Differential effects of age and sex on the cerebellar hemispheres and the vermis: a prospective MR study.

PURPOSEThe purpose of this study was to determine the effects of age and sex on the size of the cerebellar hemispheres, the cerebellar vermis, and the pons in healthy adults.METHODSWe estimated the volumes of the cerebellar hemispheres (excluding the vermis and the peduncles), the cross-sectional area of the vermis, and the cross-sectional area of the ventral pons from MR images obtained in 146 healthy volunteers, 18 to 77 years old.RESULTSWe found a mild but significant age-related reduction in the volume of the cerebellar hemispheres and in the total area of the cerebellar vermis; however, the analysis of age trends in the vermian lobules revealed differential age-related declines. The areas of lobules VI and VII and of the posterior vermian lobules (VIII-X) declined significantly with age, whereas the anterior vermis (I-V) showed no significant age-related shrinkage. The volume of the cerebellar hemispheres (especially the right) and the area of the anterior vermis were greater in men, even after adjustment for height. Neither age nor sex affected the area of the ventral pons.CONCLUSIONSNormal aging of the cerebellum is associated with selective regional shrinkage. The cerebellar hemispheres and the area of the anterior vermis may be larger in men than in women regardless of differences in body size.     

Age and sex differences in the cerebellum and the ventral pons: a prospective MR study of healthy adults.

BACKGROUND AND PURPOSE: The human brain exhibits a complex pattern of differential aging. The purpose of this study was to examine whether age differences in the volume of cerebellar regions and the ventral pons are differential or generalized, whether the age-related shrinkage is linear or exponential, and whether there are sex differences in the size of the cerebellum and pons. METHODS: The volumes of the cerebellar hemispheres (excluding the vermis and the peduncles), the vermis, and the ventral pons were estimated from the prospectively acquired MR scans of 190 healthy volunteers (aged 18-81 years). The relation between regional volumes, age, and sex was assessed while taking into account differences in body size (height). RESULTS: We found a moderate age-related reduction in the volume of the cerebellar hemispheres and the cerebellar vermis. In contrast to previous findings that suggested differential vulnerability of the posterior vermis, the age-related shrinkage of the vermian lobules was uniform-about 2% per decade. In accord with all reports in the literature, the size of the ventral pons was unrelated to age. The volume of the cerebellar hemispheres, the vermis, and the ventral pons were larger in men, even after adjustment for height. The magnitude of the sex difference was the largest in the hemispheres and the anterior vermis, and the smallest in the lobules VI-VII (declive-folium-tuber). CONCLUSION: Moderate age-related shrinkage of the cerebellum and lack of age-related differences in the ventral pons are robust phenomena. However, in all likelihood, the effects of age on the cerebellum are not differential but uniform. The cerebellum and the pons are larger in men than in women and the difference is especially pronounced in the cerebellar hemispheres and the anterior vermis.     

The cerebellum's role in reading: a functional MR imaging study

BACKGROUND AND PURPOSE: Long considered to have a role limited largely to motor-related functions, the cerebellum has recently been implicated as being involved in both perceptual and cognitive processes. Our purpose was to determine whether cerebellar activation occurs during cognitive tasks that differentially engage the component processes of word identification in reading. METHODS: Forty-two neurologically normal adults underwent functional MR imaging of the cerebellum with a gradient-echo echo-planar technique while performing tasks designed to study the cognitive processing used in reading. A standard levels-of-processing paradigm was used. Participants were asked to determine whether pairs of words were written in the same case (orthographic processing), whether pairs of words and non-words rhymed with each other, respectively (phonologic assembly), and whether pairs of words belonged to the same category (semantic processing). Composite maps were generated from a general linear model based on a randomization of statistical parametric maps. RESULTS: During phonologic assembly, cerebellar activation was observed in the middle and posterior aspects of the posterior superior fissure and adjacent simple lobule and semilunar lobule bilaterally and in posterior aspects of the simple lobule, superior semilunar lobule, and inferior semilunar lobule bilaterally. Semantic processing, however, resulted in activation in the deep nuclear region on the right and in the inferior vermis, in addition to posterior areas active in phonologic assembly, including the simple, superior semilunar, and inferior semilunar lobules. CONCLUSION: The cerebellum is engaged during reading and differentially activates in response to phonologic and semantic tasks. These results indicate that the cerebellum contributes to the cognitive processes integral to reading.     

