亚急性联合变性的磁共振表现

目的评价磁共振成像（ＭＲＩ）对亚急性联合变性（ＳＣＤ）的诊断价值。方法对临床和实验室检查确诊的７例ＳＣＤ患者进行ＭＲＩ检查。结果有３例异常，均位于胸段脊髓，２例Ｔ２加权为片状或条状高信号区，１例胸髓变细。结论ＭＲＩ对ＳＣＤ有一定的诊断价值。     

小脑梗塞的临床及MRI诊断分析

本文报告１２例小脑梗塞的ＭＲＩ检查，并与ＣＴ和临床检查对照。讨论了其病因、分型、ＭＲＩ平扫及Ｇｄ—ＤＴＰＡ增强所见，诊断和治疗。在小脑梗塞刀性期，Ｔ１加权像（Ｔ１Ｗ１）呈等信号或稍低信号，Ｔ２Ｗ１呈高信号。Ｇｄ—ＤＴＰＡ增强扫描及复查扫描对小脑梗塞与肿瘤的鉴别有重要意义。大面积小脑梗塞如能早期确诊仍可行保守治疗。     

肝豆状核变性的脑MRI与临床表现的相关分析

目的探讨肝豆状核变性（ｈｅｐａｔｏｌｅｎｔｉｃｕｌａｒｄｅｇｅｎｅｒａｔｉｏｎ，ＨＬＤ）的脑ＭＲＩ表现特点与ＨＬＤ病程及神经体征间有无相关性，以及ＭＲＩ是否有助于ＨＬＤ的诊断。方法对１６例具有角膜Ｋ－Ｆ环阳性、锥体外系体征以及生化检验异常的ＨＬＤ患者进行了头部ＭＲＩＳＥ序列横轴面和矢状面扫描。结果异常信号多呈长Ｔ１长Ｔ２且分布广泛，对称出现，Ｔ２加权像低信号为本病较具特征性的改变，病变分布以豆状核、丘脑及脑干为显著，其分布与某些神经体征有很好的相关性，但与病程间无相关性。结论ＭＲＩ有助于ＨＬＤ的诊断。     

多发性硬化三例标本MRI长T2信号与病理对照研究

采用磁共振成像（ＭＲＩ）与病理对照方法探讨多发性硬化（ＭＳ）ＭＲＩ异常长Ｔ２信号与病理改变的关系。对３例经１０％福尔马林固定的全脑标本（其中１例含脊髓）行自旋回波（ＳＥ）序列扫描，对照ＭＲＩ图像所示的长Ｔ２信号行标本大体及镜下观察。３例ＭＳ均显示有长Ｔ２信号，其病理基础除ＭＳ斑块外还可见坏死软化灶及空洞形成。斑块状长Ｔ２信号具有特征性的ＭＲＩ表现：直角脱髓鞘征，见于病程长者（例１）。坏死软化灶及空洞形成引起的非斑块状长Ｔ２信号形态分布不一，以病程短、起病急者为著（例２、３），后者脊髓受累程度亦严重。ＭＲＩ是诊断ＭＳ最有价值的影像学检查方法。ＭＳ长Ｔ２信号的病理基础除典型硬化斑外还有坏死软化灶及空洞形成。当临床拟诊为ＭＳ，而ＭＲＩ仅显示非斑块状长Ｔ２信号时，应警惕为急性发病的ＭＳ。     

多发性硬化的MRI增强的临床意义研究

目的探讨在ＭＲＩ增强中多发性硬化（ＭＳ）病灶强化的机制与临床的关系。方法对２３例ＭＳ患者均作ＭＲＩ平扫与增强扫描,其中９例作ＭＲＩ平扫与增强复查,使用德国西门子公司Ｐ８０．２Ｔ永磁型ＭＲ成像仪,采用ＳＥ序列。造影剂使用ＧＤ－ＤＴＰＡ,剂量为０．１ｍｌ／ｋｇ。结果ＭＲＩ平扫,ＭＳ病灶呈长Ｔ１长Ｔ２的斑片状异常信号,静脉注入ＧＤ－ＤＴＰＡ后产生的强化。用以分析ＭＳ的ＭＲＩ强化特征与临床分型的关系。结论不同临床类型的ＭＳ患者,在ＭＲＩ平扫及增强上均有不同的表现,这可能与ＭＳ斑的形成有不同的病理机制有关     

