多发性硬化MRI研究新进展

多发性硬化（multiple sclerosis，MS）是中枢神经系统最常见的脱髓鞘疾病，其诊断一直强调病史和体格检查的重要性。但是随着MRI技术的发展与应用．这一情况发生了改变。2000年7月制订的McDonald诊断标准第一次将MRj用于MS的诊断，并明确地说明了MS时间和空间上多发性的MRI证据．从而有利于对患者尤其是表现为临床孤立综合征（clinically isolated syndrome，CIS）的患者进行早期诊断。超微型超顺磁性氧化铁颗粒（ultrasmall superparamagnetic iron oxides，USPIOs）对比剂及MRI新技术在显示MS特异性征象、病变与病理变化及临床功能障碍之间的相关性、定量研究、早期诊断及疗效监测等方面提供了更多特异性信息。本文对此进行综述。     

多发性硬化脑内病灶MRI典型及不典型表现:附82例MRI分析

目的分析我国多发性硬化病例典型及不典型影像学改变。方法回顾经McDonald诊断标准明确诊断的82例多发性硬化患者的头部MRI检查结果,分析病灶部位、大小、数目、形状、信号强度及强化方式等。结果我国多发性硬化的典型影像学表现:（1）病灶部位以脑室旁（62例,75.61%）及幕上深部白质（55例,67.07%）多见。（2）病灶数目多在10个以上（62例,75.61%）。（3）病灶直径以≤1 cm为主（62例,75.61%）,>5 cm次之（23例,28.05%）。（4）信号强度及强化特征为T₁WI平扫呈等或略低信号,T₁WI高信号,PDwI高于脑脊液中水信号;T₁WI增强图像黑洞从微小至大片状均可见,形状多呈类圆形或条片状;<1 cm病灶显示结节状强化,1～5 cm病灶一般呈环状强化,>5 cm病灶以边缘强化或内部呈不规则环状强化为主,皮质病灶多见弓状强化。我国多发性硬化的不典型影像学表现为:病灶较大,最大直径>5 cm（23例,28.05%）;强化显著且强化持续时间较长;脑干病灶多见（61例,74.39%）。结论侧脑室旁或深部白质内多发小病灶是多发性硬化的典型MRI表现;侧脑室旁病灶致侧脑室变形、大脑凸面的微小黑洞及侧脑室边缘的条片状黑洞,以及近皮质或围绕侧脑室颞角的弓状强化具有重要诊断价值。病灶大、强化显著及脑干病灶多见,是我国多发性硬化不同于欧美地区的主要表现。     

MRI在多发性硬化中的应用

近年来波谱成像、磁化传递成像、弥散张量成像、双反转回波成像等磁共振新技术在多发性硬化的早期诊断、病情评估、治疗监测、预后判断及研究中发挥着越来越大的作用。现就磁共振在多发性硬化中的应用做一综述。     

颅脑多发性硬化的临床及MRI诊断

目的 探讨多发性硬化(MS)的临床及MRJ特征,提高对多发性硬化的认识及诊断水平.方法 对20例颅脑MS患者临床资料、病灶部位、形态、MR信号及强化特点、胼胝体改变进行回顾性分析评价.结果 MS以青、中年女性稍多见,急性、亚急性起病,多以视觉障碍或肢体感觉、运动障碍为首发症状.视觉诱发电位大多数异常.MRJ检查18例发现病灶,敏感性90%(18/20).病灶以双侧侧脑室旁、额叶皮层及皮层下、半卵圆中心多发.病灶大、小不等,多数为圆形、卵圆形."直角脱髓鞘征"及"白质变脏征"是两个较为典型的征象.T1WI上表现为等、低信号,T2WI及Flair序列上表现为高信号,Flair序列显示病灶更清晰.增强扫描病灶可呈结节状强化、环状强化、弧形强化或无强化.结论 MS的临床及MRI表现具有一定特征.MRI有助于脑部MS的诊断及鉴别诊断,是诊断MS最敏感的成像方法.     

