Study On The Value Of High Frequency Ultrasound And Shear Wave Elastography In Early Diagnosis Of Guillain-Barré Syndrome

Objective: High frequency ultrasound(HFUS)and Shear wave elastography of peripheral nerves in patients with early Guillain-Barre syndrome(GBS)were observed.To explore the effective indicators of HFUS and SWE in the diagnosis of early GBS,and to explore the clinical diagnostic value of HFUS and SWE in the early stage of GBS.Methods: In this study,27 patients with GBS who visited the Affiliated Hospital of Jining Medical College from October 2021 to February 2023 were recruited as lesion group.The patients met the diagnostic criteria of "Chinese Guidelines for the Diagnosis of GuillainBarre Syndrome(2019)",and did not receive plasma exchange or hormone therapy within 2 weeks of onset.Age matched healthy subjects30 cases as control group.High-frequency ultrasound and shear wave elastic imaging were performed on all subjects.Morphological,echo and color elastic distribution changes of bilateral C6 nerve roots,median nerve and tibial nerve were recorded.Peripheral nerve cross-sectional area and shear wave velocity were measured at predetermined measurement sites.Results: A total of 27 GBS patients and 30 healthy control patients were enrolled in this study.The affected nerve’s high-frequency ultrasound showed blurred echo of the outer nerve membrane,the uneven echo of the nerve bundle decreased and expanded,and the "sieve" structure was blurred or even disappeared.The shear wave elastic diagram of the region showed mainly light yellow and light green,occasionally mixed with some red,uneven distribution.Compared with the control group,the cross-sectional area and shear wave velocity in most ganglia of GBS patients were increased,and the thickening of C6 nerve roots was the most significant.Based on the maximum entry index,bilateral C6 nerve root CSA and SWV were suitable for the early diagnosis of GBS.The optimal cut-off value of the right C6 nerve root CSA was 11mm2,the sensitivity was 59.26%,and the specificity was 96.67%.The best cutoff value of the left CSA was 10mm2,the sensitivity was 66.67%,and the specificity was 90.00%.The optimal truncation value of SWV in the right C6 nerve root was 3.56m/s,the sensitivity was 77.78%,and the specificity was 80.00%.The optimal truncation value of SWV in the left C6 nerve root was 3.56m/s,the sensitivity was 70.37%,and the specificity was 90.00%.The AUC value of bilateral wrist SWV was higher than that of CSA at the same parts,and the difference was statistically significant(P < 0.05).CSA and SWV values in bilateral C6 nerve roots and median nerves(middle upper arm,middle forearm)in acute demyelinating polyneuropathy(AIDP)group were significantly higher than those in the control group.The SWV values of bilateral median nerve(wrist)were different,but there was no significant difference in CSA values.acute motor and sensory axonal neuropathy(AMAN)/acute motor and sensory axonal neuropathy(AMSAN)group compared with the control group,bilateral C6 nerve roots and left tibial nerve(popliteal fossa)CSA and SWV differences,bilateral median nerve(middle upper arm,middle forearm,wrist),bilateral tibial nerve(medial malleolus)and right tibial nerve(popliteal fossa)SWV differences but no significant difference in CSA.Conclusion: High-frequency ultrasound can clearly show the peripheral nerve echo and morphological changes in patients with GBS,and the increase of multi-segmental CSA is helpful for early identification of patients with GBS.SWV can not only effectively evaluate the changes of nerve elasticity in patients with GBS,but also indicate the abnormal changes of nerve elasticity in normal segments of CSA.SWV has good diagnostic efficacy and can be used as the imaging basis for clinical diagnosis of GBS.The imaging findings of different ganglia were inconsistent,with the C6 nerve roots being the most significant in the early stages of the disease.