磁共振成像新技术在诊断卒中后抑郁方面的应用

当前卒中后抑郁（post-stroke depression,PSD）作为脑卒中后常见的并发症越来越受到人们的关注,但是 PSD 的发病机制、病理定位、诊断标准等尚不明确,PSD 患者极易被漏诊或误诊。近年来MRI 技术飞速发展产生了一系列新的成像技术,它们可以从血流灌注、生理结构、生物代谢等方面反映大脑功能和结构的变化,并且具有无创性、无放射性、时间空间分辨率高、脑功能区定位准确等特点,在PSD的发病机制、病理定位、早期诊断及疗效评价等方面应用潜力巨大。     

近红外脑功能成像对卒中后抑郁神经机制的研究北大核心CSCD

目的观察卒中后抑郁(PSD)患者在认知加工期间前额叶氧合血红蛋白(Oxy-Hb)相对浓度变化值,初步探讨PSD的神经机制和工作记忆功能变化。方法 2017年2月至8月,20例PSD患者(PSD组)及20例卒中非抑郁患者(对照组),应用NIRSport便携式近红外脑功能成像系统,分别采用情绪面孔性别判断任务和"1-back"工作记忆任务,观察前额叶Oxy-Hb相对浓度变化值。结果在负性情绪面孔图片呈现后,PSD组前额叶Oxy-Hb相对浓度变化值显著低于对照组(t=3.872,P<0.001)。在"1-back"工作记忆任务时,PSD组左侧前额叶Oxy-Hb相对浓度变化值低于对照组(t=2.475,P=0.018),两组右侧前额叶Oxy-Hb相对浓度变化值无显著性差异(t=1.773,P=0.084)。结论 PSD患者在负性情绪面孔图片呈现后,前额叶激活程度降低,并且左侧前额叶工作记忆功能受损,PSD患者前额叶有氧代谢功能失调。     

基于多模态磁共振成像探讨针刺治疗卒中后失语症的研究进展

卒中后失语症（post-stroke aphasia, PSA）是指因脑血管或言语中枢神经功能紊乱引起的后天性语言功能障碍。针刺治疗PSA已取得较好的临床疗效,但其作用机制尚未明确。近年来,多模态MRI飞速发展,此项技术具有无辐射、多参数、多序列成像等优点,已被众多学者应用于PSA中枢效应机制研究。本研究基于功能MRI、弥散张量成像、结构性MRI、磁共振波谱成像等多模态成像技术,从脑功能、脑结构及脑代谢等角度探讨了针刺对PSA患者中枢效应机制,旨在为针刺治疗PSA临床个体化诊疗方案提供新方向,为研究针刺治疗PSA的潜在机制提供新思路。     

基于头针的音乐疗法对卒中后抑郁疗效的静息态功能磁共振观察

采用静息态功能磁共振(rs-fMRI)观察音乐疗法结合头针对卒中后抑郁(PSD)患者脑功能的影响。     

近红外脑功能成像对卒中后抑郁神经机制的研究

目的观察卒中后抑郁(PSD)患者在认知加工期间前额叶氧合血红蛋白(Oxy-Hb)相对浓度变化值,初步探讨PSD的神经机制和工作记忆功能变化。方法 2017年2月至8月,20例PSD患者(PSD组)及20例卒中非抑郁患者(对照组),应用NIRSport便携式近红外脑功能成像系统,分别采用情绪面孔性别判断任务和"1-back"工作记忆任务,观察前额叶Oxy-Hb相对浓度变化值。结果在负性情绪面孔图片呈现后,PSD组前额叶Oxy-Hb相对浓度变化值显著低于对照组(t=3.872,P0.001)。在"1-back"工作记忆任务时,PSD组左侧前额叶Oxy-Hb相对浓度变化值低于对照组(t=2.475,P=0.018),两组右侧前额叶Oxy-Hb相对浓度变化值无显著性差异(t=1.773,P=0.084)。结论 PSD患者在负性情绪面孔图片呈现后,前额叶激活程度降低,并且左侧前额叶工作记忆功能受损,PSD患者前额叶有氧代谢功能失调。     