多发性硬化脑内病灶MRI典型及不典型表现：附82例MR1分析

目的分析我国多发性硬化病例典型及不典型影像学改变。方法回顾经McDonald诊断标准明确诊断的82例多发性硬化患者的头部MRI检查结果,分析病灶部位、大小、数目、形状、信号强度及强化方式等。结果我国多发性硬化的典型影像学表现：（1）病灶部位以脑室旁（62例,75．61％）及幕上深部白质（55例,67．07％）多见。（2）病灶数目多在10个以上（62例,75．61％）。（3）病灶直径以≤1cm为主（62例,75．61％）,〉5cm次之（23例,28．05％）。（4）信号强度及强化特征为T1WI平扫呈等或略低信号,T2WI高信号,PDWI高于脑脊液中水信号;T1WI增强图像黑洞从微小至大片状均可见,形状多呈类圆形或条片状;〈1cm／病灶显示结节状强化,1～5cm病灶一般呈环状强化,〉5cm病灶以边缘强化或内部呈不规则环状强化为主,皮质病灶多见弓状强化。我国多发性硬化的不典型影像学表现为：病灶较大,最大直径〉5cm（23例,28．05％）;强化显著且强化持续时间较长;脑干病灶多见（61例,74．39％）。结论侧脑室旁或深部白质内多发小病灶是多发性硬化的典型MRI表现;侧脑室旁病灶致侧脑室变形、大脑凸面的微小黑洞及侧脑室边缘的条片状黑洞,以及近皮质或围绕侧脑室颞角的弓状强化具有重要诊断价值。病灶大、强化显著及脑干病灶多见,是我国多发性硬化不同于欧美地区的主要表现。     

多发性硬化患者的MRI及多种诱发电位研究

目的探讨磁共振成像(MRI)和诱发电位(EPs)在诊断多发性硬化中的价值。方法对68例多发性硬化患者的头颅MRI、脑干听觉诱发电位、视觉诱发电位以及体感诱发电位等指标进行回顾性分析和比较。结果多发性硬化患者的头颅MRI、脑干听觉诱发电位、视觉诱发电位以及体感诱发电位的异常率分别为91.2%(62/68)、80.9%(55/68)、82.4%(56/68)和77.9%(53/68),且均发现多发性硬化的亚临床病灶;两项或多项联合检查的异常率较单项检查的异常率增高,差异有统计学意义(P<0.01)。结论头颅MRI和诱发电位检查有助于临床早期确诊多发性硬化,联合应用可使其敏感性提高。     

精神分裂症的脑萎缩及其相关因素的分析

探讨精神分裂症患者脑萎缩的发生率及其相关因素。方法对１４２例精神分裂症患者和４６例正常人进行了脑部磁共振检查,对其临床相关因素进行了分批发裂症患者的脑萎缩发生率为３１．７％;两组脑萎缩发生率和脑空评分、第三脑室最大宽度、前角指数、脑室脑比率的值均有显著性差异;     

诱发电位和MRI检查在多发性硬化诊断中的价值

目的探讨诱发电位(EPs)和MRI检查在多发性硬化(MS)诊断中的价值。方法收集69例MS患者的临床资料、视觉诱发电位、体感诱发电位、脑干听觉诱发电位、磁刺激运动诱发电位以及MRI结果,比较不同检测方法对其临床诊断的价值。结果 MS患者的视觉诱发电位、体感诱发电位、听觉诱发电位、运动诱发电位以及MRI的异常检出率分别为69.57%(48/69)、50.72%(35/69)、55.07%(38/69)、42.03%(29/69)、78.26%(54/69)。4项诱发电位检查总异常检出率为86.96%(60/69),与MRI检查结果比较差异无统计学意义(P=0.178)。EPs和MRI检查均能发现临床下病灶:14例患者经MRI检查发现病灶但无相应临床症状;15例患者有临床症状而MRI检查未见相应病灶,但EPs检查可见异常。结论 MRI和EPs检查具有相互补充作用,结合临床合理选择使用此两种检查有助于提高MS诊断的敏感性。     

