脑积水的脑脊液MRI定量研究

目的　运用MRI门控电影相位对比序列 (cinePC)对脑积水的脑脊液进行定量研究。资料与方法　使用GEHorizonSigna 1.5T磁共振仪 ,采用MRIcinePC程序 ,对 19例阻塞性脑积水和 16例交通性脑积水的中脑导水管、枕大孔和C2 水平脑脊液流速、流量情况进行MRIcinePC检查。结果　交通性脑积水中脑导水管水平脑脊液流速和流量明显增快 ,与正常者进行统计有明显差异 (P <0 .0 5 ) ,向下峰速和向上峰速分别为 47.5 7± 16 .71mm/s和44 .48± 19.2 2mm/s,向下流量及向上流量明显增大为 3.142± 1.0 5 5ml/s及 3.143± 1.0 5 5ml/s ,净流量为 0± 0 .0 0 3ml/s ;而枕大孔向下峰速和向上峰速分别为 1.37± 0 .44mm/s和 1.33± 0 .41mm/s,向下流量及向上流量分别为 0 .35 1±0 .12 5ml/s及 0 .35 0± 0 .12 1ml/s ,净流量 0 .0 0 1± 0 .0 0 7ml/s;C2 水平脑脊液向下峰速和向上峰速分别为 2 .41±1.2 7mm/s和 2 .95± 1.15mm/s,向下流量及向上流量分别为 0 .5 2 1± 0 .2 14ml/s和 0 .5 19± 0 .2 14ml/s,净流量为0 .0 0 2± 0 .0 0 3ml/s。阻塞性脑积水在MRI上于通路阻塞处未见明显脑脊液流动 ,流速和流量基本为 0 ;枕大孔处向下峰速和向上峰速分别为 4.83± 2 .2 5mm/s和 4.72± 1.81mm/s,向下流量及向上流量分别为 0     

磁共振相位对比电影成像在脑积水诊断中的临床应用

目的评价磁共振相位对比电影成像（PC-MRI）技术在脑积水诊断中的临床应用价值。方法使用GE3.0 T磁共振扫描仪,采用PC-MRI程序检查,对我院收治的20例交通性脑积水及25例梗阻性脑积水患者及48名同期在我院体检的志愿者的中脑导水管水平脑脊液流速、流量进行检测,比较2组脑脊液相关力学数据基本情况。结果 交通性脑积水中脑导水管水平脑脊液在不同阶段所引起的反应存在着一定的差异,其中在收缩期与舒张期分别表现为向下、向上峰速,而且均大幅增加了其流量;梗阻性脑积水中脑导水管水平脑脊液在不同阶段所引起的反应也存在一定的差异,其中在收缩期与舒张期分别表现为向下、向上峰速,而且在流量方面都出现大幅降低的现象。相较于健康人进行统计有明显差异（P<0.05）,健康人（对照组）脑脊液流动曲线呈U形、倒U形,正弦波形,曲线光滑,而脑积水组脑脊液流动曲线呈锯齿状,无规则,或呈直线。结论 磁共振相位对比电影成像能无创检测脑脊液流速、流量和方向,可鉴别脑积水类型,为临床治疗提供方向。     

MRI动态增强扫描在脑小血管病诊断中的应用进展

脑小血管病(cSVD)是一种影响大脑小动脉、微动脉、微静脉和毛细血管的脑部血管疾病,其神经影像学特征包括近期皮质下小梗死、腔隙性梗死、白质高信号(WMH)、血管周围间隙扩大(EPVS)、脑微出血(CMBs)和脑萎缩.MRI动态增强扫描是目前研究cSVD血-脑脊液屏障渗透率最常用的方法.现就MRI动态增强扫描在cSVD方...     

