly greater than 0.677 for CSA (p = 0.030) and 0.705 for SWE (p = 0.035). @*Conclusion@#Sciatic nerve viscosity measured using SWD imaging was significantly higher in diabetic rats. The viscosity measured using SWD imaging performed well in distinguishing the diabetic neuropathy group from the control group.Therefore, SWD imaging may be a promising method for the evaluation of diabetic neuropathy.
ABSTRACT
Objective To evaluate the morphological changes of sural nerve in patients with type 2 diabetes mellitus by hyperfrequency ultrasound.Methods Fifty-six sural nerves of symptomatic group,64 sural nerves of asymptomatic group,and 60 sural nerves of control group were identified by 22 MHz Ultrasound.The thickness/width (T/W) ratio,cross-sectional areas (CSA) and the maximum thickness of neuronal fascicles (MT) of the sural nerve were calculated in transverse sonograms.Results ①Ultrasound can clearly show these structures of sural nerve such as epineurium,perineurium and nerve bundles and so on.②In symptomatic group,asymptomatic group and control group,T/W ratio and MT were gradually increased,and the differences among the three groups were statistically significant (P＜0.05).Whereas,there were no statistically significant differences in CSA among the three groups (P=0.257).Conclusions22 MHz ultrasound may be a valuable tool in evaluating the diabetic cutaneous nerve neuropathy