In many areas of oncology, dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) has proven to be a clinically useful, non-invasive functional imaging technique to quantify tumor vasculature and tumor perfusio...In many areas of oncology, dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) has proven to be a clinically useful, non-invasive functional imaging technique to quantify tumor vasculature and tumor perfusion characteristics. Tumor angiogenesis is an essential process for tumor growth, proliferation, and metastasis. Malignant lesions demonstrate rapid extravasation of contrast from the intravascular space to the capillary bed due to leaky capillaries associated with tumor neovascularity. DCE-MRI has the potential to provide information regarding blood flow, areas of hypoperfusion, and variations in endothelial permeability and microvessel density to aid treatment selection, enable frequent monitoring during treatment and assess response to targeted therapy following treatment. This review will discuss the current status of DCE-MRI in cancer imaging, with a focus on its use in imaging prostate malignancies as well as weaknesses that limit its widespread clinical use. The latest techniques for quantification of DCE-MRI parameters will be reviewed and compared.展开更多
Objective： To evaluate the feasibility of dynamic contrast-enhanced magnetic resonance imaging（DCEMRI） for predicting tumor response to radiotherapy in patients with suspected primary central nervous system（CNS） ...Objective： To evaluate the feasibility of dynamic contrast-enhanced magnetic resonance imaging（DCEMRI） for predicting tumor response to radiotherapy in patients with suspected primary central nervous system（CNS） germ cell tumors（GCTs）.Methods： DCE-MRI parameters of 35 patients with suspected primary CNS GCTs were obtained prior to diagnostic radiation, using the Tofts and Kermode model. Radiosensitivity was determined in tumors diagnosed 2 weeks after radiation by observing changes in tumor size and markers as a response to MRI. Taking radiosensitivity as the gold standard, the cut-off value of DCE-MRI parameters was measured by receiver operating characteristic（ROC） curve. Diagnostic accuracy of DCE-MRI parameters for predicting radiosensitivity was evaluated by ROC curve.Results： A significant elevation in transfer constant（K^trans） and extravascular extracellular space（Ve）（P=0.000）, as well as a significant reduction in rate constant（Kep）（P=0.000） was observed in tumors. K^trans, relative K^trans, and relative Kep of the responsive group were significantly higher than non-responsive groups. No significant difference was found in Kep, Ve, and relative Ve between the two groups. Relative K^trans showed the best diagnostic value in predicting radiosensitivity with a sensitivity of 100%, specificity of 91.7%, positive predictive value（PPV） of 95.8%, and negative predictive value（NPV） of 100%.Conclusions： Relative K^trans appeared promising in predicting tumor response to radiation therapy（RT）. It is implied that DCE-MRI pre-treatment is a requisite step in diagnostic procedures and a novel and reliable approach to guide clinical choice of RT.展开更多