磁共振扩散成像诊断急性脑梗死

目的：评价扩散成像（ＤＷＩ）磁共振对急性脑梗死的诊断价值。方法：用ＤＷＩ诊断急性脑梗死１０例，并与传统ＣＴ扫描及常规ＭＲＩ结果比较。结果：ＤＷＩ在发病６小时之内已能明确发现脑内相应对高信号灶，常规ＭＲＩ需在发病１２小时后才能显示病灶，其中Ｔ２ＷＩ较Ｔ１ＷＩ敏感，而ＣＴ则需２４小时左右才能显示脑内病灶的存在。ＤＷＩ显示的病灶较Ｔ２ＷＩ稍大，所有新病灶在ＤＷＩ上均为高信号。结论：ＤＷＩ对诊断超早期脑梗     

急性脑梗塞病人白细胞变形能力变化及临床意义

本文观察了急性脑梗塞（ＡＣＩ）病人白细胞变形能力（ＬＤ）的变化，同时检测了血浆总胆固醇（ＴＣ）、甘油三酯（ＴＧ）、纤维蛋白原（Ｆｉｇ）、脂质过氧化物代谢产物丙二醛（ＭＤＡ）和血浆镁离子的浓度变化。结果显示，ＡＣＩ病人ＬＤ较对照组明显降低，差异有显著性意义（Ｐ＜０．００１），且ＬＤ随着血浆ＴＣ、ＴＧ、Ｆｉｇ、ＭＤＡ浓度增高和血镁浓度降低而进一步降低。本结果提示，在预防和治疗ＡＣＩ过程中，提高ＬＤ，改善微循环，对增加缺血脑组织的血液灌流，缩小梗塞面积和改善预后具有重要的临床意义。     

实验性急性脑梗塞早期MRI表达与病理对照研究

目的 阻断狗大脑中动脉建立急性脑梗塞动物模型，观察早期ＭＲＩ表现及其病理性改变。方法 将１６只成年随机分为实验组（１０只）和对照组（６只）。经颞开颅阻断一侧大脑中动脉（ＭＣＡ），造成ＭＣＡ供应区急性缺血性脑梗塞，术后４、６、８、１２ｈ行ＭＲＩ薄层扫描；取出动物大脑观察病理改变，测定不同时相梗塞区Ｔ２时间和组织水含量。结果 梗塞２ｈＭＲＩＴ２加权可见尾状核头部、豆状核信号增高；６ｈＭＲＩ可见了尾状核     

MRI和BAEP在多系统萎缩不同类型中的诊断价值

目的：探讨多系统萎缩（ＭＳＡ）的临床特点,以及磁共振成像（ＭＲＩ）和脑干听觉诱发电位（ＢＡＥＰ）对不同类型ＭＳＡ的诊断价值。方法：对５０例ＭＳＡ的临床资料、ＭＲＩ和ＢＡＥＰ进行回顾性分析。结累：５０例ＭＳＡ中,散发型橄榄桥脑小脑萎缩（ＳＯＰＣＡ）２５例,占５０．０％,临床上以小脑型共济失调为主要表现,ＢＡＥＰ最敏感,ＭＲＩ次之;纹状体黑质变性（ＳＮＤ）１５例,占３０％,以肌张力增高为主,ＭＲＩ最敏感,ＢＡＥＰ次之。Ｓｈｙ—ｄｒａｇｅｒ综合征（ＳＤＳ）１０例,占２０％,以直立性低血压和头晕为主,ＢＡＥＰ最敏感。而且将ＳＮＤ与原发性帕金森综合征（ＩＰＤ）的ＢＡＥＰ相比,前者的敏感性明显升高,差别有显著性。结抡：ＭＳＡ分型不同临床表现各有侧重,ＭＲＩ及 ＢＡＥＰ在 ＭＳＡ诊断和鉴别诊断中有极重要价值。     

