Study On The Correlation Between Ultrasonic Parameters Of Median Nerve Cross Section Area And Severity Of Carpal Tunnel Syndrome

Objective:The cross sectional area(cross sectional area,CSA)of median nerve at pea bone level was measured by high-frequency ultrasound.The factors affecting the CSA of median nerve at pea bone level were discussed and the correlation between these factors and the cross-sectional area of median nerve at pea bone level was analyzed.Methods:From February 2017 to February 2019,the right wrists of 200 healthy people were selected for clinical symptoms and physical examination except for carpal tunnel syndrome(carpal tunnel syndrome,CTS).The osseous markers of carpal tunnel entrance and outlet are pea bone and hook respectively.The most commonly used assessment index is the median nerve CSA at pea bone level.The CSA,of median nerve of pea bone level was measured by high-frequency ultrasound to evaluate the range of changes of normal values under different influencing factors.The mean values were measured three times repeatedly,and their values were compared with height,body weight and body mass index.Engage in manual labor time and so on to carry on the correlation analysis.Results:The mean mass index(r=0.54,P<0.01)and the mean time of hand labor(r=0.33,P<0.01)were positively correlated with the body mass index(r=0.54,P<0.01).There was no correlation between the height of the subject(r=-0.10,P=0.23),the body weight(r=0.52,P=0.18),and the difference was not statistically significant.Conclusion:The display rate of median nerve under high frequency ultrasound is 100%.There is difference in normal measurement of CSA in different individuals.Measurement of median nerve cross-sectional area at pea bone level can not avoid the influence of individual factors.There was no uniform standard for the diagnosis of carpal tunnel syndrome.The study needs to include more parameters that avoid individual differences to assess carpal tunnel syndrome.Objective:Median nerve cross-sectional area(cross sectional area,CSA)was influenced by body mass index and working time of hand.There was no unified criterion for diagnosis of carpal tunnel syndrome(carpal tunnel syndrome,CTS)with pure median nerve CSA at pea bone level.In this study,the area increment and area ratio were calculated by high frequency ultrasound measurement of CSA,in different parts of CTS patients,and the correlation between the area increment and area ratio and the severity of neuroelectrophysiological examination was discussed,and the threshold for predicting the severity of CTS was obtained.And evaluate it.Diagnostic efficacy.Methods:70 cases(104 wrists)diagnosed as CTS by neuroelectrophysiology were selected.The patients were divided into three groups according to electrophysiological grading criteria:mild group(21),moderate group(48)and severe group(35).The osseous marks of the entrance and outlet of the carpal tunnel are pea bone and hook respectively,and the cross section of the thickest part of the median nerve within the distance is defined as CSAC(carpal tunnel cross-sentional area,CSAC).Selecting the sectional area of the horizontal median nerve of the anterior rotator as CSAP(pranator quadralus mus Cle cross-sentional area,CSAP),the anterior circumflex muscle is a small,thin and flat quadrangular muscle tissue that adheres to the ulnar and radial bones.The cross-sectional area of the median nerve at the level of the anterior circumflex muscle varies little,and the repeated measurements are more repeatable.The difference between CSAC and CSAP cross-sectional area CSA(CSA=CSAC-CSAP)and the ratio of CSAC to CSAP cross-sectional area R-CSA(R-CSA=CSAC/CSAP)were measured by CSAC and CSAP,respectively.And the correlation with electrophysiological results was studied.Results:According to the neuroelectrophysiological diagnosis,the experimental group was divided into three groups:mild,moderate and severe CTS.The area increment CSA and area ratio R-CSA calculated by CSAC and CSAP,were significantly different among the three groups(P<0.01).The average area increment CSA of mild group,moderate group and severe group were(4.5±2.6)mm2,(7.1±2.2)mm2,(10.8±4.6)mm2,respectively.The average area ratio(R-CSA)was 1.4±0.4,1.8±0.5,2.4±0.9,respectively.The critical values of CSA for mild and moderate,moderate and severe CTS were 6mm2 and 9mm2,respectively,with diagnostic specificity of 83.1%and 87.7%,and sensitivity of 79.8%and 62.3%,respectively.The critical values of R-CSA for classification of mild to moderate,moderate and severe CTS were 1.6 and 2.1,respectively.The diagnostic specificity and sensitivity were 78.5%and 84.0%,76.2%and 51.5%,respectively(table 4).Conclusion:The use of CSA and R-CSA in the diagnosis of CTS can avoid the influence of individual differences.The analysis of ROC curve showed that CSA and R-CSA were correlated with the severity of CTS,and the diagnostic efficiency of CSA was better than that of R-CSA.