Proton magnetic resonance spectroscopy and diffusion tensor imaging are non-invasive techniques used to detect metabolites and water diffusion in vivo. Previous studies have confirmed a positive correlation of individ...Proton magnetic resonance spectroscopy and diffusion tensor imaging are non-invasive techniques used to detect metabolites and water diffusion in vivo. Previous studies have confirmed a positive correlation of individual fractional anisotropy values with N-acetylaspartate/creatine and N-acetylaspartate/choline ratios in tumors, edema, and normal white matter. This study divided the brain parenchyma into tumor, pedtumoral edema, and normal-appearing white matter according to MRI data, and analyzed the correlation of metabolites with water molecular diffusion. Results demonstrated that in normal-appearing white matter, N-acetylaspartate/creatine ratios were positively correlated with fractional anisotropy values, negatively correlated with radial diffusivities, and positively correlated with maximum eigenvalues. Maximum eigenvalues and radial diffusivities in peritumoral edema showed a negative correlation with choline, N-acetylaspartate, and creatine. Radial diffusivities in tumor demonstrated a negative correlation with choline. These data suggest that the relationship between metabolism and structure is markedly changed from normal white matter to peritumoral edema and tumor. Neural metabolism in the peritumoral edema area decreased with expanding extracellular space. The normal relationship of neural function and microstructure disappeared in the tumor region.展开更多
目的：研究Gd-EOB-DTPA显示胆管系统的能力与特性,比较Gd-EOB-DTPA增强磁共振胆管成像（EOB-MRC）与磁共振胆胰管成像（MRCP）的胆管系统结构显示情况。方法：16例肝占位且未侵犯胆管系统的病例资料纳入研究。所有患者均先行MRCP扫描和...目的：研究Gd-EOB-DTPA显示胆管系统的能力与特性,比较Gd-EOB-DTPA增强磁共振胆管成像（EOB-MRC）与磁共振胆胰管成像（MRCP）的胆管系统结构显示情况。方法：16例肝占位且未侵犯胆管系统的病例资料纳入研究。所有患者均先行MRCP扫描和抑脂3D GRE T1WI（VIBE）扫描,注射Gd-EOB-DTPA后约30min行抑脂3DVIBE胆管成像。统计Gd-EOB-DTPA增强前后抑脂3D VIBE胆管信号变化、胆管-肝脏对比噪声比（CNR）绝对值变化和EOB-MRC、MRCP及两者结合胆管系统结构显示的评分情况。结果：Gd-EOB-DTPA增强前和增强后30min胆总管信号强度分别为113.27±38.20和595.31±34.62,胆囊信号强度分别为182.73±113.45和684.20±153.41;胆总管-肝脏CNR绝对值分别为131.13±33.29和86.56±48.44,胆囊-肝脏CNR绝对值分别为105.91±45.96和125.59±50.45;Gd-EOB-DTPA增强前后胆总管和胆囊内的信号强度之间差异有显著性意义（P〈0.001）,Gd-EOB-DTPA增强前后胆总管-肝脏CNR绝对值差异有显著性意义（P〈0.001）,胆囊-肝脏CNR绝对值变化差异无统计学意义（P〉0.05）。胆管系统结构显示情况评分：EOB-MRC与MRCP对胆总管、肝总管、左右肝管及胆囊管的显示大致相仿,EOB-MRC与MRCP结合时评分高于前两者,但三者间差异均无统计学意义（P〉0.05）;胆囊的可见度EOB-MRC评分为3.09±1.00,低于MRCP的评分（3.76±0.44）,两者结合评分为3.82±0.39,三项评分差异存在统计学意义（P〈0.01）;肝内二级胆管的可见度EOB-MRC评分为2.25±1.33,高于MRCP的评分（1.67±1.33）,但差异无统计学意义,EOB-MRC与MRCP两者结合时肝内二级胆管的可见度评分最高,有2.59±1.22。结论：Gd-EOB-DTPA增强磁共振胆管成像可以满意显示胆管系统,与MRCP互为补充,两者联合应用可进一步提高胆管系统显示,并有望了解胆管系统功能状况。展开更多
目的研究MRI对比剂钆-二乙烯三胺五乙酸(Gd-DTPA)标记骨髓间充质干细胞(BMSC5)的可行性及标记之后体外MR成像示踪的可能性。材料与方法骨髓间充质干细胞由SD大鼠双侧股骨骨髓中获取,培养、传代并纯化细胞,采用临床通用Gd-DTPA增强剂标...目的研究MRI对比剂钆-二乙烯三胺五乙酸(Gd-DTPA)标记骨髓间充质干细胞(BMSC5)的可行性及标记之后体外MR成像示踪的可能性。材料与方法骨髓间充质干细胞由SD大鼠双侧股骨骨髓中获取,培养、传代并纯化细胞,采用临床通用Gd-DTPA增强剂标记骨髓间充质干细胞;透射电子显微镜观察标记情况,并用台盼蓝染色方法及噻唑蓝(MTT)法测定标记细胞的活力及增殖能力;对标记的细胞进行体外7.0 T MR成像。结果透射电子显微镜可清晰观察到Gd-DTPA颗粒大部分存在于骨髓间充质干细胞细胞浆中,少许贴附于细胞膜上。台盼蓝染色方法证实标记之后细胞的存活率没有受到影响,MTT法证实标记之后对BMSCs增殖能力没有影响。体外试管扫描示标记细胞呈高T1WI信号强度,并且持续时间较久。结论 Gd-DTPA标记细胞之后,BMSCs的活性及增殖能力没有受到影响,并且透射电镜结果证实Gd-DTPA颗粒存在于细胞胞浆内,在细胞胞膜上也有Gd-DTPA颗粒存在。标记的BMSCs在体外检测到明显的MRI信号强度改变。Gd-DTPA可以作为一种示踪剂用来MRI示踪研究。展开更多
文摘In many areas of oncology, dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI) has proven to be a clinically useful, non-invasive functional imaging technique to quantify tumor vasculature and tumor perfusion characteristics. Tumor angiogenesis is an essential process for tumor growth, proliferation, and metastasis. Malignant lesions demonstrate rapid extravasation of contrast from the intravascular space to the capillary bed due to leaky capillaries associated with tumor neovascularity. DCE-MRI has the potential to provide information regarding blood flow, areas of hypoperfusion, and variations in endothelial permeability and microvessel density to aid treatment selection, enable frequent monitoring during treatment and assess response to targeted therapy following treatment. This review will discuss the current status of DCE-MRI in cancer imaging, with a focus on its use in imaging prostate malignancies as well as weaknesses that limit its widespread clinical use. The latest techniques for quantification of DCE-MRI parameters will be reviewed and compared.
