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Magnetic resonance imaging techniques for lithium-ion batteries:Principles and applications
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作者 Hongxin Lin Yanting Jin +4 位作者 Mingming Tao Yingao Zhou Peizhao Shan Danhui Zhao Yong Yang 《Magnetic Resonance Letters》 2024年第2期22-39,共18页
Operando monitoring of internal and local electrochemical processes within lithium-ion batteries(LIBs)is crucial,necessitating a range of non-invasive,real-time imaging characterization techniques including nuclear ma... Operando monitoring of internal and local electrochemical processes within lithium-ion batteries(LIBs)is crucial,necessitating a range of non-invasive,real-time imaging characterization techniques including nuclear magnetic resonance(NMR)techniques.This review provides a comprehensive overview of the recent applications and advancements of non-invasive magnetic resonance imaging(MRI)techniques in LIBs.It initially introduces the principles and hardware of MRI,followed by a detailed summary and comparison of MRI techniques used for characterizing liquid/solid electrolytes,electrodes and commercial batteries.This encompasses the determination of electrolytes'transport properties,acquisition of ion distribution profile,and diagnosis of battery defects.By focusing on experimental parameters and optimization strategies,our goal is to explore MRI methods suitable to a variety of research subjects,aiming to enhance imaging quality across diverse scenarios and offer critical physical/chemical insights into the ongoing operation processes of LIBs. 展开更多
关键词 Lithium-ion batteries magnetic resonance imaging(mri) Electrolytes ELECTRODES Commercial batteries
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Reduced Imaging Time and Improved Image Quality of 3D Isotropic T2-Weighted Magnetic Resonance Imaging with Compressed Sensing for the Female Pelvis
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作者 Hao Mei Feng Xiao Ming Deng 《Journal of Beijing Institute of Technology》 EI CAS 2023年第5期579-585,共7页
This study is to compare three-dimensional(3D)isotropic T2-weighted magnetic resonance imaging(MRI)with compressed sensing-sampling perfection with application optimized contrast(CS-SPACE)and the conventional image(3D... This study is to compare three-dimensional(3D)isotropic T2-weighted magnetic resonance imaging(MRI)with compressed sensing-sampling perfection with application optimized contrast(CS-SPACE)and the conventional image(3D-SPACE)sequence in terms of image quality,estimated signal-to-noise ratio(SNR),relative contrast-to-noise ratio(CNR),and the lesions’conspicuous of the female pelvis.Thirty-six females(age:51,28-73)with cervical carcinoma(n=20),rectal carcinoma(n=7),or uterine fibroid(n=9)were included.Patients underwent magnetic resonance(MR)imaging at a 3T scanner with the sequences of 3D-SPACE,CS-SPACE,and twodimensional(2D)T2-weighted turbo-spin echo(TSE).Quantitative analyses of estimated SNR and relative CNR between tumors and other tissues,image quality,and tissue conspicuity were performed.Two radiologists assessed the difference in diagnostic findings for carcinoma.Quantitative values and qualitative scores were analyzed,respectively.The estimated SNR and the relative CNR of tumor-to-muscle obturator internus,tumor-to-myometrium,and myometrium-to-muscle obturator internus was comparable between 3D-SPACE and CS-SPACE.The overall image quality and the conspicuity of the lesion scores of the CS-SPACE were higher than that of the 3D-SPACE(P<0.01).The CS-SPACE sequence offers shorter scan time,fewer artifacts,and comparable SNR and CNR to conventional 3D-SPACE,and has the potential to improve the performance of T2-weighted images. 展开更多
关键词 compressed sensing sampling perfection with application-oriented contrasts(SPACE)using variable flip angle evolutions three-dimensional(3D)imaging magnetic resonance imaging(mri) PELVIS
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Role of pulmonary perfusion magnetic resonance imaging for the diagnosis of pulmonary hypertension:A review
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作者 Miriam Lacharie Adriana Villa +3 位作者 Xenios Milidonis Hadeer Hasaneen Amedeo Chiribiri Giulia Benedetti 《World Journal of Radiology》 2023年第9期256-273,共18页
Among five types of pulmonary hypertension,chronic thromboembolic pulmonary hypertension(CTEPH)is the only curable form,but prompt and accurate diagnosis can be challenging.Computed tomography and nuclear medicine-bas... Among five types of pulmonary hypertension,chronic thromboembolic pulmonary hypertension(CTEPH)is the only curable form,but prompt and accurate diagnosis can be challenging.Computed tomography and nuclear medicine-based techniques are standard imaging modalities to non-invasively diagnose CTEPH,however these are limited by radiation exposure,subjective qualitative bias,and lack of cardiac functional assessment.This review aims to assess the methodology,diagnostic accuracy of pulmonary perfusion imaging in the current literature and discuss its advantages,limitations and future research scope. 展开更多
