MRI测量脑室、脑裂在Alzheimer病的应用研究

目的：定量评价Alzheimer病（alzheimer disease,AD)组，血管性痴呆（vascular dementia,VD)组、与年龄、性别相匹配的健康对照（health control,HC)组脑萎缩情况，有助于完善AD MRI的研究。资料与方法。使用Toshiba 1.5T超导MR扫描仪，对20例临床诊断为AD的患者、20例VD患者、20名HC者进行检查。对脑室、脑裂进行定量测量，并进行统计学处理。结果：AD、VD组侧脑室体部宽宽指数、侧脑室颞角宽度指数小于HC组，第三脑室宽度大于HC组，两侧外侧裂宽度指数、前绷裂宽度指数、两侧脉络膜裂宽度指数小于HC组。而AD与VD组以上测量指标除侧脑室颞角宽度以外无差别。结论：整体脑萎缩可提示痴呆的存在，但不能作为AD诊断的特异性指标，最好选择测量脑实质萎缩的指标进行AD的研究。     

MRI体积测量内嗅皮层萎缩诊断Alzheimer病的价值

目的　评价MRI测量内嗅皮层体积对诊断Alzheimer病 (AD)的价值。方法　对可能AD和正常对照者各 33名进行MRI检查 ,AD患者平均年龄 (6 6 6± 8 8)岁 ,平均简短精神量表 (MMSE)评分 14 3± 4 1,正常对照组平均年龄 (6 6 5± 7 7)岁 ,MMSE评分为 2 8 0± 2 6。应用磁化准备快速梯度回波成像序列获取三维T1 WI,在重建斜冠状层面上进行两侧内嗅皮层、杏仁核、海马结构、海马旁回、颞叶、侧脑室颞角和侧脑室体部等结构的体积测量 ,所得数值经部分颅内体积标准化处理 ,然后用社会科学统计程序行统计学分析。结果　AD患者上述脑实质结构均明显萎缩 ,脑室扩张 (P <0 0 0 05 )。内嗅皮层的萎缩率最高 (左侧 40 1%、右侧 38 2 % ) ,判别AD与正常人的效果最好 (正确率92 4% )。应用逐步判别方法建立多元判别方程 ,根据轻度AD患者的测量结果 ,左内嗅皮层、左颞叶和右杏仁核等指标联合判别 ,诊断AD的正确率为 97 7% ,由中重度AD患者验证此判别方程可靠 (灵敏度 90 9% )。结论　内嗅皮层MRI体积测量是区分AD与正常人的重要指标。     

联合磁敏感序列及PET/CT对老年轻度认知障碍及阿尔茨海默病患者海马区的临床研究

目的研究正常老年人、老年轻度认知障碍患者(MCI)及阿尔茨海默病患者(AD)海马区引流静脉-侧脑室下静脉变化差异所致的海马神经细胞葡萄糖摄取能力变化,从血管层面对其神经细胞功能进行观察研究。方法采用高场MRI磁敏感序列(SWI)与PET/CT设备分别对15例正常老年人、15例老年MIC患者及15例AD患者进行头颅扫描检查,检测海马引流静脉-侧脑室下静脉的形态改变特征与海马区~(18)F-FDG SUVmax值变化规律。结果与正常老年组对比,老年MCI患者左侧脑室下静脉出现直径变窄、长度变长及分支增多的表现,差异有统计学意义,而左侧海马区SUVmax值未出现有统计学意义的变化,右侧脑室下静脉直径、长度、分支数目及右侧海马区SUVmax值均未出现有统计学意义的变化;与正常老年组对比,AD患者双侧脑室下静脉均出现直径变窄、长度变短及分支减少,差异有统计学意义,双侧海马区SUVmax值均出现有统计学意义的减低。结论海马引流静脉-侧脑室下静脉的形态变化能够导致海马神经细胞对葡萄糖利用的障碍,并且在老年MCI到AD发展的过程中有一定规律。     