基金supported by Beijing Natural Science Foundation(No.7122029)
文摘Objective： To evaluate the feasibility of dynamic contrast-enhanced magnetic resonance imaging（DCEMRI） for predicting tumor response to radiotherapy in patients with suspected primary central nervous system（CNS） germ cell tumors（GCTs）.Methods： DCE-MRI parameters of 35 patients with suspected primary CNS GCTs were obtained prior to diagnostic radiation, using the Tofts and Kermode model. Radiosensitivity was determined in tumors diagnosed 2 weeks after radiation by observing changes in tumor size and markers as a response to MRI. Taking radiosensitivity as the gold standard, the cut-off value of DCE-MRI parameters was measured by receiver operating characteristic（ROC） curve. Diagnostic accuracy of DCE-MRI parameters for predicting radiosensitivity was evaluated by ROC curve.Results： A significant elevation in transfer constant（K^trans） and extravascular extracellular space（Ve）（P=0.000）, as well as a significant reduction in rate constant（Kep）（P=0.000） was observed in tumors. K^trans, relative K^trans, and relative Kep of the responsive group were significantly higher than non-responsive groups. No significant difference was found in Kep, Ve, and relative Ve between the two groups. Relative K^trans showed the best diagnostic value in predicting radiosensitivity with a sensitivity of 100%, specificity of 91.7%, positive predictive value（PPV） of 95.8%, and negative predictive value（NPV） of 100%.Conclusions： Relative K^trans appeared promising in predicting tumor response to radiation therapy（RT）. It is implied that DCE-MRI pre-treatment is a requisite step in diagnostic procedures and a novel and reliable approach to guide clinical choice of RT.
基金supported by the National Natural Science Foundation of China, No. 81171318Shaanxi Provincial Scientific Research Project, No. 2012K13-02-24
文摘Proton magnetic resonance spectroscopy and diffusion tensor imaging are non-invasive techniques used to detect metabolites and water diffusion in vivo. Previous studies have confirmed a positive correlation of individual fractional anisotropy values with N-acetylaspartate/creatine and N-acetylaspartate/choline ratios in tumors, edema, and normal white matter. This study divided the brain parenchyma into tumor, pedtumoral edema, and normal-appearing white matter according to MRI data, and analyzed the correlation of metabolites with water molecular diffusion. Results demonstrated that in normal-appearing white matter, N-acetylaspartate/creatine ratios were positively correlated with fractional anisotropy values, negatively correlated with radial diffusivities, and positively correlated with maximum eigenvalues. Maximum eigenvalues and radial diffusivities in peritumoral edema showed a negative correlation with choline, N-acetylaspartate, and creatine. Radial diffusivities in tumor demonstrated a negative correlation with choline. These data suggest that the relationship between metabolism and structure is markedly changed from normal white matter to peritumoral edema and tumor. Neural metabolism in the peritumoral edema area decreased with expanding extracellular space. The normal relationship of neural function and microstructure disappeared in the tumor region.
