Study On Diagnostic Value Of Acoustic Radiation Force Impulse Elastography To Breast Solid Nodules

Objective: In recent years,the morbidity of breast tumor has been gradually rising,which seriously threatens women's physical and psychological health.Ultrasonic testing has been an important measure for the diagnosis and screening of malignant breast tumor with several advantages.Acoustic radiation force impulse(ARFI)elastography is an ultrasonic elastography technology that calculates the speed of lateral shear wave of local tissue after distortion,and makes quantitative determination for the tissue hardness by ultrasonic probe transmitting low-frequency impulse.This study applies ARFI elastography to perform elastic quantitative research on breast solid nodules,and further to discuss the diagnostic value of this technique in diagnosis of breast solid nodules.Methods:1 Object of studyThe patients examined by breast ultrasonography with the application of ARFI elastography and from whom we obtained pathologic analysis result by surgery or needle biopsy in the Third Hospital of Xingtai in 2016 were selected as the objects.2 Examination methodsThe information such as age,medical history,palpation of patients suffering from breast solid nodules was recorded.The routine two-dimensional ultrasonography was taken to all breast solid nodules and the data were recorded.Color Doppler examination was adopted to observe the blood supply patterns within and around nodules.Virtual touch tissue imaging(VTI)was applied to all nodule masses to obtain VTI elastography graph,and then virtual touch tissue qualification(VTQ)was utilized to successively obtain shear wave velocity(SWV)of interior zone,perimeter zone of nodules,and normal breast tissue at the same depth as nodules.We took the median after five measuers at the same position.The range of VTQ value set by machine was “0~9m/s”,after methodological mistakes of operation were excluded,if there were no explicit data about VTQ value after repeated measures(namely “X.XXm/s”),take VTI imaging as the reference.If the imaging was black,the cystic lesions could be excluded,while VTQ value was recorded as “9m/s”,if it was cystic lesions,VTQ value was recorded as “0m/s” and the case was excluded.The postoperative pathology was recorded while the data were collated.3 Statistical analysisFor all niduses we took postoperative pathologic analysis as the golden standard to analyze whether VTQ values of each pathological type,different sizes,and different depths of breast solid nodules have statistical differences.SPSS24.0 software package was applied for statistical analysis.The mean value ± standard deviation was adopted in the measurement data.It would be considered statistically significant if P<0.05.Results:1 Pathologic analysisAmong 103 breast solid nodules of 79 patients,there were 72 benign nodules,including 53 fibroadenomas,7 adenosis,5 granulomatous lobular mastitis,6 intraductal papillomas and 1 puberty giant fibroadenoma of breast;30 malignant nodules,including 21 invasive ductal carcinomata,5 ductal carcinomata in situ,1 invasive lobular carcinoma,2 diffuse large B-cell lymphomata,and 1 adenoid cystic carcinoma;1 atypical hyperplasia.2 diagnostic efficiency of ARFI TechnologyThe mean VTQ value in interior zone of benign group was(2.53±1.35)m/s,and that of malignant group was(6.85±2.62)m/s,the difference between the two groups was of statistical significance(P<0.01).According to ROC curve,with area under the curve as 0.900 and 3.46m/s of VTQ value as reference value,its sensitivity was 83.9%,specificity was 91.7%,misdiagnosis rate was 8.3%,missed diagnosis rate was 16.1%,and accuracy was 89.3%.P value of McNemar-Bowker test was 1.00,P>0.05,with high diagnosis accuracy.The mean value of SWV ratio of interior zone of benign group and normal glandular tissue at the same depth was 1.76±1.15,while malignant group was 4.93±2.56,the difference between the two groups was of statistical significance(P<0.05).According to ROC curve,with area under the curve as 0.889 and 3.66 of SWV value as reference value,its sensitivity was 74.2%,specificity was 97.2%,misdiagnosis rate was 2.8%,missed diagnosis rate was 25.8%,and accuracy rate was 90.3%.P value of McNemar-Bowker test was 0.109,P>0.05,with high diagnosis accuracy.3 Between both benign group and malignant groupThe age,nodule size(the longest diameter and average diameter),nodule center depth of patients had statistical differences(P<0.05);the distance between nodule and papilla of both groups,and SWV value of normal breast tissue at the same depth of nodule had no statistical differences(P>0.05).4 SWV value correlation within breast solid nodulesThe correlation P value of SWV value within breast solid nodules with the distance to papilla was 0.794,P>0.05,which was of no statistical significance,both of them had no statistical correlation;the correlation P value with the longest diameter of nodules was 0.003,the correlation P value with average diameter of nodules was 0.000,the correlation P value with central depth of nodules was 0.000,which had statistical correlation.5 The comparison of SWV value within breast solid nodules of different pathologiesSWV value within breast solid nodules was ranked and divided into 3 grades from big to small,among them the 1st grade was invasive ductal carcinoma,the 2nd were intraductal carcinoma in situ and granulomatous lobular mastitis,while the 3rd were intraductal papilloma,adenoma fibrosum and adenosis,based on their sequence of hardness from hard to soft.Conclusion:ARFI elastography is a new non-assistant technology of elastic ultrasound,which is able to offer the information about qualitative and quantitative hardness of tissue.The elastic quantitative measure for the region of interest based on routine ultrasound examination would be less influenced by external and subjective factors with good repeatability,which has great clinical value on the diagnosis of breast solid nodules.This study considers that the key of applying VTQ technology lies in the correct operation.Measure the SWV value within and around nodules,and also of the normal breast tissue at the same depth,with 3.46 m/s of VTQ value within nodules as the reference value;Calculate the SWV ratio within nodules and the normal breast tissue at the same depth with 3.66 as the reference value,so as to take differential diagnosis of benign and malignant breast solid nodules.The limitations of this study:because of the diversity of breast pathology and the cases of some pathological types were too few,this technology is not consistent enough.Therefore,in order to improve the diagnostic accuracy,a variety of methods as well as clinical performance should be combined.For some suspicious lesions,puncture biopsy is needed.