关键词 Pulmonary perfusion mri Pulmonary hypertension Dynamic contrast enhanced magnetic resonance imaging Chronic thromboembolic pulmonary hypertension Computed tomography pulmonary angiography Chronic thromboembolic disease
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Application of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)combined with magnetic resonance spectroscopy(MRS)in prostate cancer diagnosis 被引量:1
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作者 Yakun He Min Wang +1 位作者 Heping Deng Jin Ren 《Oncology and Translational Medicine》 CAS 2021年第1期31-34,共4页
Objective The aim of the study was to investigate the application of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)combined with magnetic resonance spectroscopy(MRS)in prostate cancer diagnosis.Methods ... Objective The aim of the study was to investigate the application of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)combined with magnetic resonance spectroscopy(MRS)in prostate cancer diagnosis.Methods In the outpatient department of our hospital(Sichuan Cancer Hospital,Chengdu,China),60 patients diagnosed with prostate disease were selected randomly and included in a prostate cancer group,60 patients with benign prostatic hyperplasia were included in a proliferation group,and 60 healthy subjects were included in a control group,from January 2013 to January 2017.Using Siemens Avanto 1.5 T high-field superconducting MRI for DCE-MRI and MRS scans,after the MRS scan was completed,we used the workstation spectroscopy tab spectral analysis,and eventually obtained the crest lines of the prostate metabolites choline(Cho),creatine(Cr),citrate(Cit),and the values of Cho/Cit,and(Cho+Cr)/Cit.Results Participants who had undergone 21-s,1-min,and 2-min dynamic contrast-enhanced MR revealed significant variations among the three groups.The spectral analysis of the three groups revealed a significant variation as well.DCE-MRI and MRS combined had a sensitivity of 89.67%,specificity of 95.78%,and accuracy of 94.34%.Conclusion DCE-MRI combined with MRS is of great value in the diagnosis of prostate cancer. 展开更多
关键词 prostate cancer magnetic resonance imaging(mri) dynamic contrast-enhanced(DCE) spectroscopy
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Generalized Nonconvex Low-Rank Algorithm for Magnetic Resonance Imaging (MRI) Reconstruction
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作者 吴新峰 刘且根 +2 位作者 卢红阳 龙承志 王玉皞 《Journal of Donghua University(English Edition)》 EI CAS 2017年第2期316-321,共6页
In recent years,utilizing the low-rank prior information to construct a signal from a small amount of measures has attracted much attention.In this paper,a generalized nonconvex low-rank(GNLR) algorithm for magnetic r... In recent years,utilizing the low-rank prior information to construct a signal from a small amount of measures has attracted much attention.In this paper,a generalized nonconvex low-rank(GNLR) algorithm for magnetic resonance imaging(MRI)reconstruction is proposed,which reconstructs the image from highly under-sampled k-space data.In the algorithm,the nonconvex surrogate function replacing the conventional nuclear norm is utilized to enhance the low-rank property inherent in the reconstructed image.An alternative direction multiplier method(ADMM) is applied to solving the resulting non-convex model.Extensive experimental results have demonstrated that the proposed method can consistently recover MRIs efficiently,and outperforms the current state-of-the-art approaches in terms of higher peak signal-to-noise ratio(PSNR) and lower high-frequency error norm(HFEN) values. 展开更多
关键词 magnetic resonance imaging(mri) low-rank approximation nonconvex optimization alternative direction multiplier method(ADMM)
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Obstacles Facing the Implementation of Functional Magnetic Resonance Imaging (fMRI) of Brain in Jeddah City
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作者 Abrar Mohammed Shafia M. Noor Hanan Mohammed Alzahrani Zuber Ahmed 《Computer Technology and Application》 2013年第2期123-126,共4页
fMRI (Functional Magnetic Resonance Imaging) is a relatively new technique that uses MRI (Magnetic Resonance Imaging) to measure the hemodynamic response (change in blood flow) related to neural activity in the ... fMRI (Functional Magnetic Resonance Imaging) is a relatively new technique that uses MRI (Magnetic Resonance Imaging) to measure the hemodynamic response (change in blood flow) related to neural activity in the brain. This paper aims to explore and identify the obstacles facing the implementation and applications of IMRI in radiology departments within Jeddah city by analyzing related data received by direct questionnaires and interviews with all the people working in MRI units in Jeddah city and finds that the major obstacle is lacking of awareness of fMRI among medical professionals and their training. 展开更多
关键词 fmri (Functional magnetic resonance imaging brain imaging mri magnetic resonance imaging).