重复经颅磁刺激治疗卒中后吞咽困难的相关临床研究进展

卒中后吞咽困难（PSD）是脑卒中后常见的并发症,考虑到PSD的发病率及其造成的严重后果,PSD患者吞咽功能有效、快速的恢复极其重要。近年来重复经颅磁刺激（rTMS）技术兴起,各项研究层出不穷,为PSD的治疗提供了新的方法手段。本文从机制探讨和临床应用两大方面对PSD的发生机制、PSD恢复的相关机制、rTMS相关参数的设定、rTMS治疗PSD相关临床实践方案的选择及疗效等进行综述,以期对未来的研究方向提供一定思路。     

脑卒中后抑郁与病变部位的相关性分析

目的探讨脑卒中患者卒中后抑郁(PSD)与卒中部位的关系。方法对187例脑卒中患者行头颅MRI或头颅CT检查以明确诊断,发病后6周内对患者进行抑郁状态评定,分析PSD的发生与发病部位的关系。结果 63人确诊为PSD,左侧额叶脑卒中患者PSD的发生率高于非左侧额叶脑卒中患者(P<0.05)。PSD在脑梗死和脑出血、单病灶和多病灶、前循环和后循环、左侧和右侧脑卒中之间的发病率差异无统计学意义(P>0.05)。结论脑卒中患者PSD的发生与左侧额叶卒中有显著相关性。     

深部脑磁刺激改善大鼠卒中后抑郁样行为

目的：探讨深部脑磁刺激（DMS）对卒中后抑郁（PSD）模型大鼠抑郁样行为的治疗作用及其可能机制。方法：糖水偏好实验和旷场实验筛选42只正常的雄性成年SD大鼠,随机分为假手术组（Sham组,n=6）、卒中组（Stroke组,n=12）、卒中后抑郁组（PSD组,n=12）、深部脑磁刺激治疗组[（PSD+DMS）组,n=12];后3组颈总动脉线栓再灌注法构建脑缺血模型;假手术组只分离颈总动脉不结扎;PSD组和（PSD+DMS）组接受3周慢性温和应激制备PSD模型;（PSD+DMS）组每天接受40 min的40 Hz深部脑磁刺激治疗,共2周。旷场实验检测各组大鼠运动功能和焦虑样行为;糖水偏好实验检测各组大鼠快感缺失抑郁样行为;免疫荧光染色检测各组大鼠前额叶小胶质细胞激活标志物Iba-1的表达水平;蛋白质免疫印迹技术检测各组大鼠前额叶小胶质细胞激活阳性蛋白CD11b及炎性因子IL-1β和TNF-α的表达。结果：（PSD+DMS）组大鼠抑郁样行为较PSD组明显好转。卒中组大鼠前额叶小胶质细胞激活增加,炎性因子IL-1β和TNF-α的蛋白表达升高,PSD组大鼠前额叶小胶质细胞激活进一步增加,炎性因子...     

卒中后不同时期并发抑郁的相关危险因素

卒中后抑郁(PSD)是脑卒中后常见的并发症之一.目前关于其发病率的研究并不一致.Hackett等[1]对1977～2002年符合纳入标准的全部51项前瞻性研究进行了荟萃分析,结果发现,卒中后1个月内、1～6个月和6个月以上患者中PSD的发病率分别为32%、34%和34%,总患病率为33%.PSD的产生将严重影响患者肢体功能的康复,降低患者的生活质量,而且还会增加卒中的病死率[2].因此人们越来越重视PSD的研究.但目前PSD发病机制仍不明确,相关危险因素的研究也存在较大争议.有研究认为,在卒中后不同时期PSD的发病率有所不同,相应的不同时期并发PSD的危险因素也并不一致,本研究就卒中后不同时期并发PSD的相关危险因素进行简要综述.     

弥散张量成像技术在卒中后抑郁疾病中的应用进展

脑卒中是严重危害人民群众生命安全的疾病，位居我国致残率和致死率病因的首位，卒中后抑郁（PSD）是脑卒中后最为常见的大脑功能失调状态，其加剧卒中后的认知功能障碍，延缓卒中后的康复进程，增加卒中的致残率、病死率与复发率。弥散张量成像技术可以显示活体脑白质结构，被广泛应用于脑疾病的发病机制研究，并逐渐成为疗效评价的指标。本文综述了弥散张量成像技术在卒中后抑郁疾病中的应用情况，主要从卒中后抑郁的危险因素、发病机制假说、生物标记物方面进行概括分析，并阐述了基于弥散张量成像研究的卒中后抑郁的风险因素，旨在探讨其研究现状与应用进展。      