精神分裂症脑萎缩及其相关因素研究

目的 探讨精神分裂症患者脑萎缩的发生率及其相关因素。方法 对142例精神分裂症患者(病例组)和46例正常对照组进行了脑部磁共振(MRI)检查,应用MRI定量测量分析脑室、脑沟、并对病例组的脑萎缩与临床相关因素进行了相关分析。结果 精神分裂症患者的脑萎缩发生率为31.7％;两组的脑萎缩发生率和脑萎缩评分(GA分)、第三脑室最大宽度(TVW)、前角指数(FHI)、脑室脑比率(VBR)的值均有显著性差异;病例组GA评分、TVW、FHI、VBR的值均与病前适应能力、病程、阴性症状量表总分、副反应量表总分等有显著相关性,而与性别、年龄、家族史、起病形式、阳性症状量表总分、简明精神病评定量表总分、脑电图(EEG)异常、药物治疗总时间、药物最大日剂量、住院次数、电休克(ECT)治疗次数、临床疗效总评量表的疗效总评项目分等无显著相关性。结果 提示精神分裂症可能与非特异性脑室、脑沟结构异常有关,特别是与脑萎缩程度有关,但其因果关系有待进一步研究。     

精神分裂症脑萎缩的MRI研究

目的 了解精神分裂症患者的脑萎缩是疾病初期即已发生，还是随病程逐渐进展。方法 研究对象选取符合DSM-Ⅲ精神分裂症诊断标准的住院患者95例，正常对照组20例，按规定序列作头颅核磁共振扫描，测定第三脑室宽度、两侧第三脑室距脑岛面距离及两侧尾状核头部宽度。并以病程5年为限，分为短病程组和长病程组。结果 ①病例组第三脑室显著增宽，尾状核头部缩小。②短病程组与长病程组各组值无显著性差异。③病程与第三脑室宽度、两侧第三脑室距脑岛面距离及两侧尾状核头部宽度均无显著相关性。结论 精神分裂症患者脑萎缩明显，且与病程、服药无关，在疾病早期即已发生。     

Depressive symptoms and MRI changes in multiple sclerosis

To determine whether changes in specific regions of the brain can contribute to the development of depression in patients with multiple sclerosis (MS). We prospectively studied 90 patients with clinically definite MS. Disability, independence, cognitive performances, and depressive and anxiety symptoms have been assessed at baseline and 2 years later. At these two time-points, patients underwent a 1.5-T magnetic resonance examination of the brain including T1- and T2-weighted images. Calculation of regional and total lesion loads (LL) have been performed by a semiautomatic technique; total and regional brain volumes have been calculated by a fully automatic highly reproducible computerized interactive program. Measurements of LL did not show any significant difference between depressed and non-depressed patients. Brain atrophy was significantly more conspicuous in the left frontal lobe (P=0.039), in both frontal lobes (P=0.046) and showed a trend towards a difference in the right frontal lobe (P=0.056), in the right temporal lobe (P=0.057) and in both temporal lobes (P=0.072) of depressed patients. Disability, independence and cognitive performances were similar in depressed and non-depressed patients (P=NS). Spearman correlation analysis and multiple-regression analysis demonstrated that the severity of the depressive symptoms score was associated both with the disability score and the right temporal brain volume. Destructive lesions in the right temporal lobe can contribute to the severity of depression in patients with MS but the influence of the severity of neurological impairment should be taken into account.     

The relationship of brain and cervical cord volume to disability in clinical subtypes of multiple sclerosis: a three-dimensional MRI study

