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Investigating the relationship between intracranial atherosclerotic plaque remodelling and diabetes using high-resolution vessel wall imaging
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作者 Yong-Qian Mo Hai-Yu Luo +5 位作者 Han-Wen Zhang Yu-Feng Liu Kan Deng Xiao-Lei Liu Biao Huang Fan Lin 《World Journal of Diabetes》 SCIE 2024年第1期72-80,共9页
BACKGROUND Intracranial atherosclerosis,a leading cause of stroke,involves arterial plaque formation.This study explores the link between plaque remodelling patterns and diabetes using high-resolution vessel wall imag... BACKGROUND Intracranial atherosclerosis,a leading cause of stroke,involves arterial plaque formation.This study explores the link between plaque remodelling patterns and diabetes using high-resolution vessel wall imaging(HR-VWI).AIM To investigate the factors of intracranial atherosclerotic remodelling patterns and the relationship between intracranial atherosclerotic remodelling and diabetes mellitus using HR-VWI.METHODS Ninety-four patients diagnosed with middle cerebral artery or basilar artery INTRODUCTION Intracranial atherosclerotic disease is one of the main causes of ischaemic stroke in the world,accounting for approx-imately 10%of transient ischaemic attacks and 30%-50%of ischaemic strokes[1].It is the most common factor among Asian people[2].The adaptive changes in the structure and function of blood vessels that can adapt to changes in the internal and external environment are called vascular remodelling,which is a common and important pathological mechanism in atherosclerotic diseases,and the remodelling mode of atherosclerotic plaques is closely related to the occurrence of stroke.Positive remodelling(PR)is an outwards compensatory remodelling where the arterial wall grows outwards in an attempt to maintain a constant lumen diameter.For a long time,it was believed that the degree of stenosis can accurately reflect the risk of ischaemic stroke[3-5].Previous studies have revealed that lesions without significant luminal stenosis can also lead to acute events[6,7],as summarized in a recent meta-analysis study in which approximately 50%of acute/subacute ischaemic events were due to this type of lesion[6].Research[8,9]has pointed out that the PR of plaques is more dangerous and more likely to cause acute ischaemic stroke.Previous studies[10-13]have found that there are specific vascular remodelling phenomena in the coronary and carotid arteries of diabetic patients.However,due to the deep location and small lumen of intracranial arteries and limitations of imaging techniques,the relationship between intracranial arterial remodelling and diabetes is still unclear.In recent years,with the development of magnetic resonance technology and the emergence of high-resolution(HR)vascular wall imaging,a clear and multidimensional display of the intracranial vascular wall has been achieved.Therefore,in this study,HR wall imaging(HR-VWI)was used to display the remodelling characteristics of bilateral middle cerebral arteries and basilar arteries and to explore the factors of intracranial vascular remodelling and its relationship with diabetes. 展开更多
关键词 high-resolution vessel wall imaging Intracranial atherosclerosis Vascular remodelling magnetic resonance imaging
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Non-iterative image reconstruction from sparse magnetic resonance imaging radial data without priors
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作者 Gengsheng L.Zeng Edward V.DiBella 《Visual Computing for Industry,Biomedicine,and Art》 2020年第1期84-91,共8页