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动态增强MRI定量参数及肿瘤标记物对乳腺癌新辅助化疗疗效的评估价值分析 被引量:2
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作者 马瑞 王彦辉 +3 位作者 杜敏 齐先龙 张琳 王唯伟 《中国医学装备》 2024年第1期73-77,共5页
目的:探索动态增强磁共振成像(DCE-MRI)定量参数及肿瘤标记物对乳腺癌新辅助化疗疗效的评估价值。方法:选取2019年5月至2022年5月在济宁市第一人民医院接受新辅助化疗联合手术干预的75例乳腺癌患者,根据实体瘤疗效评价标准(RECIST)将其... 目的:探索动态增强磁共振成像(DCE-MRI)定量参数及肿瘤标记物对乳腺癌新辅助化疗疗效的评估价值。方法:选取2019年5月至2022年5月在济宁市第一人民医院接受新辅助化疗联合手术干预的75例乳腺癌患者,根据实体瘤疗效评价标准(RECIST)将其分为有效组(54例)和无效组(21例),比较化疗前和化疗后两组患者DCE-MRI定量参数血管外细胞外间隙容积比(V_(e))、速率常数(K_(ep))及容积转换常数(K^(trans))指标与肿瘤标志物癌胚抗原(CEA)、糖类抗原(CA125)及糖类抗原15-3(CA15-3)水平,采用受试者工作特征(ROC)曲线分析各项诊断方式预测效能。结果:化疗后,有效组患者DCEMRI定量参数Ve、K_(ep)及K^(trans)与无效组比较,差异有统计学意义(t=7.237、51.695、16.879,P<0.05)。有效组患者肿瘤标志物CEA、CA125及CA15-3与无效组比较,差异有统计学意义(t=44.201、6.736、6.885,P<0.05)。V_(e)、K_(ep)、K^(trans)、CEA、CA125及CA15-3的6项指标联合预测乳腺癌新辅助化疗疗效ROC曲线下面积(AUC)值为0.979,显著高于各项指标单独检测的AUC值,差异有统计学意义(Z=2.993、2.679、2.510、2.731、3.215、3.071,P<0.05)。结论:肿瘤标记物联合DCE-MRI定量参数可更好预测乳腺癌新辅助化疗疗效情况,间接评估预后。 展开更多
关键词 动态增强磁共振成像(DCE-mri) 肿瘤标记物 化疗 乳腺癌
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基于多模态MRI定量分析诊断宫颈癌宫旁浸润的研究
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作者 牛俊巧 王佳 +3 位作者 刘焱 曲源 张建亮 李辉 《中国CT和MRI杂志》 2024年第5期137-139,共3页
目的探讨多模态MRI定量分析诊断宫颈癌宫旁浸润的价值。方法回顾性分析2019年1月~2021年12月新疆维吾尔自治区人民医院收治的86例宫颈癌患者临床资料,根据病理结果分为宫旁浸润组31例与非宫旁浸润组55例。所有患者均接受MRI常规平扫及... 目的探讨多模态MRI定量分析诊断宫颈癌宫旁浸润的价值。方法回顾性分析2019年1月~2021年12月新疆维吾尔自治区人民医院收治的86例宫颈癌患者临床资料,根据病理结果分为宫旁浸润组31例与非宫旁浸润组55例。所有患者均接受MRI常规平扫及扩散加权成像(DWI)扫描、动态对比增强磁共振成像(DCE-MRI)扫描,获得感兴趣区表观弥散系数(ADC)值和对比剂容积转换常量(K^(trans))、速率常数(K_(ep))、血管外细胞间隙容积分数(V_(e))值等多模态MRI定量参数。比较宫旁浸润组和非宫旁浸润组临床特征、ADC值和DCE-MRI定量参数;Pearson相关性分析宫颈癌宫旁浸润患者ADC值和K^(trans)、K_(ep)、V_(e)的关系;受试者工作特征曲线(ROC)分析ADC值和K^(trans)、K_(ep)、V_(e)对宫颈癌宫旁浸润的诊断效能。结果宫旁浸润组与非宫旁浸润组肿瘤直径和病理分级的分布差异比较,差异有统计学意义(P<0.05);宫旁浸润组K^(trans)、K_(ep)和V_(e)均明显高于非宫旁浸润组(P<0.05);Pearson相关性显示,宫颈癌宫旁浸润患者ADC值与V_(e)值呈明显的正相关(P<0.05);ROC显示,K^(trans)、K_(ep)、V_(e)值诊断宫颈癌宫旁浸润的曲线下面积(AUC)分别为0.876、0.821和0.864(P<0.05)。结论多模态MRI定量参数对宫颈癌宫旁浸润具有较好的诊断价值,可为宫颈癌宫旁浸润的影像诊断提供量化参考。 展开更多
关键词 多模态mri 扩散加权成像 动态对比增强磁共振成像 表观弥散系数 宫颈癌 宫旁浸润
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脊椎骨内神经鞘瘤的CT、MRI表现(附11例报道及文献复习)
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作者 刘玉 王远军 李开成 《生物医学工程学进展》 CAS 2024年第2期136-141,共6页
目的探讨脊椎骨内神经鞘瘤(Intraosseous Schwannoma,IOS)的特征性影像学表现,以与其他脊椎溶骨性病变区别开。方法回顾性分析上海交通大学医学院附属第九人民医院经手术病理证实的脊椎IOS的临床资料及CT、MRI等影像学资料。该文收集了1... 目的探讨脊椎骨内神经鞘瘤(Intraosseous Schwannoma,IOS)的特征性影像学表现,以与其他脊椎溶骨性病变区别开。方法回顾性分析上海交通大学医学院附属第九人民医院经手术病理证实的脊椎IOS的临床资料及CT、MRI等影像学资料。该文收集了11例脊椎IOS患者,其中男性7例,女性4例,年龄23~74岁[平均年龄(51±17)岁]。所有患者均行CT和MRI检查。由两名高年资骨关节系统放射科医师对所有影像学征象进行评估,并复习了近几年来文献报告的脊椎IOS影像学征象。结果病变累及部位包括颈椎3例(3/11,27.3%),胸椎1例(1/11,9.1%),腰椎5例(5/11,45.5%),腰骶椎2例(2/11,18.2%),最大径(5.8±2.85)cm,形态均为不规则形。CT显示偏心性膨胀性溶骨性骨质破坏,密度不均匀,平扫CT值为(43.0±11.55)HU。增强后不均匀轻度强化,CT值为(70.3±12.22)HU,病灶边界清晰,有硬化缘,未见骨膜反应,病灶易沿着椎间孔向椎管内外延伸。在MRI上,与肌肉组织相比,病灶在T1WI上呈等稍低信号,在T2WI上呈混杂稍高信号,压脂后呈混杂高信号,DWI未见弥散受限,ADC值为(1.25±0.176)×10-3mm2/s,增强后不均匀明显强化,时间-信号强度曲线为I型,7例患者病灶内发生囊性变。结论脊椎IOS是一种罕见的良性肿瘤,影像学表现具有一定的特征性,在鉴别诊断边界清晰的具有异质性的脊椎溶骨性病变时应予以考虑。 展开更多
关键词 骨内神经鞘瘤 脊椎 计算机断层扫描 核磁共振