阿尔茨海默病侧脑室变化的磁共振研究

目的 探讨阿尔茨海默病(AD)侧脑室变化的特征性磁共振表现,为临床诊断和鉴别诊断提供依据.方法 利用1.5T磁共振对20例AD患者和20名正常对照组行轴位全脑MRI扫描以测量左右侧脑室体积,并每隔一年对同一患者进行连续随访3年,以分析AD患者各侧侧脑室体积变化以及随时间变化的发展趋势.结果 AD组患者左侧、右侧及双侧侧脑室的体积于3年内均明显大于正常对照组(P =0.000);AD患者侧脑室的体积随着时间的推移不断增加且其增加的速率存在着逐渐递增趋势,且左侧侧脑室扩大的程度和速率要比右侧明显.结论 各侧侧脑室体积的动态变化可能是AD患者的特征性影像学表现之一,这也为临床上判别疾病的严重性及预后提供了一定的帮助.     

正常新生儿脑容积的MSCT测量

目的:观测正常新生儿脑容积,为新生儿颅脑疾病的诊断提供正确的CT解剖数据。方法:从行颅脑CT扫描的新生儿中选取42例无异常发现者的CT图像进行测量,利用容积测量软件,用等灰度法均匀涂布所选区域,测量项目为脑容积9项。结果:获得新生儿脑容积9项指标的平均值,全脑容积(419.15±5.33)cm3,左侧大脑半球容积(187.62±2.91)cm3,右侧大脑半球容积(187.61±3.38)cm3,左侧小脑半球容积(17.15±1.05)cm3,右侧小脑半球容积(16.99±0.85)cm3,左侧侧脑室容积(3.76±0.07)cm3,右侧侧脑室容积(3.75±0.08)cm3,第三脑室容积(0.22±0.01)cm3,第四脑室容积(0.24±0.01)cm3,左右大脑半球容积、左右小脑半球容积及左右侧脑室容积差异无显著性(P均>0.05)。结论:MSCT可准确测量正常活体新生儿脑容积,从影像学角度认识正常新生儿脑容积的解剖。     

额颞叶变性亚型与阿尔茨海默病的脑灰质萎缩模式的结构MRI研究

目的 比较分析额颞叶变性(FTLD)的两个亚型,即行为变异型额颞叶痴呆(bvFTD)和原发性进行性失语(PPA),与阿尔茨海默病(AD)的脑灰质萎缩模式,为早期诊断和鉴别诊断提供客观的支持依据.方法 选取FTLD患者23例(bvFTD 10例,PPA 13例)、AD患者30例及认知正常受试者(CN)30名,使用3.0T超导型MR仪及8通道头线圈行图像采集.以高分辨率的三维梯度回波序列(3D-TFE)横断面T1WI作为脑灰质皮层体积的计算序列,采用统计参数图(SPM)8和其工具箱[基于体素的形态测量学方法(VBM)]对3D-TFE T1 WI图像进行空间标准化预处理,最后得到灰质分割图像,进行灰质体积的统计分析,多重比较矫正采用假发现率法,用Xjview工具显示统计分析结果,体素簇大小设为5.采用4 mm的半高全宽高斯核进行空间平滑.统计学分析采用配对t检验.结果 与CN组比较,在bvFTD、PPA和AD组中均出现大脑皮层及皮质下结构(如海马、杏仁核、尾状核等)体积弥漫减少.在bvFTD和PPA组中最明显的萎缩脑区位于额颞叶.与AD组比较,bvFTD组灰质明显萎缩的脑区包括:两侧颞叶上中下回、颞极上回及中回、右侧梭状回和两侧额叶上中下回.颞叶和额叶萎缩具有明显的右侧偏侧性,右侧和左侧颞叶萎缩体素的总体数目为14 301个和5105个(t=-5.03,P＜0.05),右侧和左侧额叶萎缩体素的数目为1344个和125个(t=3.45,P＜0.05),差异均有统计学意义.在PPA组中左侧颞枕叶萎缩明显大于右侧(t=-2.65,P＜0.05),左侧和右侧颞枕叶萎缩体素的数目为15 637个和10 723个.结论 bvFTD、PPA与AD3组具有不同的脑灰质萎缩模式.其中,bvFTD具有右侧额叶和颞叶萎缩的非对称分布特点,与性格改变的特征性表现相关;而PPA具有左侧颞枕叶非对称性萎缩的特点,可解释PPA患者出现语言障碍的特点.     

