BACKGROUND Shear wave elastography(SWE)is a non-invasive ultrasound-based technique used to assess tissue stiffness,which reflects underlying pathological changes.While SWE has been widely applied for liver fibrosis e...BACKGROUND Shear wave elastography(SWE)is a non-invasive ultrasound-based technique used to assess tissue stiffness,which reflects underlying pathological changes.While SWE has been widely applied for liver fibrosis evaluation,its application to other abdominal organs,such as the spleen and pancreas,is gaining interest.However,normal stiffness values and inter-system agreement remain poorly defined.AIM To assess the feasibility and agreement of liver,spleen,and pancreas stiffness using three SWE methods.METHODS This single-center observational study enrolled 50 healthy adult volunteers.Liver,spleen,and pancreas stiffness were assessed using three SWE methods:Point-SWE(p-QElaXto)and 2-Dimensional-SWE(2D-QElaXto)with Esaote MyLab 9,and 2D-SWE with SuperSonic Imagine.Feasibility,inter-operator reproducibility,and concordance among systems were evaluated.Stiffness was expressed as median kPa values,and technical reliability was assessed using the interquartile range/median ratio and stability index thresholds.RESULTS Liver and spleen stiffness assessment was feasible in>98%of patients,while pancreas stiffness was measurable in 84%-88%depending on the SWE technique.Mean liver stiffness ranged between 3.9-4.7 kPa across techniques,spleen stiffness ranged from 19.4-23.0 kPa,and pancreas stiffness from 5.2-7.6 kPa.Inter-operator agreement was excellent for liver(intraclass correlation coefficient>0.90)and good to moderate for spleen and pancreas(intraclass correlation coefficient from 0.43 to 0.90).Bland-Altman analysis confirmed good correlation but also systematic differences among devices,especially in pancreas measurements.CONCLUSION This is the first study to establish normal liver,spleen,and pancreas stiffness using MyLab 9 SWE integrated methods as compared to SuperSonic Imagine,with acceptable inter-technique agreement.Liver and spleen values matched existing guidelines;pancreas SWE showed more variability and reduced reproducibility.展开更多
Fractures play a crucial role in various fields such as hydrocarbon exploration,groundwater resources management,and earthquake research.The determination of fracture location and the estimation of parameters such as ...Fractures play a crucial role in various fields such as hydrocarbon exploration,groundwater resources management,and earthquake research.The determination of fracture location and the estimation of parameters such as fracture length and dip angle are the focus of geophysical work.In borehole observation system,the short distance between fractures and detectors leads to weak attenuation of elastic wave energy,and high-frequency source makes it easier to identify small-scale fractures.Compared to traditional monopole logging methods,dipole logging method has advantage of exciting pure shear waves sensitive to fractures,so its application is becoming increasingly widespread.However,since the reflected shear waves and scattered shear waves of fractures correspond to different fracture properties,how to distinguish and analyze these two kinds of waves is crucial for accurately characterizing the fracture parameters.To address this issue,numerical simulation of wave responses by a single fracture near a borehole in rock formation is performed,and the generation mechanism and characteristics of shear waves scattered by fractures are investigated.It is found that when the dip angle of the fracture surpasses a critical threshold,the S-wave will propagate to both endpoints of the fracture and generate scattered S-waves,resulting in two distinct scattered wave packets on the received waveform.When the polarization direction of the acoustic source is parallel to the strike of the fracture,the scattered SH-waves always have larger amplitude than the scattered SV-waves regardless of changing the fracture dip angle.Unlike SV-waves,the SH-waves scattered by the fracture do not have any mode conversion.Additionally,propagation of S-waves to a short length fracture can induce dipole mode vibration of the fracture within a wide frequency range.The phenomena of shear waves reflected and scattered by the fracture are further illustrated and verified by two field examples,thus showing the potential of scattered waves for fracture evaluation and characterization with borehole observation system.展开更多
BACKGROUND Thyroid dysfunction during pregnancy is an important disease affecting the health of mothers and children.Two-dimensional(2D)shear wave elastography(SWE)is the newest ultrasonic elastography technology and ...BACKGROUND Thyroid dysfunction during pregnancy is an important disease affecting the health of mothers and children.Two-dimensional(2D)shear wave elastography(SWE)is the newest ultrasonic elastography technology and its value in differentiating benign and malignant thyroid nodules has been widely recognized.However,the value of 2D SWE in evaluating and predicting thyroid function is unclear.AIM To explore prospectively the value of 2D SWE quantitative analysis for the evaluation of thyroid function in the first trimester.METHODS We included outpatients of reproductive age in the Department of Gynecology in Shanghai Changning Maternity and Infant Health Hospital between March 2023 and March 2024 who had conventional ultrasound examination and 2D SWE of the thyroid.They also underwent transvaginal ultrasound examination to confirm early intrauterine pregnancy and serum thyroid stimulating hormone(TSH)level was measured.The patients were divided into pregnant with normal TSH,pregnant with abnormal TSH,and nonpregnant with normal TSH.Conventional ultrasound and 2D SWE results were compared among the three groups.RESULTS A total of 108 patients were included in the study;57 in the pregnant with normal TSH group,18 in the pregnant with abnormal TSH group and 33 were in the nonpregnant with normal TSH group.Thyroid size,thyroid echotexture,2D SWE quantitative parameters including mean elasticity in the region of interest and maximal elasticity in the region of interest showed no significant differences among the three groups(P>0.05).CONCLUSION Conventional ultrasound and 2D SWE features could not reflect the level of serum TSH.展开更多
Endoscopic ultrasound-guided shear wave elastography(EUS-SWE)represents a significant advancement in non-invasive tissue characterization,enabling objective assessment of quantitative tissue stiffness in real-time wit...Endoscopic ultrasound-guided shear wave elastography(EUS-SWE)represents a significant advancement in non-invasive tissue characterization,enabling objective assessment of quantitative tissue stiffness in real-time with potential clinical relevance across a variety of gastrointestinal disorders.Recent developments in EUS-SWE have expanded its application beyond hepatic fibrosis to include pancreatic diseases and the evaluation of solid tumors.EUS-SWE has demonstrated diagnostic accuracy comparable to vibration-controlled transient elastography in assessing fibrosis stages,positioning it as a potential alternative to liver biopsy.Moreover,EUS-SWE has shown promise in evaluating pancreatic tissue stiffness,aiding in the diagnosis and monitoring of chronic pancreatitis and pancreatic cancer.This technique offers a distinct advantage by allowing tissue stiffness measurements during the same procedure,thereby reducing the need for additional imaging studies and biopsies.Despite its clinical potential,challenges remain,including the need for standardized protocols,optimal cutoff values,and validation across diverse patient populations.This minireview provides a comprehensive analysis of the current literature on EUS-SWE,examining its diagnostic performance,reproducibility,and limitations.Furthermore,we discuss the future directions of EUS-SWE,including its integration into routine clinical practice and its evolving role in precision medicine,emphasizing the necessity of large-scale studies to solidify its clinical utility and establish standardized guidelines for its use.展开更多