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MRI梯度波形发生器研究进展
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作者 刘颖 林羚 +1 位作者 袁斌华 章浩伟 《波谱学杂志》 CAS 2024年第1期99-115,共17页
成像体素空间位置的准确编码对于磁共振成像(MRI)的空间定位至关重要.为了保证空间编码的准确性,获得高性能的梯度磁场是关键.梯度波形发生器是产生梯度磁场的核心部件,本文简要介绍了梯度波形发生器的工作原理和组成部分,总结了近二十... 成像体素空间位置的准确编码对于磁共振成像(MRI)的空间定位至关重要.为了保证空间编码的准确性,获得高性能的梯度磁场是关键.梯度波形发生器是产生梯度磁场的核心部件,本文简要介绍了梯度波形发生器的工作原理和组成部分,总结了近二十年来基于不同设计方案设计的梯度波形发生器的研究进展,详细探讨了梯度波形预加重的实现方法,并对梯度波形发生器未来的研究和发展方向进行了展望. 展开更多
关键词 磁共振成像 梯度波形发生器 数字信号处理器 现场可编程门阵列 预加重
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基于MRI影像组学鉴别胶质瘤及单发脑转移瘤的应用研究
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作者 王静 宗会迁 +3 位作者 张娅 宋静 徐子超 彭兴珍 《中国医疗设备》 2024年第9期94-100,共7页
目的分析基于多模态磁共振成像(Magnetic Resonance Imaging,MRI)影像组学鉴别胶质瘤及单发脑转移瘤的研究进展,得出提升鉴别准确性的要素。方法通过检索PubMed、Web of Science及FMRS外文医学信息资源检索平台3个数据库,根据纳入排除标... 目的分析基于多模态磁共振成像(Magnetic Resonance Imaging,MRI)影像组学鉴别胶质瘤及单发脑转移瘤的研究进展,得出提升鉴别准确性的要素。方法通过检索PubMed、Web of Science及FMRS外文医学信息资源检索平台3个数据库,根据纳入排除标准,对纳入的文章提取数据来源、患者数量、MRI设备、MRI序列、肿瘤分割软件、分割方式、分割范围、分割类型、特征提取方法、筛选方法、机器学习分类器、最优的机器学习分类器等数据进行综合分析。结果最终纳入12篇文献进行分析,大多数研究选择MRI传统结构序列,特征筛选方法选择最多的是最小绝对收缩和选择算子,使用最多且表现最佳的机器学习分类器为随机森林。结论MRI影像组学方法在鉴别胶质瘤及单发脑转移瘤方面展现出了较高的准确性,为临床决策提高了较大帮助。 展开更多
关键词 影像组学 磁共振成像 机器学习 胶质瘤 单发脑转移瘤
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面向急性缺血性脑卒中的CT生成MRI算法 被引量:1
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作者 张美美 秦品乐 +4 位作者 柴锐 曾建潮 翟双姣 闫俊义 冯二燕 《计算机工程》 CAS CSCD 北大核心 2024年第2期317-326,共10页
急性缺血性脑卒中病灶在计算机断层扫描(CT)上表现不明显,但在核磁共振成像(MRI)上可以清晰显示。然而,当患者体内有金属植入物等特殊情况则无法进行MRI检测,使得患者的治疗受到延误。通过CT生成MRI可在急性缺血性脑卒中的诊断和治疗中... 急性缺血性脑卒中病灶在计算机断层扫描(CT)上表现不明显,但在核磁共振成像(MRI)上可以清晰显示。然而,当患者体内有金属植入物等特殊情况则无法进行MRI检测,使得患者的治疗受到延误。通过CT生成MRI可在急性缺血性脑卒中的诊断和治疗中起到至关重要的作用,但现有的医学影像跨模态生成方法从CT得到的MRI缺乏病灶信息且边界模糊。为了解决上述问题,提出一种基于影像组学和扩散生成对抗网络的急性缺血性脑卒中CT生成MRI算法,通过影像组学在CT上进行病灶特征增强,突出生成MRI的病灶信息,引入梯度损失为生成图像与真实图像增加边缘感知约束,提升生成MRI的质量。在ISLES2018挑战赛数据集上的实验结果表明,该算法生成的MRI在整体上的峰值信噪比为23.051 dB,结构相似度为0.798,皮尔逊相关系数为0.969,并且病灶区域的互信息为2.075,与现有的生成模型相比,该算法的各项指标均达到最优。此外,经3名经验丰富的放射科医生在生成的MRI上确定病灶并进行阳性/阴性分类,其中生成的MRI中无错误病灶,且分类准确率可达到86.61%,可作为一种辅助工具协助医生进行诊断。 展开更多
关键词 医学图像生成 影像组学 扩散生成对抗网络 计算机断层扫描 核磁共振成像
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乳腺癌表型影响新辅助化疗后MRI反应评估的准确性
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作者 郭转转 张冰 +4 位作者 张莉 雷喆 梁文斌 杨全新 陈欣 《西安交通大学学报(医学版)》 CAS CSCD 北大核心 2024年第4期552-559,共8页
目的 探讨磁共振成像(MRI)评估乳腺癌新辅助化疗(neoadjuvant chemotherapy, NAC)后病理完全缓解(pathologic complete response, pCR)准确性的影响因素。方法 回顾性分析2019年7月至2021年12月于西安交通大学第二附属医院接受NAC的89... 目的 探讨磁共振成像(MRI)评估乳腺癌新辅助化疗(neoadjuvant chemotherapy, NAC)后病理完全缓解(pathologic complete response, pCR)准确性的影响因素。方法 回顾性分析2019年7月至2021年12月于西安交通大学第二附属医院接受NAC的89例乳腺癌患者,在NAC前及全程结束后分别行乳腺MRI检查。根据NAC全程结束后手术所获得的病理结果,以Miller-Payne分级为评估标准,分为pCR与非病理完全缓解(npCR)2个亚组。应用卡方检验比较两组间NAC前病变MRI特征。应用受试者工作特征(ROC)曲线分析MRI评估NAC后pCR的准确性、敏感度、特异度、阳性预测值、阴性预测值,并分析MRI预测不同肿瘤亚型pCR的诊断效能。单变量和多变量分析影响放射学完全缓解(radiographic complete response, rCR)和pCR一致性的因素。结果 NAC后MRI分析显示rCR 20例(22.5%),pCR 28例(31.5%),将rCR视为MRI分析的“阳性”结果,MRI评估正确79例,其中真阳性19例,真阴性60例,评估错误10例,其中假阴性9例,假阳性1例,MRI评估pCR的敏感度、特异度、准确性、阳性预测值、阴性预测值分别为67.86%、98.36%、88.76%、95.00%、86.96%;MRI评估ERBB2+型乳腺癌NAC后pCR的诊断效能最低。单因素分析显示,雌激素受体(ER)、临床分期、背景实质强化及肿瘤最大径均影响rCR和pCR一致性(P<0.05);多因素Logistic回归分析显示,临床分期是影响rCR和pCR一致性的独立影响因素。结论 MRI评估乳腺癌NAC后pCR整体准确性良好,治疗前MRI特征和肿瘤亚型可能与乳腺癌患者NAC治疗后MRI的诊断准确性相关。 展开更多