The state-of-the-art approaches for image reconstruction using under-sampled k-space data are compressed sensing based.They are iterative algorithms that optimize objective functions with spatial and/or temporal const... The state-of-the-art approaches for image reconstruction using under-sampled k-space data are compressed sensing based.They are iterative algorithms that optimize objective functions with spatial and/or temporal constraints.This paper proposes a non-iterative algorithm to estimate the un-measured data and then to reconstruct the image with the efficient filtered backprojection algorithm.The feasibility of the proposed method is demonstrated with a patient magnetic resonance imaging study.The proposed method is also compared with the state-of-the-art iterative compressed-sensing image reconstruction method using the total-variation optimization norm. 展开更多
关键词 Tomographic image reconstruction Under-sampled measurements fast magnetic resonance imaging Analytics reconstruction
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High-resolution Magnetic Resonance Imaging of Moyamoya Disease 被引量:8
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作者 Le-Bao Yu Qian Zhang +2 位作者 Zhi-Yong Shi Ming-Qiu Wang Dong Zhang 《Chinese Medical Journal》 SCIE CAS CSCD 2015年第23期3231-3237,共7页
Objective: To introduce the imaging characteristics of moyamoya disease (MMD) using high-resolution magnetic resonance imaging (HR-MRI) and to discuss the role of HR-MRI in differentiating MMD from other intracra... Objective: To introduce the imaging characteristics of moyamoya disease (MMD) using high-resolution magnetic resonance imaging (HR-MRI) and to discuss the role of HR-MRI in differentiating MMD from other intracranial artery diseases, especially intracranial atherosclerotic disease (ICAD). Data Sources: This review was based on the data in articles published between 2005 and 2015, which were obtained from PubMed. The keywords included HR-MRI, MMD, ICAD, and intracranial artery diseases. Study Selection: Articles related to HR-MRI for MMD or other intracranial artery diseases were selected for review. Results: There are differences between the characteristic patterns of HR-MRI in MMD and ICAD. MMD is associated with inward remodeling, smaller outer diameters, concentric occlusive lesions and homogeneous signal intensity, while ICAD is more likely to be associated with outward remodeling, normal outer diameters, eccentric occlusive lesions, and heterogeneous signal intensity. Other intracranial artery diseases, such as dissection and vasculitis, also have distinctive characteristics in HR-MRI. HR-MRI may become a useful tool for the differential diagnosis of MMD in the future. Conclusions: HR-MRI of MMD provides a more in-depth understanding of MMD, and it is helpful in evaluating pathological changes in the vessel wall and in differentiating MMD from other intracranial artery steno-occlusive diseases, particularly ICAD.以 展开更多
关键词 ATHEROSCLEROSIS high-resolution magnetic resonance imaging Intracranial Artery Steno-occlusive Disease lntracrania Atherosclerotic Disease Moyamoya Disease
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FibroScan、MRI-PDFF和FAST评分识别高危非酒精性脂肪性肝炎患者临床应用研究
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作者 杨逸铭 李晓环 +4 位作者 刘玉品 欧金龙 黎胜 石美凤 汪印强 《实用肝脏病杂志》 CAS 2024年第5期701-704,共4页
