BACKGROUND: AND PURPOSE: The measurement of relative cerebral blood volume (rCBV) and the volume transfer constant (K(trans)) by means of dynamic contrast-enhanced (DCE) perfusion MR imaging (pMRI) can be useful in ch...BACKGROUND: AND PURPOSE: The measurement of relative cerebral blood volume (rCBV) and the volume transfer constant (K(trans)) by means of dynamic contrast-enhanced (DCE) perfusion MR imaging (pMRI) can be useful in characterizing brain tumors. The purpose of our study was to evaluate the utility of these measurements in differentiating typical meningiomas and atypical meningiomas. METHODS: Fifteen patients with pathologically confirmed typical meningiomas and seven with atypical meningiomas underwent conventional imaging and DCE pMRI before resection.rCBV measurements were calculated by using standard intravascular展开更多
BACKGROUND It is of vital importance to find radiologic biomarkers that can accurately predict treatment response. Usually, the initiation of antiangiogenic therapy causes a rapid decrease in the contrast enhancing tu...BACKGROUND It is of vital importance to find radiologic biomarkers that can accurately predict treatment response. Usually, the initiation of antiangiogenic therapy causes a rapid decrease in the contrast enhancing tumor. However, the treatment response is observed only in a fraction of patients due to the partial radiological response secondary to stabilization of abnormal vessels which does not essentially indicate a true antitumor effect. Perfusion-weighted magnetic resonance imaging(PWMRI) techniques have shown implicitness as a strong imaging biomarker for gliomas since they give hemodynamic information of blood vessels. Hence, there is a rapid expansion of PW-MRI related studies and clinical applications.AIM To determine the diagnostic performance of PW-MRI techniques including:(A)dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI); and(B)dynamic susceptibility contrast magnetic resonance imaging(DSC-MRI) for evaluating response to antiangiogenic therapy in patients with recurrent gliomas.METHODS Databases such as PubMed(MEDLINE included), EMBASE, and Google Scholar were searched for relevant original articles. The included studies were assessed for methodological quality with the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Medical imaging follow-up or histopathological analysis was used as the reference standard. The data were extracted by two reviewers independently, and then the sensitivity, specificity, summary receiver operating characteristic curve, area under the curve(AUC), and heterogeneity were calculated using Meta-Disc 1.4 software.RESULTS This study analyzed a total of six articles. The overall sensitivity for DCE-MRI and DSC-MRI was 0.69 [95% confidence interval(CI): 0.53-0.82], and the specificity was 0.99(95%CI: 0.93-1) by a random effects model(DerSimonianeeLaird model). The likelihood ratio(LR) +, LR-, and diagnostic odds ratio(DOR)were 12.84(4.54-36.28), 0.35(0.22-0.53), and 24.44(7.19-83.06), respectively. The AUC(± SE) was 0.9921(± 0.0120), and the Q* index(± SE) was 0.9640(± 0.0323).For DSC-MRI, the sensitivity was 0.73, the specificity was 0.98, the LR+ was 7.82,the LR-was 0.32, the DOR was 31.65, the AUC(± SE) was 0.9925(± 0.0132), and the Q* index was 0.9649(± 0.0363). For DCE-MRI, the sensitivity was 0.41, the specificity was 0.97, the LR+ was 5.34, the LR-was 0.71, the DOR was 8.76, the AUC(± SE) was 0.9922(± 0.2218), and the Q* index was 0.8935(± 0.3037).CONCLUSION This meta-analysis demonstrated a beneficial value of PW-MRI(DSC-MRI and DCE-MRI) in monitoring the response of recurrent gliomas to antiangiogenic therapy, with reasonable sensitivity, specificity, +LR, and-LR.展开更多