This study explores the significance of using two-dimensional shear wave elastography(2D-SWE)to assess liver stiffness(LS)and spleen area(SPA)for predicting post-hepatectomy liver failure(PHLF).By providing a non-inva...This study explores the significance of using two-dimensional shear wave elastography(2D-SWE)to assess liver stiffness(LS)and spleen area(SPA)for predicting post-hepatectomy liver failure(PHLF).By providing a non-invasive method to measure LS,which correlates with the degree of liver fibrosis,and SPA,an indicator of portal hypertension,2D-SWE offers a comprehensive evaluation of a patient’s hepatic status.These advancements are particularly crucial in hepatic surgery,where accurate preoperative assessments are essential for optimizing surgical outcomes and minimizing complications.This letter highlights the prac-tical implications of integrating 2D-SWE into clinical practice,emphasizing its potential to improve patient safety and surgical precision by enhancing the ability to predict PHLF and tailor surgical approaches accordingly.展开更多
Using seismic data of the aftershocks sequence of the April 20, 2013 Lushan earthquake recorded by seismic temporary and permanent stations in the source region, with the visual inspection of particle motion diagrams,...Using seismic data of the aftershocks sequence of the April 20, 2013 Lushan earthquake recorded by seismic temporary and permanent stations in the source region, with the visual inspection of particle motion diagrams, this paper preliminarily contains the polarization directions of fast shear wave and the time-delays of split shear waves at every station, and analyzes the crustal anisotropic characteristics in the source region. In the study area, the polarization direc- tions at stations BAX, TQU, L 132, L 133, L 134, and L 135 are northeast, which is consistent with the strike of Dachuan- Shuangshi fault. There are two polarization directions at MDS and L131, which are northeast and southeast. The scatter of polarization directions suggests the complex stress field around these two stations where two faults intersect. For the normalized time-delays at every station, the range is 1.02-8.64 ms/km. The largest time-delay is from L134 which is closest to the mainshock, and the smallest one is from L133. The variations in time-delays show the decreasing at stations BAX, L134, and L135 because of the stress-relaxation after earthquake.展开更多
The Shimian area of Sichuan sits at the junction of the Bayan Har block.Sichuan-Yunnan rhombic block,and Yangtze block,where several faults intersect.This region features intense tectonic activity and frequent earthqu...The Shimian area of Sichuan sits at the junction of the Bayan Har block.Sichuan-Yunnan rhombic block,and Yangtze block,where several faults intersect.This region features intense tectonic activity and frequent earthquakes.In this study,we used local seismic waveform data recorded using dense arrays deployed in the Shimian area to obtain the shear wave splitting parameters at 55 seismic stations and thereby determine the crustal anisotropic characteristics of the region.We then analyzed the crustal stress pattern and tectonic setting and explored their relationship in the study area.Although some stations returned a polarization direction of NNW-SSE.a dominant polarization direction of NW-SE was obtained for the fast shear wave at most seismic stations in the study area.The polarization directions of the fast shear wave were highly consistent throughout the study-area.This orientation was in accordance with the direction of the regional principal compressive stress and parallel to the trend of the Xianshuihe and Daliangshan faults.The distribution of crustal anisotropy in this area was affected by the regional tectonic stress field and the fault structures.The mean delay time between fast and slow shear waves was 3.83 ms/km.slightly greater than the values obtained in other regions of Sichuan.This indicates that the crustal media in our study area had a high anisotropic strength and also reveals the influence of tectonic complexity resulting from the intersection of multiple faults on the strength of seismic anisotropy.展开更多
Shear-wave velocity is a key parameter for calibrating monitoring time-lapse 4D seismic data during CO2-EOR （Enhanced Oil Recovery） and CO2 sequestration. However, actual S-wave velocity data are lacking, especially...Shear-wave velocity is a key parameter for calibrating monitoring time-lapse 4D seismic data during CO2-EOR （Enhanced Oil Recovery） and CO2 sequestration. However, actual S-wave velocity data are lacking, especially in 4D data for CO2 sequestration because wells are closed after the CO2 injection and seismic monitoring is continued but no well log data are acquired. When CO2 is injected into a reservoir, the pressure and saturation of the reservoirs change as well as the elastic parameters of the reservoir rocks. We propose a method to predict the S-wave velocity in reservoirs at different pressures and porosities based on the Hertz-Mindlin and Gassmann equations. Because the coordination number is unknown in the Hertz Mindlin equation, we propose a new method to predict it. Thus, we use data at different CO2 injection stages in the Gao89 well block, Shengli Oilfield. First, the sand and mud beds are separated based on the structural characteristics of the thin sand beds and then the S-wave velocity as a function of reservoir pressure and porosity is calculated. Finally, synthetic seismic seismograms are generated based on the predicted P- and S-wave velocities at different stages of CO2 injection.展开更多
The correlations between shear wave velocity(SWV)calculated from virtual touch tissue imaging quantification(VTIQ)technique and histological prognostic factors of invasive ductal carcinoma was investigated.A total of ...The correlations between shear wave velocity(SWV)calculated from virtual touch tissue imaging quantification(VTIQ)technique and histological prognostic factors of invasive ductal carcinoma was investigated.A total of 76 breast tumors histologically confirmed as invasive ductal carcinomas were included in this study.SWV values were measured by VTIQ for each lesion preoperatively or prior to breast biopsy.The maximum values were recorded for statistical analysis.Medical records were reviewed to determine tumor size,histological grade,lymph node status and immunohistochemical results.Tumor subtypes were categorized as luminal A,luminal B,human epidermal growth factor receptor 2(HER2)positive and triple negative.The correlations between SWV and histological prognostic factors were analyzed.It was found that tumor size showed positive association with SWV(r=0.465,P<0.001).Larger tumors had significantly higher SWV than smaller ones(P=0.001).Histological grade 1 tumors had significantly lower SWV values than those with higher histological grade(P=0.015).The Ki67 expression,tumor subtypes and lymph node status showed no statistically significant correlations with SWV,although triple negative tumors and lymph node-positive tumors showed higher SWV values.It was concluded that tumor size was significantly associated with SWV.Higher histological grade was associated with increased SWV.There was no statistically significant correlations between SWV and other histological prognostic factors.展开更多
We assembled approximately 328 seismic records. The data set was from 4 digitally recording long-period and broadband stations of CDSN. We carried out the inversion based on the partitioned waveform inversion (PWI). I...We assembled approximately 328 seismic records. The data set was from 4 digitally recording long-period and broadband stations of CDSN. We carried out the inversion based on the partitioned waveform inversion (PWI). It partitions the large-scale optimization problem into a number of independent small-scale problems. We adopted surface waveform inversion with an equal block (2((2() discretization in order to acquire the images of shear velocity structure at different depths (from surface to 430 km) in the crust and upper-mantle. The resolution of all these anomalies has been established with (check-board( resolution tests. These results show significant difference in velocity, lithosphere and asthenosphere structure between South China Sea and its adjacent regions.展开更多