目的探讨瞬时弹性成像(FibroScan)、磁共振质子密度脂肪分数(MRI-PDFF)和FAST评分识别高危非酒精性脂肪性肝炎(NASH)患者的应用价值。方法2017年6月~2021年12月我院诊治的非酒精性脂肪肝病(NAFLD)患者107例,均接受肝活检和MRI-PDFF、Fib... 目的探讨瞬时弹性成像(FibroScan)、磁共振质子密度脂肪分数(MRI-PDFF)和FAST评分识别高危非酒精性脂肪性肝炎(NASH)患者的应用价值。方法2017年6月~2021年12月我院诊治的非酒精性脂肪肝病(NAFLD)患者107例,均接受肝活检和MRI-PDFF、FibroScan和血清学检查,计算FAST、FIB-4和APRI指数。采用单因素和多因素Logistic回归分析,应用受试者工作特征(ROC)曲线分析指标识别高危NASH患者的诊断效能。结果在107例NAFLD患者中,经肝组织病理学检查诊断高危非酒精性脂肪性肝炎(NASH)患者13例(12.1%),单纯性脂肪肝和非高危NASH患者94例(87.9%);高危NASH组LSM、FAST评分和APRI指数显著高于非高危组(P<0.05);多因素Logistic回归分析显示,FibroScan检测的肝脏硬度(LSM)是高危NASH患者的独立影响因素(P<0.05);ROC曲线分析显示LSM、FAST和APRI识别高危NASH患者有统计学意义(P<0.05),其曲线下面积(AUC)分别为0.795、0.713和0.682,以LSM的诊断效能最优,其排除截断点诊断的敏感度和特异度分别为92.3%和54.3%,而纳入截断点诊断则为53.8%和90.4%。结论对于FibroScan检测诊断的NAFLD患者,其LSM也同期升高高度提示NASH的存在,应进一步检查,以期早期干预。 展开更多
关键词 非酒精性脂肪性肝炎 瞬时弹性成像 磁共振质子密度脂肪分数 fast评分 诊断
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Non-invasive assessment of intracranial wall shear stress using high-resolution magnetic resonance imaging in combination with computational fluid dynamics technique
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作者 Yuwen Chen Jia Liu +10 位作者 Mingli Li Yannan Yu Zhengzheng Yan Wenshin Shiu Bokai Wu Zaiheng Cheng Yao Meng Yang Liu Weizhuang Yuan Zongmuyu Zhang Weihai Xu 《Fundamental Research》 CAS 2022年第2期329-334,共6页
In vivo studies on association between wall shear stress(WSS)and intracranial plaque are deficient.Based on the three-dimensional T1-weighted high-resolution magnetic resonance imaging(3DT1 HR-MRI)data of patients wit... In vivo studies on association between wall shear stress(WSS)and intracranial plaque are deficient.Based on the three-dimensional T1-weighted high-resolution magnetic resonance imaging(3DT1 HR-MRI)data of patients with low-grade stenotic(<50%)atherosclerotic middle cerebral artery(MCA)and subjects with normal MCA,we built a three-dimensional reconstructed WSS model by computational fluid dynamics(CFD)technique.Three-dimensional registration of the CFD model to the HR-MRI was performed with projections based on the resolution and thickness of the images.The relationships between the Wss at each side of the vessel wall and plaque location were analyzed.A total of 94 MCA plaques from 43 patients and 50 normal MCAs were analyzed.In the normal MCAs,WSS was lower at the ventral-inferior wall than at the dorsal-superior wall(proximal segment,p<0.001;middle segment,p<0.001)and lower at the inner wall than at the outer wall of the MCA curve(p<0.001).In atherosclerotic MCAs,similar low Wss regions were observed where plaques developed.The WSS ratio of the ventral-inferior wall to the dorsal-superior wall in atherosclerotic MCAs was lower than that in normal MCAs(p=0.002).The WSS_(inmer-outer)ratio in atherosclerotic MCAs was lower than that in normal MCAs(p=0.002).Low WSS was associated with MCA atherosclerosis formation and occurred mainly at the ventral inferior wall,which was anatomically opposite the orifices of penetrating arteries,and at the inner wall of the MCA curve.Overall,the results were well consistent with the low WSS theory in atherosclerosis formation.The reconstructed WSS model is a promising novel method for assessing an individualized vascular profile once validated by further studies. 展开更多
关键词 Intracranial atherosclerosis Wall shear stress Atherosclerotic plaque high-resolution magnetic resonance imaging Computational fluid dynamics
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igh-resolution Magnetic Resonance Vessel Wall Imaging for Intracranial Arterial Stenosis 被引量:30
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作者 Xian-Jin Zhu Wu Wang Zun-Jing Liu 《Chinese Medical Journal》 SCIE CAS CSCD 2016年第11期1363-1370,共8页
