Summary: To study reliability and reliable indices of quantitative assessment of right ventricular systolic function by time-intensity curve (TIC) with right ventricular contrast, 5 % sonicated human albumin was injec...Summary: To study reliability and reliable indices of quantitative assessment of right ventricular systolic function by time-intensity curve (TIC) with right ventricular contrast, 5 % sonicated human albumin was injected intravenously at a does of 0.08 ml/kg into 10 dogs at baseline status and cardiac insufficiency. Apical four-chamber view was observed for washin and washout of contrast agent from right ventricle. The parameters of TIC were obtained by curve fitting. The differences of parameters were analyzed in different states of cardiac functions. Among the parameters derived from TIC, the time constant (k) was decreased significantly with decline of cardiac function (P<0.001). But half-time of decent of peak intensity (HT) and mean-transit-time (MTT) of washout were increased significantly (P<0.001). The k was strongly related to cardiac output of right ventricle (CO) and ejection fraction (EF) of left ventricle and fractional shortening (FS) of left ventricle. Right ventricular systolic function could be assessed reliably by the parameters derived from TIC with right ventricular contrast echocardiography. The k, HT and MTT are reliable indices for quantitative assessment of right ventricular systolic function.展开更多
Objective： To present a self-developed experimental system for basic studies of blood perfusion imaging and time-intensity evaluating based on ultrasound contrast agent. Methods ： The experimental system performed t...Objective： To present a self-developed experimental system for basic studies of blood perfusion imaging and time-intensity evaluating based on ultrasound contrast agent. Methods ： The experimental system performed the image reconstruction and time-intensity processing with radio frequency signals. The system was comprised of ultra-high speed hardware data acquisition interface and low computational cost algorithms. The self-made contrast agent ,blood mimic phantom and capillary phantom model were used to validate the experimental system. Results： The images acquired in blood phantoms with linear-array and curve-array transducers were given. The time-intensity curves corresponding to selected region of interestsequence were demonstrated. It was also shown the time-intensity based decay curves and a decay of ultrasound contrast agent under different ultrasound powers. Conclusion： Several suited from two in vitro phantom models show that the experimental system can be used to f blood perfusion and further clinical studies of microvasculature perfusion.展开更多
BACKGROUND Non-invasive differential diagnosis between hepatocellular carcinoma(HCC)and other liver cancer(i.e.cholangiocarcinoma or metastasis)is highly challenging and definitive diagnosis still relies on histologic...BACKGROUND Non-invasive differential diagnosis between hepatocellular carcinoma(HCC)and other liver cancer(i.e.cholangiocarcinoma or metastasis)is highly challenging and definitive diagnosis still relies on histological exam.The patterns of enhancement and wash-out of liver nodules can be used to stratify the risk of malignancy only in cirrhotic patients and HCC frequently shows atypical features.Dynamic contrast-enhanced ultrasound(DCEUS)with standardized software could help to overcome these obstacles,providing functional and quantitative parameters and potentially improving accuracy in the evaluation of tumor perfusion.AIM To explore clinical evidence regarding the application of DCEUS in the differential diagnosis of liver nodules.METHODS A comprehensive literature search of clinical studies was performed to identify the parameters of DCEUS that could relate to histological diagnosis.In accordance with the study protocol,a qualitative and quantitative analysis of the evidence was planned.RESULTS Rise time was significantly higher in HCC patients with a standardized mean difference(SMD)of 0.83(95%CI:0.48-1.18).Similarly,other statistically significant parameters were mean transit time local with a SMD of 0.73(95%CI:0.20-1.27),peak enhancement with a SMD of 0.37(95%CI:0.03-0.70),area wash-in area under the curve with a SMD of 0.47(95%CI:0.13-0.81),wash-out area under the curve with a SMD of 0.55(95%CI:0.21-0.89)and wash-in and wash-out area under the curve with SMD of 0.51(95%CI:0.17-0.85).SMD resulted not significant in fall time and wash-in rate,but the latter presented a trend towards greater values in HCC compared to intrahepatic cholangiocarcinoma.CONCLUSION DCEUS could improve non-invasive diagnosis of HCC,leading to less liver biopsy and early treatment.This quantitative analysis needs to be applied on larger cohorts to confirm these preliminary results.展开更多