自发性正常压力脑积水的MRI研究进展

自发性正常压力脑积水是一种以步态不稳、进行性认知功能障碍、尿失禁为主要临床表现,脑脊液压力正常的脑积水类型。发病原因不明,但部分病人的临床症状在脑脊液分流术后得到改善。近年来MRI新技术如体积测量、相位对比电影法、扩散张量成像(DTI)、磁共振波谱(MRS)、磁共振弹性成像(MRE)等在自发性正常压力脑积水相关研究中有较多的应用,就MRI技术在自发性正常压力脑积水的诊断、鉴别诊断、分流手术结果的预测、病因探讨方面的研究进展进行综述。     

交通性脑积水脑室分流前后的脑脊液MRI定量研究

目的运用MRI cine PC定量研究交通性脑积水脑室分流前后的脑脊液流动情况.材料和方法在1.5T GEHo rizon Signa磁共振机器上利用MRI cine PC程序,在以前实验所得的液体流速与信号强度关系公式的基础上,对16例交通性脑积水的中脑导水管、枕大孔和C2水平脑脊液流速、流量情况进行MRI cine PC检查(1.5TGE Horizon Signa),并对其中10例交通性脑积水脑室引流后的中脑导水管和枕大孔处脑脊液的流速和流量同样进行测量,并与术前进行比较.同时作为对照,对31例正常志愿者颅内中脑导水管、枕大孔和C2水平的脑脊液流速和流量进行测定.结果交通性脑积水中脑导水管水平脑脊液流速和流量明显增快,与正常者进行统计有明显差异(P＜0.05),向下峰速和向上峰速分别为47.57±16.71mm/s和44.48±19.22mm/s,向下流量及向上流量明显增大为3.142±1.055ml/s及3.143±1.055ml/s;脑脊液净流量为0±0.003ml/s.而枕大孔向下峰速和向上峰速分别为1.37±0.44mm/s和1.33±0.41mm/s,向下流量及向上流量分别为0.351±0.125ml/s及0.350±0.121ml/s;脑脊液净流量为0.001±0.007ml/s.C2水平脑脊液向下峰速和向上峰速分别为2.41±1.27mm/s和2.95±1.15mm/s,向下流量及向上流量分别为0.521±0.214ml/s和0.519±0.214ml/s;脑脊液净流量为0.002±0.003ml/s.其中10例交通性脑积水经VP手术前后对比分析,发现术后症状改善明显者中脑导水管脑脊液流速和向上、下的流量均较术前明显减少(P＜0.05).结论MRI cine PC对脑脊液(CSF)流动的研究具有非损伤性和对脑脊液流动敏感的特点,是一种优于其他方法的研究CSF流动的重要方法,同时对脑脊液循环障碍疾病的脑脊液流动情况也能定量测定,对VP分流前后的交通性脑积水的脑脊液流速、流量和方向的确定,对估计其术后效果具有重要意义.     

功能磁共振成像技术在脑小血管病中的应用研究进展

脑小血管病(CSVD)作为一种全脑性的临床、神经影像及病理学综合征,被认为是导致痴呆、认知衰退、步态障碍、情绪障碍和中风的主要血管因素,因此早期诊断十分关键。功能磁共振成像技术的快速发展,有望为CSVD的早期诊断及发病机制的研究提供更多可能。本文对这些技术在CSVD中的应用研究进行系统综述。     

MRI高分辨力黑水成像对交通性脑积水中脑导水管通畅性的诊断价值

目的 :通过高分辨力黑水序列判断交通性脑积水患者中脑导水管是否通畅。方法 :选择54例交通性脑积水患者,行矢状位黑水序列和轴位脑脊液相位对比电影(PC cine)序列。扫描结束后,由2位高年资医师行双盲法判读;先根据黑水CUBE T_2判断中脑导水管是否流通,根据图像特点诊断中脑导水管流通性。后使用PC cine序列测量中脑导水管处流速,并以此为中脑导水管通畅与否标准,与黑水CUBE T_2序列进行对照。比较交通性脑积水和正常对照组中脑导水管脑脊液流速和流量。结果:交通性脑积水患者中脑导水管流速和流量明显大于正常志愿者(均P0.05)。2名医师根据黑水序列诊断交通性脑积水患者中脑导水管畅通性比较差异无统计学意义(P=0.25)。ROC曲线下面积为0.956(95%CI 0.883~0.990),AUC0.9,说明对交通性脑积水的诊断价值较高。结论:MRI黑水序列无创、简便易行,能充分显示交通性脑积水患者脑脊液流动路线,可用于诊断交通性脑积水患者中脑导水管通畅性。     