Objective: To discuss the feasibility and clinical value of high-resolution magnetic resonance vessel wall imaging (HRMR VWI) for intracranial arterial stenosis. Date Sources: We retrieved information from PubMed ... Objective: To discuss the feasibility and clinical value of high-resolution magnetic resonance vessel wall imaging (HRMR VWI) for intracranial arterial stenosis. Date Sources: We retrieved information from PubMed database up to December 2015, using various search terms including vessel wall imaging (VWI), high-resolution magnetic resonance imaging, intracranial arterial stenosis, black blood, and intracranial atherosclerosis. Study Selection: We reviewed peer-reviewed articles printed in English on imaging technique of VWI and characteristic findings of various intracranial vasculopathies on VWI. We organized this data to explain the value of VWI in clinical application. Results: VWI with black blood technique could provide high-quality images with submillimeter voxel size, and display both the vessel wall and lumen of intracranial artery simultaneously. Various intracranial vasculopathies (atherosclerotic or nonatherosclerotic) had differentiating features including pattern of wall thickening, enhancement, and vessel remodeling on VWI. This technique could be used for determining causes of stenosis, identification of stroke mechanism, risk-stratifying patients, and directing therapeutic management in clinical practice. In addition, a new morphological classification based on VWI could be established for predicting the efficacy of endovascular therapy. Conclusions: This review highlights the value of HRMR VWI for discrimination of different intracranial vasculopathies and directing therapeutic management. 展开更多
关键词 Black Blood high-resolution magnetic resonance images Vessel Wall imaging
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Imaging related to underlying immunological and pathological processes in COVID-19
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作者 Elena Ilieva Alexandra Boyapati +4 位作者 Lyubomir Chervenkov Milena Gulinac Jordan Borisov Kamelia Genova Tsvetelina Velikova 《World Journal of Clinical Infectious Diseases》 2022年第1期1-19,共19页
The introduction of coronavirus disease-2019(COVID-19)as a global pandemic has contributed to overall morbidity and mortality.With a focus on understanding the immunology and pathophysiology of the disease,these featu... The introduction of coronavirus disease-2019(COVID-19)as a global pandemic has contributed to overall morbidity and mortality.With a focus on understanding the immunology and pathophysiology of the disease,these features can be linked with the respective findings of imaging studies.Thus,the constellation between clinical presentation,histological,laboratory,immunological,and imaging results is crucial for the proper management of patients.The purpose of this article is to examine the role of imaging during the particular stages of severe acute respiratory syndrome coronavirus 2 infection–asymptomatic stage,typical and atypical COVID-19 pneumonia,acute respiratory distress syndrome,multiorgan failure,and thrombosis.The use of imaging methods to assess the severity and duration of changes is crucial in patients with COVID-19.Radiography and computed tomography are among the methods that allow accurate characterization of changes. 展开更多
关键词 Coronavirus disease-2019 Ultrasound Computed tomography magnetic resonance imaging Ground-glass opacity Acute respiratory distress syndrome Cytokine storm COVID-19 reporting and data system high-resolution computed tomography Severe acute respiratory syndrome coronavirus 2