AIM:To investigate intra-operator variability of semiquantitative perfusion parameters using dynamic contrast-enhanced ultrasonography(DCE-US),following bolus injections of SonoVue.METHODS:The in vitro experiments w...AIM:To investigate intra-operator variability of semiquantitative perfusion parameters using dynamic contrast-enhanced ultrasonography(DCE-US),following bolus injections of SonoVue.METHODS:The in vitro experiments were conducted using three in-house sets up based on pumping a fluid through a phantom placed in a water tank.In the in vivo experiments,B16F10 melanoma cells were xenografted to five nude mice.Both in vitro and in vivo,images were acquired following bolus injections of the ultrasound contrast agent SonoVue(Bracco,Milan,Italy) and using a Toshiba Aplio ultrasound scanner connected to a 2.9-5.8 MHz linear transducer(PZT,PLT 604AT probe)(Toshiba,Japan) allowing harmonic imaging("Vascular Recognition Imaging") involving linear raw data.A mathematical model based on the dye-dilution theory was developed by the Gustave Roussy Institute,Villejuif,France and used to evaluate seven perfusion parameters from time-intensity curves.Intra-operator variability analyses were based on determining perfusion parameter coefficients of variation(CV).RESULTS:In vitro,different volumes of SonoVue were tested with the three phantoms:intra-operator variability was found to range from 2.33% to 23.72%.In vivo,experiments were performed on tumor tissues and perfusion parameters exhibited values ranging from 1.48% to 29.97%.In addition,the area under the curve(AUC) and the area under the wash-out(AUWO) were two of the parameters of great interest since throughout in vitro and in vivo experiments their variability was lower than 15.79%.CONCLUSION:AUC and AUWO appear to be the most reliable parameters for assessing tumor perfusion using DCE-US as they exhibited the lowest CV values.展开更多
Esophageal cancer is known as one of the malignant cancers with poor prognosis.To improve the outcome,combined multimodality treatment is attempted.On the other hand,advances in genomics and other“omic”technologies ...Esophageal cancer is known as one of the malignant cancers with poor prognosis.To improve the outcome,combined multimodality treatment is attempted.On the other hand,advances in genomics and other“omic”technologies are paving way to the patient-oriented treatment called“personalized”or“precision”medicine.Recent advancements of imaging techniques such as functional imaging make it possible to use imaging features as biomarker for diagnosis,treatment response,and prognosis in cancer treatment.In this review,we will discuss how we can use imaging derived tumor features as biomarker for the treatment of esophageal cancer.展开更多
Nuclearmagnetic resonance imaging of breasts often presents complex backgrounds.Breast tumors exhibit varying sizes,uneven intensity,and indistinct boundaries.These characteristics can lead to challenges such as low a...Nuclearmagnetic resonance imaging of breasts often presents complex backgrounds.Breast tumors exhibit varying sizes,uneven intensity,and indistinct boundaries.These characteristics can lead to challenges such as low accuracy and incorrect segmentation during tumor segmentation.Thus,we propose a two-stage breast tumor segmentation method leveraging multi-scale features and boundary attention mechanisms.Initially,the breast region of interest is extracted to isolate the breast area from surrounding tissues and organs.Subsequently,we devise a fusion network incorporatingmulti-scale features and boundary attentionmechanisms for breast tumor segmentation.We incorporate multi-scale parallel dilated convolution modules into the network,enhancing its capability to segment tumors of various sizes through multi-scale convolution and novel fusion techniques.Additionally,attention and boundary detection modules are included to augment the network’s capacity to locate tumors by capturing nonlocal dependencies in both spatial and channel domains.Furthermore,a hybrid loss function with boundary weight is employed to address sample class imbalance issues and enhance the network’s boundary maintenance capability through additional loss.Themethod was evaluated using breast data from 207 patients at RuijinHospital,resulting in a 6.64%increase in Dice similarity coefficient compared to the benchmarkU-Net.Experimental results demonstrate the superiority of the method over other segmentation techniques,with fewer model parameters.展开更多
Dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)enables tumor vascular physiology to be assessed.Within the tumor tissue,contrast agents(gadolinium chelates)extravasate from intravascular into the extrava...Dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)enables tumor vascular physiology to be assessed.Within the tumor tissue,contrast agents(gadolinium chelates)extravasate from intravascular into the extravascular extracellular space(EES),which results in a signal increase on T1-weighted MRI.The rate of contrast agents extravasation to EES in the tumor tissue is determined by vessel leakiness and blood flow.Thus,the signal measured on DCE-MRI represents a combination of permeability and perfusion.The semi-quantitative analysis is based on the calculation of heuristic parameters that can be extracted from signal intensity-time curves.These enhancing curves can also be deconvoluted by mathematical modeling to extract quantitative parameters that may reflect tumor perfusion,vascular volume,vessel permeability and angiogenesis.Because hepatocellular carcinoma(HCC)is a hypervascular tumor,many emerging therapies focused on the inhibition of angiogenesis.DCE-MRI combined with a pharmacokinetic model allows us to produce highly reproducible and reliable parametric maps of quantitative parameters in HCC.Successful therapies change quantitative parameters of DCE-MRI,which may be used as early indicators of tumor response to anti-angiogenesis agents that modulate tumor vasculature.In the setting of clinical trials,DCE-MRI may provide relevant clinical information on the pharmacodynamic and biologic effects of novel drugs,monitor treatment response and predict survival outcome in HCC patients.展开更多
目的比较多参数三维假连续式动脉自旋标记灌注成像(3D p CASL)与动态磁敏感增强灌注成像(DSC PWI)对短暂性脑缺血发作(TIA)责任病灶的检出率。方法比较39例临床诊断TIA患者,并在首次发作24 h内进行磁共振检查。扫描序列包括常规头颅MR...目的比较多参数三维假连续式动脉自旋标记灌注成像(3D p CASL)与动态磁敏感增强灌注成像(DSC PWI)对短暂性脑缺血发作(TIA)责任病灶的检出率。方法比较39例临床诊断TIA患者,并在首次发作24 h内进行磁共振检查。扫描序列包括常规头颅MR成像、MRA(MRA),DWI、3D p CASL(选取两个标记延迟时间post-labeling time,PLD,PLD=1.5 s及PLD=2.5 s),DSC PWI。后处理获取3D p CASL的脑血流(CBF)图像和DSC PWI的Tmax图像。比较不同灌注方法与MRA及DWI结合法对于缺血病灶检出率和缺血面积。结果 TIA患者的缺血病灶检出率,3D p CASL(PLD1.5 s及PLD2.5 s)的CBF图像与DSC PWI Tmax对比无差异;3D p CASL(PLD1.5 s)的CBF图像对于缺血的检出率高于MRA结合DWI法;DSC PWI Tmax、3D p CASL(PLD2.5 s)CBF与MRA结合DWI法无差异。显示低灌注面积,3D p CASL(PLD1.5 s)的CBF图像显示的面积最大,其次是DSC PWI Tmax,而3D p CASL(PLD2.5 s)的CBF图像显示的低灌注面积最小。结论 3D p CASL脑灌注成像技术无创、快速、可重复性强,推荐作为临床可疑TIA患者的影像筛查手段,不同PLD的3D p CASL序列对于病灶的检出及缺血面积的显示有差异,选择较短PLD有可能提高病灶的检出率。展开更多
文摘BACKGROUND: AND PURPOSE: The measurement of relative cerebral blood volume (rCBV) and the volume transfer constant (K(trans)) by means of dynamic contrast-enhanced (DCE) perfusion MR imaging (pMRI) can be useful in characterizing brain tumors. The purpose of our study was to evaluate the utility of these measurements in differentiating typical meningiomas and atypical meningiomas. METHODS: Fifteen patients with pathologically confirmed typical meningiomas and seven with atypical meningiomas underwent conventional imaging and DCE pMRI before resection.rCBV measurements were calculated by using standard intravascular
文摘BACKGROUND It is of vital importance to find radiologic biomarkers that can accurately predict treatment response. Usually, the initiation of antiangiogenic therapy causes a rapid decrease in the contrast enhancing tumor. However, the treatment response is observed only in a fraction of patients due to the partial radiological response secondary to stabilization of abnormal vessels which does not essentially indicate a true antitumor effect. Perfusion-weighted magnetic resonance imaging(PWMRI) techniques have shown implicitness as a strong imaging biomarker for gliomas since they give hemodynamic information of blood vessels. Hence, there is a rapid expansion of PW-MRI related studies and clinical applications.AIM To determine the diagnostic performance of PW-MRI techniques including:(A)dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI); and(B)dynamic susceptibility contrast magnetic resonance imaging(DSC-MRI) for evaluating response to antiangiogenic therapy in patients with