颅面血管瘤病1例

患者　男 ,18岁。智力低下 ,发作性左侧肢体及颜面部抽搐 10年 ,有时伴意识不清。查体见右侧颜面部及颈部有大片皮肤血管疾 ,未见其它发育异常。头颅ＣＴ扫描 :定位片上见枕顶叶有斑片状钙化。平扫见右侧颞顶枕叶表浅部位脑回样钙化 (图 1) ,右侧蛛网膜下腔增宽 ,右侧颞、顶、枕叶脑皮质明显萎缩 ,中线结构向右侧移位 ,两侧大脑半球不对称 ,且右侧颅壁增厚 (以枕、顶叶为著 )。肘静脉注射 6 0 %的泛影葡胺 10 0ｍｌ(速度为 3ｍｌ/ｓ) ,行增强扫描和ＣＴ脑血管造影 ,显示右侧侧脑室前角及双侧侧脑室后角脉络丛明显强化 ,右侧颞、顶、枕叶软脑…     

脑室内脑膜瘤1例报告

患者　女 ,5 1岁 ,因头痛、头晕 1周而来院就诊 ,全身及神经系统检查均正常。ＣＴ检查 :于ＯＭ线上 +2 0～ +70ｍｍ层面显示右侧侧脑室颞角及侧脑室三角区外形扩大 ,侧脑室三角区内脉络丛受压上移。于侧脑室三角区内可见约 3.0ｃｍ× 2 .5ｃｍ大小的圆形略高密度的肿块影 ,边界清晰 ,密度均匀 ,病变中心区ＣＴ值为 46ＨＵ ,病变周围水肿及占位征象不明显 (图 1)。增强扫描 :右侧侧脑室三角区内肿块呈中等密度的强化(图 2 )。ＣＴ诊断 :右侧侧脑室内脑膜瘤。手术及病理所见 :右颞枕部马蹄形骨瓣开颅 ,打开右侧侧脑室 ,见右侧脑室颞枕部有约 3…     

基于体素的轻度阿尔茨海默病全脑灰质MRI成像分析

目的:利用磁共振T1 WI 3D成像研究轻度阿尔茨海默病患者相对于正常老年人灰质体积改变的特点.方法:对21例轻度AD患者及18例正常老年人进行三维T1WI扫描,利用基于SPM5的DARTEL工具箱对扫描获得的结构图像进行预处理,再对轻度AD组和对照组的令脑灰质体积进行基于体素的统计学比较.结果:轻度AD组的双侧海马、海马旁回及杏仁核、双侧丘脑、双侧颞枕叶皮质、双侧顶下小叶、双侧楔前叶、左侧中央后回、右侧额下回等结构与对照组的灰质密度差异具有统计学意义[P<0.05(FDR)].结论:基于体素的形态学研究能够发现轻度AD患者中大脑灰质广泛的及细微的结构萎缩,从而能够更加早期、全面、客观地反映轻度AD患者的脑结构改变.     