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高分辨率磁共振成像对臂丛神经损伤的预测价值
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作者 蔡剡军 王国松 +1 位作者 江茜 黄锦金 《中国微侵袭神经外科杂志》 CAS 2024年第4期226-231,共6页
目的探析高分辨率磁共振(MRI)成像对臂丛神经损伤(brachial plexus injury,BPI)的预测价值。方法对59例临床拟诊BPI的病例行高分辨MRI检查。根据年龄,将年龄≥65岁者纳入老年组,18~64岁者纳入青中年组。观察两组臂丛神经显像效果,计算... 目的探析高分辨率磁共振(MRI)成像对臂丛神经损伤(brachial plexus injury,BPI)的预测价值。方法对59例临床拟诊BPI的病例行高分辨MRI检查。根据年龄,将年龄≥65岁者纳入老年组,18~64岁者纳入青中年组。观察两组臂丛神经显像效果,计算臂丛神经成像评分、臂丛神经信噪比(signal-to-noise ratio,SNR)、对比度噪声比(contrast-to-noise ratio,CNR)和背景抑制评分,分析高分辨率MRI成像对不同年龄段BPI的预测价值。结果59例临床拟诊BPI病例中,MRI诊断为BPI 20例,其余正常。20例经MRI确诊BPI中,老年组7例和青中年组13例。老年组节前损伤2例(28.57%),节后损伤5例(71.43%);青中年组节前损伤5例(38.46%),节后损伤8例(61.54%)。两组病人臂丛神经成像评分由低到高依次为三维双回波稳态(3D-DESS)序列增强扫描、三维短时反转恢复快速自旋回波(3D SPACE)序列平扫、DESS序列平扫和SPACE序列增强扫描,且在干3、支5 DESS序列平扫、股6 DESS序列增强扫描及支5 SPACE序列增强扫描上,老年组臂丛神经成像评分明显低于青中年组(P<0.05)。两组SNR、CNR由低到高依次为DESS增强、SPACE平扫、DESS平扫和SPACE增强(P<0.05),两组背景组织抑制评分比较,SPACE增强最高,其次为DESS平扫,DESS增强和SPACE平扫最低(P<0.05)。老年组DESS序列增强扫描的SNR、CNR以及SPACE序列平扫、增强扫描的SNR、CNR均明显低于青中年组(P<0.05)。结论与青中年BPI病人相比,老年BPI病人臂丛神经成像评分、SNR与CNR更低,MRI 3D SPACE序列可清晰显示臂丛神经内部信号改变,同时降低神经周围背景组织信号干扰,对于显示神经损伤优势明显,值得临床优先选择。 展开更多
关键词 臂丛神经损伤 三维短时反转恢复快速自旋回波序列 磁共振成像
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应用于人脑胶质淋巴系统的磁共振成像技术研究进展 被引量:2
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作者 陈泽然 黄梦颖 +2 位作者 曾利川 金硕果 尹海燕 《中国全科医学》 CAS 北大核心 2024年第26期3314-3319,共6页
胶质淋巴系统是神经科学领域近期发现的解剖结构,具有调节间质液运动、废物清除和潜在的大脑免疫等功能,在中枢神经系统的生理及病理中发挥重要作用。随着影像学技术的发展,越来越多的磁共振成像(MRI)技术被应用于人脑胶质淋巴系统的研... 胶质淋巴系统是神经科学领域近期发现的解剖结构,具有调节间质液运动、废物清除和潜在的大脑免疫等功能,在中枢神经系统的生理及病理中发挥重要作用。随着影像学技术的发展,越来越多的磁共振成像(MRI)技术被应用于人脑胶质淋巴系统的研究,目前常用的MRI技术有动态对比增强磁共振成像技术、沿血管周围间隙扩散张量成像分析技术及新型多模态超快速磁共振技术等,本文就这些技术在脑胶质淋巴系统的应用现状进行汇总综述,以期为胶质淋巴系统的影像学研究提供参考。 展开更多
关键词 神经胶细胞类淋巴系统 中枢神经系统 淋巴系统 磁共振成像 动态对比增强磁共振 沿血管周围间隙扩散张量成像分析 超快速磁共振成像
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基于深度学习技术的TSE-T2WI在纵隔MRI中的应用价值
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作者 武鹏飞 徐海 +2 位作者 李泓渊 沈杰 王建伟 《南京医科大学学报(自然科学版)》 CAS 北大核心 2024年第6期797-801,共5页
目的:探讨基于深度学习重建(deep learning reconstruction,DLR)技术的快速自旋回波(turbo spin echo,TSE)T2加权成像(T2 weighted imaging,T2WI)序列提高纵隔T2WI图像质量和减少扫描时间的应用价值。方法:前瞻性收集35例纵隔病变的患... 目的:探讨基于深度学习重建(deep learning reconstruction,DLR)技术的快速自旋回波(turbo spin echo,TSE)T2加权成像(T2 weighted imaging,T2WI)序列提高纵隔T2WI图像质量和减少扫描时间的应用价值。方法:前瞻性收集35例纵隔病变的患者进行纵隔常规T2WI序列和基于DLR的T2WI(T2WIDLR)序列扫描。由2位放射科医师各自独立对两组图像的伪影、图像清晰度、病灶的细节显示和整体图像质量进行定性评分,并测量和比较两组图像的病灶信噪比(SNR_(病灶))和病灶与竖直肌的对比噪声比(CNR_(病灶/肌肉))。结果:T2WIDLR在伪影、图像清晰度、病灶细节显示和整体图像质量的评分均优于常规T2WI(P均<0.001)。T2WIDLR序列图像的SNR和CNR均优于常规T2WI序列(P均<0.001)。结论:与常规T2WI序列相比,T2WI_(DLR)序列的运动伪影更少,图像清晰度、病灶细节显示和整体图像质量更优,图像SNR和CNR更高,在纵隔疾病的临床应用中有较大潜力。 展开更多
关键词 纵隔 深度学习 磁共振成像 快速自旋回波
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FasT-Fix和半月板箭修复半月板术后磁共振成像的信号特点 被引量:9
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作者 江东 敖英芳 +2 位作者 苗羽 郑卓肇 余家阔 《中国微创外科杂志》 CSCD 2013年第11期1021-1025,共5页
目的 比较FasT-Fix和可吸收半月板箭(Arrow)缝合半月板术后磁共振(MRI)的信号特点和差异.方法 2002年9月~ 2008年12月,112名患者(其中12例内外侧半月板均缝合,共124处半月板缝合)接受关节镜下半月板缝合术,FasT-Fix组73处,Arrow... 目的 比较FasT-Fix和可吸收半月板箭(Arrow)缝合半月板术后磁共振(MRI)的信号特点和差异.方法 2002年9月~ 2008年12月,112名患者(其中12例内外侧半月板均缝合,共124处半月板缝合)接受关节镜下半月板缝合术,FasT-Fix组73处,Arrow组51处.患者术前及术后接受MRI扫描,比较两种缝合方式的MRI信号特点和差异,并以二次关节镜探查的结果作为金标准计算MRI对两种缝合方式术后愈合情况的诊断价值.结果 二次关节镜探查证实FasT-Fix组和半月板箭组的愈合率分别为74.0% (54/73)和88.2% (45/51) (Х^2 =3.794,P=0.051);MRI综合T2序列对Arrow组愈合情况诊断的准确性(80.4%,41/51)高于FasT-Fix修复组(65.8%,48/73),但差异无显著性(Х^2=3.176,P=0.075);在综合T2序列中,FasT-Fix组中未愈合半月板出现3度信号的比例[84.2% (16/19) vs.50.0% (3/6),Х^2=26.142,P=0.000]和累及层面[中位数4(1~6) vs.1(0~3),Z=3.060,P=0.002]均明显高于Arrow组.结论 MRI综合T2序列对半月板箭修复术后的愈合诊断更准确,FasT-Fix修复术后的半月板更易出现3度信号. 展开更多