卒中患者吞咽评估影像学研究进展

吞咽障碍是卒中患者不良结局的独立危险因素。影像学检查是吞咽障碍的主要检查和评价方法,可明确造成吞咽障碍的病变部位,指导治疗。深入了解吞咽障碍的影像学评估方法,将康复护理特色融入吞咽障碍的多学科协作诊疗模式中,有助于减少脑卒中患者并发症、提高脑卒中患者护理效果。视频透视吞咽检查是检查吞咽功能最常用的方法,是吞咽障碍临床评估的“金标准”;超声检查作为辅助检查手段,用于评估吞咽障碍患者的吞咽功能;CT具有良好的空间和时间分辨率,可三维动态显示食团和吞咽器官的运动;MRI成像可显示吞咽障碍的病灶和相关的脑功能网络。这些影像学技术可为吞咽障碍的康复护理提供依据。      

Magnetic resonance imaging of cerebral hemorrhagic stroke

Despite a traditional perception of reliance on computed tomography and lack of acceptance of magnetic resonance imaging (MRI) for detecting acute hemorrhage, MRI appears to be used increasingly in hemorrhagic stroke. This review addresses the MRI findings of acute hemorrhagic stroke obtained using relatively new imaging techniques. These new techniques have resulted in more acute stroke patients undergoing MRI examination. New information about the frequency and appearance of hemorrhage is emerging: for example, approximately 15-26% of cases of acute cerebral infarctions appear to be complicated by intracerebral hemorrhage. The MRI appearances of hemorrhagic transformation of ischemic infarction, as well as acute hypertensive intracerebral hemorrhage, are discussed based on clinical, biochemical, and technical aspects.     

急性卒中后抑郁与病灶部位神经功能缺损评分及事件相关电位P300的相关性分析

目的 研究急性卒中后抑郁(PSD)与病变部位、神经功能缺损评分(NIHSS)及事件相关电位P300的相关性.方法 采用汉密尔顿抑郁量表(HAMD)评定, 将78例首次脑卒中患者分为PSD组和非PSD组.所有患者在发病3 d内进行颅脑CT或MRI检查,2周时进行HAMD、NIHSS评分及P300检测.结果 78例急性脑卒中患者中发生PSD 32例,发生率41.03%,且其发生与病灶部位及NIHSS评分有关,病灶位于额叶的发生率明显高于基底节、顶枕叶及小脑 (P<0.05);PSD组NIHSS评分明显高于非PSD组(P<0.01);与非PSD组相比,PSD组的P300潜伏期显著延长(P<0.01),波幅显著降低(P<0.01).结论 病灶位于额叶的卒中更可能导致 PSD;神经缺损严重的患者患PSD的机率更大,而早期的P300检测可以提高对PSD的识别,有利于临床上对PSD进行早期干预,以利于脑卒中的康复.     

Modern imaging of the infarct core and the ischemic penumbra in acute stroke patients: CT versus MRI

Thrombolysis has become an approved therapy for acute stroke. However, many stroke patients do not benefit from such treatment, since the presently used criteria are very restrictive, notably with respect to the accepted time window. Even so, a significant rate of intracranial hemorrhage still occurs. Conventional cerebral computed tomography (CT) without contrast has been proposed as a selection tool for acute stroke patients. However, more-modern MRI and CT techniques, referred to as diffusion- and perfusion-weighted imaging and perfusion-CT, have been introduced, which afford a comprehensive noninvasive survey of acute stroke patients as soon as their emergency admission, with accurate demonstration of the site of arterial occlusion and its hemodynamic and pathophysiological repercussions for the brain parenchyma. The objective of this article is to present the advantages and drawbacks of CT and MRI in the evaluation of acute stroke patients.     

