心脏MRI评估肺动脉高压患者的心功能

目的探讨心脏MRI(CMRI)评价肺动脉高压(PH)患者心室功能的临床价值。方法对30例PH患者(PH组)及30名健康志愿者(对照组)进行CMRI,分别计算右心室(RV)与左心室(LV)的舒张末期容积(EDV)、收缩末期容积(ESV)、每搏输出量(SV)、射血分数(EF)、舒张末期心肌质量(MM)等心功能参数,除EF外均经体表面积(BSA)校正,记为EDVI、ESVI、SVI、MMI。计算心室质量指数(VMI,为舒张末期RV MM与LV MM的比值)。采用两独立样本t检验分析两组参数有无差异。结果 PH组RV EDVI、ESVI及MMI均显著高于对照组(P均<0.01),RV EF显著低于对照组(P<0.01),两组RV SVI的差异无统计学意义(P>0.05)。PH组LV EDVI和SVI显著低于对照组(P均<0.05),而LV ESVI、EF及MMI与对照组的差异均无统计学意义(P均>0.05)。PH组VMI显著高于对照组(P<0.01)。PH组中23例(23/30,76.67%)患者LV舒张早期可见明显变形,其中室间隔变平10例,室间隔向左弓形突出13例。结论CMRI能够无创、准确地提供PH患者RV与LV的功能信息,对于评价PH患者心室功能具有重要价值。     

埃布斯坦畸形患者右心功能参数:超声心动图与MRI评估结果的相关性

目的 分析超声心动图与心脏MRI所获埃布斯坦畸形（EA）患者右心功能参数的相关性。方法 回顾性分析经手术证实的32例EA患者的经胸超声心动图及心脏MRI资料,观察超声心动图所获心腔大小、右心功能及应变参数与MRI所测功能右心室（fRV）射血分数（EF）的相关性。结果 MRI所测 32例EA的 fRV-EF为（23.20±7.61）%。超声心动图所获32例EA右心功能参数中,fRV面积变化分数（fRV-FAC）（r=0.347,P=0.015）与MRI fRV-EF呈低度、fRV整体纵向应变（GLS）（r=0.801,P<0.001）与MRI fRV-EF呈高度正相关,房化右心室（aRV）面积/fRV面积与MRI fRV-EF呈高度负相关（r=－0.730,P=0.007）,aRV面积/左心室面积（r=－0.450,P=0.042）及右心室前后径（r=－0.650,P=0.022）与MRI fRV-EF均呈中度负相关,左心室偏心指数（r=－0.347,P=0.049）、扩展格拉斯哥预后评分（r=－0.336,P=0.024）均与MRI fRV-EF呈低度负相关。结论 超声心动图与MRI所获EA患者右心功能参数存在相关性;其中,fRV GLS及aRV面积/fRV面积均与MRI fRV-EF呈高度正相关,对于评估EA患者右心功能具有重要价值。     

多层螺旋CT冠状动脉成像同时评价左心功能的可行性研究

目的：以磁共振为对照标准，探讨多层螺旋CT（MSCT）和MRI左心功能评价指标的相关性及MSCT冠状动脉成像所得数据用于左心功能评价的准确性。方法：临床拟诊冠心病的患者20例，男7例，女13例，均自愿参加。全部病例均行心脏MSCT和MRI检查。结果：MSCT和MRI两种方法的心功能指标无显著性差异，两种方法的心功能指标EDV、ESV、SV、EF、MM相关性高，r值=0.72~0.92。MSCT所测EDV、ESV、SV和MM值较MRI偏大，MSCT所测EF值较MRI偏小。结论：本研究显示64层MSCT在左心功能定量评价方面准确可靠，与3.0T（Tesla）磁共振比较，两种方法心功能评价指标相关性高。一次MSCT冠状动脉造影检查，可以同时评估冠状动脉狭窄情况和左心室功能。     

MRI评价胎盘功能的应用进展

近年来,MRI超快速扫描技术不断发展,部分解决了胎动伪影的难题,使MRI在胎儿及胎盘检查中的优势突显,目前已成为超声诊断胎儿及胎盘异常的有力补充。MR T2WI在观察胎盘结构方面具有明显的优势,DWI、MRS等功能成像亦可用于胎盘功能评价,多种MRI扫描技术联合应用可为临床提供更清晰、直观的影像学资料。本文主要对目前MRI评价胎盘功能的临床应用进展进行综述。     

64层螺旋CT与磁共振成像评价左心功能的比较研究

目的以磁共振为对照,应用64层螺旋CT(MSCT)定量评价左心功能,探讨MSCT成像技术和屏气法MRI电影技术心功能评价指标的相关性及MSCT在冠心病左心功能评价中的应用价值。方法临床拟诊冠心病的患者20例,均自愿参加。全部病例均行心脏MSCT和MRI检查。结果MSCT和MRI两种方法的心功能指标无显著性差异,两种方法的心功能指标舒张末期容积(EDV)、收缩末期容积(ESV)、每搏输出量(SV)、左室射血分数(EF)、心肌质量(MM)相关性高,r值=0.72~0.92。MSCT所测EDV、ESV、SV和MM值较MRI偏大,MSCT所测EF值较MRI偏小。结论本研究显示64层螺旋CT在左心功能定量评价方面准确、可靠,与3.0T磁共振两种方法各指标之间相关性高。一次MSCT冠状动脉成像检查,可以同时评估冠状动脉狭窄情况和左心室功能。     