关键词 半月板缝合 fast-FIX 半月板箭 磁共振 二次关节镜
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3D BH-GRASE序列与3D RT-TSE序列进行MRCP的应用价值分析
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作者 石容容 丁玉姣 +1 位作者 贺俊峰 徐秋贞 《医学影像学杂志》 2024年第1期62-65,共4页
目的探讨对比分析三维屏气梯度-自旋回波(3D BH-GRASE序列)与三维呼吸触发快速自旋回波(3D RTTSE)序列进行磁共振胰胆管成像(MRCP)的应用价值。方法选取在我院因怀疑胰胆管病变而行腹部MRI检查的患者,均接受3D RT-TSE序列与3D BH-GRASE... 目的探讨对比分析三维屏气梯度-自旋回波(3D BH-GRASE序列)与三维呼吸触发快速自旋回波(3D RTTSE)序列进行磁共振胰胆管成像(MRCP)的应用价值。方法选取在我院因怀疑胰胆管病变而行腹部MRI检查的患者,均接受3D RT-TSE序列与3D BH-GRASE序列MRCP扫描。比较两种序列扫描时间、图像质量评分及显示病变情况。结果3D BH-GRASE序列的扫描时间为(16.4±1.7)s明显短于3D RT-TSE序列的(258.6±31.2)s,差异有统计学意义(P<0.05);3D BH-GRASE序列扫描图像胆囊、肝内胆管、胆囊管、胰管、胆总管等主要分支评分均明显高于3D RTTSE序列,差异有统计学意义(P<0.05);两种扫描序列方法对各区域病变检出率差异无统计学意义(P>0.05)。结论MRCP检查应用3D BH-GRASE序列扫描能够保证图像质量及显示病变,同时缩短扫描时间。 展开更多
关键词 胆系疾病 胰胆管 磁共振成像 梯度-自旋回波 快速自旋回波
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MRI预测乳腺肿块良恶性的研究进展
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作者 胡朝(综述) 罗光华(审校) 《现代医药卫生》 2024年第8期1383-1386,1392,共5页
随着医疗水平的进步,乳腺疾病的检出率越来越高,特别是乳腺肿块。早期对肿块良恶性进行精准预测,不仅可以提高患者生存率,而且可以降低治疗成本。随着动态对比增强磁共振成像、扩散加权成像和磁共振光谱等各种技术的出现,早期预测乳腺... 随着医疗水平的进步,乳腺疾病的检出率越来越高,特别是乳腺肿块。早期对肿块良恶性进行精准预测,不仅可以提高患者生存率,而且可以降低治疗成本。随着动态对比增强磁共振成像、扩散加权成像和磁共振光谱等各种技术的出现,早期预测乳腺肿块良恶性成为可能。该文主要对磁共振成像预测乳腺肿块良恶性的研究进展进行综述。 展开更多
关键词 乳腺肿块 乳腺癌 磁共振成像 超快速动态增强 磁共振波谱 影像组学
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Magnetic Resonance Three-dimensional Cube Technique in the Measurement of Piglet Femoral Anteversion 被引量:2
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作者 Dong-Mei Sun Shi-Nong Pan +3 位作者 En-Bo Wang Li-Qiang Zheng Wen-Li Guo Xi-Hu Fu 《Chinese Medical Journal》 SCIE CAS CSCD 2016年第13期1584-1591,共8页
Background: The accurate measurement of the femoral anteversion (FA) angle is always a topic of much debate in the orthopedic surgery and radiology research. We aimed to explore a new FA measurement method to acqui... Background: The accurate measurement of the femoral anteversion (FA) angle is always a topic of much debate in the orthopedic surgery and radiology research. We aimed to explore a new FA measurement method to acquire accurate results without radiation damage using piglet model. Methods: A total of thirty piglets were assigned to two groups based on the age. Bilateral femora were imaged with 3.0-T magnetic resonance (MR) and 64-slice computed tomography (CT) examinations on all piglets. FA was measured on MR-three-dimensional (3D) postprocessing software with a four-step method: initial validation of the femoral condylar axis, validation of the condylar plane, validation of the femoral neck axis, and line-plane angle measurement of FA. After MR and CT examinations, all piglets were sacrificed and their degree of FA was measured using their excised, dried femora. MR, CT, and dried-femur measurement results were analyzed statistically; M R and CT measurements were compared for accuracy against each other and against the gold standard dried femur measurement. Results: In both groups, the mean FA value measured by MR was lower than that measured by CT. A statistically significant difference was observed between CT- and dried-femur measurements but not between MR- and dried-femur measurements. A higher correlation (0.783 vs. 0.408) and a higher consistency (0.863 vs. 0.578) with dried-femur measurement results were seen for MR measurements than CT measurements in the 1 -week age group. However, in the 8-week age group, similar correlations (0.707 vs. 0.669) and consistencies (0.864 vs. 0.82 l ) were observed. Conclusions: Noninvasive MR-3D-Cube reconstruction was able to accurately measure FA in piglets. Particularly in the 1-week age group with a larger proportion of cartilaginous structures, the correlation and consistency between MR- and dried-femur measurement results were higher than those between CT- and dried-femur measurements, suggesting that MR may be a new useful examination tool for FA-related diseases in children. 展开更多