关键词 乳腺癌 新辅助化疗(NAC) 磁共振成像(mri) 病理完全缓解(pCR)
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Current and future applications of magnetic resonance imaging and spectroscopy of the brain in hepatic encepha-lopathy 被引量:8
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作者 VP Bob Graver M Alex Dresner +5 位作者 Daniel M Forton Serena Counsell David J Larkman Nayna Patel Howard C Thomas Simon D Taylor-Robinson 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第19期2969-2978,共10页
Hepatic encephalopathy (HE) is a common neuropsychiatric abnormality, which complicates the course of patients with liver disease and results from hepatocellular failure and/or portosystemic shunting. The manifestat... Hepatic encephalopathy (HE) is a common neuropsychiatric abnormality, which complicates the course of patients with liver disease and results from hepatocellular failure and/or portosystemic shunting. The manifestations of HE are widely variable and involve a spectrum from mild subclinical disturbance to deep coma. Research interest has focused on the role of circulating gut-derived toxins, particularly ammonia, the development of brain swelling and changes in cerebral neurotransmitter systems that lead to global CNS depression and disordered function. Until recently the direct investigation of cerebral function has been difficult in man. However, new magnetic resonance imaging (MRI) techniques provide a non-invasive means of assessment of changes in brain volume (coregistered MRI) and impaired brain function (fMRI), while proton magnetic resonance spectroscopy (^1H MRS) detects changes in brain biochemistry, including direct measurement of cerebral osmolytes, such as myoinositol, glutamate and glutamine which govern processes intrinsic to cellular homeostasis, including the accumulation of intracellular water. The concentrations of these intracellular osmolytes alter with hyperammonaemia. MRS-detected metabolite abnormalities correlate with the severity of neuropsychiatric impairment and since MR spectra return towards normal after treatment, the technique may be of use in objective patient monitoring and in assessing the effectiveness of various treatment regimens. 展开更多
关键词 Hepatic encephalopathy magnetic resonance imaging magnetic resonance spectroscopy Diffusion weighted imaging Arterial spin labeling Functional mri
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原发性中枢神经系统淋巴瘤MRI图像参数与分子病理的关联性分析
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作者 张东阳 王树叶 +3 位作者 刘玥 杨昆鹏 于洪娟 王悦 《中国肿瘤临床》 CAS CSCD 北大核心 2024年第8期401-405,共5页