回顾性心电门控多层螺旋CT对急性肺栓塞右心室功能障碍及溶栓前后右心室功能变化的评价

目的 应用ECG门控MSCT前瞻性对中心型急性肺动脉栓塞(APE)患者右心功能障碍及静脉溶栓前后右心功能变化进行评价.方法 96名可疑APE患者进行了ECG门控MSCT胸痛三联检查,25例确诊为中心型肺栓塞.行胸痛三联检查无心肺疾患且性别、年龄匹配的25例作为对照组.APE患者于静脉溶栓后复查MSCT,评价右心功能恢复情况.测量参数包括横断面舒张期的右心室(RV)及左心室(LV)短轴最大内径,RV及LV舒张末期容积(EDV)、收缩末期容积(ESV)、射血分数(EF)、主肺动脉/主动脉直径比.应用单因素方差分析,如果有统计学意义,则采用两两组间q检验.结果 对照组的右心室EDV、ESV、EF值、收缩末期RV/LV容积比、横断面RV/LV内径比及主肺动脉/主动脉直径比分别为(15O.5±24.1)ml、(71.5±18.5)ml、(53.5±4.2)%、1.08±0.04、1.01±0.04及0.99±0.02,中心型APE患者溶栓前以上各值分别为(190.3±16.2)ml、(128.1±13.2)ml、(32.7±3.6)%、2.00±0.26、1.30±0.09及1.34±0.11,溶栓后分别为(159.2±21.5)ml、(80.7±9.4)ml、(49.2±5.9)%、1.22±0.25、1.02±0.02及1.02±0.11.中心型APE患者与对照组比较,右心室ESV(q=6.28,P<0.01)及EDV均增大(q=7.59,P<0.01),EF减小(q=4.82,P<0.01),收缩末期RV/LV容积比增大(q=6.04,P<0.01),横断面RV/LV内径比(q=4.43,P<0.01)及主肺动脉/主动脉直径比增大(q=4.36,P<0.01),左心室EDV减小.中心型APE患者静脉溶栓后,与溶栓前比较,右心室ESV(q=5.03,P<0.01)及EDV减小(q=6.11,P<0.01),EF增加(q=6.29,P<0.01),收缩末期RV/LV容积比减小(q=4.74,P<0.01),横断面RV/LV内径比(q=3.83,P<0.01)及主肺动脉/主动脉直径比减小(q=3.46,P<0.01),左心室EDV增大(q=4.01,P<0.01).结论 回顾性ECG门控MSCT胸痛三联检查可同时检测APE和测量左右心功能,排除其他胸痛疾病,评价溶栓疗效.     

AD和MID患者脑影像学改变与认知水平关系的分析研究

目的：研究AD和MID患者脑影像学改变与认知障碍之间的关系。方法：调查112例门诊和住院AD和MID患者,测定脑C19项指标和MMSEI 1项因子。结果：AD组三、四脑室、基底池、外侧裂、前后角、脑沟及侧脑室的宽度大于MID组,时间地点定向力、语言即刻记忆、注意和计算及图形描画等5项因子分明显低于MID组;AD组三、四脑室、前角和侧脑室宽度分别与地点定向、注意计算、阅读和语言理解因子分呈显著负相关;MID组后角、三脑室、侧脑室及脉络丛球部宽度分别与时间、定向、阅读理解及图形描画因子分呈显著负相关。结论：AD患者脑室系统扩大和认知损害程度比MID患者严重而广泛。MMSE测查结果结合有关病史是MID早期诊断及与AD鉴别诊断的重要依据。     

Ventricular shape biomarkers for Alzheimer's disease in clinical MR images

The aim of this work was to identify ventricular shape-based biomarkers in MR images to discriminate between patients with Alzheimer's disease (AD) and healthy elderly. Clinical MR images were collected for 58 patients and 28 age-matched healthy controls. After normalizing all the images the ventricular cerebrospinal fluid was semiautomatically extracted for each subject and an innovative technique for fully automatic shape modeling was applied to generate comparable meshes of all ventricles. The search for potential biomarkers was carried out with repeated permutation tests: results highlighted well-defined areas of the ventricular surface being discriminating features for AD: the left inferior medial temporal horn, the right medial temporal horn (superior and inferior), and the areas close to the left anterior part of the corpus callosum and the head of the right caudate nucleus. The biomarkers were then used as features to build an intelligent machine for AD detection: a Support Vector Machine was trained on AD and healthy subjects and subsequently tested with leave-1-out experiments and validation tests on previously unseen cases. The results showed a sensitivity of 76% for AD, with an overall accuracy of 84%, proving that suitable biomarkers for AD can be detected in clinical MR images.     