Contrast enhanced ultrasound(CEUS)has been widely implemented in clinical practice because of the enormous quantity of information it provides,along with its low cost,reproducibility,minimal invasiveness,and safety of...Contrast enhanced ultrasound(CEUS)has been widely implemented in clinical practice because of the enormous quantity of information it provides,along with its low cost,reproducibility,minimal invasiveness,and safety of the secondgeneration ultrasound contrast agents.To overcome the limitation of CEUS given by the subjective evaluation of the contrast enhancement behaviour,quantitative analysis of contrast kinetics with generation of time-intensity curves has been introduced in recent years.The quantification of perfusion parameters[named as dynamic-CEUS(D-CEUS)]has several applications in gastrointestinal neoplastic and inflammatory disorders.However,the limited availability of large studies and the heterogeneity of the technologies employed have precluded the standardisation of D-CEUS,which potentially represents a valuable tool for clinical practice in management of gastrointestinal diseases.In this article,we reviewed the evidence exploring the application of D-CEUS in gastrointestinal diseases,with a special focus on liver,pancreas,and inflammatory bowel diseases.展开更多
Examinations with a visualisation of the anatomy and pathology of the gastrointestinal(GI) tract are often necessary for the diagnosis of GI diseases.Traditional radiology played a crucial role for many years.Endoscop...Examinations with a visualisation of the anatomy and pathology of the gastrointestinal(GI) tract are often necessary for the diagnosis of GI diseases.Traditional radiology played a crucial role for many years.Endoscopy,despite some limitations,remains the main technique in the differential diagnosis and treatment of GI diseases.In the last decades,the introduction of,and advances in,non-invasive cross-sectional imaging modalities,including ultrasound(US),computed tomography(CT),positron-emission tomography(PET),and magnetic resonance imaging,as well as improvements in the resolution of imaging data,the acquisition of 3D images,and the introduction of contrast-enhancement,have modified the approach to the examination of the GI tract.Moreover,additional co-registration techniques,such as PET-CT and PET-MRI,allow multimodal data acquisition with better sensitivity and specificity in the study of tissue pathology.US has had a growing role in the development and application of the techniques for diagnosis and management of GI diseases because it is inexpensive,non-invasive,and more comfortable for the patient,and it has sufficient diagnostic accuracy toprovide the clinician with image data of high temporal and spatial resolution.Moreover,Doppler and contrastenhanced ultrasound(CEUS) add important information about blood flow.This article provides a general review of the current literature regarding imaging modalities used for the evaluation of bowel diseases,highlighting the role of US and recent developments in CEUS.展开更多
In the current study, we sought to evaluate the diagnostic efficacies of conventional ultrasound（US）, contrastenhanced US（CEUS）, combined US and CEUS and magnetic resonance imaging（MRI） in detecting focal solid ...In the current study, we sought to evaluate the diagnostic efficacies of conventional ultrasound（US）, contrastenhanced US（CEUS）, combined US and CEUS and magnetic resonance imaging（MRI） in detecting focal solid breast lesions. Totally 117 patients with 120 BI-RADS category 4A-5 breast lesions were evaluated by conventional US and CEUS, and MRI, respectively. SonoVue was used as contrast agent in CEUS and injected as an intravenous bolus; nodule scan was performed 4 minutes after bolus injection. A specific sonographic quantification software was used to obtain color-coded maps of perfusion parameters for the investigated lesion, namely the time-intensity curve.The pattern of contrast enhancement and related indexes regarding the time-intensity curve were used to describe the lesions, comparatively with pathological results. Histopathologic examination revealed 46 benign and 74 malignant lesions. Sensitivity, specificity, and accuracy of US in detecting malignant breast lesions were 90.14%, 95.92%, and 92.52%, respectively. Meanwhile, CE-MRI showed sensitivity, specificity, and accuracy of 88.73%, 95.92%, and91.67%, respectively. The area under the ROC curve for combined US and CEUS in discriminating benign from malignant breast lesions was 0.936, while that of MRI was 0.923, with no significant difference between them, as well as among groups. The time-intensity curve of malignant hypervascular fibroadenoma and papillary lesions mostly showed a fast-in/fast-out pattern, with no good correlation between them（kappa 〈0.20）. In conclusion, the combined use of conventional US and CEUS displays good agreement with MRI in differentiating benign from malignant breast lesions.展开更多