目的:研究原发性中枢神经系统淋巴瘤(primary central nervous system lymphoma,PCNSL)MRI图像参数与分子病理的关联性。方法:回顾性分析2020年1月至2023年6月就诊于哈尔滨医科大学附属第一医院26例PCNSL患者资料,根据细胞来源、BCL-2... 目的:研究原发性中枢神经系统淋巴瘤(primary central nervous system lymphoma,PCNSL)MRI图像参数与分子病理的关联性。方法:回顾性分析2020年1月至2023年6月就诊于哈尔滨医科大学附属第一医院26例PCNSL患者资料,根据细胞来源、BCL-2表达、Ki-67指数,MAP+布鲁顿酪氨酸激酶抑制剂(Bruton's tyrosine kinase inhibitor,BTKi)治疗反应性将患者归纳至非生发中心B细胞(non-germinal center B-cell,non-GCB)组和生发中心B细胞(germinal center B-cell,GCB)组、Ki-67≥75%组和Ki-67<75%组、BCL-2+组和BCL-2-组、对MAP+BTKi方案治疗有反应组和无反应组。提取患者基线期MRI图像一阶参数如平均值、标准差、方差、变异系数、偏度、峰度、熵,比较其在两组间的差异。结果:方差、峰度、偏度、变异系数等4个参数在组间差异无统计学意义;平均数、标准差、熵这3个参数在Ki-67表达、BCL-2表达组间的差异具有统计学意义;平均数、熵这两个参数在细胞来源、治疗是否有反应性两组间差异具有统计学意义(P<0.05);对于Ki-67指数,3个参数的曲线下面积(AUC)分别为0.731、0.831、0.913;对于BCL-2表达,平均数、标准差的曲线下面积(AUC)分别为0.889和0.938。多参数联合分析时其鉴识效果较利用单个纹理分析定量参数更高。结论:平均值、标准差、熵等3个MRI参数有助于预测PCNSL患者Ki-67、BCL-2的表达,对于治疗具有一定评估作用,有利于术前无创性评估肿瘤的恶性程度并为预后和治疗提供新的依据。 展开更多
关键词 原发中枢神经系统淋巴瘤 磁共振 图像参数 分子病理 布鲁顿酪氨酸激酶抑制剂
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Targeted prostate biopsy: value of multiparametric magnetic resonance imaging in detection of localized cancer 被引量:3
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作者 Jesse D Le Jiaoti Huang Leonard S Marks 《Asian Journal of Andrology》 SCIE CAS CSCD 2014年第4期522-529,共8页
Prostate cancer is the second most common cancer in men, with 1.1 million new cases worldwide reported by the World Health Organization in one recent year. Transrectal ultrasound (TRUS)-guided biopsy has been used f... Prostate cancer is the second most common cancer in men, with 1.1 million new cases worldwide reported by the World Health Organization in one recent year. Transrectal ultrasound (TRUS)-guided biopsy has been used for the diagnosis of prostate cancer for over 2 decades, but the technique is usually blind to cancer location. Moreover, the false negative rate of TRUS biopsy has been reported to be as high as 47%. Multiparametric magnetic resonance imaging (mp-MRI) includes T1- and T2-weighted imaging as well as dynamic contrast-enhanced (DCE) and diffusion-weighted imaging (DWI). mp-MRI is a major advance in the imaging of prostate cancer, enabling targeted biopsy of suspicious lesions. Evolving targeted biopsy techniquesmincluding direct in-bore biopsy, cognitive fusion and software-based MRI-ultrasound (MRI-US) fusion--have led to a several-fold improvement in cancer detection compared to the earlier method. Importantly, the detection of clinically significant cancers has been greatly facilitated by targeting, compared to systematic biopsy alone. Targeted biopsy via MRI-US fusion may dramatically alter the way prostate cancer is diagnosed and managed. 展开更多
关键词 fusion biopsy magnetic resonance imaging mri prostate biopsy prostate cancer targeted biopsy ULTRASOUND
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Usefulness of two-point Dixon fat-water separation technique in gadoxetic acid-enhanced liver magnetic resonance imaging 被引量:2
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作者 Ying Ding Sheng-Xiang Rao +2 位作者 Cai-Zhong Chen Ren-Chen Li Meng-Su Zeng 《World Journal of Gastroenterology》 SCIE CAS 2015年第16期5017-5022,共6页