The cerebellum in sagittal plane--anatomic-MR correlation: 1. The vermis

Correlation of thin (5-mm) sagittal high-field (1.5-T) MR images of three brain specimens and 11 normal volunteers with microtome sections of the human cerebellar vermis and hemispheres demonstrates that proton-density-weighted (long TR/short TE) and T2-weighted (long TR/long TE) spin-echo pulse sequences provide the greatest contrast between gray and white matter. These images also can display (1) the corpus medullare and primary white-matter branches to the vermian lobules, including the lingula, centralis, culmen, declive, folium, tuber, pyramis, uvula, and nodulus; and (2) several finer secondary branches to individual folia within the lobules. Surface features of the vermis including the deeper fissures (e.g., preculminate, primary, horizontal, and prepyramidal) and shallower sulci are best delineated by T1-weighted (short TR/short TE) and T2-weighted images, which provide greatest contrast between CSF and parenchyma. Given that the width of the normal vermis varied from 6 to 12 mm in our volunteers, the acquisition of thin slices (less than or equal to 5 mm) was required to minimize volume averaging of the cerebellar hemispheres with the vermis on a midline sagittal MR section. Knowledge of the detailed normal anatomy of the cerebellar vermis on sagittal MR images can assist in the identification of various pathologic alterations.     

Gait and cognitive abnormalities are associated with regional cerebellar atrophy in elderly fallers – A pilot study

ObjectivesTo investigate cerebellar lobule atrophy patterns in elderly fallers (EFs) and their association with gait and cognitive performance.BackgroundCognitive impairments, gait, and balance deficits are major risk factors for falls in older adults, however, their neural fingerprints remain poorly understood. Recent evidence from neuroimaging studies highlight the role of the cerebellum in both sensorimotor and cognitive networks, suggesting that it may contribute to fall risk.MethodsFourteen EFs (mean age ± SD = 78 ± 1.5 yrs.) and 20 healthy controls (HCs) (mean age ± SD = 69.6 ± 1.3 yrs.) underwent a 3 T MRI scan obtaining 3D T1-weighted images, cognitive, and gait assessments. Cerebellar lobule segmentation was performed, and the obtained cerebellar lobules volumes were adjusted for intracranial volume (ICV). The relationship between lobules volumes, gait, and cognitive performance scores was assessed using hierarchical multiple linear regression adjusted for age and gender.ResultsEFs exhibited lower cerebellar volumes in the posterior cerebellum, lobules V, VI, VIIB, VIIIA, VIIIB, and Crus II, and significantly higher volumes in the anterior cerebellum and lobule IV (p = 0.018 and p = 0.046) compared to HCs. In EFs, lobule V, VI, VIIB, VIIIA, VIIIB, and anterior cerebellum volumes were found to be independent predictors of usual walking (UW) gait speed, dual-task (DT) gait speed, mini Best, MOCA, CTTa, and CTTb (p < 0.05).ConclusionsThe observed patterns of cerebellar lobule atrophy and their associations with motor and cognitive performance scores suggest that cerebellar atrophy contributes to the pathophysiology of fall risk in EFs.     

小脑蚓部肿瘤的CT诊断(附95例分析)

目的：提高小脑蚓部各肿瘤ＣＴ诊断的正确性。材料与方法：９５例经手术,病理证帝物小脑蚓部肿瘤,男性５９例,女性３６例,术前均行ＣＴ平扫及增强扫描。结果：成神经管细胞瘤４１例,ＣＴ平扫以略高、等或略低混杂密度米,增强后肿瘤可均匀或不均匀强化。星形胶质瘤２９例,ＣＴ平扫以略低、低混杂密度米,增强后可轻度、不规则强化。致这膜瘤１０例,平扫以等、混合密度为主,增强多有均匀强化,常伴脑积水。或血管细胞瘤９例,     

Computed tomography in congenital ocular motor apraxia

Summary Unusual computed tomographic findings were observed in four patients with congenital ocular motor apraxia (COMA). These (CT) findings were characteristic in the posterior cranial fossa, with a dilated or deformed shape and size of the fourth ventricle, particularly its upper portion. One case revealed partial agenesis of the cerebellar vermis. It was suggested that the four patients subjected to CT showed abnormal topography of the cerebellar vermis or the brain stem. We postulate that these CT findings in COMA may have an important role in its pathogenesis.     

The cerebellum: 3. Anatomic-MR correlation in the coronal plane

Thin (5-mm) coronal high-field (1.5-T) MR images of four human brain specimens and 14 normal volunteers were correlated with myelin-stained microtomic sections of the specimen cerebella. The primary white-matter tracts innervating several hemispheric (posterior quadrangular, superior, and inferior semilunar, gracile, biventer, tonsil) and vermian (declive, folium, tuber) lobules are oriented perpendicularly to the coronal plane of section and are shown well on proton-density-weighted (long TR/short TE) and T2-weighted (long TR/long TE) spin-echo images, which provide excellent contrast between gray and white matter. Several of the surface sulci and fissures of the cerebellar hemispheres (including the superior posterior, horizontal, secondary, and posterolateral fissures) also course perpendicular to the coronal plane and are depicted well on T1-weighted (short TR/short TE) and T2-weighted images, which maximize contrast between CSF and parenchyma. The opportunity for side-to-side comparison of the hemispheres is a distinct advantage of the coronal view. Nevertheless, more obliquely oriented surfaces (preculminate, primary, inferior posterior, inferior anterior, and intrabiventral fissures) and deep hemispheric structures (primary white-matter tracts to central, anterior quadrangular, and floccular lobules) may be obscured by volume-averaging in the coronal plane; moreover, much of the finer anatomy of the vermis is depicted poorly. The constant surface and deep anatomy of the cerebellum revealed on coronal images in normal volunteers encourages detailed mapping. MR imaging in the coronal plane should be especially useful in identifying, localizing, and quantifying normal and abnormal morphologic differences between the cerebellar hemispheres.     

