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Evaluation of tumor response to antiangiogenic therapy in patients with recurrent gliomas using contrast-enhanced perfusion-weighted magnetic resonance imaging techniques:A meta-analysis 被引量:1
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作者 Akanganyira Kasenene Aju Baidya +1 位作者 Salman Shams Hai-Bo Xu 《World Journal of Meta-Analysis》 2019年第2期51-65,共15页
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
关键词 Glioma perfusion-weighted MAGNETIC RESONANCE imaging DYNAMIC contrastenhanced MAGNETIC RESONANCE imaging DYNAMIC susceptibility contrast MAGNETIC RESONANCE imaging Anti-vascular endothelial growth factor ANTIANGIOGENIC Metaanalysis
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Correlation of MR Perfusion-weighted Imaging of Prostatic Cancer with Tumor Angiogenesis
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作者 张继斌 沈钧康 +1 位作者 许建铭 李晓兵 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2008年第2期133-138,共6页
Objective: MR perfusion-weighted imaging(PWI) has been widely applied in the research of cerebral tumor, benign and malignant musculoskeletal neoplasms and so on. The aim of this study is to explore the application... Objective: MR perfusion-weighted imaging(PWI) has been widely applied in the research of cerebral tumor, benign and malignant musculoskeletal neoplasms and so on. The aim of this study is to explore the application of MR perfusion-weighted imaging in prostatic cancer (Pca), and evaluate the correlation of PWI features with vascular endothelial growth factor (VEGF) and microvessel density (MVD). Methods: Twenty-eight consecutive patients who were diagnosed clinically as prostatic cancer and thirty healthy volunteers were examined by PWI. MVD and VEGF were stained with immunohistochemical methods. Some parameters of PWI, including the steepest slope of signal intensity-time curve (SSmax) and the change in relaxation rate (ΔR2^*peak) at lesions, were analyzed. Correlation analysis was used to determine the relationship between the results of PWI and that of immunohistochemistry. Results: (1) In the healthy volunteers, the steepest slope of signal intensity-time curve (SSmax) and ΔR2^*peak of perfusion curve were: 0.430±0.011, 2.01±0.7 respectively; however, in the prostatic cancer, they were 57.8±5.0, 3.0±0.6 respectively; with significant difference (t=-4.11, 3.28, P〈0.01). (2)The VEGF and MVD expression of twenty-eight Pca patients were significantly higher. Conclusion: On MR perfusion- weighted imaging, SSmax and ΔR2^*peak can reflect MVD and VEGF expression levels in prostatic cancer, suggesting information on tumor angiogenesis. Thus they are beneficial to the diagnosis and treatment of prostatic cancer. 展开更多
关键词 Prostatic cancer(Pca) Magnetic resonance imaging(MRI) perfusion-weighted imagingpwi Vascularendothelial growth factor(VEGF) Microvessel density(MVD)
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Distinctive magnetic resonance imaging features in primary central nervous system lymphoma:A case report
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作者 Li-Hong Liu Han-Wen Zhang +4 位作者 Hong-Bo Zhang Xiao-Lei Liu Hua-Zhen Deng Fan Lin Biao Huang 《World Journal of Radiology》 2023年第9期274-280,共7页