recurrent gliomas.METHODS Databases such as PubMed(MEDLINE included), EMBASE, and Google Scholar were searched for relevant original articles. The included studies were assessed for methodological quality with the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Medical imaging follow-up or histopathological analysis was used as the reference standard. The data were extracted by two reviewers independently, and then the sensitivity, specificity, summary receiver operating characteristic curve, area under the curve(AUC), and heterogeneity were calculated using Meta-Disc 1.4 software.RESULTS This study analyzed a total of six articles. The overall sensitivity for DCE-MRI and DSC-MRI was 0.69 [95% confidence interval(CI): 0.53-0.82], and the specificity was 0.99(95%CI: 0.93-1) by a random effects model(DerSimonianeeLaird model). The likelihood ratio(LR) +, LR-, and diagnostic odds ratio(DOR)were 12.84(4.54-36.28), 0.35(0.22-0.53), and 24.44(7.19-83.06), respectively. The AUC(± SE) was 0.9921(± 0.0120), and the Q* index(± SE) was 0.9640(± 0.0323).For DSC-MRI, the sensitivity was 0.73, the specificity was 0.98, the LR+ was 7.82,the LR-was 0.32, the DOR was 31.65, the AUC(± SE) was 0.9925(± 0.0132), and the Q* index was 0.9649(± 0.0363). For DCE-MRI, the sensitivity was 0.41, the specificity was 0.97, the LR+ was 5.34, the LR-was 0.71, the DOR was 8.76, the AUC(± SE) was 0.9922(± 0.2218), and the Q* index was 0.8935(± 0.3037).CONCLUSION This meta-analysis demonstrated a beneficial value of PW-MRI(DSC-MRI and DCE-MRI) in monitoring the response of recurrent gliomas to antiangiogenic therapy, with reasonable sensitivity, specificity, +LR, and-LR.
文摘AIM:To investigate intra-operator variability of semiquantitative perfusion parameters using dynamic contrast-enhanced ultrasonography(DCE-US),following bolus injections of SonoVue.METHODS:The in vitro experiments were conducted using three in-house sets up based on pumping a fluid through a phantom placed in a water tank.In the in vivo experiments,B16F10 melanoma cells were xenografted to five nude mice.Both in vitro and in vivo,images were acquired following bolus injections of the ultrasound contrast agent SonoVue(Bracco,Milan,Italy) and using a Toshiba Aplio ultrasound scanner connected to a 2.9-5.8 MHz linear transducer(PZT,PLT 604AT probe)(Toshiba,Japan) allowing harmonic imaging("Vascular Recognition Imaging") involving linear raw data.A mathematical model based on the dye-dilution theory was developed by the Gustave Roussy Institute,Villejuif,France and used to evaluate seven perfusion parameters from time-intensity curves.Intra-operator variability analyses were based on determining perfusion parameter coefficients of variation(CV).RESULTS:In vitro,different volumes of SonoVue were tested with the three phantoms:intra-operator variability was found to range from 2.33% to 23.72%.In vivo,experiments were performed on tumor tissues and perfusion parameters exhibited values ranging from 1.48% to 29.97%.In addition,the area under the curve(AUC) and the area under the wash-out(AUWO) were two of the parameters of great interest since throughout in vitro and in vivo experiments their variability was lower than 15.79%.CONCLUSION:AUC and AUWO appear to be the most reliable parameters for assessing tumor perfusion using DCE-US as they exhibited the lowest CV values.
文摘Esophageal cancer is known as one of the malignant cancers with poor prognosis.To improve the outcome,combined multimodality treatment is attempted.On the other hand,advances in genomics and other“omic”technologies are paving way to the patient-oriented treatment called“personalized”or“precision”medicine.Recent advancements of imaging techniques such as functional imaging make it possible to use imaging features as biomarker for diagnosis,treatment response,and prognosis in cancer treatment.In this review,we will discuss how we can use imaging derived tumor features as biomarker for the treatment of esophageal cancer.
基金funded by the National Natural Foundation of China under Grant No.61172167the Science Fund Project of Heilongjiang Province(LH2020F035).