文摘目的：研究Gd-EOB-DTPA显示胆管系统的能力与特性,比较Gd-EOB-DTPA增强磁共振胆管成像（EOB-MRC）与磁共振胆胰管成像（MRCP）的胆管系统结构显示情况。方法：16例肝占位且未侵犯胆管系统的病例资料纳入研究。所有患者均先行MRCP扫描和抑脂3D GRE T1WI（VIBE）扫描,注射Gd-EOB-DTPA后约30min行抑脂3DVIBE胆管成像。统计Gd-EOB-DTPA增强前后抑脂3D VIBE胆管信号变化、胆管-肝脏对比噪声比（CNR）绝对值变化和EOB-MRC、MRCP及两者结合胆管系统结构显示的评分情况。结果：Gd-EOB-DTPA增强前和增强后30min胆总管信号强度分别为113.27±38.20和595.31±34.62,胆囊信号强度分别为182.73±113.45和684.20±153.41;胆总管-肝脏CNR绝对值分别为131.13±33.29和86.56±48.44,胆囊-肝脏CNR绝对值分别为105.91±45.96和125.59±50.45;Gd-EOB-DTPA增强前后胆总管和胆囊内的信号强度之间差异有显著性意义（P〈0.001）,Gd-EOB-DTPA增强前后胆总管-肝脏CNR绝对值差异有显著性意义（P〈0.001）,胆囊-肝脏CNR绝对值变化差异无统计学意义（P〉0.05）。胆管系统结构显示情况评分：EOB-MRC与MRCP对胆总管、肝总管、左右肝管及胆囊管的显示大致相仿,EOB-MRC与MRCP结合时评分高于前两者,但三者间差异均无统计学意义（P〉0.05）;胆囊的可见度EOB-MRC评分为3.09±1.00,低于MRCP的评分（3.76±0.44）,两者结合评分为3.82±0.39,三项评分差异存在统计学意义（P〈0.01）;肝内二级胆管的可见度EOB-MRC评分为2.25±1.33,高于MRCP的评分（1.67±1.33）,但差异无统计学意义,EOB-MRC与MRCP两者结合时肝内二级胆管的可见度评分最高,有2.59±1.22。结论：Gd-EOB-DTPA增强磁共振胆管成像可以满意显示胆管系统,与MRCP互为补充,两者联合应用可进一步提高胆管系统显示,并有望了解胆管系统功能状况。
文摘目的研究MRI对比剂钆-二乙烯三胺五乙酸(Gd-DTPA)标记骨髓间充质干细胞(BMSC5)的可行性及标记之后体外MR成像示踪的可能性。材料与方法骨髓间充质干细胞由SD大鼠双侧股骨骨髓中获取,培养、传代并纯化细胞,采用临床通用Gd-DTPA增强剂标记骨髓间充质干细胞;透射电子显微镜观察标记情况,并用台盼蓝染色方法及噻唑蓝(MTT)法测定标记细胞的活力及增殖能力;对标记的细胞进行体外7.0 T MR成像。结果透射电子显微镜可清晰观察到Gd-DTPA颗粒大部分存在于骨髓间充质干细胞细胞浆中,少许贴附于细胞膜上。台盼蓝染色方法证实标记之后细胞的存活率没有受到影响,MTT法证实标记之后对BMSCs增殖能力没有影响。体外试管扫描示标记细胞呈高T1WI信号强度,并且持续时间较久。结论 Gd-DTPA标记细胞之后,BMSCs的活性及增殖能力没有受到影响,并且透射电镜结果证实Gd-DTPA颗粒存在于细胞胞浆内,在细胞胞膜上也有Gd-DTPA颗粒存在。标记的BMSCs在体外检测到明显的MRI信号强度改变。Gd-DTPA可以作为一种示踪剂用来MRI示踪研究。