AIM:To compare differences between volumetric interpolated breath-hold examination(VIBE) using two-point Dixon fat-water separation(Dixon-VIBE) and chemically selective fat saturation(FS-VIBE) with magnetic resonance ... AIM:To compare differences between volumetric interpolated breath-hold examination(VIBE) using two-point Dixon fat-water separation(Dixon-VIBE) and chemically selective fat saturation(FS-VIBE) with magnetic resonance imaging examination.METHODS:Forty-nine patients were included, who were scanned with two VIBE sequences(Dixon-VIBE and FS-VIBE) in hepatobiliary phase after gadoxetic acid administration.Subjective evaluations including sharpness of tumor, sharpness of vessels, strength and homogeneity of fat suppression, and artifacts that were scored using a 4-point scale.The liver-to-lesion contrast was also calculated and compared.RESULTS:Dixon-VIBE with water reconstruction had significantly higher subjective scores than FS-VIBE in strength and homogeneity of fat suppression(< 0.0001) but lower scores in sharpness of tumor(P < 0.0001), sharpness of vessels(P = 0.0001), and artifacts(P = 0.034).The liver-to-lesion contrast on Dixon-VIBE images was significantly lower than that on FS-VIBE(16.6% ± 9.4% vs 23.9% ± 12.1%, P = 0.0001).CONCLUSION:Dixon-VIBE provides stronger and more homogenous fat suppression than FS-VIBE, while has lower clarity of focal liver lesions in hepatobiliary phase after gadoxetic acid administration. 展开更多
关键词 Dixon-volumetric interpolated breath-holdexamination FAT saturation-volumetric interpolatedbreath-hold examination Gadoxetic acid Volumetricinterpolated BREATH-HOLD examination magnetic resonance imaging
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Magnetic resonance imaging for prostate cancer clinical application 被引量:2
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作者 Bing Li Yong Du +3 位作者 Hanfeng Yang Yayong Huang Jun Meng Dongmei Xiao 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2013年第2期240-249,共10页
As prostate cancer is a biologically heterogeneous disease for which a variety of treatment options are available, the major objective of prostate cancer imaging is to achieve more precise disease characterization. In... As prostate cancer is a biologically heterogeneous disease for which a variety of treatment options are available, the major objective of prostate cancer imaging is to achieve more precise disease characterization. In clinical practice, magnetic resonance imaging (MRI) is one of the imaging tools for the evaluation of prostate cancer, the fusion of MRI or dynamic contrast-enhanced MRI (DCE-MRI) with magnetic resonance spectroscopic imaging (MRSI) is improving the evaluation of cancer locafon, size, and extent, while providing an indication of tumor aggressiveness. This review summarizes the role of MRI in the application of prostate cancer and describes molecular MRI techniques (including MRSI and DCE-MRI) for aiding prostate cancer management. 展开更多
关键词 Prostate cancer magnetic resonance imaging mri fimctional mri molecular MR[
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MRI动态增强技术对垂体微腺瘤的诊断价值