OBJECTIVES: Brain and cervical cord volume is a potentially valuable index marker of irreversible pathological processes in multiple sclerosis (MS). Volume in both brain and cervical cord regions in the same patients has only been investigated in a small number of subjects. We aimed at measuring volume in different parts of the central nervous system, and its relationship with clinical measures, in relapsing-remitting (RR) and secondary progressive (SP) MS patients. MATERIAL AND METHODS: Conventional dual echo and three-dimensional (3-D) magnetization prepared rapid acquisition gradient echo imaging was performed on 97 (49 RR and 48 SP) MS patients, and on 31 age- and gender-matched healthy controls. The volumes of the supratentorial brain, lateral ventricles, brainstem, cerebellum and upper cervical cord (UCC) were determined on 3-D magnetic resonance imaging. RESULTS: RR MS patients had significantly smaller supratentorial brain (P=0.002) and larger lateral ventricles (P=0.047) compared with controls, but no differences were found for cerebellum, brainstem and UCC volumes. Significantly smaller supratentorial brain (P<0.0001), cerebellum (P=0.007), brainstem (P=0.0004) and UCC (P<0.0001) volumes, and larger lateral ventricles (P<0.0001) were observed in SP MS patients than in controls. In RR MS, T2-lesion volume correlated with supratentorial (r=-0.46, P=0.0009), lateral ventricular (r=0.65, P<0.0001), cerebellar (r=-0.42, P=0.003) and brainstem (r=-0.35, P=0.01) volumes, but not with UCC volume (r=-0.18, P=0.22). In SP MS, apart from lateral ventricular volume (r=0.52, P=0.0002), none of the estimated structural volumes correlated with T2-lesion volume. The UCC volume correlated with brainstem volume in both RR MS (r=0.35, P=0.016) and SP MS (r=0.38, P=0.007). Multiple regression analysis showed that supratentorial brain volume in RR group, and UCC volume in SP group, were single significant contributors (P=0.01 and 0.04, respectively) to the Expanded Disability Status Scale of all factors entered into the regression model. CONCLUSION: Atrophy is confined to the supratentorial compartment early in the disease course corresponding to the RR stage, but becomes more pronounced in the brain and cervical spinal cord in the SP phase. The estimate of cervical cord volume for SP MS is relevant to functional disability and may be helpful in monitoring MS evolution in the progressive form of disease.     

Brain MRI in late-onset multiple sclerosis

Multiple sclerosis (MS) with clinical onset after 50 years of age is unusual (between 1 and 6%) and is frequently misdiagnosed. Furthermore, brain magnetic resonance imaging (MRI) abnormalities are frequently observed in subjects over 50 years of age. The aim of this study was to describe brain MRI in late-onset MS to evaluate the sensitivity and specificity of radiological MS criteria in patients aged over 50 years. We evaluated the brain MRI of 20 patients with onset of MS after 50 years of age. We compared these MRI with 26 controls matched for age, sex and vascular risk factors. MRI were blindly analysed by two neuroradiologists according to Paty et al.'s [Neurology38 (1988) 180] criteria, Fazekas et al.'s [Neurology38 (1988) 1822] criteria and Barkhof et al.'s [Brain120 (1997) 2059] criteria. The mean age at MRI scanning was 58 years. Sensitivity was 90% for Paty et al.'s criteria, 80% for Fazekas et al.'s criteria and 85% for Barkhof et al.'s criteria. Specificity was 54% for Paty et al.'s criteria, 69% for Fazekas et al.'s criteria and 65% for Barkhof et al.'s criteria. Barkhof et al.'s criteria are less specific in older patients than in young patients. We suggest that spinal cord MRI and cerebrospinal fluid analysis should be systematically performed in suspected late-onset MS in order to increase the specificity of the diagnosis.     

Correlation between brain MRI lesion volume and disability in patients with multiple sclerosis

In this study we evaluated the relationships between clinical variables and lesion volumes measured from magnetic resonance imaging (MRI) scans in a large cohort of multiple sclerosis (MS) patients. One hundred and thirty patients with MS entered the study: 36 patients had relapsing-remitting (RR), 39 benign (B), 42 secondary progressive (SP) and 13 primary progressive (PP) courses. There was a significant correlation (r=0.3; p=0.0006) between the total lesion load and the EDSS score when the whole cohort of patients was considered. This correlation increased (r=0.5) when only patients with RRMS and SPMS were considered. Our data indicate that a correlation between disability and MRI lesion volume in MS exists, but its strength is moderate.     