多系统萎缩的临床与CT及磁共振分析

目的　评价临床表现与ＣＴ、磁共振（ＭＲＩ） 结合对多系统萎缩（ＭＳＡ） 的诊断价值。方法　选择５６ 例多系统萎缩病人，其中橄榄桥脑小脑萎缩（ＯＰＣＡ）３７ 例，Ｓｈｙ－ Ｄｒａｇｅｒ 综合征（ＳＤＳ）１３ 例，纹状体黑质变性（ＳＮＤ）６ 例。全部病人均行头颅ＣＴ、ＭＲＩ检查，并对其临床表现、分型、ＭＲＩ进行比较。结果　临床发现各型早期各有特点，且ＭＲＩ表现也各不相同。结论　临床表现与ＭＲＩ结合可提高ＭＳＡ 中ＯＰＣＡ、ＳＮＤ的诊断率，但在ＳＤＳ病人ＭＤＩ改变不明显。头颅ＣＴ对ＭＳＡ 诊断意义不大。     

MRI of anterior spinal artery syndrome.

In this serial MRI study a 24 year old man presenting anterior spinal artery syndrome was examined. In the acute stage, spin echo sequences showed an enlarged cervical cord on a T1 weighted image and high signal intensity in the enlarged portion of the cord on a T2 weighted image. The findings were interpreted as oedema in the grey and white matter subsequent to ischaemia. In the chronic stage, inversion recovery techniques revealed a distinct focus in the anterior two thirds of the cord at the low cervical level.     

MRI in 31 patients with Beh?et's disease and neurological involvement: prospective study with clinical correlation.

Thirty one patients with Behçet's disease and neurological manifestations were prospectively studied with MRI. Cerebral venous thrombosis was diagnosed in 10 patients. MRI performed during the acute illness in eight patients showed an abnormally high signal on the T2 weighted sequences in the occluded sinus. MRI showed minor flow abnormalities suggestive of partial recanalisation of the sinus in two cases at a later clinical stage. MRI can be an alternative, non-invasive, investigation to intravenous cerebral angiography. In 13 patients with central nervous system involvement, MRI performed during the acute illness showed multiple hyperintense lesions on T2 weighted sequences. They were usually less than 5 mm, scattered and confluent, mainly in the white matter, distributed in the hemispheric white matter in nine cases, brainstem in eight, basal ganglia and thalamus in five, and cortex in two. MRI abnormalities were usually associated with appropriate clinical deficits, but were larger and more disseminated than expected.     

Reversible posterior leukoencephalopathy syndrome in two patients with microscopic polyarteritis nodosa]

We report here two cases (72-year-old woman, 77-year-old-woman) with perinuclear anti-neutrophil antibody (P-ANCA) positive microscopic polyarteritis nodosa (mPN). Both patients presented with generalized convulsion, consciousness disturbance and severe hypertension several days after the administration of high dose methylpredonisolone followed by oral predonisolone. CT brain scan showed hypodensity area on bilateral posterior lobes. MRI T2 weighted image and FLAIR image showed increased signal intensity on the occipital gray and white matter. Although diffusion weighted MRI disclosed slightly high signal intensity, apparent diffusion coefficient (ADC) value at the occipital gray and white matter remained normal or even elevated. These findings, which were consistent with vasogenic edema, lead us to diagnose them as suffering from reversible posterior leukoencephalopathy syndrome (RPLS). After the second administration of high dose methylpredonisolone, their symptoms and signs, together with the MRI findings, gradually improved. To our knowledge, this is the first report concerning RPLS in a patient with mPN.     