AIM:To investigate whether a noninvasive measurement of tissue strain has a potential usefulness for management of nonalcoholic steatohepatitis(NASH).METHODS:In total 26 patients,23 NASHs and 3 normal controls were en...AIM:To investigate whether a noninvasive measurement of tissue strain has a potential usefulness for management of nonalcoholic steatohepatitis(NASH).METHODS:In total 26 patients,23 NASHs and 3 normal controls were enrolled in this study.NASH was staged based on Brunt criterion.At a region of interest(ROI),a shear wave was evoked by implementing an acoustic radiation force impulse(ARFI),and the propagation velocity was quantif ied.RESULTS:Shear wave velocity(SWV) could be reproducibly quantified at all ROIs in all subjects except for 4 NASH cases,in which a reliable SWV value was not calculated at several ROIs.An average SWV of 1.34 ± 0.26 m/s in fibrous stage 0-1 was significantly slower than 2.20 ± 0.74 m/s and 2.90 ± 1.01 m/s in stages 3 and 4,respectively,but was not significantly different from 1.79 ± 0.78 m/s in stage 2.When a cutoff value was set at 1.47 m/s,receiver operating characteristic analysis showed significance to dissociate stages 3 and 4 from stage 0-1(P=0.0092) with sensitivity,specificity and area under curve of 100%,75% and 94.2%,respectively.In addition,the correlation between SWV and hyaluronic acid was significant(P<0.0001),while a tendency toward negative correlation was observed with serum albumin(P=0.053).CONCLUSION:The clinical implementation of ARFI provides noninvasive repeated evaluations of liver stiffness at an arbitrary position,which has the potential to shed new light on NASH management.展开更多
The great Wenchuan earthquake （Ms= 8.0） in 2008 caused severe damage in the western part of the Chengdu Plain. Soil liquefaction was one of the major causes of damage in the plain areas, and proper evaluation of liq...The great Wenchuan earthquake （Ms= 8.0） in 2008 caused severe damage in the western part of the Chengdu Plain. Soil liquefaction was one of the major causes of damage in the plain areas, and proper evaluation of liquefaction potential is important in the definition of the seismic hazard facing a given region and post-earthquake reconstruction. In this paper, a simplified procedure is proposed for liquefaction assessment of sandy deposits using shear wave velocity （V）, and soil liquefaction from the Banqiao School site was preliminarily investigated after the earthquake. Boreholes were made at the site and shear wave velocities were measured both by SASW and down-hole methods. Based on the in-situ soil information and V profiles, the liquefaction potential of this site was evaluated. The results are reasonably consistent with the actual field behavior observed after the earthquake, indicating that the proposed procedure is effective. The possible effects of gravel and fines contents on liquefaction of sandy soils were also briefly discussed.展开更多
AIM To determine the diagnostic accuracy of two-dimensional shear wave elastography(2D-SWE) for the noninvasive assessment of liver fibrosis in patients with autoimmune liver diseases(AILD) using liver biopsy as the r...AIM To determine the diagnostic accuracy of two-dimensional shear wave elastography(2D-SWE) for the noninvasive assessment of liver fibrosis in patients with autoimmune liver diseases(AILD) using liver biopsy as the reference standard.METHODS Patients with AILD who underwent liver biopsy and 2D-SWE were consecutively enrolled. Receiver operating characteristic(ROC) curves were constructed to assess the overall accuracy and to identify optimal cut-off values.RESULTS The characteristics of the diagnostic performance were determined for 114 patients with AILD. The areas under the ROC curves for significant fibrosis, severe fibrosis, and cirrhosis were 0.85, 0.85, and 0.86, respectively, and the optimal cut-off values associated with significant fibrosis(≥ F2), severe fibrosis(≥ F3), and cirrhosis(F4) were 9.7 k Pa, 13.2 k Pa and 16.3 k Pa, respectively. 2D-SWE showed sensitivity values of 81.7% for significant fibrosis, 83.0% for severe fibrosis,and 87.0% for cirrhosis, and the respective specificity values were 81.3%, 74.6%, and 80.2%. The overall concordance rate of the liver stiffness measurements obtained using 2D-SWE vs fibrosis stages was 53.5%.CONCLUSION2D-SWE showed promising diagnostic performance for assessing liver fibrosis stages and exhibited high cut-off values in patients with AILD. Low overall concordance rate was observed in the liver stiffness measurements obtained using 2D-SWE vs fibrosis stages.展开更多
The evaluation and design of stone column improvement ground for liquefaction mitigation is a challenging issue for the state of practice. In this paper, a shear wave velocity-based approach is proposed based on the w...The evaluation and design of stone column improvement ground for liquefaction mitigation is a challenging issue for the state of practice. In this paper, a shear wave velocity-based approach is proposed based on the well-defined correlations of liquefaction resistance （CRR）-shear wave velocity （V）-void ratio （e） of sandy soils, and the values of parameters in this approach are recommended for preliminary design purpose when site specific values are not available. The detailed procedures of pre- and post-improvement liquefaction evaluations and stone column design are given. According to this approach, the required level of ground improvement will be met once the target V of soil is raised high enough （i.e., no less than the critical velocity） to resist the given earthquake loading according to the CRR-V relationship, and then this requirement is transferred to the control of target void ratio （i.e., the critical e） according to the V-e relationship. As this approach relies on the densification of the surrounding soil instead of the whole improved ground and is conservative by nature, specific considerations of the densification mechanism and effect are given, and the effects of drainage and reinforcement of stone columns are also discussed. A case study of a thermal power plant in Indonesia is introduced, where the effectiveness of stone column improved ground was evaluated by the proposed V-based method and compared with the SPT-based evaluation. This improved ground performed well and experienced no liquefaction during subsequent strong earthquakes.展开更多
AIM: To evaluate the correlation of shear wave elastography (SWE) results with liver fibrosis histology and quantitative function reserve. METHODS: Weekly subcutaneous injection of 60% carbon tetrachloride (1.5 mL/kg)...AIM: To evaluate the correlation of shear wave elastography (SWE) results with liver fibrosis histology and quantitative function reserve. METHODS: Weekly subcutaneous injection of 60% carbon tetrachloride (1.5 mL/kg) was given to 12 canines for 24 wk to induce experimental liver fibrosis, with olive oil given to 2 control canines. At 24 wk, liver condition was evaluated using clinical biochemistry assays, SWE imaging, lidocaine metabolite monoethylglycine-xylidide (MEGX) test, and histologic fibrosis grading. Clinical biochemistry assays were performed at the institutional central laboratory for routine liver function evaluation. Liver stiffness was measured in triplicate from three different intercostal spaces and expressed as mean liver stiffness modulus (LSM). Plasma concentrations of lidocaine and its metabolite MEGX were determined using high-performance liquid chromatography repeated in duplicate. Liver biopsy samples were fixed in 10% formaldehyde, and liver fibrosis was graded using the modified histological activity index Knodell score (F0-F4). Correlations among histologic grading, LSM, and MEGX measures were analyzed with the Pearson linear correlation coefficient. RESULTS: At 24 wk liver fibrosis histologic grading was as follows: F0, n = 2 (control); F1, n = 0; F2, n = 3; F3, n = 7; and F4, n = 2. SWE LSM was positively correlated with histologic grading (r = 0.835, P < 0.001). Specifically, the F4 group had a significantly higher elastic modulus than the F3, F2, and F0 groups (P = 0.002, P = 0.003, and P = 0.006, respectively), and the F3 group also had a significantly higher modulus than the control F0 group (P = 0.039). LSM was negatively associated with plasma MEGX concentrations at 30 min (r = -0.642; P = 0.013) and 60 min (r = -0.651; P = 0.012), time to 1/2 of the maximum concentration (r = -0.538; P = 0.047), and the area under the curve (r = -0.636; P = 0.014). Multiple comparisons showed identical differences in these three measures: significantly lower with F4 (P = 0.037) and F3 (P = 0.032) as compared to F0 and significantly lower with F4 as compared to F2 (P = 0.032). CONCLUSION: SWE LSM shows a good correlation with histologic fibrosis grading and pharmacologic quantitative liver function reserve in experimental severe fibrosis and cirrhosis.展开更多