AIM:To study the role of time-intensity curve(TIC) analysis parameters in a complex system of neural networks designed to classify liver tumors.METHODS:We prospectively included 112 patients with hepatocellular carcin...AIM:To study the role of time-intensity curve(TIC) analysis parameters in a complex system of neural networks designed to classify liver tumors.METHODS:We prospectively included 112 patients with hepatocellular carcinoma(HCC)(n = 41),hypervascular(n = 20) and hypovascular(n = 12) liver metastases,hepatic hemangiomas(n = 16) or focal fatty changes(n = 23) who underwent contrast-enhanced ultrasonography in the Research Center of Gastroenterology and Hepatology,Craiova,Romania.We recorded full length movies of all contrast uptake phases and post-processed them offline by selecting two areas of interest(one for the tumor and one for the healthy surrounding parenchyma) and consecutive TIC analysis.The difference in maximum intensities,the time to reaching them and the aspect of the late/portal phase,as quantified by the neural network and a ratio between median intensities of the central and peripheral areas were analyzed by a feed forward back propagation multi-layer neural network which was trained to classify data into five distinct classes,corresponding to each type of liver lesion.RESULTS:The neural network had 94.45% training accuracy(95% CI:89.31%-97.21%) and 87.12% testing accuracy(95% CI:86.83%-93.17%).The automatic classification process registered 93.2% sensitivity,89.7% specificity,94.42% positive predictive value and 87.57% negative predictive value.The artificial neural networks(ANN) incorrectly classified as hemangyomas three HCC cases and two hypervascular metastases,while in turn misclassifying four liver hemangyomas as HCC(one case) and hypervascular metastases(three cases).Comparatively,human interpretation of TICs showed 94.1% sensitivity,90.7% specificity,95.11% positive predictive value and 88.89% negative predictive value.The accuracy and specificity of the ANN diagnosis system was similar to that of human interpretation of the TICs(P = 0.225 and P = 0.451,respectively).Hepatocellular carcinoma cases showed contrast uptake during the arterial phase followed by wash-out in the portal and first seconds of the late phases.For the hypovascular metastases did not show significant contrast uptake during the arterial phase,which resulted in negative differences between the maximum intensities.We registered wash-out in the late phase for most of the hypervascular metastases.Liver hemangiomas had contrast uptake in the arterial phase without agent wash-out in the portallate phases.The focal fatty changes did not show any differences from surrounding liver parenchyma,resulting in similar TIC patterns and extracted parameters.CONCLUSION:Neural network analysis of contrastenhanced ultrasonography-obtained TICs seems a promising field of development for future techniques,providing fast and reliable diagnostic aid for the clinician.展开更多
Background Assessment of perfusion in the early period of acute renal failure （ARF） is important,and can not be made by conventional ultrasound.The aim of this study was to prospectively test in a rabbit ARF model w...Background Assessment of perfusion in the early period of acute renal failure （ARF） is important,and can not be made by conventional ultrasound.The aim of this study was to prospectively test in a rabbit ARF model whether real-time contrast-enhanced ultrasound （CEUS） can quantitatively evaluate the hemodynamic changes of renal cortex in the early period.Methods The model of ARF was induced in 30 healthy New Zealand white rabbits （2.5-3.0 kg）,by intramuscular injection of 50% glycerin solution （12 ml/kg）.CEUS were performed on right kidneys before,6 and 24 hours after glycerin injection.CEUS quantitative indexes were measured in renal cortex using QLAB software.Comparisons between different stages were performed using paired t test.The sensitivity of CEUS in diagnosing ARF was compared with blood serum urea nitrogen （BUN）,serum creatinine （SCr） level and color Doppler flow imaging （CDFI）.Results Among quantitative indexes,time to peak （TTP） and area under curve （AUC） increased significantly from （5.86±2.57） seconds and （124.4±46.7） dB.s before glycerin injection to （7.66±2.05） seconds and （288.1±64.9） dB.s 6 hours after injection （P 〈0.05）.Slope rate of ascending curve （A） and descending curve （α） decreased slightly from （3.00±1.22） dB/s and （0.19±0.15） 1/s to （2.80±1.45） dB.s and （0.09±0.02） 1/s （P 〈0.05）.Twenty-four hours later,only AUC increased significantly from （124.4±46.7） dB.s to （466.2±52.2） dB.s （P〈0.05）.Conclusion Quantitative indexes of CEUS might be useful in predicting the hemodynamic changes of renal cortex in the early six hours of ARF model.展开更多
