The noninvasive ablation of pancreatic cancer with high intensity focused ultrasound(HIFU) energy is received increasingly widespread interest. With rapidly temperature rise to cytotoxic levels within the focal volume...The noninvasive ablation of pancreatic cancer with high intensity focused ultrasound(HIFU) energy is received increasingly widespread interest. With rapidly temperature rise to cytotoxic levels within the focal volume of ultrasound beams, HIFU can selectively ablate a targeted lesion of the pancreas without any damage to surrounding or overlying tissues. Preliminary studies suggest that this approach is technical safe and feasible, and can be used alone or in combination with systemic chemotherapy for the treatment of patients with locally advanced pancreatic cancer. It can effectively alleviate cancer-related abdominal pain, and may confer an additional survival benefit with few significant complications. This review provides a brief overview of HIFU, describes current clinical applications, summarizes characteristics of continuous and pulsed HIFU, and discusses future applications and challenges in the treatment of pancreatic cancer.展开更多
AIM:To evaluate the safety and clinical application of high-intensity focused ultrasound(HIFU)therapy for unresectable pancreatic cancer(PC).METHODS:Thirty PC patients(16 cases in stage III and 14 cases in stage IV)wi...AIM:To evaluate the safety and clinical application of high-intensity focused ultrasound(HIFU)therapy for unresectable pancreatic cancer(PC).METHODS:Thirty PC patients(16 cases in stage III and 14 cases in stage IV)with visualized pancreatic tumors were admitted for HIFU therapy as an optional local therapy in addition to systemic chemotherapy or chemoradiotherapy.Informed consent was obtained.This study began at the end of 2008 and was approved by the ethics committee of our hospital[Institutional Review Board(IRB):890].The HIFU device used was the FEP-BY02(Yuande Bio-Medical Engineering,Beijing,China).RESULTS:The mean tumor size after HIFU therapy changed to 30.9±1.7 mm from 31.7±1.7 mm at pre-therapy.There were no significant changes in tumor size,mean number of treatment sessions(2.7±0.1 mm),or mean total treatment time(2.4±0.1 h).The rate of symptom relief effect was 66.7%.The effectiveness of primary lesion treatment was as follows:complete response,0;partial response,4;stable disease,22;progressive disease,4.Treatment after HIFU therapy included 2 operations,24 chemotherapy treatments,and 4 best supportive care treatments.Adverse events occurred in 10%of cases,namely pseudocyst formation in 2 cases and mild pancreatitis development in 1.However,no severe adverse events occurred in this study.CONCLUSION:We suggest that HIFU therapy is safe and has the potential to be a new method of combination therapy for PC.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 se展开更多
AIM: To establish and validate a simple quantitative assessment method for nonalcoholic fatty liver disease (NAFLD) based on a combination of the ultrasound hepatic/renal ratio and hepatic attenuation rate. METHODS: A...AIM: To establish and validate a simple quantitative assessment method for nonalcoholic fatty liver disease (NAFLD) based on a combination of the ultrasound hepatic/renal ratio and hepatic attenuation rate. METHODS: A total of 170 subjects were enrolled in this study. All subjects were examined by ultrasound and H-1-magnetic resonance spectroscopy (H-1-MRS) on the same day. The ultrasound hepatic/renal echo-intensity ratio and ultrasound hepatic echo-intensity attenuation rate were obtained from ordinary ultrasound images using the MATLAB program. RESULTS: Correlation analysis revealed that the ultrasound hepatic/renal ratio and hepatic echo-intensity attenuation rate were significantly correlated with H-1-MRS liver fat content (ultrasound hepatic/renal ratio: r = 0.952, P = 0.000; hepatic echo-intensity attenuation r = 0.850, P = 0.000). The equation for predicting liver fat content by ultrasound (quantitative ultrasound model) is: liver fat content (%) = 61.519 x ultrasound hepatic/renal ratio + 167.701 x hepatic echo-intensity attenuation rate -26.736. Spearman correlation analysis revealed that the liver fat content ratio of the quantitative ultrasound model was positively correlated with serum alanine aminotransferase, aspartate aminotransferase, and triglyceride, but negatively correlated with high density lipoprotein cholesterol. Receiver operating characteristic curve analysis revealed that the optimal point for diagnosing fatty liver was 9.15% in the quantitative ultrasound model. Furthermore, in the quantitative ultrasound model, fatty liver diagnostic sensitivity and specificity were 94.7% and 100.0%, respectively, showing that the quantitative ultrasound model was better than conventional ultrasound methods or the combined ultrasound hepatic/renal ratio and hepatic echo-intensity attenuation rate. If the 1H-MRS liver fat content had a value < 15%, the sensitivity and specificity of the ultrasound quantitative model would be 81.4% and 100%, which still shows that using the model is better than the othe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
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
文摘The noninvasive ablation of pancreatic cancer with high intensity focused ultrasound(HIFU) energy is received increasingly widespread interest. With rapidly temperature rise to cytotoxic levels within the focal volume of ultrasound beams, HIFU can selectively ablate a targeted lesion of the pancreas without any damage to surrounding or overlying tissues. Preliminary studies suggest that this approach is technical safe and feasible, and can be used alone or in combination with systemic chemotherapy for the treatment of patients with locally advanced pancreatic cancer. It can effectively alleviate cancer-related abdominal pain, and may confer an additional survival benefit with few significant complications. This review provides a brief overview of HIFU, describes current clinical applications, summarizes characteristics of continuous and pulsed HIFU, and discusses future applications and challenges in the treatment of pancreatic cancer.