BACKGROUND Primary central nervous system lymphoma(PCNSL)is a rare malignant tumor originating from the lymphatic hematopoietic system.It exhibits unique imaging manifestations due to its biological characteristics.CA... BACKGROUND Primary central nervous system lymphoma(PCNSL)is a rare malignant tumor originating from the lymphatic hematopoietic system.It exhibits unique imaging manifestations due to its biological characteristics.CASE SUMMARY Magnetic resonance imaging(MRI)with diffusion-weighted imaging(DWI),perfusion-weighted imaging(PWI),and magnetic resonance spectroscopy was performed.The imaging findings showed multiple space-occupying lesions with low signal on T1-weighted imaging,uniform high signal on T2-weighted imaging,and obvious enhancement on contrast-enhanced scans.DWI revealed diffusion restriction,PWI demonstrated hypoperfusion,and spectroscopy showed elevated choline peak and decreased N-acetylaspartic acid.The patient's condition significantly improved after hormone shock therapy.CONCLUSION This case highlights the distinctive imaging features of PCNSL and their importance in accurate diagnosis and management. 展开更多
关键词 Primary central nervous system lymphoma Primary central nervous system lymphoma Diffusion-weighted imaging perfusion-weighted imaging Magnetic resonance imaging Case report
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Advanced imaging techniques in the therapeutic response of transarterial chemoembolization for hepatocellular carcinoma 被引量:12
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作者 Ke Yang Xiao-Ming Zhang +2 位作者 Lin Yang Hao Xu Juan Peng 《World Journal of Gastroenterology》 SCIE CAS 2016年第20期4835-4847,共13页
Hepatocellular carcinoma(HCC) is one of the major causes of morbidity and mortality in patients with chronic liver disease. Transarterial chemoembolization(TACE) can significantly improve the survival rate of patients... Hepatocellular carcinoma(HCC) is one of the major causes of morbidity and mortality in patients with chronic liver disease. Transarterial chemoembolization(TACE) can significantly improve the survival rate of patients with HCC and is the first treatment choice for patients who are not suitable for surgical resections. The evaluation of the response to TACE treatment affects not only the assessment of the therapy efficacy but also the development of the next step in the treatment plan. The use of imaging to examine changes in tumor volume to assess the response of solid tumors to treatment has been controversial. In recent years, the emergence of new imaging technology has made it possible to observe the response of tumors to treatment prior to any morphological changes. In this article, the advances in studies reporting the use of computed tomography perfusion imaging, diffusionweighted magnetic resonance imaging(MRI), intravoxel incoherent motion, diffusion kurtosis imaging, magnetic resonance spectroscopy, magnetic resonance perfusionweighted imaging, blood oxygen level-dependent MRI, positron emission tomography(PET)/computed tomography and PET/MRI to assess the TACE treatment response are reviewed. 展开更多
关键词 Blood oxygen level-dependent Computed tomography perfusion imaging CHEMOEMBOLIZATION Diffusion kurtosis imaging Diffusion-weighted imaging Hepatocellular carcinoma Magnetic resonance perfusion-weighted imaging Intravoxel incoherent motion Magnetic resonance spectroscopy
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Erythropoietin reduces apoptosis of brain tissue cells in rats after cerebral ischemia/reperfusion injury:a characteristic analysis using magnetic resonance imaging 被引量:14
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作者 Chun-juan Jiang Zhong-juan Wang +3 位作者 Yan-jun Zhao Zhui-yang Zhang Jing-jing Tao Jian-yong Ma 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第9期1450-1455,共6页