PC-MRI技术在脑脊液循环中的应用

目的：分析MRI相位对比成像（PC-MRI）在中脑导水管区脑脊液检测时的流动曲线,以及流速编码（VENC）、导水管位置、ROI面积3个因素对结果的影响。方法：纳入30例志愿者,10例（第1组）定位导水管中段,VENC=5、10、20、70 cm/s扫描4次,ROI=0.03 cm²;10例（第2组）VENC=20 cm/s、于导水管上口、中段、下口扫描3次,ROI=0.03 cm²;10例（第3组）定位导水管中段、VENC=20 cm/s扫描,绘制ROI=0.01、0.02、0.03、0.04 cm² 4次。ROI绘制后系统自动生成流动曲线和各流动参数。结果：①流动曲线呈正、余弦波和“U”型波多种形态。②第1组VENC=5 cm/s均见混淆伪影、流动曲线呈无规律波浪状,与VENC=10、20、70 cm/s时的峰值流速、绝对每博输出量（ASV）差异均有统计学意义（均P<0.05）;VENC=10、20、70 cm/s时无混淆伪影,流动曲线呈规律性,各测量结果差异均无统计学意义（均P>0.05）。③第2组导水管不同部位所测流动参数,差异均无统计学意义（均P>0.05）。④第3组ASV随ROI增大而增加,差异有统计学意义（P<0.05）;不同ROI时的峰值流速、平均流速及回返系数差异均无统计学意义（均P>0.05）。结论：①导水管区脑脊液流动曲线形态多样,但均反映双向往复波动式流动,延长诸波形具有一致性。②VENC=5 cm/s取值过低,70 cm/s取值略高,10～20 cm/s较合理;③扫描导水管不同部位对测量结果无影响;④ROI面积与ASV及回返系数呈正比,对峰值流速、平均流速无影响。     

MR流体定量技术在脑脊液循环障碍疾病诊断中的应用

目的:无创性定量研究脑脊液循环改变及其临床意义。材料和方法:应用MR相位对比电影法,测定了15例正常志愿者,67例脑脊液循环障碍患者(交通性脑积水32例、阻塞性脑积水31例、Chiaril畸形4例)以及15例脑萎缩患者的中脑导水管、C2水平及部分第三脑室底部造瘘口水平的脑脊液动力学指标(峰值流速、流量及CSF流动波型)。结果:(1)正常志愿组中脑导水管脑脊液流动在一个心动周期内均表现为双向流动,即收缩期向下流动和舒张期向上流动,向下及向上峰速分别为12.60±4.42mm/s和10.10±3.58mm/s;(2)交通性脑积水组脑脊液循环表现为高动力学改变,向下及向上峰速分别为26.60±9.06mm/s和22.61±7.92mm/s,与正常志愿组比较有显著差异(P<0.05)。脑积水分流前后比较导水管循环减慢者提示有效;阻塞性脑积水组表现为低动力学或流动波消失,2例行第三脑室造瘘者导水管流动不规则,造瘘口出现上下流动现象;Chiaril畸形组C2水平脊髓后间隙缩小,流动减慢,脊髓前间隙增宽,1例合并空洞者囊腔内出现高动力学改变;(3)脑萎缩组表现为低动力学改变,向下及向上峰速分别为11.71±4.75mm/s和8.54±3.08mm/s,与正常志愿组、交通性脑积水组比较均有显著差异(P<0.05)。结论:MR相位对比电影法可有效评价脑脊液循环动力学改变,可丰富脑脊液循环     

MRI and hydrocephalus in childhood

Summary In six young patients presenting with raised intracranial pressure during the period of a year, CT revealed the presence of hydrocephalus, but not the cause. Magnetic Resonance Imaging not only shwed the site and nature of the obstructing lesion, but also detected additional clinically silent spinal cord tumors in five of the patients. The place of MRI in the diagnosis of diseases involving the region of the cranio-cervical junction and in the elucidation of unexplained hydrocephalus is considered.     