AIM To assess the accuracy of shear wave elastography(SWE)alone and in combination with aminotransferase platelet ratio index(APRI)score in the staging of liver fibrosis.METHODS A multicenter prospective study was con...AIM To assess the accuracy of shear wave elastography(SWE)alone and in combination with aminotransferase platelet ratio index(APRI)score in the staging of liver fibrosis.METHODS A multicenter prospective study was conducted to assess the accuracy of SWE(medians)and APRI to predict biopsy results.The analysis focused on distinguishing the different stages of liver disease,namely,F0 from F1-4,F0-1 from F2-4,F0-2 from F3-4 and F0-3 from F4;F0-F1 from F2-F4 being of primary interest.The area under the receiver operating characteristic(AUROC)curve was computed using logistic regression model.The role of age,gender and steatosis was also assessed.RESULTS SWE alone accurately distinguished F0-1 from F2-4 with a high probability.The AUROC using SWE alone was 0.91 compared to 0.78 for using the APRI score alone.The APRI score,when used in conjunction with SWE,did not make a significant contribution to the AUROC.SWE and steatosis were the only significant predictors that differentiated F0-1 from F2-4 with an AUROC of 0.944.CONCLUSION Our study validates the use of SWE in the diagnosis and staging of liver fibrosis.Furthermore,the probability of a correct diagnosis is significantly enhanced with the addition of steatosis as a prognostic factor.展开更多
BACKGROUND It is important to differentiate benign and malignant focal liver lesions(FLLs)accurately.Despite the wide use and acceptance of shear wave elastography(SWE),its value for assessing the elasticity of FLLs a...BACKGROUND It is important to differentiate benign and malignant focal liver lesions(FLLs)accurately.Despite the wide use and acceptance of shear wave elastography(SWE),its value for assessing the elasticity of FLLs and differentiating benign and malignant FLLs is still investigational.Previous studies of SWE for FLLs used mean elasticity as the parameter to reflect the stiffness of FLLs.Considering the inhomogeneity of tumor stiffness,maximal elasticity(Emax)might be the suitable parameter to reflect the stiffness of FLLs and to differentiate malignant FLLs from benign ones.AIM To explore the value of SWE with Emax in differential diagnosis of solid FLLs.METHODS We included 104 solid FLLs in 95 patients and 50 healthy volunteers.All the subjects were examined using conventional ultrasound(US)and virtual touch tissue quantification(VTQ)imaging.A diagnosis of benign or malignant FLL was made using conventional US.Ten VTQ values were acquired after 10 consecutive measurements for each FLL and each normal liver,and the largest value was recorded as Emax.RESULTS There were 56 cases of malignant FLLs and 48 cases of benign FLLs in this study.Emax of malignant FLLs(3.29±0.88 m/s)was significantly higher than that of benign FLLs(1.30±0.46 m/s,P<0.01)and that of livers in healthy volunteers(1.15±0.17 m/s,P<0.01).The cut-off point of Emax was 1.945,and the area under the curve was 0.978.The sensitivity and specificity of Emax were 92.9%and 91.7%,respectively,higher(but not significantly)than those of conventional US(80.4%for sensitivity and 81.3%for specificity).Combined diagnosis of conventional US and Emax using parallel testing improved the sensitivity to 100%with specificity of 75%.CONCLUSION SWE is a convenient and easy method to obtain accurate stiffness information of solid FLLs.Emax is useful for differential diagnosis of FLLs,especially in combination with conventional US.展开更多
Objective To explore the clinical value of ultrasound shear wave elastography(SWE)and contrast-enhanced ultrasound(CEUS)in transrectal prostate biopsy.Methods A total of 54 patients(average age:67.79±12.01 years)...Objective To explore the clinical value of ultrasound shear wave elastography(SWE)and contrast-enhanced ultrasound(CEUS)in transrectal prostate biopsy.Methods A total of 54 patients(average age:67.79±12.01 years)in the experimental group underwent transrectal prostate biopsy under the guidance of SWE,while 46 patients(average age:69.22±11.54 years)in the control group underwent transrectal prostate biopsy guided by CEUS.Results There were a total of 451 needles,with an average of 8.35±1.67 needles per patient in the experimental group,and a total of 462 needles,with an average of 10.04±1.33 needles per patient in the control group.The difference in puncture times between the two groups was statistically significant(P<0.05).There was no significant difference in the positive detection rate,sensitivity or specificity between the two groups(P>0.05),but there was a significant difference in the diagnostic accuracy between the two groups(P<0.05).The E_(mean)and E_(max)of prostate cancer were significantly higher in the experimental group than in benign prostatic hyperplasia(P<0.05).The receiver operating characteristic curve(ROC)analysis showed that the area under the ROC curve(AUC)of E_(mean)was 0.752(S.E.=0.072,95%CI=0.611-0.894,P=0.007),and the best cutoff value was 47.005 kPa.Conclusion In summary,both SWE-and CEUS-guided transrectal prostate biopsy can help find the focus and guide the puncture,and improve the positive detection rate.展开更多
BACKGROUND The diagnostic specificity of conventional ultrasound for breast non-mass lesions(NMLs)is low at approximately 21%-43%.Shear wave elastography(SWE)can distinguish benign from malignant lesions by evaluating...BACKGROUND The diagnostic specificity of conventional ultrasound for breast non-mass lesions(NMLs)is low at approximately 21%-43%.Shear wave elastography(SWE)can distinguish benign from malignant lesions by evaluating the internal and peripheral stiffness.SWE has good reproducibility and high diagnostic efficacy.However,there are very few independent studies on the diagnostic value of SWE in breast NMLs.AIM To determine the value of SWE in the differential diagnosis of breast NMLs.METHODS This study enrolled a total of 118 patients with breast NMLs who underwent SWE examinations in the Beijing Shijitan Hospital Affiliated to Capital Medical University and The Second Hospital of Shandong University from January 2019 to January 2020.The internal elastic parameters of the lesions were recorded,including maximum(Emax),mean(Emean)and minimum elastic values and the standard deviation.The following peripheral parameters were noted:Presence of a“stiff rim”sign;Emax,and Emean elasticity values within 1 mm,1.5 mm,2 mm,2.5 mm and 3 mm from the edge of NMLs.The receiver operating characteristic curve of each parameter was drawn,and the areas under the curve were calculated.RESULTS Emax,Emean and elastic values,and the standard deviation of the internal elastic values in malignant NMLs were significantly higher than those in benign NMLs(P<0.05).The percentage with the“stiff rim”sign in malignant NMLs was significantly higher than that in the benign group(P<0.05),and Emax and Emean at the shell of 1 mm,1.5 mm,2 mm,2.5 mm and 3 mm in the malignant group were all higher than those in the benign group(P<0.05).Of the surrounding elasticity values,Emax of the shell at 2.5 mm in malignant NMLs had maximum areas under the curve of 0.900,and the corresponding sensitivity and specificity were 94.57%and 85.86%,respectively.CONCLUSION The“stiff rim”sign and multiple quantitative elastic values within and around the lesion had good diagnostic performance in the differential diagnosis of breast NMLs.Emax in peripheral tissue had better diagnostic efficiency than other parameters.展开更多
