Clinical Value Of High Frequency Ultrasound And Shear Wave Elastography In The Diagnosis Of Carpal Tunnel Syndrome

OBJECTIVE:To evaluate the role of high-resolution ultrasonography(HRUS)and shear wave elastography(SWE)in carpal tunnel syndrome(CTS)compared to electrodiagnostic testing(EDT)and to explore the correlation between indexes of the HRUS and SWE and the severity of electrophysiological.METHODS:This study enrolled 37 patients with idiopathic CTS(68 CTS hands)and 37 healthy subjects(74 normal hands).Median nerve cross-sectional area(CSA),Young’s Modulus(YM)and shear wave velocity(SWV)at two different levels,the interior of carpal tunnel closed to pisiform bone level(Group 2)and on forearm area away from tunnel inlet of 0.5～1.0cm(Group 1),were measured.Receiver operating characteristic(ROC)curves were plotted for the optimal cut-off values as well as the sensitivity and specificity.Then,comparisons among HRUS、SWE and EDT were made.RESULTS1.The CSA,YM and SWV of MN in the CTS group are significantly higher than those of the control group(p<0.05).The results show that six parameters—CSA1,E1mean,V1mean of Group1 and CSA2,E2min,V2min of Group2,have high diagnostic efficiency,AUC was 0.990,0.748,0.740,0.949,0.859 and 0.859 respectively.When CSA1,E2min and V2min of MN were 8.5mm2,173.60 kPa and 7.59m/s respectively,the sensitivity(100%,85%,85%)and specificity(89%,76%,76%)of diagnosing CTS were the highest.2.The efficiency of the combination of HRUS and SWE(AUC=0.992)is higher than that of single technology,but there was no significant statistical difference(p>0.05).3.CSA1 and CSA2 have significant statistical differences between mild to moderate and severe groups,which can be used to judge the severity of CTS patients(p<0.05).4.In the CTS group,CSA1 was positively correlated with CSA2,E2min and V2min significantly(p<0.05),a negative correlation between CSA1 and E1mean,but there was no significant difference(p>0.05).CSA2 was positively correlated with CSA2,E2min and V2min significantly(p<0.05),a negative correlation between CSA1 and E1mean,but there was no significant difference(p>0.05).CONCLUSIONS:HRUS and SWE are effective and noninvasive methods for the diagnosis of CTS.CSA can also be used as auxiliary diagnostic index for severity classification,and is feasible in clinical application.The best measurement section of CSA in the diagnosis of CTS is the proximal end of carpal tunnel,while the best measurement section of SWE is the internal part of carpal tunnel,and there is no significant difference between SWV and YM in the diagnosis efficiency of CTS,the hardness of MN is related to the degree of swelling.The diagnostic efficiency of combination of HRUS and SWE is higher than that of single technology,which may provide reliable basis for CTS diagnosis.