Some in vitro experiments have shown that erythropoietin (EPO) increases resistance to apoptosis and facilitates neuronal survival follow- ing cerebral ischemia. However, results from in vivo studies are rarely repo... Some in vitro experiments have shown that erythropoietin (EPO) increases resistance to apoptosis and facilitates neuronal survival follow- ing cerebral ischemia. However, results from in vivo studies are rarely reported. Perfusion-weighted imaging (PWI) and diffusion-weighted imaging (DWI) have been applied successfully to distinguish acute cerebral ischemic necrosis and penumbra in living animals; therefore, we hypothesized that PWI and DWI could be used to provide imaging evidence in vivo for the conclusion that EPO could reduce apoptosis in brain areas injured by cerebral ischemia/reperfusion. To validate this hypothesis, we established a rat model of focal cerebral ischemia/ reperfusion injury, and treated with intra-cerebroventricular injection of EPO (5,000 U/kg) 20 minutes before injury. Brain tissue in the ischemic injury zone was sampled using MRI-guided localization. The relative area of abnormal tissue, changes in PWI and DWI in the ischemic injury zone, and the number of apoptotic cells based on TdT-mediated dUTP-biotin nick end-labeling (TUNEL) were assessed. Our findings demonstrate that EPO reduces the relative area of abnormally high signal in PWI and DWI, increases cerebral blood volume, and decreases the number of apoptotic cells positive for TUNEL in the area injured by cerebral ischemia/reperfusion. The experiment pro- vides imaging evidence in vivo for EPO treating cerebral ischemia/reperfusion injury. 展开更多
关键词 nerve regeneration nerve protection cerebral ischemia/reperfusion ERYTHROPOIETIN magnetic resonance imaging diffusion-weightedimaging apparent diffusion coefficient perfusion-weighted imaging cerebral blood volume mean transit time APOPTOSIS neural regeneration
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Advanced magnetic resonance imaging findings in salivary gland tumors 被引量:3
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作者 Erkan Gökçe Murat Beyhan 《World Journal of Radiology》 2022年第8期256-271,共16页
Salivary gland tumors(SGTs)make up a small portion(approximately 5%)of all head and neck tumors.Most of them are located in the parotid glands,while they are less frequently located in the submandibular glands,minor s... Salivary gland tumors(SGTs)make up a small portion(approximately 5%)of all head and neck tumors.Most of them are located in the parotid glands,while they are less frequently located in the submandibular glands,minor salivary glands or sublingual gland.The incidence of malignant or benign tumors(BTs)in the salivary glands varies according to the salivary gland from which they originate.While most of those detected in the parotid gland tend to be benign,the incidence of malignancy increases in other glands.The use of magnetic resonance imaging(MRI)in the diagnosis of SGTs is increasing every day.While conventional sequences provide sufficient data on the presence,localization,extent and number of the tumor,they are insufficient for tumor specification.With the widespread use of advanced techniques such as diffusion-weighted imaging,semiquantitative and quantitative perfusion MRI,studies and data have been published on the differentiation of malignant or BTs and the specificity of their subtypes.With diffusion MRI,differentiation can be made by utilizing the cellularity and microstructural properties of tumors.For example,SGTs such as high cellular Warthin’s tumor(WT)or lymphoma on diffusion MRI have been reported to have significantly lower apparent diffusion values than other tumors.Contrast agent uptake and wash-out levels of tumors can be detected with semiquantitative perfusion MRI.For example,it is reported that almost all of the pleomorphic adenomas show an increasing enhancement time intensity curve and do not wash-out.On quantitative perfusion MRI studies using perfusion parameters such as Ktrans,Kep,and Ve,it is reported that WTs can show higher Kep and lower Ve values than other tumors.In this study,the contribution of advanced MRI to the diagnosis and differential diagnosis of SGTs will be reviewed. 展开更多
