Application Of Shear Wave Elastography In The Evaluation Of The Efficacy Of Extracorporeal Shock Wave Lithotripsy

Objective Through the analysis of the relevant clinical case data collected,patients with urinary stones underwent shear wave elastography(SWE)and non-contrast CT before extracorporeal shock wave lithotripsy(ESWL),and passed the specific situation after the patient’s lithotripsy.To evaluate the value of non-contrast CT scanning and SWE technology in predicting the fragility of stones,and establish an in vitro model to prove whether SWE examination can effectively detect the elastic value of stones,on this basis,further study whether SWE technology can effectively evaluate its efficacy before ESWL treatment,if it is really as hypothetical,SWE can effectively judge the hardness of stones like CT,and can predict the effect of ESWL treatment.That would be a new breakthrough for both patients and clinical research.It provides a reference for the selection of treatment regimens for stone patients in the future clinic.Methods Collect the basic information of patients who came to the urology examination room of Gansu Provincial People’s Hospital for extracorporeal shock wave lithotripsy treatment from September 2021 to October 2022,vitro model of urinary stones was established to verify the feasibility of SWE measurement in urinary stones.SWE and CT are performed in all patients prior to ESWL.The clinical data of 80 eligible ESWL-treated patients were analyzed,B-ultrasound or CT examination is performed four weeks after ESWL,residual stones greater than 4mm or requiring secondary lithotripsy are considered failures,patients were divided into ESWL success and ESWL failure.The database was established with SPSS25.0 statistical software to compare age,sex,body mass index(body mass index,BMI),stone side,stone location,stone size,stone surface area,stone elasticity value,and stone CT value.X~2test,t-test,U-test were used to find out the factors related to treatment success,and Logistic regression analysis was used to find out the most important influencing factors,and the best cut-off value,sensitivity and specificity were measured by ROC curve.Results In this study,a total of 80 patients were included,65 patients were successful in ESWL,and 15 patients were in the failed group,and the classification variables such as the sex of the patient,the side of the stone,the location of the stone,the number of shock waves,the total energy,and the time of lithotripsy were tested for rank and sum,and no difference between the successful group and the failed group was found(P>0.05).There was no difference in age and BMI(P>0.05),and the mean elasticity values of stones(11.83±5.02,median 10.93 in the success group,14.49±5.14,median 16.07 P>0.05)in the failure group(25.83±8.68 in the success group,and 29.43±8.23 P>0.05)in the failure group were not significantly different between the two groups.Stone CT values(833.3±142.5 in the success group,1121±135.0 P<0.01 in the failure group),maximum diameter of stone(10.97±1.88 in the success group,median 11;There were significant differences in the efficacy of ESWL in the failure group(12.8±2.27,median 12.0 P<0.005),stone surface area(success group62.29±23.35,median 63.59;failure group 105.27±30.13,median 97.02 P<0.005).In vitro model experiments,a total of 3"artificial stones"were placed sequentially,and the SWE test results showed that No.1 stone Emean:16.4k Pa,EMax:40.3 k Pa,EMin:3.58k Pa;Stone No.2 Emean:30.72 k Pa,Emax:56.16 k Pa,Emin:1.73 k Pa;Stone 3 Emean:20.55 k Pa,Emax:38.61 k Pa,Emin:8.81 k Pa.Conclusion SWE technique can effectively detect the hardness of kidney stones above10 mm,and although the predictive value of SWE examination on the efficacy of ESWL has not been demonstrated in this study,preliminary studies suggest that the application of SWE in predicting the efficacy of ESWL has some research potential;CT plain scan has a strong predictive value in the assessment of the efficacy of ESWL for kidney stones;stone CT value and CT value and stone surface area are important predictors of stone efficacy in ESWL for kidney stones smaller than 2 cm.For patients with maximum cross-sectional area less than85.56 mm2 and CT value less than 965 HU,ESWL can be considered first.