Magnetic resonance imaging in acute stroke: clinical perspective

The efficacy of intravenous (i.v.) and intra-arterial (i.a.) thrombolysis for hyperacute stroke has made "brain attack" a treatable emergency. The addition of ultrafast magnetic resonance imaging (MRI) to acute stroke investigation has both increased our knowledge of acute stroke pathophysiology and brought a tool to study how to best select patients for thrombolytic therapy. MR offers the three essential components: vascular lesion identification, delineation of injured brain tissue, and map of ischemic brain. MR angiography can demonstrate the site of major cerebral artery occlusion, providing a means to screen for i.a. thrombolysis. Diffusion-weighted imaging (DWI) is capable of showing acute ischemic injury within minutes of symptom onset. Perfusion-weighted imaging (PWI) shows the total area of acute ischemia, more accurately reflecting the extent of neurological dysfunction. Combining DWI and PWI immediately gives information that bears on how much tissue is injured (DWI) and how much tissue is functionally inactive but still viable (ischemic on PWI but still normal on DWI). A number of important questions remain, but current knowledge of natural history of stroke with MRI has provided a framework for comparing new therapeutic interventions. Ideally, patient treatment in the future will be tailored not to a fixed time window but to the physiological state of the ischemic tissue as defined by MRI.     

缺血性卒中后抑郁患者静息状态下默认网络功能连接的研究

目的利用静息态功能磁共振成像(resting-state functional magnetic r e s o n a n c e i m a g i n g,r s-f M R I)技术,研究缺血性卒中后抑郁(p o s t s t r o k e depression,PSD)患者静息状态下默认网络(default mode network,DMN)功能连接的变化。材料与方法选取13例发病在两周内、汉密尔顿抑郁量表(hamilton depression scale,HAMD)评分7分且为首发抑郁的PSD患者,同时选择13名正常被试作为对照组(control)分别进行静息态f MRI扫描。分别选取双侧楔前叶作为感兴趣区(region of interest,ROI),计算并比较两组被试默认网络功能连接的变化。结果与正常被试相比,PSD患者双侧顶下小叶、双侧额颞叶与右侧楔前叶功能连接减低;右侧顶下小叶、双侧额颞叶与左侧楔前叶功能连接减低,而未发现功能连接显著增高的脑区。结论默认网络功能连接的变化可能与卒中后抑郁的发生具有相关性。     

Applications of Dynamic Susceptibility Contrast Magnetic Resonance Imaging in Neuropsychiatry

Functional neuroimaging has assumed an important role in the cognitive and clinical neurosciences. Recently, substantial progress has been made toward developing functional magnetic resonance imaging techniques for the examination of cerebral hemodynamic changes that accompany brain function and toward earlier and better diagnosis of brain disease. Dynamic susceptibility contrast (DSC) MRI offers unique information about cerebral hemodynamics both at rest and in response to brain activation. We review the clinical applications of DSC MRI and present our experience with this modality in the evaluation of patients with neuropsychiatric disorders. Our experience suggests that DSC MRI may afford new insights into the diagnosis and treatment of cognitive disorders.     

Diffusion, confusion and functional MRI

Diffusion MRI has been introduced in 1985 and has had a very successful life on its own. While it has become a standard for imaging stroke and white matter disorders, the borders between diffusion MRI and the general field of fMRI have always remained fuzzy. First, diffusion MRI has been used to obtain images of brain function, based on the idea that diffusion MRI could also be made sensitive to blood flow, through the intravoxel incoherent motion (IVIM) concept. Second, the IVIM concept helped better understand the contribution from different vasculature components to the BOLD fMRI signal. Third, it has been shown recently that a genuine fMRI signal can be obtained with diffusion MRI. This "DfMRI" signal is notably different from the BOLD fMRI signal, especially for its much faster response to brain activation both at onset and offset, which points out to structural changes in the neural tissues, perhaps such as cell swelling, occurring in activated neural tissue. This short article reviews the major steps which have paved the way for this exciting development, underlying how technical progress with MRI equipment has each time been instrumental to expand the horizon of diffusion MRI toward the field of fMRI.     

Imaging-based treatment selection for intravenous and intra-arterial stroke therapies: a comprehensive review

Reperfusion therapy is the only approved treatment for acute ischemic stroke. The current approach to patient selection is primarily based on the time from stroke symptom onset. However, this algorithm sharply restricts the eligible patient population, and neglects large variations in collateral circulation that ultimately determine the therapeutic time window in individual patients. Time alone is unlikely to remain the dominant parameter. Alternative approaches to patient selection involve advanced neuroimaging methods including MRI diffusion-weighted imaging, magnetic resonance and computed tomography perfusion imaging and noninvasive angiography that provide potentially valuable information regarding the state of the brain parenchyma and the neurovasculature. These techniques have now been used extensively, and there is emerging evidence on how specific imaging data may result in improved clinical outcomes. This article will review the major studies that have investigated the role of imaging in patient selection for both intravenous and intra-arterial therapies.