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作者 余敏 黄宁 +1 位作者 周金林 余燕 《中国实用神经疾病杂志》 2024年第7期858-862,共5页
目的探究磁共振动态增强技术(DCE-MRI)在垂体微腺瘤(PMA)诊断中的价值。方法纳入巴中市中心医院及重庆医科大学附属第二医院120例疑似PMA患者,所有患者入院后行DCE-MRI检查,以临床病理检查为金标准,分析DCE-MRI对PMA的诊断价值,对比微... 目的探究磁共振动态增强技术(DCE-MRI)在垂体微腺瘤(PMA)诊断中的价值。方法纳入巴中市中心医院及重庆医科大学附属第二医院120例疑似PMA患者,所有患者入院后行DCE-MRI检查,以临床病理检查为金标准,分析DCE-MRI对PMA的诊断价值,对比微腺瘤组织与邻近组织的DCE-MRI信号强度曲线类型、DCE-MRI参数及不同质地垂体瘤组织的DCE-MRI参数。结果经病理诊断,120例患者中PMA患者阳性83例,阴性37例。DCE-MRI诊断81例阳性,39例阴性,其中漏诊5例,误诊3例,诊断敏感度93.98%,特异度91.89%,准确率93.33%,阳性预测值96.30%,阴性预测值87.18%,Kappa值0.846,与病理诊断具有较高的一致性。PMA组织DCE-MRI信号强度以Ⅱ型、Ⅲ型为主,邻近正常组织以Ⅰ型、Ⅱ型为主,差异有统计学意义(P<0.05)。PMA组织K_(ep)、K^(trans)、Ve、MSI值显著低于邻近正常组织,TTP值显著高于邻近正常组织(P<0.05)。83例PMA中23例质硬,60例质软,质硬组K_(ep)、TTP值显著高于质软组(P<0.05),K^(trans)、Ve、MSI值显著低于质软组(P<0.05)。结论DCE-MRI扫描可有效提高PMA检出率,通过扫描获得的TIC类型、DCE-MRI参数可用于鉴别肿瘤病灶大小、范围、质地等,为临床手术提供重要参考。 展开更多
关键词 垂体微腺瘤 垂体瘤 磁共振动态增强技术 病理检查 诊断价值
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Nasopharyngeal adenoid cystic carcinoma: magnetic resonance imaging features in ten cases 被引量:8
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作者 Xue-Wen Liu Chuan-Miao Xie +7 位作者 Hui Li Rong Zhang Zhi-Jun Geng Yun-Xian Mo Jing Zhao Mu-Yan Cai Yan-Chun Lv Pei-Hong Wu 《Chinese Journal of Cancer》 SCIE CAS CSCD 2012年第1期19-28,共10页
Nasopharyngeal adenoid cystic carcinoma (NACC) is a rare malignancy with high local invasiveness. To date, there is no consensus on the imaging characteristics of NACC. To address this, we retrospectively reviewed 10 ... Nasopharyngeal adenoid cystic carcinoma (NACC) is a rare malignancy with high local invasiveness. To date, there is no consensus on the imaging characteristics of NACC. To address this, we retrospectively reviewed 10 cases of NACC and summarized the magnetic resonance imaging (MRI) features. MR images of 10 patients with histologically validated NACC were reviewed by two experienced radiologists. The location, shape, margin, signal intensity, lesion texture, contrast enhancement patterns, local invasion, and cervical lymphadenopathy of all tumors were evaluated. Clinical and pathologic records were also reviewed. No patients were positive for antibodies against Epstein-Barr virus (EBV). The imaging patterns of primary tumors were classified into two types as determined by location, shape, and margin. Of all patients, 7 had tumors with a type 1 imaging pattern and 3 had tumors with a type 2 imaging pattern. The 4 tubular NACCs were all homogeneous tumors, whereas 3 (60%) of 5 cribriform NACCs and the sole solid NACC were heterogeneous tumors with separations or central necrosis on MR images. Five patients had perineural infiltration and intracranial involvement, and only 2 had cervical lymphadenopathy. Based on these results, we conclude that NACC is a local, aggressive neoplasm that is often negative for EBV infection and associated with a low incidence of cervical lymphadenopathy. Furthermore, MRI features of NACC vary in locations and histological subtypes. 展开更多
关键词 磁共振成像 腺样囊性癌 淋巴结肿大 恶性肿瘤 磁共振图像 成像模式 信号强度
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