基金Supported by The cancer research project group of Tokyo Medical University
文摘AIM:To evaluate the safety and clinical application of high-intensity focused ultrasound(HIFU)therapy for unresectable pancreatic cancer(PC).METHODS:Thirty PC patients(16 cases in stage III and 14 cases in stage IV)with visualized pancreatic tumors were admitted for HIFU therapy as an optional local therapy in addition to systemic chemotherapy or chemoradiotherapy.Informed consent was obtained.This study began at the end of 2008 and was approved by the ethics committee of our hospital[Institutional Review Board(IRB):890].The HIFU device used was the FEP-BY02(Yuande Bio-Medical Engineering,Beijing,China).RESULTS:The mean tumor size after HIFU therapy changed to 30.9±1.7 mm from 31.7±1.7 mm at pre-therapy.There were no significant changes in tumor size,mean number of treatment sessions(2.7±0.1 mm),or mean total treatment time(2.4±0.1 h).The rate of symptom relief effect was 66.7%.The effectiveness of primary lesion treatment was as follows:complete response,0;partial response,4;stable disease,22;progressive disease,4.Treatment after HIFU therapy included 2 operations,24 chemotherapy treatments,and 4 best supportive care treatments.Adverse events occurred in 10%of cases,namely pseudocyst formation in 2 cases and mild pancreatitis development in 1.However,no severe adverse events occurred in this study.CONCLUSION:We suggest that HIFU therapy is safe and has the potential to be a new method of combination therapy for PC.
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 se
文摘AIM: To establish and validate a simple quantitative assessment method for nonalcoholic fatty liver disease (NAFLD) based on a combination of the ultrasound hepatic/renal ratio and hepatic attenuation rate. METHODS: A total of 170 subjects were enrolled in this study. All subjects were examined by ultrasound and H-1-magnetic resonance spectroscopy (H-1-MRS) on the same day. The ultrasound hepatic/renal echo-intensity ratio and ultrasound hepatic echo-intensity attenuation rate were obtained from ordinary ultrasound images using the MATLAB program. RESULTS: Correlation analysis revealed that the ultrasound hepatic/renal ratio and hepatic echo-intensity attenuation rate were significantly correlated with H-1-MRS liver fat content (ultrasound hepatic/renal ratio: r = 0.952, P = 0.000; hepatic echo-intensity attenuation r = 0.850, P = 0.000). The equation for predicting liver fat content by ultrasound (quantitative ultrasound model) is: liver fat content (%) = 61.519 x ultrasound hepatic/renal ratio + 167.701 x hepatic echo-intensity attenuation rate -26.736. Spearman correlation analysis revealed that the liver fat content ratio of the quantitative ultrasound model was positively correlated with serum alanine aminotransferase, aspartate aminotransferase, and triglyceride, but negatively correlated with high density lipoprotein cholesterol. Receiver operating characteristic curve analysis revealed that the optimal point for diagnosing fatty liver was 9.15% in the quantitative ultrasound model. Furthermore, in the quantitative ultrasound model, fatty liver diagnostic sensitivity and specificity were 94.7% and 100.0%, respectively, showing that the quantitative ultrasound model was better than conventional ultrasound methods or the combined ultrasound hepatic/renal ratio and hepatic echo-intensity attenuation rate. If the 1H-MRS liver fat content had a value < 15%, the sensitivity and specificity of the ultrasound quantitative model would be 81.4% and 100%, which still shows that using the model is better than the othe
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.