左心功能评价影像学研究进展

随着膳食结构和健康模式的改变,人均寿命的延长,心脏疾病的社会负担正在不断加重.通过现有影像学方法,早期、无创、准确的评估心脏功能,对指导临床治疗及预后有重要意义.计算机软件和硬件技术的快速发展,使得多种影像学方法可以在获得心脏形态结构的同时,获取心室容积(Ventricular volume,VV)、射血分数(Ejection fraction,EF)等心功能指标,为临床提供更多有参考价值的诊断信息.     

超声及MRI评价右心室心肌应变的临床应用

右心室功能是多种心血管疾病的重要独立预测因子。准确评估右心室功能对临床决策至关重要。超声心动图是临床常用评价心脏结构和功能的方法。心脏MR（CMR）是评价右心室结构和功能的金标准。心肌应变能反映心肌运动功能,是评价右心室早期收缩功能障碍的敏感指标。本文对超声和CMR评价心血管疾病患者右心室心肌应变的临床应用进行综述。     

实时三维超声心动图与磁共振成像评价右心功能的对照研究

目的:以磁共振电影成像法为对照,应用实时三维超声心动图定量评价右心室功能,探讨两项技术心功能评价指标的相关性及实时三维超声心动图在右心功能评价中的应用价值.方法:30例健康成年志愿者(男16例、女14例,年龄(49±3.2)岁),全部志愿者均于24 h内行心脏实时三维超声心动图和MRI检查.行实时三维超声心动图全容积显像方式采集图像数据,并导入TomTec工作站,应用4D RV-function软件行图像后处理,构建右室三维模型并进行心功能测量.最终获取舒张末期容积(EDV)、收缩末期容积(ESV)、每搏输出量(SV)及射血分数(EF)等心功能参数.与MR多次屏气电影法测得右心室功能指标进行Pearson相关分析,并采用Bland-Altman法评价两种检查方法结果的一致性.结果:实时三维超声心动图测得的心功能指标平均EDV (143.5±23.2) mL,平均ESV (68.4±19.2) mL,SV (78.1±11.7) mL,EF (51.2±5.6)％,与MR多次屏气电影法测得的心功能指标EDV (147.5±26.8) mL(r=0.947),ESV (63.2±15.9) mL(r=0.909),SV (78.8±15.0) mL(r=0.788),EF (55.2±7.7)％(r=-0.627)均无显著性差异,显示出较高相关性.结论:本研究显示实时三维超声心动图与1.5T磁共振成像评价右心功能各指标之间相关性高,在右心功能定量评价方面准确、可靠.     

心脏MRI应变技术评估高血压患者左心室功能

目的 观察心脏MRI应变技术评估高血压患者左心室功能的可行性.方法 对88例高血压患者(高血压组)和28名健康志愿者(正常组)行心脏MR检查.将高血压组中血压140～159/90～99 mmHg者纳入Ⅰ组(32例),160～179/100～109 mmHg为Ⅱ组(28例),≥180/110 mmHg为Ⅲ组(28例).对...     

小儿肺炎左心功能评价

用肺微分阻抗血流图(DIPR)时相分析法,检测普通肺炎和肺炎合并心衰的小儿右心室收缩时间间期(RVSTI),左心室收缩时间间期(LVSTI),是了解肺炎时心血管功能状态较为实用的非创伤性方法之一,这对于观察心功能变化,探讨肺炎合并心衰的发病机理和指导治疗均具有重要的意义。     

Functional MR imaging

Functional MR (fMR) imaging offers unprecedented spatial and temporal resolution of brain cognition. The impact of this technology on neuroscience research is just now being explored. This article discusses blood oxygenation level-dependent-based fMR imaging. Topics include the origin of the MR-based signal, data acquisition and sequence dependence, and paradigm design issues--issues that need to be fully understood to properly design and interpret the fMR imaging experiment.     

Functional renal MR imaging

MR imaging is the only noninvasive test that may provide a complete picture of renal status with minimal risk to the patient, simultaneously improving diagnosis and lowering costs. This article reviews several MR renography techniques, including approaches for quantifying renal perfusion and glomerular filtration rate. Also discussed are clinical applications for the diagnosis and follow-up of renovascular disease, hydronephrosis,and renal transplant dysfunction. The article concludes with an overview of technical problems and challenges facing MR renography.     