文摘BACKGROUND Shear wave elastography(SWE)is a non-invasive ultrasound-based technique used to assess tissue stiffness,which reflects underlying pathological changes.While SWE has been widely applied for liver fibrosis evaluation,its application to other abdominal organs,such as the spleen and pancreas,is gaining interest.However,normal stiffness values and inter-system agreement remain poorly defined.AIM To assess the feasibility and agreement of liver,spleen,and pancreas stiffness using three SWE methods.METHODS This single-center observational study enrolled 50 healthy adult volunteers.Liver,spleen,and pancreas stiffness were assessed using three SWE methods:Point-SWE(p-QElaXto)and 2-Dimensional-SWE(2D-QElaXto)with Esaote MyLab 9,and 2D-SWE with SuperSonic Imagine.Feasibility,inter-operator reproducibility,and concordance among systems were evaluated.Stiffness was expressed as median kPa values,and technical reliability was assessed using the interquartile range/median ratio and stability index thresholds.RESULTS Liver and spleen stiffness assessment was feasible in>98%of patients,while pancreas stiffness was measurable in 84%-88%depending on the SWE technique.Mean liver stiffness ranged between 3.9-4.7 kPa across techniques,spleen stiffness ranged from 19.4-23.0 kPa,and pancreas stiffness from 5.2-7.6 kPa.Inter-operator agreement was excellent for liver(intraclass correlation coefficient>0.90)and good to moderate for spleen and pancreas(intraclass correlation coefficient from 0.43 to 0.90).Bland-Altman analysis confirmed good correlation but also systematic differences among devices,especially in pancreas measurements.CONCLUSION This is the first study to establish normal liver,spleen,and pancreas stiffness using MyLab 9 SWE integrated methods as compared to SuperSonic Imagine,with acceptable inter-technique agreement.Liver and spleen values matched existing guidelines;pancreas SWE showed more variability and reduced reproducibility.
基金supported by Scientific Research and Technology Development Project of CNPC(2024ZG38,2024ZG42)the CNPC Innovation Fund(2022DQ02-0307).
文摘Fractures play a crucial role in various fields such as hydrocarbon exploration,groundwater resources management,and earthquake research.The determination of fracture location and the estimation of parameters such as fracture length and dip angle are the focus of geophysical work.In borehole observation system,the short distance between fractures and detectors leads to weak attenuation of elastic wave energy,and high-frequency source makes it easier to identify small-scale fractures.Compared to traditional monopole logging methods,dipole logging method has advantage of exciting pure shear waves sensitive to fractures,so its application is becoming increasingly widespread.However,since the reflected shear waves and scattered shear waves of fractures correspond to different fracture properties,how to distinguish and analyze these two kinds of waves is crucial for accurately characterizing the fracture parameters.To address this issue,numerical simulation of wave responses by a single fracture near a borehole in rock formation is performed,and the generation mechanism and characteristics of shear waves scattered by fractures are investigated.It is found that when the dip angle of the fracture surpasses a critical threshold,the S-wave will propagate to both endpoints of the fracture and generate scattered S-waves,resulting in two distinct scattered wave packets on the received waveform.When the polarization direction of the acoustic source is parallel to the strike of the fracture,the scattered SH-waves always have larger amplitude than the scattered SV-waves regardless of changing the fracture dip angle.Unlike SV-waves,the SH-waves scattered by the fracture do not have any mode conversion.Additionally,propagation of S-waves to a short length fracture can induce dipole mode vibration of the fracture within a wide frequency range.The phenomena of shear waves reflected and scattered by the fracture are further illustrated and verified by two field examples,thus showing the potential of scattered waves for fracture evaluation and characterization with borehole observation system.
基金Supported by the Natural Science Foundation of Shanghai,No.22ZR1458200Medical Ph.D Innovative Talent Base Project of Changning District,No.RCJD2021B09+1 种基金Key Specialty of Changning District,No.20231004Shanghai Changning Maternity and Infant Health Hospital Start-Up Project,No.2020Y-14.
文摘BACKGROUND Thyroid dysfunction during pregnancy is an important disease affecting the health of mothers and children.Two-dimensional(2D)shear wave elastography(SWE)is the newest ultrasonic elastography technology and its value in differentiating benign and malignant thyroid nodules has been widely recognized.However,the value of 2D SWE in evaluating and predicting thyroid function is unclear.AIM To explore prospectively the value of 2D SWE quantitative analysis for the evaluation of thyroid function in the first trimester.METHODS We included outpatients of reproductive age in the Department of Gynecology in Shanghai Changning Maternity and Infant Health Hospital between March 2023 and March 2024 who had conventional ultrasound examination and 2D SWE of the thyroid.They also underwent transvaginal ultrasound examination to confirm early intrauterine pregnancy and serum thyroid stimulating hormone(TSH)level was measured.The patients were divided into pregnant with normal TSH,pregnant with abnormal TSH,and nonpregnant with normal TSH.Conventional ultrasound and 2D SWE results were compared among the three groups.RESULTS A total of 108 patients were included in the study;57 in the pregnant with normal TSH group,18 in the pregnant with abnormal TSH group and 33 were in the nonpregnant with normal TSH group.Thyroid size,thyroid echotexture,2D SWE quantitative parameters including mean elasticity in the region of interest and maximal elasticity in the region of interest showed no significant differences among the three groups(P>0.05).CONCLUSION Conventional ultrasound and 2D SWE features could not reflect the level of serum TSH.
文摘Endoscopic ultrasound-guided shear wave elastography(EUS-SWE)represents a significant advancement in non-invasive tissue characterization,enabling objective assessment of quantitative tissue stiffness in real-time with potential clinical relevance across a variety of gastrointestinal disorders.Recent developments in EUS-SWE have expanded its application beyond hepatic fibrosis to include pancreatic diseases and the evaluation of solid tumors.EUS-SWE has demonstrated diagnostic accuracy comparable to vibration-controlled transient elastography in assessing fibrosis stages,positioning it as a potential alternative to liver biopsy.Moreover,EUS-SWE has shown promise in evaluating pancreatic tissue stiffness,aiding in the diagnosis and monitoring of chronic pancreatitis and pancreatic cancer.This technique offers a distinct advantage by allowing tissue stiffness measurements during the same procedure,thereby reducing the need for additional imaging studies and biopsies.Despite its clinical potential,challenges remain,including the need for standardized protocols,optimal cutoff values,and validation across diverse patient populations.This minireview provides a comprehensive analysis of the current literature on EUS-SWE,examining its diagnostic performance,reproducibility,and limitations.Furthermore,we discuss the future directions of EUS-SWE,including its integration into routine clinical practice and its evolving role in precision medicine,emphasizing the necessity of large-scale studies to solidify its clinical utility and establish standardized guidelines for its use.