Regional lobar atrophy predicts memory impairment in multiple sclerosis

BACKGROUND AND PURPOSE: In recent studies, measures of whole brain atrophy were strongly correlated with neuropsychological testing, explaining more variance than measures of lesion burden in patients with multiple sclerosis. The relationship between regional lobar atrophy and cognitive impairment is yet to be examined. We endeavored to assess the clinical significance of regional lobar atrophy in multiple sclerosis. METHODS: In a cross-sectional study, we evaluated 31 patients with multiple sclerosis with brain MR imaging and neuropsychological testing. Impairment was determined by comparison with demographically matched healthy controls. MR imaging generated measures of lesion burden (fluid-attenuated inversion recovery hyperintense volume), general atrophy (brain parenchymal fraction), central atrophy (lateral ventricle volume), and lobar atrophy (regional brain parenchymal fraction of frontal, temporal, parietal, and occipital lobes in each hemisphere). Neuropsychological testing emphasized measures of processing speed and memory, because these are commonly affected in multiple sclerosis. RESULTS: Patients with multiple sclerosis showed significant atrophy and impairment on all neuropsychological tests. Regional atrophy accounted for the most variance in all regression models predicting memory performance. Left temporal atrophy was the primary predictor of auditory/verbal memory (partial r's = 0.55-0.61), and both left and right temporal atrophy predicted visual/spatial memory performance (partial r's = 0.51-0.67). Models predicting learning consistency retained frontal lobe atrophy measures (partial r's = 0.44-0.68). Central and general atrophy measures were the primary predictors in modeling processing speed (partial r's = 0.42-0.64). CONCLUSION: Regional atrophy accounts for more variance than lesion burden, whole brain atrophy, or lateral ventricle volume in predicting multiple sclerosis-associated memory dysfunction.     

基于体素的遗忘型轻度认知障碍和轻度阿尔茨海默病全脑白质MR扩散张量成像分析

目的 采用基于体素的分析(VBA)方法研究遗忘型轻度认知障碍(aMCI)患者和轻度阿尔茨海默病(AD)患者全脑白质微观结构改变的特点及其与灰质萎缩模式的关系.方法 选取33例aMCI患者(aMCI组)、32例轻度AD患者(轻度AD组)和31名正常老年人(健康对照组),对全脑进行3.0 T DTI及三维快速扰相梯度反转回波(3DFSPGR)脉冲序列扫描.采用统计参数图(SPM)5软件对被试者的结构图像及各向异性(FA)图进行预处理,然后采用t检验对aMCI组、轻度AD组和正常对照组的全脑灰质体积及FA值进行基于体素的统计学比较,计算出有统计学意义的脑区.结果 与正常对照组比较,aMCI组的双侧额颞叶和左侧枕叶白质、左侧扣带前部、左侧顶下小叶、右侧脑室三角区外上方白质的FA值减低;轻度AD组的双侧额颞枕叶、海马旁白质、扣带前部、胼胝体、侧脑室三角区旁白质、顶下小叶、左侧颞于、左侧丘脑、右侧楔前叶FA值减低.基于体素的形态测量学(VBM),分析发现,aMCI患者组左侧海马、海马旁回、舌回、颞上回,双侧岛叶、颞中回出现了灰质萎缩;轻度AD患者组双侧海马、海马旁回、杏仁核、丘脑、额叶、颞叶、顶叶、枕叶皮质出现了灰质萎缩.aMCI与轻度AD患者组全脑白质FA值减低的模式与灰质萎缩模式不同.aMCI组与轻度AD组比较未发现具有统计学意义的FA值减低脑区.aMCI、轻度AD患者组全脑白质FA值与简易智能精神状态检查量表(MMSE)评分没有相关性.结论 基于体素的MR DTI全脑白质分析能够较全面、客观地揭示aMCI、轻度AD的脑白质损害的模式.aMCI、轻度AD患者白质损害的模式与灰质不同,提示脑白质病变是多种病理机制导致的.aMCI患者向轻度AD进展过程中,脑白质各向异性改变不显著,脑白质FA值的改变可能无法反映患者认知功能障碍的严重程度.