关键词 Salivary gland tumors Magnetic resonance imaging Diffusion-weighted imaging Dynamic contrast-enhanced imaging perfusion-weighted magnetic resonance imaging
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Value of magnetic resonance diffusion combined with perfusion imaging techniques for diagnosing potentially malignant breast lesions
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作者 Hui Zhang Xin-Yi Zhang Yong Wang 《World Journal of Clinical Cases》 SCIE 2022年第18期6021-6031,共11页
BACKGROUND Lesions of breast imaging reporting and data system(BI-RADS)4 at mammography vary from benign to malignant,leading to difficulties for clinicians to distinguish between them.The specificity of magnetic reso... BACKGROUND Lesions of breast imaging reporting and data system(BI-RADS)4 at mammography vary from benign to malignant,leading to difficulties for clinicians to distinguish between them.The specificity of magnetic resonance imaging(MRI)in detecting breast is relatively low,leading to many false-positive results and high rates of re-examination or biopsy.Diffusion-weighted imaging(DWI),combined with perfusion-weighted imaging(PWI),might help to distinguish between benign and malignant BI-RADS 4 breast lesions at mammography.AIM To evaluate the value of DWI and PWI in diagnosing BI-RADS 4 breast lesions.METHODS This is a retrospective study which included patients who underwent breast MRI between May 2017 and May 2019 in the hospital.The lesions were divided into benign and malignant groups according to the classification of histopathological results.The diagnostic efficacy of DWI and PWI were analyzed respectively and combinedly.The 95 lesions were divided according to histopathological diagnosis,with 46 benign and 49 malignant.The main statistical methods used included the Student t-test,the Mann-Whitney U-test,the chi-square test or Fisher’s exact test.RESULTS The mean apparent diffusion coefficient(ADC)values in the parenchyma and lesion area of the normal mammary gland were 1.82±0.22×10^(-3)mm^(2)/s and 1.24±0.16×10^(-3)mm^(2)/s,respectively(P=0.021).The mean ADC value of the malignant group was 1.09±0.23×10^(-3)mm^(2)/s,which was lower than that of the benign group(1.42±0.68×10^(-3)mm^(2)/s)(P=0.016).The volume transfer constant(Ktrans)and rate constant(Kep)values were higher in malignant lesions than in benign ones(all P<0.001),but there were no significant statistical differences regarding volume fraction(V_(e))(P=0.866).The sensitivity and specificity of PWI combined with DWI(91.7%and 89.3%,respectively)were higher than that of PWI or DWI alone.The accuracy of PWI combined with DWI in predicting pathological results was significantly higher than that predicted by PWI or DWI alone.CONCLUSION DWI,combined with PWI,might possibly distinguish between benign and malignant BI-RADS 4 breast lesions at mammography. 展开更多
关键词 Magnetic resonance imaging Breast diseases Diffusion-weighted imaging perfusion-weighted imaging
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急性脑缺血及再灌注的DWI与PWI实验研究 被引量:16
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作者 魏梦绮 宦怡 +5 位作者 赵海涛 韩月东 张劲松 葛雅丽 徐俊卿 杜渭清 《中国CT和MRI杂志》 2003年第1期23-26,共4页
目的利用DWI及PWI研究大鼠(MCAO)急性脑缺血再灌注模型,观察脑缺血再灌注的动态变化规律,探讨急性脑缺血的发病机理。方法建立大鼠急性脑缺血再灌注模型,45只雄性SD大鼠(280~320g),随机分成3组(A、B、C组,n=15)。单丝尼龙线置入颈内动... 目的利用DWI及PWI研究大鼠(MCAO)急性脑缺血再灌注模型,观察脑缺血再灌注的动态变化规律,探讨急性脑缺血的发病机理。方法建立大鼠急性脑缺血再灌注模型,45只雄性SD大鼠(280~320g),随机分成3组(A、B、C组,n=15)。单丝尼龙线置入颈内动脉,阻闭右侧大脑中动脉。分别于阻闭30min、1h、2h后抽出尼龙线,恢复再灌注。于再通前,再通后1h、2h、3h、6h、12h及24h行功能及常规磁共振扫描。对3组结果进行比较分析。结果(1)A组再通后较再通前DWI所示高信号区明显缩小,B组再通后较再通前不同程度缩小,C组再通后均较前略有扩大。3组间差异显著(P<0.01)。(2)急性期病灶中心血流灌注减少程度A与C组间差异有统计学意义(P<0.05)。结论DWI及PWI对于急性脑缺血及缺血再灌注后缺血灶的动态变化、发病机理、尤其是判定缺血半暗带的存在具有一定的价值。 展开更多