动态增强MR成像在肿瘤血管生成功能成像中的应用

通过静脉注射细胞外对比剂(Gd-DTPA)后,磁共振成像(MRI)可以描述肿瘤的血管特征.由于不同组织对造影剂药物动力学的影响不同,因而动态增强磁共振成像(DCE-MRI)具有展示组织内在差异的功能.大量研究结果表明,DCE-MRI数据结果与肿瘤血管生成免疫组织标记物间具有相关性,可以用于监测各种肿瘤治疗方法的效果,如:放疗、化疗、激素治疗以及新的抗血管生成治疗等.本文就DCE-MRI基本方法和数据处理方法作一简要回顾.     

Functional MR imaging in pediatrics

Functional magnetic resonance (fMR) imaging can show neuronal structures underlying specific perceptual and cognitive processes. With the aid of fMR imaging, the development of brain functions can be followed, and deviation from the normal pattern can be established quickly. This article discusses the unique issues of fMR imaging in the pediatric population (e.g., the occurrence of a negative blood oxygenation-level dependent [BOLD] signal during visual stimulation in the age group in whom the synaptic density is the highest; in older children, when synaptic pruning has proceeded, the BOLD signal takes on the positive characteristics seen in adults). fMR imaging also suggests prospectively important applications in the diagnostic workup of children: an early diagnosis of functional deficit can reduce residual deficits to a minimum because remediation, such as specialized training, can be started at an early stage.     

Functional MR imaging of the lung

Recent development of MR techniques has overcome many problems, such as susceptibility artifacts or motion artifact, allowing both static and dynamic MR lung imaging and providing quantitative information of pulmonary function, including perfusion, ventilation, and respiratory motion. Dynamic contrast-enhanced MR perfusion imaging is suitable for the evaluation of angiogenesis of pulmonary solitary nodules. (129)Xe MR imaging is potentially a robust technique for the evaluation of various pulmonary function and may replace (3)He. The information provided by these new MR imaging methods is proving useful in research and in clinical applications in various lung diseases.     

Functional MR imaging of the uterus

Recent developments in MR imaging techniques have enabled the functional assessment of the uterus. Cine MR imaging is a useful tool for evaluating uterine kinematic functions derived from myometrial contractility, and for investigating the alteration of uterine contractility in a variety of conditions and gynecologic disorders. Diffusion-weighted imaging can demonstrate abnormal signal in pathologic foci based on differences in molecular diffusion, and could provide useful information in evaluating malignant conditions. Dynamic contrast-enhanced MR imaging has the potential to improve tumor detection and local staging, and quantitative information may be useful for both monitoring therapeutic effects and predicting outcome. These state-of-the-art functional MR imaging techniques are beneficial for elucidating various uterine conditions when used appropriately, and the findings further provide the basis of future MR imaging investigations.     

功能磁共振成像在视觉系统研究中的应用进展

血氧水平依赖功能磁共振成像(BOLD-fMRI)实现了对人类视觉系统相关脑区的功能定位,在视觉系统的研究中已取得重要成果.本文详细讨论了人类视觉加工的神经过程,即等级加工和平行加工理论.并就fMRI在视觉皮层定位、颜色识别、运动物体视觉感知等方面的应用作一综述.     

Functional renal MR imaging: an overview

Due to its complementary information to standard morphological imaging, functional renal magnetic resonance imaging is a rapid growing field of radiology. This pictorial essay provides a comprehensive overview of state-of-the-art functional renal imaging techniques including renal magnetic resonance angiography, first pass renal perfusion, assessment of renal function, blood-oxygen level dependent imaging of the kidneys and diffusion-weighted imaging of the kidneys including diffusion-tensor imaging of the kidneys. Basic technical concepts for all sequences are laid out. As renal perfusion imaging becomes a clinical routine examination, particular attention is given to renal perfusion measurements and the potential postprocessing approaches. Advantages and drawbacks of the published methods are illustrated. Future applications of functional renal imaging are presented. HJM and SS contributed equally.     

MR imaging evaluation of the adnexa

MR imaging has become an important tool in the evaluation of patients with adnexal disease, and its role continues to evolve. Some benign entities can be diagnosed by MR imaging with a high grade of confidence, such as teratomas, endometriomas, simple and hemorrhagic cysts, fibromas, and hydrosalpinx. In cases of malignant lesions, MR imaging may be more accurate than other modalities for lesion characterization, staging, and follow-up.     

MR imaging evaluation of the hepatic vasculature

Assessment of the hepatic vasculature is essential for tumor staging, surgical planning, and understanding of liver disease. Technological advances have made contrast-enhanced magnetic resonance (MR) imaging comparable to multidetector-row computed tomography for diagnostic vascular imaging with respect to spatial resolution. Unenhanced MR angiographic sequences enable reasonable clinical assessment of vessels without contrast agents in patients with contraindications or renal insufficiency. Furthermore, MR angiography may be used to provide directional information through manipulation of the signal intensity of flowing blood. A major limitation to consistent contrast-enhanced MR angiography is the timing of MR image acquisition with arrival of the contrast bolus in the structures of interest. In this article, the authors discuss currently available techniques for imaging of the hepatic vasculature.