Functional analysis of third ventriculostomy patency with phase-contrast MRI velocity measurements

Our purpose was to explore the utility of cine phase-contrast MRI velocity measurements in determining the functional status of third ventriculostomies, and to correlate the quantitative velocity data with clinical follow-up. We examined six patients with third ventriculostomies and 12 normal subjects by phase-contrast MRI. The maximum craniocaudal to maximum caudocranial velocity range was measured at regions of interest near the third ventricular floor, and in cerebrospinal fluid anterior to the upper pons and spinal cord on midline sagittal images. Ratios of the velocities of both the third ventricle and prepontine space to the space anterior to the spinal cord were obtained. The velocities near the third ventricular floor and in the pontine cistern were significantly higher in patients than in normal subjects, but the velocity anterior to the spinal cord was similar between the groups. The velocity ratios, used to normalize individual differences, were also higher in patients than in controls. Two patients had lower velocity ratios than their fellows at the third ventricular floor and in the pontine cistern; one required a shunt 11 months later, while in the other, who had a third ventricular/thalamic tumor, the lower values probably reflect distortion of the third ventricular floor. We conclude that phase-contrast MR velocity measurements, specifically the velocity ratio between the high pontine cistern and the space anterior to the spinal cord, can help determine the functional status of third ventriculostomies. Received: 30 October 1995 Accepted: 28 March 1996     

脑膜型囊虫病的磁共振成像诊断

目的探讨磁共振成像(MRI)对脑膜型囊虫病的诊断价值。资料与方法回顾性分析经临床证实的21例脑膜型囊虫病的MRI表现特点。2l例均行MR平扫,7例同时行MR增强扫描。结果21例脑膜型囊虫病中,单纯性脑膜型囊虫8例(38．1％),混合型13例(61．9％)。其中19例脑膜型囊虫多发,呈葡萄串状生长,2例单发,呈分叶状。囊虫发生于外侧裂9例,鞍上池6例,小脑桥脑角池4例,前纵裂池1例,同时发生于鞍上池与小脑桥脑角池1例。囊虫囊泡在T1WI上等于或稍高于脑脊液(CSF)信号,T2WI上等于CSF信号。囊泡壁在轴面T1WI上显示较为清楚,一般呈边缘光滑的细线样稍高信号影,增强后轻度强化;所有脑膜型囊虫内均未见头节显示。结论MRI是诊断脑膜型囊虫病的首选影像学检查方法。     

Investigation of hydrocephalus with three-dimensional constructive interference in steady state MRI

We report four patients with various types of hydrocephalus in whom constructive interference in steady state (CISS) MRI disclosed the cause of the hydrocephalus. The imaging clearly delineated an abnormal contour of the ventricular system and intraventricular septa, essential information for surgical planning, including endoscopic surgery. Postoperative CISS images were useful for showing not only regression of hydrocephalus but also the patency of small fenestrations. Received: 10 May 1999/Accepted: 7 January 2000     

Frequency analyses of CSF flow on cine MRI in normal pressure hydrocephalus

Our objective was to clarify intracranial cerebrospinal fluid (CSF) flow dynamics in normal-pressure hydrocephalus (NPH). Frequency analyses of CSF flow measured with phase-contrast cine MRI were performed. The CSF flow spectra in the aqueduct were determined in patients (n=51) with NPH, brain atrophy or asymptomatic ventricular dilation (VD), and in healthy volunteers (control group; n=25). The changes in CSF flow spectra were also analyzed after intravenous injection of acetazolamide. Moreover, a phase transfer function (PTF) calculated from the spectra of the driving vascular pulsation and CSF flow in the aqueduct were assessed. These values were compared with the pressure volume response (PVR). The amplitude in the NPH group was significantly larger than that in the VD or control group because of a decrease in compliance. The phase in the NPH group was significantly different from that in either the VD or the control group, but no difference was found between the VD and control groups. The amplitude increased in all groups after acetazolamide injection. The PTF in the NPH group was significantly larger than in the control group, and a positive correlation was noted between PTF and PVR. Frequency analyses of CSF flow measured by cine MRI make it possible to noninvasively obtain a more detailed picture of the pathophysiology of NPH. Electronic Publication     

