Two-dimensional Ultrasound And Two-dimensional Shear Wave Elastography For Evaluation On Lower Extremity Peripheral Neuropathy In Patients With Type 2 Diabetes Mellitus

Objective:The application of two-dimensional ultrasound and two-dimensional shear wave elastography（2D-SWE）to assess abnormal changes in the lower extremity femoral nerve and saphenous neuropathy of patients with type 2 diabetes mellitus（T2DM）.Methods:60 patients with T2DM who were diagnosed in the Second Affiliated Hospital of Dalian Medical University from November 2021 to April 2022 were enrolled.According to the diagnostic criteria of DPN in Guideline for the prevention and treatment of T2DM in China（2020 edition）,they were divided into group B,T2DM without DPN（hereinafter referred to as non-DPN group）including 30 individuals with16 males and 14 females,an age range of 25-66 years,with an average age of（53.2±8.6）years and group C,T2DM with DPN（hereinafter referred to as DPN group）comprising30 individuals with 14 males and 16 females)and an age range of 36-69 years,with an average age of（56.4±10.4）years.In this study,all participants met the diagnostic criteria for T2DM based on the 2019 guidelines established by the World Health Organization.Exclusion criteria:secondary abnormal glucose metabolism caused by hereditary,toxic and neurotoxic drugs;nerve abnormalities caused by nerve root compression,lumbar spinal stenosis,chronic inflammatory demyelinating neuropathy and other cervical and lumbar diseases;patients with lower limb fracture,surgery,skin injury,etc.who are unable to complete ultrasound examination;other diseases leading to neuropathy such as hypothyroidism,vitamin B₁₂ deficiency,HIV,multiple myeloma,etc.In addition,a group of healthy volunteers（Group A）were selected as the control group,comprising 30 individuals with equal gender distribution（15 males and 15females）and an age range of 18-66 years,with an average age of（49.8±15.0）years.There were no significant differences in age,height,body mass index（BMI）and gender distribution among the groups（P>0.05）.The Resona8 color Doppler ultrasound,produced by Mindray company in China and equipped with an L11-3U linear array transducer with a frequency range of 3-10 MHz,and real-time monitoring software for2D-SWE,was used for the study.The width,thickness,cross-sectional area（CSA）,and circumference of the femoral and saphenous nerves in both lower extremities were measured with two-dimensional ultrasound.The average shear wave velocity（SWV）of the femoral nerve and saphenous nerve of both lower extremities was measured by2D-SWE.Parameters of the left and right lower extremities were compared in each groups,and the above parameters were compared among groups.The correlations between ultrasonographic parameters and laboratory indicators were evaluated,and the independent risk factors of femoral nerve and saphenous nerve SWV were analyzed.Results:There was no significant difference in CSA and SWV of left and right lower extremity femoral nerve and saphenous nerve in each group（all P>0.05）.The width,thickness,CSA and circumference of the femoral nerve and saphenous nerve in the group C were greater than those in the group B and A（all P<0.05）;the thickness,diameter and CSA of the femoral nerve in the group B were greater than those in the group A（all P<0.05）.The width,thickness,CSA and circumference of saphenous nerve in the group B were greater than those in the group A（all P<0.05）.The SWV of the femoral nerve and saphenous nerve in the group C was higher than that in the group B and A（all P<0.05）;the SWV of femoral nerve and saphenous nerve in the group B was higher than that in the group A（all P<0.05）.The CSA of the femoral nerve was positively correlated with FBG,Hb A1c,TG,2-hour postprandial blood glucose（r=0.27-0.67,all P<0.05）.The circumference of the femoral nerve was positively correlated with FBG,Hb A1c and TG（r=0.37-0.64,all P<0.01）.The CSA and circumference of the femoral nerve were negatively correlated with Ig F-1（r=-0.32--0.30,all P<0.05）.The CSA and circumference of the saphenous nerve were positively correlated with FBG（r=0.30-0.34,all P<0.05）.The SWV of the femoral nerve,saphenous nerve was all positively correlated with FBG,TG,2-hour postprandial blood glucose（r=0.34-0.59,all P<0.05）.FBG and TG were independent risk factors of femoral nerve SWV（all P<0.01）.FBG and TG were independent risk factors of saphenous nerve SWV（all P<0.01）.Conclusion:The abnormal changes in lower extremity femoral nerve and saphenous nerve of patients with T2DM can be evaluated by two-dimensional ultrasound and 2D-SWE non-invasively,objectively and accurately,which has crucial clinical significance for the early diagnosis,treatment of DPN and for evaluating the efficacy of intervention measures.