Abstract：

Objective To evaluate the microstructural integrity of white matter (WM) in patients with amnestic mild cognitive impairment (aMCI) and mild Alzheimer's disease (AD) using voxel-based analysis (VBA), and investigate the relationship between WM abnormalities and gray matter(GM) atrophy.Methods Thirty-three cases with aMCI, 32 cases with mild AD and 31 normal aging volunteers as control subjects were scanned on a 3.0 T MR system using diffusion tensor imaging (DTI) and three-dimensional spoiled gradient-recalled(3DSPGR) sequences. Fractional anisotropy (FA) maps and morphological images were preprocessed by SPM5 and voxel-based comparisons between the 2 patient groups and the control group were performed by t test. Results Relative to the control group, patients with aMCI showed significantly reduced FA value in bilateral frontal, temporal and left occipital WM, left anterior part of cingulum, left inferior parietal lobule, and the W M adjacent to the triangular part of the right lateral ventricle(k≥20 voxels).In mild AD,significantly reduced FA value was found in bilateral hippocampal,inferior parietal lobular,frontal,temporal,and occipital WM,bilateral corpus callosum,anterior part of cingulums,the WM adjacent to the triaangular part of the bilateral lateral ventricles,left temporal stem,left thalamus,right precuneus(k≥20 voxels).Significantly reduced GM volume was found in left hippocampus,parahippocampal gyrus,lingual gyrus and superior temporal gyrus,bilateral insulae and middle temporal gyri in aMCl group whencompared with control group(k≥50 voxels).In mild AD,significantly reduced GM volume was found in bilateral hippoeampi,parahippocampal gyri,amygdalae,thalami,temporal,parietal,frontal,occipital cortex(k≥50 voxels).The pattern of areas with reduced FA differs;from that of the GM volumetric reduction.No areas with significantlv reduced FA was detected in aMCl compared with mild AD. There was no significant correlation between FA value of WM in patient groups and Mini-Mental State Examination(MMSE)scores.Conclusions Voxel-based MRI DTI analysis of whole brain white matter can objectively reveal widespread white matter abnormalities in early-stage AD.The difierence between WM FA reduction pattern and GM volumetric reduction pattern indicates that the pathological WM changes in earlyslage AD were caused by multiple mechanisms. FA did not vary significantly in patients pr0gressing from aMCI to mild AD and can hardly reflect the severitv of cognitive function damage in these patients.     

经侧脑室后角灌洗与侧脑室前角穿刺引流对重症脑室出血疗效的比较研究

目的　探讨治疗脑室出血的有效治疗方法。方法　采用侧脑室后角穿刺引流、大量生理盐水灌洗治疗脑室出血 3 6例 ,并与同期单纯侧脑室前角穿刺引流治疗脑室出血 3 3例进行比较。结果　观察组 3 6例 ,显效 2 4例 ,有效 6例 ,无效 6例 ,死亡 6例 ,死亡率 16 7% ,有效率 83 .3 % ,对照组 3 3例 ,显效 18例 ,有效 1例 ,无效 6例 ,死亡 8例 ,死亡率 2 4.2 % ,有效率 5 7.6%。两组比较具有显著差异 ,P <0 .0 5。结论　侧脑室后角穿刺、灌洗治疗脑室出血简便易行、有效。     