文摘Summary: To study reliability and reliable indices of quantitative assessment of right ventricular systolic function by time-intensity curve (TIC) with right ventricular contrast, 5 % sonicated human albumin was injected intravenously at a does of 0.08 ml/kg into 10 dogs at baseline status and cardiac insufficiency. Apical four-chamber view was observed for washin and washout of contrast agent from right ventricle. The parameters of TIC were obtained by curve fitting. The differences of parameters were analyzed in different states of cardiac functions. Among the parameters derived from TIC, the time constant (k) was decreased significantly with decline of cardiac function (P<0.001). But half-time of decent of peak intensity (HT) and mean-transit-time (MTT) of washout were increased significantly (P<0.001). The k was strongly related to cardiac output of right ventricle (CO) and ejection fraction (EF) of left ventricle and fractional shortening (FS) of left ventricle. Right ventricular systolic function could be assessed reliably by the parameters derived from TIC with right ventricular contrast echocardiography. The k, HT and MTT are reliable indices for quantitative assessment of right ventricular systolic function.
基金Supported by the National Natural Science Foundation of China(30270404)Specialized Research Fund for the Doctoral Program of Higher Education(2003069816)
文摘Objective： To present a self-developed experimental system for basic studies of blood perfusion imaging and time-intensity evaluating based on ultrasound contrast agent. Methods ： The experimental system performed the image reconstruction and time-intensity processing with radio frequency signals. The system was comprised of ultra-high speed hardware data acquisition interface and low computational cost algorithms. The self-made contrast agent ,blood mimic phantom and capillary phantom model were used to validate the experimental system. Results： The images acquired in blood phantoms with linear-array and curve-array transducers were given. The time-intensity curves corresponding to selected region of interestsequence were demonstrated. It was also shown the time-intensity based decay curves and a decay of ultrasound contrast agent under different ultrasound powers. Conclusion： Several suited from two in vitro phantom models show that the experimental system can be used to f blood perfusion and further clinical studies of microvasculature perfusion.
文摘BACKGROUND Non-invasive differential diagnosis between hepatocellular carcinoma(HCC)and other liver cancer(i.e.cholangiocarcinoma or metastasis)is highly challenging and definitive diagnosis still relies on histological exam.The patterns of enhancement and wash-out of liver nodules can be used to stratify the risk of malignancy only in cirrhotic patients and HCC frequently shows atypical features.Dynamic contrast-enhanced ultrasound(DCEUS)with standardized software could help to overcome these obstacles,providing functional and quantitative parameters and potentially improving accuracy in the evaluation of tumor perfusion.AIM To explore clinical evidence regarding the application of DCEUS in the differential diagnosis of liver nodules.METHODS A comprehensive literature search of clinical studies was performed to identify the parameters of DCEUS that could relate to histological diagnosis.In accordance with the study protocol,a qualitative and quantitative analysis of the evidence was planned.RESULTS Rise time was significantly higher in HCC patients with a standardized mean difference(SMD)of 0.83(95%CI:0.48-1.18).Similarly,other statistically significant parameters were mean transit time local with a SMD of 0.73(95%CI:0.20-1.27),peak enhancement with a SMD of 0.37(95%CI:0.03-0.70),area wash-in area under the curve with a SMD of 0.47(95%CI:0.13-0.81),wash-out area under the curve with a SMD of 0.55(95%CI:0.21-0.89)and wash-in and wash-out area under the curve with SMD of 0.51(95%CI:0.17-0.85).SMD resulted not significant in fall time and wash-in rate,but the latter presented a trend towards greater values in HCC compared to intrahepatic cholangiocarcinoma.CONCLUSION DCEUS could improve non-invasive diagnosis of HCC,leading to less liver biopsy and early treatment.This quantitative analysis needs to be applied on larger cohorts to confirm these preliminary results.