基金Supported by Guangdong Medical Science and Technology Research Fund Project,No.A2024475.
文摘This study explores the significance of using two-dimensional shear wave elastography(2D-SWE)to assess liver stiffness(LS)and spleen area(SPA)for predicting post-hepatectomy liver failure(PHLF).By providing a non-invasive method to measure LS,which correlates with the degree of liver fibrosis,and SPA,an indicator of portal hypertension,2D-SWE offers a comprehensive evaluation of a patient’s hepatic status.These advancements are particularly crucial in hepatic surgery,where accurate preoperative assessments are essential for optimizing surgical outcomes and minimizing complications.This letter highlights the prac-tical implications of integrating 2D-SWE into clinical practice,emphasizing its potential to improve patient safety and surgical precision by enhancing the ability to predict PHLF and tailor surgical approaches accordingly.
基金supported by Research Project in Earthquake Science(Nos.201308018 and No.201108002) National Natural Science Foundation of China(No.40904012)
文摘Using seismic data of the aftershocks sequence of the April 20, 2013 Lushan earthquake recorded by seismic temporary and permanent stations in the source region, with the visual inspection of particle motion diagrams, this paper preliminarily contains the polarization directions of fast shear wave and the time-delays of split shear waves at every station, and analyzes the crustal anisotropic characteristics in the source region. In the study area, the polarization direc- tions at stations BAX, TQU, L 132, L 133, L 134, and L 135 are northeast, which is consistent with the strike of Dachuan- Shuangshi fault. There are two polarization directions at MDS and L131, which are northeast and southeast. The scatter of polarization directions suggests the complex stress field around these two stations where two faults intersect. For the normalized time-delays at every station, the range is 1.02-8.64 ms/km. The largest time-delay is from L134 which is closest to the mainshock, and the smallest one is from L133. The variations in time-delays show the decreasing at stations BAX, L134, and L135 because of the stress-relaxation after earthquake.
基金This work is jointly supported by the National Natural Science Foundation of China(No.41904057)the National Key Research and Development Program of China(No.2018YFC1503402).
文摘The Shimian area of Sichuan sits at the junction of the Bayan Har block.Sichuan-Yunnan rhombic block,and Yangtze block,where several faults intersect.This region features intense tectonic activity and frequent earthquakes.In this study,we used local seismic waveform data recorded using dense arrays deployed in the Shimian area to obtain the shear wave splitting parameters at 55 seismic stations and thereby determine the crustal anisotropic characteristics of the region.We then analyzed the crustal stress pattern and tectonic setting and explored their relationship in the study area.Although some stations returned a polarization direction of NNW-SSE.a dominant polarization direction of NW-SE was obtained for the fast shear wave at most seismic stations in the study area.The polarization directions of the fast shear wave were highly consistent throughout the study-area.This orientation was in accordance with the direction of the regional principal compressive stress and parallel to the trend of the Xianshuihe and Daliangshan faults.The distribution of crustal anisotropy in this area was affected by the regional tectonic stress field and the fault structures.The mean delay time between fast and slow shear waves was 3.83 ms/km.slightly greater than the values obtained in other regions of Sichuan.This indicates that the crustal media in our study area had a high anisotropic strength and also reveals the influence of tectonic complexity resulting from the intersection of multiple faults on the strength of seismic anisotropy.
基金supported by the National High Techology Research and Development Program(No.2012AA050103)
文摘Shear-wave velocity is a key parameter for calibrating monitoring time-lapse 4D seismic data during CO2-EOR （Enhanced Oil Recovery） and CO2 sequestration. However, actual S-wave velocity data are lacking, especially in 4D data for CO2 sequestration because wells are closed after the CO2 injection and seismic monitoring is continued but no well log data are acquired. When CO2 is injected into a reservoir, the pressure and saturation of the reservoirs change as well as the elastic parameters of the reservoir rocks. We propose a method to predict the S-wave velocity in reservoirs at different pressures and porosities based on the Hertz-Mindlin and Gassmann equations. Because the coordination number is unknown in the Hertz Mindlin equation, we propose a new method to predict it. Thus, we use data at different CO2 injection stages in the Gao89 well block, Shengli Oilfield. First, the sand and mud beds are separated based on the structural characteristics of the thin sand beds and then the S-wave velocity as a function of reservoir pressure and porosity is calculated. Finally, synthetic seismic seismograms are generated based on the predicted P- and S-wave velocities at different stages of CO2 injection.
基金grants from the Fundamental Research Funds for the Central Universities(No.2172015YGYL019)the Fundamental Research Funds for the Central Universities(No.2015LC021)+1 种基金National Natural Science Foundation of China(No.81000616)Hubei Key Laboratory of Molecular Imaging Research Funds(No.02.03.2015-149).
文摘The correlations between shear wave velocity(SWV)calculated from virtual touch tissue imaging quantification(VTIQ)technique and histological prognostic factors of invasive ductal carcinoma was investigated.A total of 76 breast tumors histologically confirmed as invasive ductal carcinomas were included in this study.SWV values were measured by VTIQ for each lesion preoperatively or prior to breast biopsy.The maximum values were recorded for statistical analysis.Medical records were reviewed to determine tumor size,histological grade,lymph node status and immunohistochemical results.Tumor subtypes were categorized as luminal A,luminal B,human epidermal growth factor receptor 2(HER2)positive and triple negative.The correlations between SWV and histological prognostic factors were analyzed.It was found that tumor size showed positive association with SWV(r=0.465,P<0.001).Larger tumors had significantly higher SWV than smaller ones(P=0.001).Histological grade 1 tumors had significantly lower SWV values than those with higher histological grade(P=0.015).The Ki67 expression,tumor subtypes and lymph node status showed no statistically significant correlations with SWV,although triple negative tumors and lymph node-positive tumors showed higher SWV values.It was concluded that tumor size was significantly associated with SWV.Higher histological grade was associated with increased SWV.There was no statistically significant correlations between SWV and other histological prognostic factors.
基金State Natural Scientific Foundation (49734150) and National High Performance Computation Foundation.
文摘We assembled approximately 328 seismic records. The data set was from 4 digitally recording long-period and broadband stations of CDSN. We carried out the inversion based on the partitioned waveform inversion (PWI). It partitions the large-scale optimization problem into a number of independent small-scale problems. We adopted surface waveform inversion with an equal block (2((2() discretization in order to acquire the images of shear velocity structure at different depths (from surface to 430 km) in the crust and upper-mantle. The resolution of all these anomalies has been established with (check-board( resolution tests. These results show significant difference in velocity, lithosphere and asthenosphere structure between South China Sea and its adjacent regions.