Regional cerebral blood flow assessed with <Superscript>99m</Superscript>Tc-ECD SPET as a marker of progression of mild cognitive impairment to Alzheimer's disease

Patients diagnosed with mild cognitive impairment (MCI) have a higher risk of developing Alzheimer's disease (AD). However, not all such patients develop this kind of dementia. The purpose of this prospective study was to assess whether regional cerebral blood flow (rCBF) patterns measured with technetium-99m ethyl cysteinate dimer single-photon emission tomography (^99mTc-ECD SPET) in patients suffering from MCI are useful in predicting progression to AD. The study group comprised 42 patients who fulfilled MCI criteria according to the International Psychogeriatric Association and the Alzheimer's Disease Cooperative Study. rCBF was calculated in 16 regions of interest (ROIs). All patients were clinically assessed for 1–3 years. Twenty-one developed AD (group I) while the initial diagnosis of MCI was retained in the other 21 (group II). ROC curves were designed, and sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios were determined for each ROI. Compared with group II (MCI), group I (AD) showed a significant reduction of relative blood flow (RBF), ranging from 7% to 10%, in the following areas: right and left prefrontal, right and left frontal, right and left parietal, right and left temporal, right and left frontoparietotemporal and left posterior lateral temporal. Left prefrontal, left frontal and left parietal areas showed sensitivities and specificities higher than 75% and areas below the ROC curve close to 80%. This study shows that RBF patterns in the right and left prefrontal, right and left frontal and left parietal areas are sensitive early markers of progression towards AD. Reduction of rCBF in the medial temporal and anterior lateral temporal cortex has no value as a predictor since it also occurs in patients with MCI who remain stable.     

Ventricular enlargement in multiple sclerosis: a comparison of three-dimensional and linear MRI estimates

Atrophy of central white matter is related to irreversible clinical disability in multiple sclerosis (MS) and ventricular enlargement may be a sensitive marker of this tissue loss. Therapeutic trials in MS have provided MRI data for investigation of cerebral atrophy in MS. These studies use almost exclusively two-dimensional (2-D) images, which may be limited in the assessment of three-dimensional (3-D) structures. We used 3-D MRI data to estimate ventricular volumes in 40 patients with MS and 10 healthy controls, to look at associations with clinical disability and the stage of the disease. We then compared simple linear measures of ventricular size from conventional 2-D images, with 3-D volume estimates to establish the best available linear indices of ventricular volume. Mean ventricular volumes were increased in the patients and significantly larger in the more disabled patients. The estimated volume of the third ventricle obtained from 3-D MRI showed the strongest association with the clinical stage of the disease, duration of symptoms and levels of disability. Finally, we confirmed that in patients with MS accurate data on ventricular size can be obtained from 2-D images by two simple and convenient linear measures, the width of the third ventricle and of the anterior horn of the lateral ventricle. Received: 17 April 2000 Accepted: 25 August 2000     

Minimal asymmetry of the brain: a normal variant

Normal cerebral asymmetry, well-known to neuroradiologists, is not widely recognized by radiologists in general. In our review of CT brain scans, 31 of 300 patients with a negative neurologic examination and no history of birth injury, head trauma, or seizure had recognizable asymmetry of the frontal horns of the lateral ventricles. The right frontal horn and the right cerebral hemispheres were larger than the left twice as often as left were larger than right. The right frontal lobe was wider than the left in 44% of patients and extended as far anteriorly or more anteriorly than the left in 22% of patients. The right central hemispheric mass tended to be wider than the left, resulting in slight displacement of the pineal gland to the left, in approximately 45% of cases. The posterior end of the left Sylvian fissure projected farther posteriorly in 10% of the patients. Occipital petalia and a more posterior position of the calcified glomus of the choroid plexus of the lateral ventricle were both common on the left side of 56%. Earlier studies of the brain by other methods have also shown asymmetry. An awareness of these anatomic asymmetries in normal individuals should preclude the erroneous diagnosis of an atropic or mass lesion.