关键词 DWI pwi 急性脑缺血 磁共振成像 功能磁共振成像
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DSC-PWI及ASL成像联合DWI成像在诊断早期脑梗死缺血半暗带中的意义 被引量:14
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作者 邢威 黄婷婷 《中国CT和MRI杂志》 2022年第7期1-3,共3页
目的 探讨动态磁敏感对比增强-磁共振灌注成像(DSC-PWI)及动脉自旋标记成像(arterial spin labeling,ASL)成像联合DWI成像在预测早期急性脑梗死缺血半暗带(IP)中的意义,指导临床进行早期病情评估,早期治疗及选择合适治疗方案,挽救IP,改... 目的 探讨动态磁敏感对比增强-磁共振灌注成像(DSC-PWI)及动脉自旋标记成像(arterial spin labeling,ASL)成像联合DWI成像在预测早期急性脑梗死缺血半暗带(IP)中的意义,指导临床进行早期病情评估,早期治疗及选择合适治疗方案,挽救IP,改善患者的预后及生活质量,指导临床治疗。方法 选取2019年1月至2020年1月在河南中医药大学第一附属医院脑病医院收治的80例急性缺血性脑梗死患者为研究对象,均行MRI常规扫描,DWI, ASL,DSC-PWI扫描,对比患者在两种检测方式下的一般影像学指标,探讨DSC-PWI及ASL成像联合DWI成像在诊断早期脑梗死IP中的价值。结果 ASL+DWI结果显示:80例患者均表现出不同程度的高信号病死灶,且其中70例患者灌注情况一致,10例患者在DSC-PWI+DWI和ASL+DWI图示中均显示病灶存在不同灌注情况(K=0.875);80例患者中经检查发现包含110个梗死灶,且33例患者存在缺血半暗带,对比分析发现,梗死核心区与对侧镜像区DSC-PWI-CBF、ASL-CBF有显著差异(P<0.05),缺血半暗带区与对侧镜像区DSC-PWI-CBF、ASL-CBF有显著差异(P<0.05),DSC-PWI-r CBF与ASL-r CBF比较差异无统计学意义(P>0.05)。结论 ASL与DSC-PWI在急性脑梗死患者IP、血流灌注方面一致性较好,且ASL有望代替DSC-PWI应用在急性脑梗死患者IP筛查中,为临床治疗提供科学、有效的依据。 展开更多
关键词 DSC-pwi ASL成像 DWI成像 早期脑梗死 缺血半暗带
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灌注加权成像预测成人胶质瘤预后的生物学基础
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作者 郭语 郑惠敏 刘献志 《河南外科学杂志》 2024年第3期1-7,共7页
目的探讨动态敏感性对比灌注加权成像(DSC-PWI)在预测成人弥漫性胶质瘤预后中的价值及背后的生物学意义。方法选取2013-06—2021-07郑州大学第一附属医院神经外科收治并经病理检查结果确诊的343例成人型弥漫性胶质瘤患者。收集患者术前... 目的探讨动态敏感性对比灌注加权成像(DSC-PWI)在预测成人弥漫性胶质瘤预后中的价值及背后的生物学意义。方法选取2013-06—2021-07郑州大学第一附属医院神经外科收治并经病理检查结果确诊的343例成人型弥漫性胶质瘤患者。收集患者术前PWI影像数据及肿瘤标本,随机分为训练集(175例)和测试集(168例)。从PWI影像中提取影像组学特征,经筛选后建立定性的影像学预测模型。基于影像学特征及RNA-seq基因组学分析,通过基因探针富集分析(GSEA)分析和加权基因共表达网络分析(WGCNA)统合识别生物学通路。结果筛选出7个影像组学特征,计算出相应的评分,证明是预测胶质瘤预后的因素(P<0.05)。同时发现了缺氧诱导、免疫调节及肿瘤增殖三种与影像临床复合模型明显相关的生物学通路类别。结论本研究将基于机器学习的方法构建了一种新型联合模型,对胶质瘤展示出较好的预测性能。再结合RNA-seq数据找到了与胶质瘤有关的三种生物学通路。 展开更多
关键词 胶质瘤 机器学习 影像基因组学 pwi RNA-SEQ GSEA WGCNA
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rCBV在T2^*-PWI鉴别脑胶质瘤复发与放射性坏死中的价值 被引量:1
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作者 余正贤 朱斌 +1 位作者 张鑫 张冰 《浙江临床医学》 2014年第10期1534-1536,共3页
目的:探讨rCBV在T2^*-PWI脑胶质瘤复发与放射性坏死鉴别诊断中的应用价值。方法15例放射性坏死、9例脑胶质瘤复发患者在3.0T磁共振仪作传统平扫及增强的基础上行T2^*-PWI,后处理在Philips EWS工作站完成。分别以病灶强化区、水肿区... 目的:探讨rCBV在T2^*-PWI脑胶质瘤复发与放射性坏死鉴别诊断中的应用价值。方法15例放射性坏死、9例脑胶质瘤复发患者在3.0T磁共振仪作传统平扫及增强的基础上行T2^*-PWI,后处理在Philips EWS工作站完成。分别以病灶强化区、水肿区及正常对照区为感兴趣区,得到nrCBV值,以独立样本t检验比较脑胶质瘤复发及放射性坏死病灶的强化区、水肿区nrCBV值的差异。结果脑胶质瘤复发病灶的强化区与水肿区nrCBV值均高于放射性坏死区。脑胶质瘤复发病灶的强化区与水肿区nrCBV值分别为(3.27±2.32)和(1.17±0.56),放射性坏死病灶的强化区与水肿区nrCBV值分别为(0.97±0.57)和(0.58±0.22),强化区nrCBV值的诊断敏感性及特异性分别为88.2%和97.4%,而水肿区为92.3%和100%。结论脑胶质瘤复发病灶的强化区与水肿区nrCBV值均高于放射性坏死,利用T2^*-灌注加权成像可以提高脑胶质瘤复发与放射性坏死的鉴别诊断正确率。 展开更多
关键词 胶质瘤 放射性坏死 肿瘤复发
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PWI指导最后正常时间>4.5 h醒后脑卒中静脉溶栓临床观察 被引量:2
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作者 吕娟 赵红梅 +1 位作者 赵杰 王润青 《中国实用神经疾病杂志》 2018年第22期2456-2462,共7页
目的探讨磁共振灌注成像(PWI)指导最后正常时间>4. 5 h醒后脑卒中静脉溶栓的安全性及有效性。方法选取最后正常时间>4. 5 h醒后脑卒中患者,经患者或家属签署知情同意书后行磁共振检查,对存在缺血半暗带且同意静脉溶栓治疗的36例... 目的探讨磁共振灌注成像(PWI)指导最后正常时间>4. 5 h醒后脑卒中静脉溶栓的安全性及有效性。方法选取最后正常时间>4. 5 h醒后脑卒中患者,经患者或家属签署知情同意书后行磁共振检查,对存在缺血半暗带且同意静脉溶栓治疗的36例患者给予重组组织型纤溶酶原激活剂(rt-PA)静脉溶栓治疗(WUS组);同时将发病时间<4. 5 h的36例急性脑梗死患者作为溶栓对照组。记录溶栓前、溶栓后2 h、24 h、7 d、出院前NIHSS评分及溶栓后3个月mRS评分并进行比较,复查头颅CT,监测并发症。结果 2组溶栓后各时间段NIHSS评分均呈下降趋势,WUS组溶栓后各时间段NIHSS评分与治疗前相比均有明显改善(P<0. 05),而对照组NIHSS评分于溶栓后7 d、出院前明显降低(P<0. 05)。2组溶栓后3个月mRS评分(0~2)比较差异无统计学意义(P>0. 05)。2组溶栓后不良事件发生情况比较差异无统计学意义(P>0. 05)。结论对于发病时间>4. 5 h的醒后脑卒中患者,磁共振灌注成像检查指导静脉溶栓治疗安全有效。 展开更多
关键词 醒后脑卒中 急性缺血性脑卒中 磁共振灌注成像 静脉溶栓 重组组织型纤溶酶原激活剂 缺血半暗带
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功能性磁共振成像联合灌注成像定量参数评估急性脑梗死溶栓后血管再通的应用价值