文摘AIM:To investigate whether a noninvasive measurement of tissue strain has a potential usefulness for management of nonalcoholic steatohepatitis(NASH).METHODS:In total 26 patients,23 NASHs and 3 normal controls were enrolled in this study.NASH was staged based on Brunt criterion.At a region of interest(ROI),a shear wave was evoked by implementing an acoustic radiation force impulse(ARFI),and the propagation velocity was quantif ied.RESULTS:Shear wave velocity(SWV) could be reproducibly quantified at all ROIs in all subjects except for 4 NASH cases,in which a reliable SWV value was not calculated at several ROIs.An average SWV of 1.34 ± 0.26 m/s in fibrous stage 0-1 was significantly slower than 2.20 ± 0.74 m/s and 2.90 ± 1.01 m/s in stages 3 and 4,respectively,but was not significantly different from 1.79 ± 0.78 m/s in stage 2.When a cutoff value was set at 1.47 m/s,receiver operating characteristic analysis showed significance to dissociate stages 3 and 4 from stage 0-1(P=0.0092) with sensitivity,specificity and area under curve of 100%,75% and 94.2%,respectively.In addition,the correlation between SWV and hyaluronic acid was significant(P<0.0001),while a tendency toward negative correlation was observed with serum albumin(P=0.053).CONCLUSION:The clinical implementation of ARFI provides noninvasive repeated evaluations of liver stiffness at an arbitrary position,which has the potential to shed new light on NASH management.
基金National Basic Research Program of China (973 Project) Under Grant No. 2007CB714203the Foundation for Seismological Researches, China Earthquake Administration Under Grant No. 200808022+1 种基金the China Postdoctoral Science Foundation Under Grant No. 20080430219, No. 20081476the National Natural Science Foundation of China Under Grant No. 50708095
文摘The great Wenchuan earthquake （Ms= 8.0） in 2008 caused severe damage in the western part of the Chengdu Plain. Soil liquefaction was one of the major causes of damage in the plain areas, and proper evaluation of liquefaction potential is important in the definition of the seismic hazard facing a given region and post-earthquake reconstruction. In this paper, a simplified procedure is proposed for liquefaction assessment of sandy deposits using shear wave velocity （V）, and soil liquefaction from the Banqiao School site was preliminarily investigated after the earthquake. Boreholes were made at the site and shear wave velocities were measured both by SASW and down-hole methods. Based on the in-situ soil information and V profiles, the liquefaction potential of this site was evaluated. The results are reasonably consistent with the actual field behavior observed after the earthquake, indicating that the proposed procedure is effective. The possible effects of gravel and fines contents on liquefaction of sandy soils were also briefly discussed.
文摘AIM To determine the diagnostic accuracy of two-dimensional shear wave elastography(2D-SWE) for the noninvasive assessment of liver fibrosis in patients with autoimmune liver diseases(AILD) using liver biopsy as the reference standard.METHODS Patients with AILD who underwent liver biopsy and 2D-SWE were consecutively enrolled. Receiver operating characteristic(ROC) curves were constructed to assess the overall accuracy and to identify optimal cut-off values.RESULTS The characteristics of the diagnostic performance were determined for 114 patients with AILD. The areas under the ROC curves for significant fibrosis, severe fibrosis, and cirrhosis were 0.85, 0.85, and 0.86, respectively, and the optimal cut-off values associated with significant fibrosis(≥ F2), severe fibrosis(≥ F3), and cirrhosis(F4) were 9.7 k Pa, 13.2 k Pa and 16.3 k Pa, respectively. 2D-SWE showed sensitivity values of 81.7% for significant fibrosis, 83.0% for severe fibrosis,and 87.0% for cirrhosis, and the respective specificity values were 81.3%, 74.6%, and 80.2%. The overall concordance rate of the liver stiffness measurements obtained using 2D-SWE vs fibrosis stages was 53.5%.CONCLUSION2D-SWE showed promising diagnostic performance for assessing liver fibrosis stages and exhibited high cut-off values in patients with AILD. Low overall concordance rate was observed in the liver stiffness measurements obtained using 2D-SWE vs fibrosis stages.
基金National Natural Science Foundation of China under Grant No.51578501 and No.51127005the Foundation for the Author of National Excellent Doctoral Dissertation of P R China under Grant No.201160+3 种基金the Zhejiang Provincial Natural Science Foundation of China under Grant No.LR15E080001the National Basic Research Program of China(973 Project)under Grant No.2014CB047005the Fundamental Research Funds for the Central Universities under Grant No.2014FZA4016Zhejiang University K.P.Chao’s High Technology Development Foundation(2014)
文摘The evaluation and design of stone column improvement ground for liquefaction mitigation is a challenging issue for the state of practice. In this paper, a shear wave velocity-based approach is proposed based on the well-defined correlations of liquefaction resistance （CRR）-shear wave velocity （V）-void ratio （e） of sandy soils, and the values of parameters in this approach are recommended for preliminary design purpose when site specific values are not available. The detailed procedures of pre- and post-improvement liquefaction evaluations and stone column design are given. According to this approach, the required level of ground improvement will be met once the target V of soil is raised high enough （i.e., no less than the critical velocity） to resist the given earthquake loading according to the CRR-V relationship, and then this requirement is transferred to the control of target void ratio （i.e., the critical e） according to the V-e relationship. As this approach relies on the densification of the surrounding soil instead of the whole improved ground and is conservative by nature, specific considerations of the densification mechanism and effect are given, and the effects of drainage and reinforcement of stone columns are also discussed. A case study of a thermal power plant in Indonesia is introduced, where the effectiveness of stone column improved ground was evaluated by the proposed V-based method and compared with the SPT-based evaluation. This improved ground performed well and experienced no liquefaction during subsequent strong earthquakes.
基金Supported by National Natural Science Foundation of ChinaNo.81401425
文摘AIM: To evaluate the correlation of shear wave elastography (SWE) results with liver fibrosis histology and quantitative function reserve. METHODS: Weekly subcutaneous injection of 60% carbon tetrachloride (1.5 mL/kg) was given to 12 canines for 24 wk to induce experimental liver fibrosis, with olive oil given to 2 control canines. At 24 wk, liver condition was evaluated using clinical biochemistry assays, SWE imaging, lidocaine metabolite monoethylglycine-xylidide (MEGX) test, and histologic fibrosis grading. Clinical biochemistry assays were performed at the institutional central laboratory for routine liver function evaluation. Liver stiffness was measured in triplicate from three different intercostal spaces and expressed as mean liver stiffness modulus (LSM). Plasma concentrations of lidocaine and its metabolite MEGX were determined using high-performance liquid chromatography repeated in duplicate. Liver biopsy samples were fixed in 10% formaldehyde, and liver fibrosis was graded using the modified histological activity index Knodell score (F0-F4). Correlations among histologic grading, LSM, and MEGX measures were analyzed with the Pearson linear correlation coefficient. RESULTS: At 24 wk liver fibrosis histologic grading was as follows: F0, n = 2 (control); F1, n = 0; F2, n = 3; F3, n = 7; and F4, n = 2. SWE LSM was positively correlated with histologic grading (r = 0.835, P < 0.001). Specifically, the F4 group had a significantly higher elastic modulus than the F3, F2, and F0 groups (P = 0.002, P = 0.003, and P = 0.006, respectively), and the F3 group also had a significantly higher modulus than the control F0 group (P = 0.039). LSM was negatively associated with plasma MEGX concentrations at 30 min (r = -0.642; P = 0.013) and 60 min (r = -0.651; P = 0.012), time to 1/2 of the maximum concentration (r = -0.538; P = 0.047), and the area under the curve (r = -0.636; P = 0.014). Multiple comparisons showed identical differences in these three measures: significantly lower with F4 (P = 0.037) and F3 (P = 0.032) as compared to F0 and significantly lower with F4 as compared to F2 (P = 0.032). CONCLUSION: SWE LSM shows a good correlation with histologic fibrosis grading and pharmacologic quantitative liver function reserve in experimental severe fibrosis and cirrhosis.