关键词 Femoral Anteversion HIP magnetic resonance imaging PIGLET Three-dimensional fast Spin Echo Cube
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一种改进的FastICA算法及其在fMRI数据中的仿真应用 被引量:1
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作者 彭尧 熊馨 《软件导刊》 2018年第4期67-70,共4页
为了更有效地去除功能磁共振成像(functional magnetic resonance imaging,fMRI)数据中所包含的大量噪声信号,研究了快速独立分量分析(Fast Independent Component Analysis,FastICA)算法,针对该算法在处理低信噪比的fMRI数据时估计精... 为了更有效地去除功能磁共振成像(functional magnetic resonance imaging,fMRI)数据中所包含的大量噪声信号,研究了快速独立分量分析(Fast Independent Component Analysis,FastICA)算法,针对该算法在处理低信噪比的fMRI数据时估计精度降低问题,采用修正白化矩阵方法改进FastICA算法,与传统的FastICA算法分别对fMRI数据进行去噪仿真分析。对比两种方法去噪结果,发现改进的FastICA算法能更有效地去除fMRI数据中的噪声信号,为剔除fMRI伪迹,提高fMRI数据预处理效果奠定了坚实的科学基础。 展开更多
关键词 功能磁共振成像 fastICA 白化矩阵 仿真
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Imaging traumatic facial nerve injuries:a narrative review of current strategies and future directions for cranial nerve imaging
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作者 Néha Datta Ethan Fung +2 位作者 Adam Hatala Brooks Melnyk Erika Bradley 《Plastic and Aesthetic Research》 2023年第1期155-163,共9页
Traumatic facial nerve injuries can result in temporary or permanent loss of function.Restoration of facial expression may occur spontaneously or require surgical intervention.Although thorough examination and history... Traumatic facial nerve injuries can result in temporary or permanent loss of function.Restoration of facial expression may occur spontaneously or require surgical intervention.Although thorough examination and history can localize the site of facial nerve damage,it can be difficult to predict if and when recovery will occur.This is salient because the window for optimal outcomes from surgical re-neurotization can be as short as 1 to 2 years,after which functional loss may be irreversible.It is essential to offer patients the most appropriate treatment plan based on prognosis,and imaging plays an essential role in localizing the site and morphology of nerve injury.Multiple imaging modalities have been used to evaluate the facial nerve,including computed tomography(CT)and,more recently,advanced magnetic resonance imaging(MRI)and ultrasound(US).CT and MRI are more commonly implemented;however,Diffusion tensor tractography,high-resolution US,and functional US are gaining traction for studying cranial nerve pathology.Until recently,the morphology of facial nerve and other cranial nerve injuries could only be inferred using non-invasive diagnostic techniques.With the advent of newer imaging technologies and techniques to examine nerves,more refined assessment and prognostic information is now possible.This article reviews up-to-date cranial nerve imaging techniques from the last ten years and explores future avenues for facial nerve imaging. 展开更多
关键词 Facial nerve cranial nerve trauma ultrasound high-resolution imaging facial palsy magnetic resonance imaging peripheral nerve
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频率偏移在儿童胸椎快速自旋回波T1WI SPIR抑脂序列图像质量优化中的价值 被引量:1
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作者 吕艳秋 王尉 +3 位作者 高帅一 胡迪 郑丹丹 彭芸 《磁共振成像》 CAS CSCD 北大核心 2023年第8期108-112,117,共6页