Volumetric quantitation by MRI in primary progressive multiple sclerosis: volumes of plaques and atrophy correlated with neurological disability

In primary progressive multiple sclerosis (PPMS) abnormalities in brain magnetic resonance imaging (MRI) differ from abnormalities in other subtypes of multiple sclerosis (MS). It was investigated whether the extent of brain and spinal cord MRI abnormalities is reflected in the neurological disability in PPMS. Focal and diffuse changes and atrophy in central nervous system (CNS) in patients with PPMS (n = 28) and healthy controls (n = 20) were assessed by semi-automatic MRI segmentation and volumetric analysis. The measurements were related to neurological disability as expressed by the expanded disability status scale (EDSS), the regional functional scoring system (RFSS), the arm index and the ambulation index. Plaques in T1- and/or T2-weighted images were seen in all brains, while spinal plaques were detected in 23 of 28 patients (82%). The total volumes of brain and spinal cord were significantly smaller in patients than in controls (P = 0.001 and 0.000, respectively). The volumes of T1 or T2 lesions in the brain correlated to the ambulation index (r = 0.51, P = 0.005 and r = 0.53, P = 0.004, respectively). No correlations were detected between MRI measurements and total EDSS score, but relative brain atrophy correlated inversely with the total RFSS scores, poor arm index and higher cerebral disturbances (r = -0.53, P = 0.004; r = -0.53, P = 0.004; and r = -0.52, P = 0.005, respectively). Although the number of spinal T2 lesions correlated with sensory disturbances (r = 0.60, P = 0.001), no correlations were found between EDSS subscores and spinal cord atrophy. These findings show that marked atrophy of brain and spinal cord detected by volumetric quantitation correlates with neurological disability. This observation indicates the importance of neurodegenerative events in PPMS.     

Sensitivity of delayed gadolinium-enhanced MRI in multiple sclerosis

Introduction - We performed this study to define the sensitivity of delayed gadolinium-enhanced magnetic resonance imaging (MRI) in detecting active lesions in the brains of patients with multiple sclerosis (MS). Material and methods - T₁weighted images were obtained in 27 patients with relapsing-remitting or secondary progressive MS before, 5–7 min and 20–30 min after the injection of 0.1 mmol/kg gadolinium-DTPA. Results - One-hundred-and-three enhancing lesions were found on the early and 110 on the delayed scans (increase = 6.4%). Six patients had 8 additional lesions in the delayed scans, while 1 patient had 1 more lesion on the early scan. Two of the 12 (17%) patients with no enhancing lesions on the early scans had 2 enhancing lesions on the delayed scans. The average increase of enhancing lesion detection with delayed scanning was 14.5% for those patients who already had enhancing lesions on the early post-contrast scans. A significant increase of the enhancing lesion volume was found with delayed scanning (P=:0.004). Conclusion - These data indicate that it is possible to increase MRI sensitivity in detecting MS active lesions by delaying the scanning after gadolinium injection.     

Transitional progressive multiple sclerosis: MRI and MTI findings

Transitional progressive multiple sclerosis (MS) is quite an unusual form of presentation and course of the disease. A case with this progressive form is presented and brain MRI and MTI findings are discussed in relation to the possible insight they may provide for understanding the mechanisms that determine progressive disability in MS.     

Blood cholesterol and MRI activity in first clinical episode suggestive of multiple sclerosis

OBJECTIVES: The present study was planned to investigate the relationship between the plasma lipid profile and disease activity in patients with a first clinical episode suggestive of multiple sclerosis (MS). MATERIAL AND METHODS: Eighteen consecutive out-patients underwent a monthly brain magnetic resonance imaging (MRI), blood sample and neurological assessment over 6 months. Blood samples were used to evaluate total cholesterol and triglyceride levels as well as their lipoprotein fractions. Plasma total apolipoprotein E concentration was also determined. RESULTS: We found a significant correlation between the mean number of enhancing lesions and the mean plasma level of both total and low density lipoprotein cholesterol. The total plasma cholesterol level increased on average by 4.4 mg/dl for each enhancing lesion. CONCLUSION: Our preliminary data suggest a potential role of plasma cholesterol level as a biological marker of disease activity after a first demyelinating event. Further studies need, however, to be designed to determine whether the plasma cholesterol level is of practical use in monitoring the disease course.