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作者 韦章林 赵静 《中国急救复苏与灾害医学杂志》 2024年第9期1197-1201,共5页
目的探究功能性磁共振成像(fMRI)联合磁共振灌注成像(PWI)定量参数评估急性脑梗死(ACI)溶栓后血管再通的应用价值。方法回顾性随机选取颍上县人民医院在2020年5月—2023年5月收治的85例行溶栓治疗的急性脑梗死患者纳入研究。患者溶栓治... 目的探究功能性磁共振成像(fMRI)联合磁共振灌注成像(PWI)定量参数评估急性脑梗死(ACI)溶栓后血管再通的应用价值。方法回顾性随机选取颍上县人民医院在2020年5月—2023年5月收治的85例行溶栓治疗的急性脑梗死患者纳入研究。患者溶栓治疗前均进行fMRI和PWI检查,溶栓治疗后观察患者血管再通情况;将血管未再通患者纳入未再通组,血管再通患者纳入再通组。比较两组患者临床相关资料及fMRI、PWI参数。多因素分析影响患者溶栓治疗后血管再通的相关因素,用受试者工作特征(ROC)曲线分析fMRI联合PWI对ACI患者溶栓后血管再通的评估价值。结果ACI患者溶栓后血管再通率为65.88%(56/85)。两组速率常数相对值(rKep)、血浆容积相对值(rVp)、容量转移常数相对值(rKtrans)、性别、体质量指数(BMI)、合并基础疾病、吸烟、饮酒、梗死部位比较无统计学差异(P>0.05);再通组患者平均通过时间(MTT)、达峰时间(TTP)、年龄≥60岁患者占比、美国国立卫生研究院卒中量表(NIHSS)评分、发病至溶栓时间低于未再通组,表观扩散系数(ADC)、脑血流量(CBF)、脑血容量(CBV)高于未再通组(P<0.05)。经二元Logistic回归法分析结果显示,MTT(OR=3.487)、TTP(OR=5.421)是ACI患者溶栓后血管再通的独立危险因素,ADC(OR=0.268)、CBF(OR=0.313)是独立保护因素(P<0.05)。ROC曲线结果显示,MTT、ADC、CBF、TTP及其联合预测ACI患者溶栓后血管再通的敏感度分别为73.80%、72.10%、75.40%、77.00%、83.60%,特异性分别为75.00%、70.80%、79.20%、75.00%、91.70%,曲线下面积(AUC)分别为0.768、0.807、0.781、0.796、0.936(P<0.05)。结论MTT、TTP是影响ACI患者溶栓后再通的独立危险因素,ADC、CBF是独立保护因素,fMRI和PWI联合检查可有效预测患者溶栓后血管再通情况。 展开更多
关键词 急性脑梗死 静脉溶栓治疗 血管再通 功能性磁共振成像技术 CT灌注成像技术
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3D-pCASL评估单侧大脑中动脉慢性重度狭窄患者脑血流动力学可行性研究
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作者 代斌 刘远成 田冲 《中国CT和MRI杂志》 2024年第3期22-24,共3页
目的 探讨3D-pCASL评估单侧大脑中动脉重度狭窄患者脑血流动力学改变的可行性。方法收集CTA或M R A检查提示一侧大脑中动脉重度狭窄(血管腔狭窄70%-99%)患者32例,分别行3D-pCASL(PLD选择1.5s、2.5s)及DSC-PWI检查;在患侧DSC-达峰时间(T... 目的 探讨3D-pCASL评估单侧大脑中动脉重度狭窄患者脑血流动力学改变的可行性。方法收集CTA或M R A检查提示一侧大脑中动脉重度狭窄(血管腔狭窄70%-99%)患者32例,分别行3D-pCASL(PLD选择1.5s、2.5s)及DSC-PWI检查;在患侧DSC-达峰时间(TTP)异常最显著层面及镜面对照区分别测量两个PLD脑血流量(CBF)及DSC-PWI的CBF、脑血容量(CBV)、平均通过时间(MTT)和TTP,采用配对t检验比较两侧脑区各参数的差异。计算血管狭窄侧与镜面对照脑区相对值,采用Pearson相关检验分析各参数间相关性。同时测量AS L-PLD 1.5s CBF和DSC-TTP灌注异常区域的面积并行配对t检验。结果与对照脑区比较,32例患者异常灌注脑区ASL-PLD 1.5s及2.5s CBF、DSC-CBF、 DSC-MTT、DSC-TTP参数值间差异具有统计学意义(t值分别为-29.94、-20.07、-11.83、14.33、13.48,P值均<0.01);DSC-CBV间无统计学意义(t=-1.51,P=0.143);异常灌注脑区ASL-PLD 1.5s CBF与ASL-PLD 2.5s CBF间差异具有统计学意义(t=5.84,P<0.01)。标准化后ASLPLD 1.5s rCBF与DSC-rMTT、DSC-rTTP呈负相关(r值分别为-0.71、-0.79,P值均<0.01),ASL-PLD2.5s rCBF与DSC-rC BF差异无统计学意义(t=-1.85,P>0.05)。DSC-TTP与ASL-PLD 1.5s CBF灌注减低区域面积差异无统计学意义(t=1.834,P>0.05)。结论3D-pCASL(PLD 1.5s及2.5s)灌注成像可以评价单侧大脑中动脉重度狭窄患者脑血流动力学的改变情况,并且具有定量及无需注射钆对比剂的优点。 展开更多
关键词 动脉自旋标记(ASL) 标记后延迟时间(PLD) 动态磁敏感对比-灌注加权成像(DSC-pwi) 大脑中动脉狭窄 卒中
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大鼠放射性脑损伤的MRS、PWI研究 被引量:3
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作者 李响 段崇锋 +2 位作者 赵继平 苏华伟 隋庆兰 《医学影像学杂志》 2015年第7期1285-1288,1295,共5页
目的研究大鼠放射性脑损伤不同时期的MRS、PWI表现,为其早期诊断提供依据。方法将成年大鼠30只随机分为对照组和照射组,照射前均行MRI、MRS及PWI检查。照射组分别于照射后1、3、6、9及12个月行MRI、MRS及PWI检查,计算NAA/Cr和Cho/Cr比值... 目的研究大鼠放射性脑损伤不同时期的MRS、PWI表现,为其早期诊断提供依据。方法将成年大鼠30只随机分为对照组和照射组,照射前均行MRI、MRS及PWI检查。照射组分别于照射后1、3、6、9及12个月行MRI、MRS及PWI检查,计算NAA/Cr和Cho/Cr比值,测量灌注后大鼠双侧侧脑室周围的rCBV值。结果 1各照射组大鼠的NAA/Cr比值与对照组相比逐渐下降,差异均有统计学意义(P<0.05);照射后Cho/Cr比值先上升,3个月时达峰值,随后逐渐下降,6个月内各组的Cho/Cr与对照组相比有统计学意义(P<0.05);2照射1个月后各组的rCBV值均明显低于对照组,差异有统计学意义(P<0.05)。结论 MRS及PWI能在放射性脑损伤发生形态学改变之前检测出脑组织代谢及灌注异常,为放射性脑损伤的早期诊断提供依据。 展开更多
关键词 放射性脑损伤 磁共振波谱成像 磁共振灌注成像
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Role of MR-DWI and MR-PWI in the radiotherapy of implanted pulmonary VX-2 carcinoma in rabbits 被引量:5
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作者 Qiang Zhang Mingmin Zhang +6 位作者 Zhaoxin Liu Baoqi Shi Fuliang Qi Haijiang Wang Yuan Lv Haijiao Jin Weijing Zhang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2014年第5期532-542,共11页