文摘Contrast enhanced ultrasound(CEUS)has been widely implemented in clinical practice because of the enormous quantity of information it provides,along with its low cost,reproducibility,minimal invasiveness,and safety of the secondgeneration ultrasound contrast agents.To overcome the limitation of CEUS given by the subjective evaluation of the contrast enhancement behaviour,quantitative analysis of contrast kinetics with generation of time-intensity curves has been introduced in recent years.The quantification of perfusion parameters[named as dynamic-CEUS(D-CEUS)]has several applications in gastrointestinal neoplastic and inflammatory disorders.However,the limited availability of large studies and the heterogeneity of the technologies employed have precluded the standardisation of D-CEUS,which potentially represents a valuable tool for clinical practice in management of gastrointestinal diseases.In this article,we reviewed the evidence exploring the application of D-CEUS in gastrointestinal diseases,with a special focus on liver,pancreas,and inflammatory bowel diseases.
文摘Examinations with a visualisation of the anatomy and pathology of the gastrointestinal(GI) tract are often necessary for the diagnosis of GI diseases.Traditional radiology played a crucial role for many years.Endoscopy,despite some limitations,remains the main technique in the differential diagnosis and treatment of GI diseases.In the last decades,the introduction of,and advances in,non-invasive cross-sectional imaging modalities,including ultrasound(US),computed tomography(CT),positron-emission tomography(PET),and magnetic resonance imaging,as well as improvements in the resolution of imaging data,the acquisition of 3D images,and the introduction of contrast-enhancement,have modified the approach to the examination of the GI tract.Moreover,additional co-registration techniques,such as PET-CT and PET-MRI,allow multimodal data acquisition with better sensitivity and specificity in the study of tissue pathology.US has had a growing role in the development and application of the techniques for diagnosis and management of GI diseases because it is inexpensive,non-invasive,and more comfortable for the patient,and it has sufficient diagnostic accuracy toprovide the clinician with image data of high temporal and spatial resolution.Moreover,Doppler and contrastenhanced ultrasound(CEUS) add important information about blood flow.This article provides a general review of the current literature regarding imaging modalities used for the evaluation of bowel diseases,highlighting the role of US and recent developments in CEUS.
基金supported by the Natural Science Foundation of Jiangsu University(14KJB320003)
文摘In the current study, we sought to evaluate the diagnostic efficacies of conventional ultrasound（US）, contrastenhanced US（CEUS）, combined US and CEUS and magnetic resonance imaging（MRI） in detecting focal solid breast lesions. Totally 117 patients with 120 BI-RADS category 4A-5 breast lesions were evaluated by conventional US and CEUS, and MRI, respectively. SonoVue was used as contrast agent in CEUS and injected as an intravenous bolus; nodule scan was performed 4 minutes after bolus injection. A specific sonographic quantification software was used to obtain color-coded maps of perfusion parameters for the investigated lesion, namely the time-intensity curve.The pattern of contrast enhancement and related indexes regarding the time-intensity curve were used to describe the lesions, comparatively with pathological results. Histopathologic examination revealed 46 benign and 74 malignant lesions. Sensitivity, specificity, and accuracy of US in detecting malignant breast lesions were 90.14%, 95.92%, and 92.52%, respectively. Meanwhile, CE-MRI showed sensitivity, specificity, and accuracy of 88.73%, 95.92%, and91.67%, respectively. The area under the ROC curve for combined US and CEUS in discriminating benign from malignant breast lesions was 0.936, while that of MRI was 0.923, with no significant difference between them, as well as among groups. The time-intensity curve of malignant hypervascular fibroadenoma and papillary lesions mostly showed a fast-in/fast-out pattern, with no good correlation between them（kappa 〈0.20）. In conclusion, the combined use of conventional US and CEUS displays good agreement with MRI in differentiating benign from malignant breast lesions.