Adrenoleukodystrophy. Value of contrast-enhanced MR imaging

In its early stage adrenoleukodystrophy (ALD) is characterized by hypodensity at CT and signal abnormalities at RMI (low-intensity signal on T1-weighted sequences, high-intensity signal on T2-weighted sequences) in the white matter of the parieto-occipital region and the splenium of the corpus callosum. These CT and RMI abnormalities are suggestive of ALD in children with progressive alteration of the superior brain functions, but they are not specific of the disease. The authors present two cases of ALD and underline the almost pathognomonic value of contrast-enhanced ribbons found at the periphery of low-intensity signal plaques after gadolinium injection. These areas of blood-barrier disruption on a background of inflammation and active demyelination appear, on T2-weighted sequences, as ribbons of low-intensity signal within plaques of high-intensity signal. MRI is also superior to CT in detecting abnormalities located in the posterior fossa, notably lesions of the auditory fibres.     

磁共振扩散加权成像在鉴别新陈腔隙性脑白质梗死中的价值

目的分析新陈腔隙性脑白质梗死的T2WI、扩散加权成像(DWI)信号特点，比较两种梗死的病灶与脑白质、病灶与脑脊液对比度及表观扩散系数(ADC)，评价DWI在鉴别新陈腔隙性脑白质梗死方面的作用。方法急性期腔隙性脑白质梗死患者27例，选择43例陈旧腔隙性脑白质梗死患者作对照。测量病灶、正常脑白质、脑脊液信号强度，计算病灶与脑白质、病灶与脑脊液的对比度。测量病灶、正常脑组织、脑脊液的ADC值并比较。结果(1)急性脑白质腔隙性梗死DWI呈高信号，ADC图呈等或低信号。DWI的病灶与脑白质、病灶与脑脊液对比度均优于T2WI。(2)陈旧脑白质腔隙性梗死DWI呈等信号，ADC图呈高信号。DWI的病灶与脑白质对比度不如T2WI。(3)DWI图像上，急性腔隙性脑白质梗死病灶与脑白质、病灶与脑脊液对比度明显高于陈旧病灶，ADC则明显低于陈旧病灶，有助于区分新陈腔隙性梗死。结论DWI的检查时间短，诊断和鉴别意义大，建议在可能的情况下，将DWI作为急性卒中样发作患者的常规检查序列。     

孪生兄弟患肾上腺脑白质营养不良的临床、影像学和病理特征

目的探讨孪生兄弟患肾上腺脑白质营养不良(ALD)的临床、影像学及病理特征。方法回顾性分析2例同患ALD孪生兄弟的临床资料及1例(兄)脑病理检查资料。结果1例(兄)临床表现为脑型ALD,其头部MRI示枕顶叶白质及胼胝体后部广泛性T1WI低信号,而T2WI为高信号;病理改变为顶枕叶白质弥散性脱髓鞘病变,但皮质下U形纤维完整。而另1例(弟)则表现为以脊髓损害为主,头部MRI未见异常;脊髓MRI示脊髓变细,周边见线条状等信号;为青少年肾上腺脊髓神经病变型。结论即使孪生兄弟同患ALD,其临床表现与影像学所见及病理改变也可完全不同。     

海洛因海绵状白质脑病的影像学特征

目的　探讨海洛因海绵状白质脑病 (HSL E)的 CT、MRI和 PET特点。方法　对 2 9例患者的CT、MRI以及 4例患者的 PET资料进行分析。结果　 (1) CT和 MRI显示病变位于双侧小脑、内囊后肢、枕顶叶深部等部位白质 ,病灶广泛且对称 ;(2 ) CT示界限清楚的低密度病灶 ,MRI呈长 T1 WI、长 T2 WI异常信号 ,无水肿 ,快速反转恢复序列 (FL AIR)和增强扫描提示血脑屏障无破坏 ,PET显示为低代谢或无代谢病灶 ;(3)未治疗患者内囊后肢、枕叶和小脑白质无代谢 ,康复期患者代谢明显减低 ;(4 )临床症状改善者和未治疗者小脑皮质代谢降低 ,临床症状明显改善者代谢正常。结论　 HSL E患者的 CT和 MRI改变多局限于白质 ,极为相似。 PET显示病变部位低代谢或无代谢 ,小脑皮质和白质代谢的恢复对 HSL E患者的临床转归非常重要 ,故判断 HSL E患者的转归 ,PET较之 MRI更有价值     