Objective: To detect the activity of tumor cells and tumor blood flow before and after the radiotherapy of implanted pulmonary VX-2 carcinoma in rabbit models by using magnetic resonance diffusion-weighted imaging(M... Objective: To detect the activity of tumor cells and tumor blood flow before and after the radiotherapy of implanted pulmonary VX-2 carcinoma in rabbit models by using magnetic resonance diffusion-weighted imaging(MR-DWI) and magnetic resonance perfusion weighted imaging(MR-PWI), and to evaluate the effectiveness and safety of the radiotherapy based on the changes in the MR-DWI and MR-PWI parameters at different treatment stages.Methods: A total of 56 rabbit models with implanted pulmonary VX-2 carcinoma were established, and then equally divided into treatment group and control group. MR-DWI and MR-PWI were separately performed using a Philips Acheiva 1.5T MRI machine(Philips, Netherland). MRI image processing was performed using special perfusion software and the WORKSPACE advanced workstation for MRI. MRDWI was applied for the observation of tumor signals and the measurement of apparent diffusion coefficient(ADC) values; whereas MR-PWI was used for the measurement of wash in rate(WIR), wash out rate(WOR), and maximum enhancement rate(MER). The radiation treatment was performed using Siemens PRIMUS linear accelerator. In the treatment group, the radiotherapy was performed 21 days later on a once weekly dosage of 1,000 c Gy to yield a total dosage of 5,000 c Gy.Results: The ADC parameters in the region of interest on DWI were as follows: on the treatment day for the implanted pulmonary VX-2 carcinoma, the t values at the center and the edge of the lesions were 1.352 and 1.461 in the treatment group and control group(P〉0.05). During weeks 0-1 after treatment, the t values at the center and the edge of the lesions were 1.336 and 1.137(P〉0.05). During weeks 1-2, the t values were 1.731 and 1.736(P〈0.05). During weeks 2-3, the t values were 1.742 and 1.749(P〈0.05). During weeks 3-4, the t values were 2.050 and 2.127(P〈0.05). During weeks 4-5, the t values were 2.764 and 2.985(P〈0.05). The ADC values in the treatment group were significantly higher than in the control group. After the radiotherapy(5,000 c Gy), the tumors remarkably shrank, along with low signal on DWI, decreased signal on ADC map, and remarkably increased ADC values. As shown on PWI, on the treatment day for the implanted pulmonary VX-2 carcinoma, the t values of the WIR, WOR, and MER at the center of the lesions were 1.05, 1.31, and 1.33 in the treatment group and control group(P〉0.05); in addition, the t values of the WIR, WOR, and MER at the edge of the lesions were 1.35, 1.07, and 1.51(P〉0.05). During weeks 0-1 after treatment, the t values of the WIR, WOR, and MER at the center of the lesions were 1.821, 1.856, and 1.931(P〈0.05); in addition, the t values of the WIR, WOR, and MER at the edge of the lesions were 1.799, 2.016, and 2.137(P〈0.05). During weeks 1-1 after treatment, the t values of the WIR, WOR, and MER at the center of the lesions were 2.574, 2.156, and 2.059(P〈0.05) and the t values of the WIR, WOR, and MER at the edge of the lesions were 1.869, 2.058, and 2.057(P〈0.05). During weeks 2-3 after treatment, the t values of the WIR, WOR, and MER at the center of the lesions were 2.461, 2.098, and 2.739(P〈0.05) and the t values of the WIR, WOR, and MER at the edge of the lesions were 2.951, 2.625, and 2.154(P〈0.05). During weeks 3-4 after treatment, the t values of the WIR, WOR, and MER at the center of the lesions were 2.584, 2.107, and 2.869(P〈0.05) and the t values of the WIR, WOR, and MER at the edge of the lesions were 2.057, 2.637, and 2.951(P〈0.05). During weeks 4-5 after treatment, the t values of the WIR, WOR, and MER at the center of the lesions were 2.894, 2.827, and 3.285(P〈0.05) and the t values of the WIR, WOR, andMER at the edge of the lesions were 3.45, 3.246, and 3.614(P〈0.05). After the radiotherapy(500 c Gy), the tumors shrank on the T1 WI, WIR, WOR, and MER; meanwhile, the PWI parameter gradually decreased and reached its minimum value.Conclusions: MR-DWI and MR-PWI can accurately and directly reflect the inactivation of tumor cells and the tumor hemodynamics in rabbit models with implanted pulmonary VX-2 carcinoma, and thus provide theoretical evidences for judging the clinical effectiveness of radiotherapy for the squamous cell carcinoma of the lung. 展开更多