基金the Aga Khan United States Research funding body and research support team for funding this study
文摘AIM To assess the accuracy of shear wave elastography(SWE)alone and in combination with aminotransferase platelet ratio index(APRI)score in the staging of liver fibrosis.METHODS A multicenter prospective study was conducted to assess the accuracy of SWE(medians)and APRI to predict biopsy results.The analysis focused on distinguishing the different stages of liver disease,namely,F0 from F1-4,F0-1 from F2-4,F0-2 from F3-4 and F0-3 from F4;F0-F1 from F2-F4 being of primary interest.The area under the receiver operating characteristic(AUROC)curve was computed using logistic regression model.The role of age,gender and steatosis was also assessed.RESULTS SWE alone accurately distinguished F0-1 from F2-4 with a high probability.The AUROC using SWE alone was 0.91 compared to 0.78 for using the APRI score alone.The APRI score,when used in conjunction with SWE,did not make a significant contribution to the AUROC.SWE and steatosis were the only significant predictors that differentiated F0-1 from F2-4 with an AUROC of 0.944.CONCLUSION Our study validates the use of SWE in the diagnosis and staging of liver fibrosis.Furthermore,the probability of a correct diagnosis is significantly enhanced with the addition of steatosis as a prognostic factor.
基金Natural Science Foundation of Shanghai of China,No.19ZR1441500.
文摘BACKGROUND It is important to differentiate benign and malignant focal liver lesions(FLLs)accurately.Despite the wide use and acceptance of shear wave elastography(SWE),its value for assessing the elasticity of FLLs and differentiating benign and malignant FLLs is still investigational.Previous studies of SWE for FLLs used mean elasticity as the parameter to reflect the stiffness of FLLs.Considering the inhomogeneity of tumor stiffness,maximal elasticity(Emax)might be the suitable parameter to reflect the stiffness of FLLs and to differentiate malignant FLLs from benign ones.AIM To explore the value of SWE with Emax in differential diagnosis of solid FLLs.METHODS We included 104 solid FLLs in 95 patients and 50 healthy volunteers.All the subjects were examined using conventional ultrasound(US)and virtual touch tissue quantification(VTQ)imaging.A diagnosis of benign or malignant FLL was made using conventional US.Ten VTQ values were acquired after 10 consecutive measurements for each FLL and each normal liver,and the largest value was recorded as Emax.RESULTS There were 56 cases of malignant FLLs and 48 cases of benign FLLs in this study.Emax of malignant FLLs(3.29±0.88 m/s)was significantly higher than that of benign FLLs(1.30±0.46 m/s,P<0.01)and that of livers in healthy volunteers(1.15±0.17 m/s,P<0.01).The cut-off point of Emax was 1.945,and the area under the curve was 0.978.The sensitivity and specificity of Emax were 92.9%and 91.7%,respectively,higher(but not significantly)than those of conventional US(80.4%for sensitivity and 81.3%for specificity).Combined diagnosis of conventional US and Emax using parallel testing improved the sensitivity to 100%with specificity of 75%.CONCLUSION SWE is a convenient and easy method to obtain accurate stiffness information of solid FLLs.Emax is useful for differential diagnosis of FLLs,especially in combination with conventional US.
基金The study was funded by Inner Mongolia Natural Science Foundation(2020MS08047).
文摘Objective To explore the clinical value of ultrasound shear wave elastography(SWE)and contrast-enhanced ultrasound(CEUS)in transrectal prostate biopsy.Methods A total of 54 patients(average age:67.79±12.01 years)in the experimental group underwent transrectal prostate biopsy under the guidance of SWE,while 46 patients(average age:69.22±11.54 years)in the control group underwent transrectal prostate biopsy guided by CEUS.Results There were a total of 451 needles,with an average of 8.35±1.67 needles per patient in the experimental group,and a total of 462 needles,with an average of 10.04±1.33 needles per patient in the control group.The difference in puncture times between the two groups was statistically significant(P<0.05).There was no significant difference in the positive detection rate,sensitivity or specificity between the two groups(P>0.05),but there was a significant difference in the diagnostic accuracy between the two groups(P<0.05).The E_(mean)and E_(max)of prostate cancer were significantly higher in the experimental group than in benign prostatic hyperplasia(P<0.05).The receiver operating characteristic curve(ROC)analysis showed that the area under the ROC curve(AUC)of E_(mean)was 0.752(S.E.=0.072,95%CI=0.611-0.894,P=0.007),and the best cutoff value was 47.005 kPa.Conclusion In summary,both SWE-and CEUS-guided transrectal prostate biopsy can help find the focus and guide the puncture,and improve the positive detection rate.
文摘BACKGROUND The diagnostic specificity of conventional ultrasound for breast non-mass lesions(NMLs)is low at approximately 21%-43%.Shear wave elastography(SWE)can distinguish benign from malignant lesions by evaluating the internal and peripheral stiffness.SWE has good reproducibility and high diagnostic efficacy.However,there are very few independent studies on the diagnostic value of SWE in breast NMLs.AIM To determine the value of SWE in the differential diagnosis of breast NMLs.METHODS This study enrolled a total of 118 patients with breast NMLs who underwent SWE examinations in the Beijing Shijitan Hospital Affiliated to Capital Medical University and The Second Hospital of Shandong University from January 2019 to January 2020.The internal elastic parameters of the lesions were recorded,including maximum(Emax),mean(Emean)and minimum elastic values and the standard deviation.The following peripheral parameters were noted:Presence of a“stiff rim”sign;Emax,and Emean elasticity values within 1 mm,1.5 mm,2 mm,2.5 mm and 3 mm from the edge of NMLs.The receiver operating characteristic curve of each parameter was drawn,and the areas under the curve were calculated.RESULTS Emax,Emean and elastic values,and the standard deviation of the internal elastic values in malignant NMLs were significantly higher than those in benign NMLs(P<0.05).The percentage with the“stiff rim”sign in malignant NMLs was significantly higher than that in the benign group(P<0.05),and Emax and Emean at the shell of 1 mm,1.5 mm,2 mm,2.5 mm and 3 mm in the malignant group were all higher than those in the benign group(P<0.05).Of the surrounding elasticity values,Emax of the shell at 2.5 mm in malignant NMLs had maximum areas under the curve of 0.900,and the corresponding sensitivity and specificity were 94.57%and 85.86%,respectively.CONCLUSION The“stiff rim”sign and multiple quantitative elastic values within and around the lesion had good diagnostic performance in the differential diagnosis of breast NMLs.Emax in peripheral tissue had better diagnostic efficiency than other parameters.