烟雾病的磁共振成像诊断

目的：回顾分析８例烟雾病的磁共振成像表现，探讨磁共振成像对烟雾病的诊断价值。方法：８例烟雾病中男女各４例。年龄４～４９岁，平均２０．４岁。磁共振成像应用Ｓｉｅｍｅｎｓ１．０ＴＭＲ系统和头表面线圈。均有ＳＥ序列Ｔ１ＷＩ和Ｔ２ＷＩ，７例有三维时间飞跃法磁共振血管造影（３Ｄ－ＴＯＦＭＲＡ），１例有ＤＳＡ。结果：ＳＥ序列ＭＲＩ均见丘脑－基底节区（单侧２例，双侧６例）有扩张的烟雾血管，其中以Ｔ１ＷＩ显示更为清楚直观。７例３Ｄ－ＴＯＦＭＲＡ和１例ＤＳＡ均见ＩＣＡ上端、ＭＣＡ和ＡＣＡ近端闭塞以及丘脑－基底节区的烟雾血管。这些病理血管分布侧别与ＳＥ序列磁共振成像所见一致。结论：ＳＥ序列磁共振成像和３Ｄ－ＴＯＦＭＲＡ是诊断烟雾病的有效方法。Ｔ１ＷＩ显示丘脑－基底节区烟雾血管优于Ｔ２ＷＩ。３Ｄ－ＴＯＦＭＲＡ尚适用于烟雾病血管旁路术后随诊及其高危人群普查。     

侧脑室内室管膜下瘤的MRI诊断

目的 研究侧脑室内室管膜下瘤的MRI表现,以提高对该病的神经放射学认识。资料与方法 搜集8例经手术病理证实的侧脑室内室管膜下瘤,男5例,女3例,发病年龄16-47岁,平均32．9岁。着重分析肿瘤的好发年龄、部位,MRI信号特点,肿瘤增强情况。结果 左侧脑室内4例,右侧脑室内3例,双侧脑室内1例,除1例位于双侧脑室体部及三角区外,其余病例皆发生于侧脑室室问孔附近,肿瘤漂浮在侧脑室中。肿瘤最大直径4cm,最小1cm。T2WI肿瘤呈均匀高信号;T1WI肿瘤呈等、低信号,肿瘤内部可见小囊状低信号区。增强扫描,肿瘤无强化或有轻微强化。结论 室管膜下瘤的MRI表现具有特征性,术前MRI检查可以对其作出明确的定位定性诊断。     

Constructive interference in steady-state 3D Fourier-transform MRI in the management of hydrocephalus and third ventriculostomy

We describe the use of three-dimensional Fourier transform constructive imaging in the steady state (CISS) MRI in the assessment of patients with hydrocephalus. We have found it of value both as a diagnostic investigation and in the follow-up of patients treated by third ventriculostomy. Received: 30 September 1997 Accepted: 15 July 1998     

Spatial data analysis in the quantitative assessment of cerebral white matter pathology on MRI in HIV infection

This study was carried out using MRI (proton density-and T2-weighted) on 16 HIV-negative controls, 9 symptom-free HIV-positive patients and 25 with CDC IV HIV disease. The studies from this last group had previously been allocated by a radiologist to the following categories: 8 with focal mass lesions and normal-appearing white matter; 9 with diffuse encephalopathy (high signal on T2-weighted images, affecting most or all of the white matter) and 8 with patchy encephalopathy (high signal affecting only one or two areas within the white matter). Moran'sI, a statistic of spatial autocorrelation, was calculated for the grey-scale values of a sampled pixel array from a central white matter region of each of the images. All values of Moran'sI calculated in this study showed a large positive excess over the expected value under randomisation, indicating highly significant positive autocorrelation in the spatial arrangement of the grey-scale values. On T2-weighted images a statistically significant increase in the mean value of Moran'sI, compared with controls, was found in the diffuse encephalopathy group, indicating that quantifiable changes in the spatial autocorrelation of pixel data can be related to recognised qualitative changes in the appearance of white matter in subjects with HIV disease. A lesser, but significant, rise in the mean value of Moran'sI was also found in the focal mass lesion group, suggesting that changes in spatial autocorrelation may indicate pathological change in advance of qualitative MRI changes.     

Cavernous dilatation of mesencephalic Virchow-Robin spaces with obstructive hydrocephalus

We describe two patients with mild ventricular dilatation, shown to have cystic spaces in the midbrain, which we interpreted as greatly enlarged Virchow-Robin spaces. We discuss the pathophysiology and the possible relations to the mild hydrocephalus. Received: 1 September 1999/Accepted: 22 October 1999