关键词 Magnetic resonance diffusion-weighted imaging(MR-DWI) magnetic resonance perfusion weighted imaging(MR-pwi implanted pulmonary VX-2 carcinoma in rabbits RADIOTHERAPY
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1.5TMRI扫描PWI成像评估脑星形细胞瘤WHO分级诊断的效果
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作者 李辉 蔡定萍 姚俊 《海南医学》 CAS 2022年第24期3225-3228,共4页
目的 分析1.5T核磁共振成像(MRI)扫描灌注加权(PWI)成像评估脑星形细胞瘤WHO分级诊断的效果。方法 选取2019年3月至2022年1月安康市中心医院收治且经手术病理确诊的125例脑星形细胞瘤为研究对象,根据组织病理分级,其中低级别组(WHOⅠ~Ⅱ... 目的 分析1.5T核磁共振成像(MRI)扫描灌注加权(PWI)成像评估脑星形细胞瘤WHO分级诊断的效果。方法 选取2019年3月至2022年1月安康市中心医院收治且经手术病理确诊的125例脑星形细胞瘤为研究对象,根据组织病理分级,其中低级别组(WHOⅠ~Ⅱ级) 61例,高级别组(WHOⅢ~Ⅳ级) 64例。比较不同级别星形细胞瘤的血流灌注参数变化;采用Pearson相关评估相对脑血容量(rCBV)值、相对脑血流量(rCBF)值、相对平均通过时间(rMTT)与病理分级相关性;以手术病理结果为金标准,应用准确度、灵敏度、特异度、阳性预测值及阴性预测值分析灌注参数的诊断价值。结果 高级别组患者的rCBV、rCBF分别为4.26±2.17、2.34±1.34,明显高于低级别组的1.42±0.38、1.23±0.26,差异均有统计学意义(P<0.05),但两组患者的r MTT比较差异无统计学意义(P>0.05);经Pearson相关分析结果显示,rCBV、rCBF与病理分级呈正相关(r=0.426、0.563,P<0.05),而rMTT与病理分级无相关性(r=0.006,P>0.05);以手术病理结果为金标准,MRI平扫+增强对高、低级别星形细胞瘤分级诊断准确度为65.23%、灵敏性为68.33%、特异性为63.27%,PWI成像中rCBV准确度为83.96%,阳性预测值为91.56%;rCBF准确度为81.73%,阳性预测值为90.43%;rMTT准确度为77.53%,阳性预测值为88.26%。结论 MRI扫描PWI成像对脑星形细胞瘤WHO分级诊断效果良好,对于后续治疗和预后指导具有重要价值。 展开更多
关键词 1.5T核磁共振成像 灌注加权成像 脑星形细胞瘤 WHO分级 诊断价值
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基于子母共位电磁超声换能器的平面波成像 被引量:1
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作者 王星宇 郑阳 +2 位作者 周进节 张宗健 张吉堂 《传感器与微系统》 CSCD 北大核心 2023年第11期23-26,30,共5页
为了实现电磁超声相控阵单通道激励下的平面波成像(PWI),提升检测效率,设计了一种新型电磁超声相控阵换能器,命名为子母共位电磁超声换能器(EMAT)。该换能器将激发线圈与接收线圈分离,激发线圈为整体线圈,接收线圈为分离多通道线圈,两... 为了实现电磁超声相控阵单通道激励下的平面波成像(PWI),提升检测效率,设计了一种新型电磁超声相控阵换能器,命名为子母共位电磁超声换能器(EMAT)。该换能器将激发线圈与接收线圈分离,激发线圈为整体线圈,接收线圈为分离多通道线圈,两类线圈共用一组磁体。该换能器可降低实验仪器操作复杂性,使得不需要相控阵全通道激发,采用单通道激励即可以实现电磁超声平面波成像。本文使用子母共位电磁超声换能器对“斜向排列”的2 mm直径阶梯横通孔缺陷进行成像检测,结果表明:常规平面波算法检测的纵向定位误差在0.5 mm范围内,横向定位误差在2 mm范围内,采用相位相干算法可辅助提升成像信噪比(SNR),表明该类型换能器对于平面波成像快速检测是适用的。 展开更多
关键词 电磁超声换能器 无损检测 平面波成像 缺陷识别
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磁共振多技术联合应用对诊断原发性脑内恶性淋巴瘤的价值 被引量:3
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作者 王自勇 胡永胜 +2 位作者 何新华 巢惠民 王劲武 《中国医学计算机成像杂志》 CSCD 北大核心 2012年第4期289-293,共5页
目的:探讨常规MRI扫描通过结合DWI、PWI、TDC、MRS多项技术联合应用对原发性脑内恶性淋巴瘤的诊断价值。方法:回顾性分析29例经临床病理证实的原发性脑内恶性淋巴瘤病例,其治疗前常规MRI信号特点与DWI、PWI、TDC和MRS的表现。结果:原发... 目的:探讨常规MRI扫描通过结合DWI、PWI、TDC、MRS多项技术联合应用对原发性脑内恶性淋巴瘤的诊断价值。方法:回顾性分析29例经临床病理证实的原发性脑内恶性淋巴瘤病例,其治疗前常规MRI信号特点与DWI、PWI、TDC和MRS的表现。结果:原发性脑内恶性淋巴瘤T_1WI呈等或稍低信号,T_2WI呈稍高信号,灶周中度水肿,增强后大多呈均匀强化,顶叶病灶可见"压迹征",病变累及胼胝体时呈"蝴蝶征";DWI多呈均匀高信号,ADC值与对侧正常脑实质相比明显降低;PWI示rCBV呈等或等低灌注,与正常脑白质灌注相似,多呈黄绿或蓝色;TDC负性增强上升支与下降支基本对称,信号强度回复前出现一小的再下降波形,增强后基线水平较增强前基线水平呈缓慢上升;MRS示Cho峰明显升高,病灶内NAA中度、Cr峰轻度降低,可见Lip峰、Cho/Cr、Lip/Cr、Lac/Cr均明显升高,NAA/Cr明显降低。结论:原发性脑内恶性淋巴瘤常规MRI具有一定特征性,通过联合应用DWI、ADC、PWI、TDC和MRS表现可提高对其诊断水平。 展开更多
关键词 淋巴瘤 磁共振成像 弥散加权成像 灌注加权成像 磁共振波谱
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磁共振灌注成像在胰腺癌中的应用现状研究 被引量:10
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作者 杨淑芳 张和平 +1 位作者 王长福 王斌杰 《中国CT和MRI杂志》 2012年第5期106-109,共4页
磁共振灌注加权成像是近年来随着磁共振快速成像序列的出现而发展起来的一项功能成像技术,能够直观的反映组织、器官的血流动力学和微循环灌注情况,是影像学从形态学到功能学发展的一种体现。胰腺癌是胰腺最常见的恶性肿瘤,其临床诊断... 磁共振灌注加权成像是近年来随着磁共振快速成像序列的出现而发展起来的一项功能成像技术,能够直观的反映组织、器官的血流动力学和微循环灌注情况,是影像学从形态学到功能学发展的一种体现。胰腺癌是胰腺最常见的恶性肿瘤,其临床诊断及疗效评估主要依靠影像学检查方法。本文综述了MR灌注成像的原理、意义及其在胰腺癌的术前诊断、鉴别诊断及临床治疗中的应用现状。 展开更多
关键词 磁共振成像 灌注加权成像 胰腺癌
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