文摘AIM:To study the role of time-intensity curve(TIC) analysis parameters in a complex system of neural networks designed to classify liver tumors.METHODS:We prospectively included 112 patients with hepatocellular carcinoma(HCC)(n = 41),hypervascular(n = 20) and hypovascular(n = 12) liver metastases,hepatic hemangiomas(n = 16) or focal fatty changes(n = 23) who underwent contrast-enhanced ultrasonography in the Research Center of Gastroenterology and Hepatology,Craiova,Romania.We recorded full length movies of all contrast uptake phases and post-processed them offline by selecting two areas of interest(one for the tumor and one for the healthy surrounding parenchyma) and consecutive TIC analysis.The difference in maximum intensities,the time to reaching them and the aspect of the late/portal phase,as quantified by the neural network and a ratio between median intensities of the central and peripheral areas were analyzed by a feed forward back propagation multi-layer neural network which was trained to classify data into five distinct classes,corresponding to each type of liver lesion.RESULTS:The neural network had 94.45% training accuracy(95% CI:89.31%-97.21%) and 87.12% testing accuracy(95% CI:86.83%-93.17%).The automatic classification process registered 93.2% sensitivity,89.7% specificity,94.42% positive predictive value and 87.57% negative predictive value.The artificial neural networks(ANN) incorrectly classified as hemangyomas three HCC cases and two hypervascular metastases,while in turn misclassifying four liver hemangyomas as HCC(one case) and hypervascular metastases(three cases).Comparatively,human interpretation of TICs showed 94.1% sensitivity,90.7% specificity,95.11% positive predictive value and 88.89% negative predictive value.The accuracy and specificity of the ANN diagnosis system was similar to that of human interpretation of the TICs(P = 0.225 and P = 0.451,respectively).Hepatocellular carcinoma cases showed contrast uptake during the arterial phase followed by wash-out in the portal and first seconds of the late phases.For the hypovascular metastases did not show significant contrast uptake during the arterial phase,which resulted in negative differences between the maximum intensities.We registered wash-out in the late phase for most of the hypervascular metastases.Liver hemangiomas had contrast uptake in the arterial phase without agent wash-out in the portallate phases.The focal fatty changes did not show any differences from surrounding liver parenchyma,resulting in similar TIC patterns and extracted parameters.CONCLUSION:Neural network analysis of contrastenhanced ultrasonography-obtained TICs seems a promising field of development for future techniques,providing fast and reliable diagnostic aid for the clinician.
文摘Background Assessment of perfusion in the early period of acute renal failure （ARF） is important,and can not be made by conventional ultrasound.The aim of this study was to prospectively test in a rabbit ARF model whether real-time contrast-enhanced ultrasound （CEUS） can quantitatively evaluate the hemodynamic changes of renal cortex in the early period.Methods The model of ARF was induced in 30 healthy New Zealand white rabbits （2.5-3.0 kg）,by intramuscular injection of 50% glycerin solution （12 ml/kg）.CEUS were performed on right kidneys before,6 and 24 hours after glycerin injection.CEUS quantitative indexes were measured in renal cortex using QLAB software.Comparisons between different stages were performed using paired t test.The sensitivity of CEUS in diagnosing ARF was compared with blood serum urea nitrogen （BUN）,serum creatinine （SCr） level and color Doppler flow imaging （CDFI）.Results Among quantitative indexes,time to peak （TTP） and area under curve （AUC） increased significantly from （5.86±2.57） seconds and （124.4±46.7） dB.s before glycerin injection to （7.66±2.05） seconds and （288.1±64.9） dB.s 6 hours after injection （P 〈0.05）.Slope rate of ascending curve （A） and descending curve （α） decreased slightly from （3.00±1.22） dB/s and （0.19±0.15） 1/s to （2.80±1.45） dB.s and （0.09±0.02） 1/s （P 〈0.05）.Twenty-four hours later,only AUC increased significantly from （124.4±46.7） dB.s to （466.2±52.2） dB.s （P〈0.05）.Conclusion Quantitative indexes of CEUS might be useful in predicting the hemodynamic changes of renal cortex in the early six hours of ARF model.