文摘Nuclearmagnetic resonance imaging of breasts often presents complex backgrounds.Breast tumors exhibit varying sizes,uneven intensity,and indistinct boundaries.These characteristics can lead to challenges such as low accuracy and incorrect segmentation during tumor segmentation.Thus,we propose a two-stage breast tumor segmentation method leveraging multi-scale features and boundary attention mechanisms.Initially,the breast region of interest is extracted to isolate the breast area from surrounding tissues and organs.Subsequently,we devise a fusion network incorporatingmulti-scale features and boundary attentionmechanisms for breast tumor segmentation.We incorporate multi-scale parallel dilated convolution modules into the network,enhancing its capability to segment tumors of various sizes through multi-scale convolution and novel fusion techniques.Additionally,attention and boundary detection modules are included to augment the network’s capacity to locate tumors by capturing nonlocal dependencies in both spatial and channel domains.Furthermore,a hybrid loss function with boundary weight is employed to address sample class imbalance issues and enhance the network’s boundary maintenance capability through additional loss.Themethod was evaluated using breast data from 207 patients at RuijinHospital,resulting in a 6.64%increase in Dice similarity coefficient compared to the benchmarkU-Net.Experimental results demonstrate the superiority of the method over other segmentation techniques,with fewer model parameters.
文摘Dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)enables tumor vascular physiology to be assessed.Within the tumor tissue,contrast agents(gadolinium chelates)extravasate from intravascular into the extravascular extracellular space(EES),which results in a signal increase on T1-weighted MRI.The rate of contrast agents extravasation to EES in the tumor tissue is determined by vessel leakiness and blood flow.Thus,the signal measured on DCE-MRI represents a combination of permeability and perfusion.The semi-quantitative analysis is based on the calculation of heuristic parameters that can be extracted from signal intensity-time curves.These enhancing curves can also be deconvoluted by mathematical modeling to extract quantitative parameters that may reflect tumor perfusion,vascular volume,vessel permeability and angiogenesis.Because hepatocellular carcinoma(HCC)is a hypervascular tumor,many emerging therapies focused on the inhibition of angiogenesis.DCE-MRI combined with a pharmacokinetic model allows us to produce highly reproducible and reliable parametric maps of quantitative parameters in HCC.Successful therapies change quantitative parameters of DCE-MRI,which may be used as early indicators of tumor response to anti-angiogenesis agents that modulate tumor vasculature.In the setting of clinical trials,DCE-MRI may provide relevant clinical information on the pharmacodynamic and biologic effects of novel drugs,monitor treatment response and predict survival outcome in HCC patients.
文摘目的比较多参数三维假连续式动脉自旋标记灌注成像(3D p CASL)与动态磁敏感增强灌注成像(DSC PWI)对短暂性脑缺血发作(TIA)责任病灶的检出率。方法比较39例临床诊断TIA患者,并在首次发作24 h内进行磁共振检查。扫描序列包括常规头颅MR成像、MRA(MRA),DWI、3D p CASL(选取两个标记延迟时间post-labeling time,PLD,PLD=1.5 s及PLD=2.5 s),DSC PWI。后处理获取3D p CASL的脑血流(CBF)图像和DSC PWI的Tmax图像。比较不同灌注方法与MRA及DWI结合法对于缺血病灶检出率和缺血面积。结果 TIA患者的缺血病灶检出率,3D p CASL(PLD1.5 s及PLD2.5 s)的CBF图像与DSC PWI Tmax对比无差异;3D p CASL(PLD1.5 s)的CBF图像对于缺血的检出率高于MRA结合DWI法;DSC PWI Tmax、3D p CASL(PLD2.5 s)CBF与MRA结合DWI法无差异。显示低灌注面积,3D p CASL(PLD1.5 s)的CBF图像显示的面积最大,其次是DSC PWI Tmax,而3D p CASL(PLD2.5 s)的CBF图像显示的低灌注面积最小。结论 3D p CASL脑灌注成像技术无创、快速、可重复性强,推荐作为临床可疑TIA患者的影像筛查手段,不同PLD的3D p CASL序列对于病灶的检出及缺血面积的显示有差异,选择较短PLD有可能提高病灶的检出率。