目的 优化T1WI频率预饱和结合反转恢复(spectral pre-saturation with inversion recovery, SPIR)抑脂序列的频率偏移值,提升胸椎T1WI SPIR抑脂序列的图像质量。材料与方法 回顾性分析36例患儿胸椎具有9个不同频率偏移值(40、60、80、10... 目的 优化T1WI频率预饱和结合反转恢复(spectral pre-saturation with inversion recovery, SPIR)抑脂序列的频率偏移值,提升胸椎T1WI SPIR抑脂序列的图像质量。材料与方法 回顾性分析36例患儿胸椎具有9个不同频率偏移值(40、60、80、100、120、127、140、160、180 Hz)的T1WI SPIR抑脂序列图像,并进行主客观图像质量评价。利用4分法对椎体脂肪抑脂均一性、背部脂肪抑脂均一性及总体图像质量进行主观评分;计算椎体、脑脊液、椎间盘及脊髓的信噪比(signal-to-noise ratio, SNR)及它们间的对比噪声比(contrast-to-noise ratio, CNR)。采用Kruskal-Wallis非参数检验评价主观图像质量评分,采用单因素方差分析评价SNR和CNR,并采用LSD法作组间两两比较。结果 (1)9个T1WI SPIR序列的椎体脂肪抑脂均一性(F=168.49,P<0.001)、背部脂肪抑脂均一性(F=96.10,P<0.001)及总体图像质量评分(F=27.11,P<0.001)差异均具有统计学意义。频率偏移为40、60、80、100 Hz的4个序列具有最佳的椎体抑脂均一性,4个序列的组间差异无统计学意义;频率偏移为100、120、127、140、160 Hz的5个序列具有最佳的背部抑脂均一性,5个序列间的组间差异无统计学意义;频率偏移为80、100 Hz的2个序列具有最佳的总体图像质量,2个序列的组间差异无统计学意义。(2)6个T1WI SPIR序列的椎体SNR(F=2.83,P<0.05)及椎体与脑脊液间的CNR(F=2.67,P<0.05)的差异具有统计学意义,频率偏移为40、60、80 Hz的3个序列的椎体SNR及椎体与脑脊液的CNR差异无统计学意义,频率偏移为40 Hz序列的椎体SNR优于频率偏移为100、120、127 Hz的序列,其余被研究组织的SNR及组织间的CNR差异在6个序列间无统计学意义。结论 频率偏移在80、100 Hz时,可优化提升胸椎T1WI SPIR序列的总体图像质量。 展开更多
关键词 胸椎病变 脂肪抑制 图像质量 儿童 快速自旋回波 磁共振成像
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磁共振成像人工智能的研究现状及发展前景 被引量:6
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作者 王梅云 《磁共振成像》 CAS CSCD 北大核心 2023年第3期1-5,共5页
随着MRI技术的迅速发展、更加先进的高性能MRI设备的临床投用,以及各种图像后处理软件不断开发,不仅MRI性能和图像质量得到了提高,更重要的是使原来难以发现的组织结构和器官的形态、功能及代谢异常,尤其是一些微小病理改变得以清晰显示... 随着MRI技术的迅速发展、更加先进的高性能MRI设备的临床投用,以及各种图像后处理软件不断开发,不仅MRI性能和图像质量得到了提高,更重要的是使原来难以发现的组织结构和器官的形态、功能及代谢异常,尤其是一些微小病理改变得以清晰显示,显著提高了影像诊断水平,拓宽了应用领域。随着人工智能(artificial intelligence,AI)技术的飞速发展,以及AI在MRI领域研究的不断深入,诸如肿瘤检出、定性诊断、基因表型及预后预测等应用正迅速从试验阶段过渡到临床试用阶段。本文就近年来国内外关于MRI AI方面的研究现状进行总结,并展望未来发展方向,旨在为MRI技术研究及临床转化提供参考依据。 展开更多
关键词 磁共振成像 人工智能 快速重建 图像后处理 诊断 分期 随访 预测
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磁共振增强3D STIR SPACE序列在腰骶神经根中的应用价值
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作者 何荣兴 赖志芬 《中国CT和MRI杂志》 2023年第7期154-156,共3页
目的分析磁共振三维快速自旋回波短时翻转恢复序列成像(3D STIR SPACE)增强序列在腰骶神经根评估中应用价值。方法选取本院2019年2月至2022年2月因腰椎疼痛入院者51例,最终纳入存在腰骶神经根压迫者42例。42例患者均进行MRI平扫+增强检... 目的分析磁共振三维快速自旋回波短时翻转恢复序列成像(3D STIR SPACE)增强序列在腰骶神经根评估中应用价值。方法选取本院2019年2月至2022年2月因腰椎疼痛入院者51例,最终纳入存在腰骶神经根压迫者42例。42例患者均进行MRI平扫+增强检查,在注射GD-DTPA对比剂前、后均进行1次冠状位3D STIR SPACE序列扫描。由两名诊断医师采用“双盲法”阅片,使用4等级法评估3D STIR SPACE序列平扫及增强的图像质量,于同一断层内测量2组图像神经根信号强度(SI神经根)、腰大肌信号强度(SI肌肉)、肾脏信号强度(SI肾脏),并计算神经根/腰大肌信号强度比(SI神经/肌肉)。通过SPSS 20.0软件分析获取的数据,使用独立样本t检验评估2组神经根形态显示及背景抑制情况,应用Kappa检验评价两种方法的一致性。结果3D STIR SPACE序列扫描的图像质量评分中,3D STIR SPACE增强序列神经根显示、背景抑制得分均明显高于3D STIR SPACE平扫序列,差异有统计学意义(P<0.05)。3D STIR SPACE增强序列SI神经根、SI神经/肌肉比值信号均明显低于3D STIR SPACE平扫序列,SI肌肉、SI肾脏信号强度高于3D STIR SPACE平扫序列,差异有统计学意义(P<0.05)。3D STIR SPACE增强序列对腰骶神经根压迫检出情况与手术检查一致性一般(Kappa值=0.655,P<0.001),灵敏度为88.10%(37/42)、特异度为88.89%(8/9)3DSTIR SPACE平扫序列对腰骶神经根压迫检出情况与手术检查一致性较差(Kappa值=0.249,P<0.05),灵敏度为69.05%(29/42)、特异度为66.67%(6/9)。结论磁共振3D SPACE STIR增强序列可清楚显示腰骶神经根形态及与周围组织关系,在显示神经根走势、受压中有显著优势。 展开更多
关键词 磁共振 增强 三维快速自旋回波短时翻转恢复序列 腰骶神经根
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基于PCAU-Net的快速多通道磁共振成像方法 被引量:1
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作者 施伟成 金朝阳 叶铮 《波谱学杂志》 CAS 北大核心 2023年第1期39-51,共13页
多通道磁共振成像方法采用多个接收线圈同时欠采样k空间以加快成像速度,并基于后处理算法重建图像,但在较高加速因子时,其图像重建质量仍然较差.本文提出了一种基于PCAU-Net的快速多通道磁共振成像方法,将单通道实数U型卷积神经网络拓... 多通道磁共振成像方法采用多个接收线圈同时欠采样k空间以加快成像速度,并基于后处理算法重建图像,但在较高加速因子时,其图像重建质量仍然较差.本文提出了一种基于PCAU-Net的快速多通道磁共振成像方法,将单通道实数U型卷积神经网络拓展到多通道复数卷积神经网络,设计了一种结构不对称的U型网络结构,通过在解码部分减小网络规模以降低模型的复杂度.PCAU-Net网络在跳跃连接前增加了1×1卷积,以实现跨通道信息交互.输入和输出之间利用残差连接为误差的反向传播提供捷径.实验结果表明,使用规则和随机采样模板,在不同加速因子时,相比常规的GRAPPA重建算法和SPIRiT重建方法,本文提出的PCAU-Net方法可高质量重建出磁共振复数图像,并且相比于PCU-Net方法,PCAU-Net减少了模型参数、缩短了训练时间. 展开更多
关键词 多线圈 快速磁共振成像 深度学习 复数卷积 不对称神经网络
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