神经白塞病的影像学特点和动态变化

目的总结神经白塞病在不同序列MRI检查上病灶的好发部位和特点。方法回顾性分析7例神经白塞病患者的MRI检查资料。MRI检查序列包括:T1WI、T2WI、核磁共振弥散加权成像、表观弥散系数和核磁共振波谱。结果 7例神经白塞病患者均表现为脑实质损害。最常见的神经系统症状包括癫痫发作、头痛、躯体感觉和运动障碍、延髓麻痹、精神障碍、认知障碍和锥体束征。MRI检查常见受累部位包括脑干、内囊、皮质下白质和基底节。病灶在MRI上表现为T1WI为等信号或低信号,T2WI为高信号,其中3例可见异常强化。2例神经白塞病患者表现为核磁共振弥散加权成像稍高信号,表观弥散系数信号轻度升高,核磁共振波谱未见明显异常代谢区。3例患者在首次MRI检查后15d～5个月进行随访发现原发病灶均减少或消失,但可出现新发病灶。结论神经白塞病是白塞病最严重的并发症之一,MRI检查是诊断神经白塞病非常敏感的方法,神经白塞病以脑实质损害为主,不同序列的MRI检查具有特征性改变。     

Reduced signal intensity of T2 weighted MR imaging of thalamus and putamen in multiple sclerosis in Japan]

Although studies using magnetic resonance imaging (MRI) in multiple sclerosis (MS) patients have focused on findings in the white matter because of its demyelination pathogenesis, Drayer et al. have reported a high incidence of low signal intensity on T2 weighted MR imaging (MRI) in gray matter such as the thalamus and putamen. In Japan there has been no investigation of MRI findings of the basal ganglia in MS patients. Therefore, we attempted to examine the incidence and clinical significance of the imaging phenomenon in 34 Japanese patients with MS (12 male, 22 female, ages 18-54 years). As it is well known that the spinal cord and optic nerves are more frequently involved in MS than the brain in Japanese patients, we divided the patients into two subgroups based on their clinical features and the major sites of demyelination on MRI. One group included the 17 patients whose demyelinations occurred in the brain (brain-type), and the other group included the 17 patients whose abnormalities were found in the spinal cord with or without optic nerve involvement (non-brain type). As a control, MRI studies were also performed in age-matched patients with headache without any neurological signs. On T2 weighted MRI, decreased signal intensity in the thalamus was found in only four patients with MS, 11.8% of the total number examined, and in the putamen in three patients with MS, 8.8% of the total examined. All of the patients who showed abnormal decreased signal intensity in the thalamus and/or putamen belonged to the brain-type group, and these incidences were 23.5% in the thalamus and 17.6% in the putamen among the brain-type patients. No patient belonging to the non-brain type showed this imaging sign. This imaging sign was well correlated with the degree of white matter abnormalities in the brain estimated as a score according to modified Callanan et al.'s method. In addition, this sign was also correlated with the expanded disability status scales (EDSS) in the brain-type patients. These observations suggest that the axonal damages due to severe demyelination may induce the impaired transport of iron resulting in an accumulation of ferritin in the thalamus and putamen, and would cause decreased signal intensity on T2 weighted MRI. The relatively low incidence of decreased signal intensity in the thalamus and putamen in this study may be associated with differences in the clinical phenotype of MS between Japan and the USA. In brain-type patients the evaluation of basal ganglia on T2 weighted MRI may be a useful tool for estimating patients' disabilities.