The cerebellum: 3. Anatomic-MR correlation in the coronal plane

Thin (5-mm) coronal high-field (1.5-T) MR images of four human brain specimens and 14 normal volunteers were correlated with myelin-stained microtomic sections of the specimen cerebella. The primary white-matter tracts innervating several hemispheric (posterior quadrangular, superior, and inferior semilunar, gracile, biventer, tonsil) and vermian (declive, folium, tuber) lobules are oriented perpendicularly to the coronal plane of section and are shown well on proton-density-weighted (long TR/short TE) and T2-weighted (long TR/long TE) spin-echo images, which provide excellent contrast between gray and white matter. Several of the surface sulci and fissures of the cerebellar hemispheres (including the superior posterior, horizontal, secondary, and posterolateral fissures) also course perpendicular to the coronal plane and are depicted well on T1-weighted (short TR/short TE) and T2-weighted images, which maximize contrast between CSF and parenchyma. The opportunity for side-to-side comparison of the hemispheres is a distinct advantage of the coronal view. Nevertheless, more obliquely oriented surfaces (preculminate, primary, inferior posterior, inferior anterior, and intrabiventral fissures) and deep hemispheric structures (primary white-matter tracts to central, anterior quadrangular, and floccular lobules) may be obscured by volume-averaging in the coronal plane; moreover, much of the finer anatomy of the vermis is depicted poorly. The constant surface and deep anatomy of the cerebellum revealed on coronal images in normal volunteers encourages detailed mapping. MR imaging in the coronal plane should be especially useful in identifying, localizing, and quantifying normal and abnormal morphologic differences between the cerebellar hemispheres.     

The secondary pulmonary lobule: normal and abnormal CT appearances

The secondary pulmonary lobule is a unit of lung supplied by three to five terminal bronchioles and contained by fibrous septa. High-resolution CT is able to show features of the secondary lobule, including interlobular septa, terminal bronchioles, and pulmonary arteries within a bronchiolovascular bundle. Because interstitial diseases have been shown to affect different components of the secondary lobule, high-resolution CT was used to compare the appearance of the normal secondary lobule with the abnormal secondary lobule in three patients with interstitial diseases primarily affecting lymphatic channels: lymphangitic carcinomatosis, sarcoidosis, and lymphangioleiomyomatosis. In lymphangitic carcinomatosis, the bronchiolovascular bundles and interlobular septa were thicker than those seen in a normal subject. In sarcoidosis, the interlobular septa and bronchiolovascular bundles were also thicker than normal. However, fibrosis caused distortion of the normal polygonal shape of the secondary lobule, not seen in either the normal subject or the patient with lymphangitic carcinomatosis. Lymphangioleiomyomatosis was characterized by multiple cysts within secondary lobules, often obliterating the normal polygonal appearance.     

正常与异常肺小叶高分辨率CT的初步研究

本文对16个正常肺叶标本进行了HRCT扫描并与相应的标本切面进行了对照,分析了50例正常成人胸部CT和HRCT征象。结果表明,正常肺小叶呈边缘不规则的多边形结构,每边长约7～22mm,小叶间隔厚约0.1～1.0mm。在HRCT上,小叶间隔呈直线状或光滑的曲线状,小叶核和小叶间隔之间呈均一的低密度区。分析了21例弥漫性肺疾病的HRCT征象,特发性肺纤维化小叶间隔增厚,小叶结构变形,小叶间隔与肺组织交界面不清楚。肺淋巴道转移癌亦见小叶间隔增厚,但与肺组织交界面清楚,无小叶结构变形,间隔内可见结节,小叶间隔内多发的结节排列呈“串珠状”,此征高度提示肺转移癌。     

髓母细胞瘤的CT和MRI诊断

目的：提高非典型髓母细胞瘤的CT和MRI的诊断准确率。材料和方法：经手术及病理证实的髓母细胞瘤40例，年龄5～35岁。CT检查34例，其中28例同时作增强扫描。MRI检查38例，30例作增强扫描。32例同时作CT和MRI检查。结果：CT和MRI对髓母细胞瘤的定位诊断正确率为100％，定性诊断正确率为87．5％（35／40）。肿块位于小脑蚓部25例，小脑半球9例，四脑室内6例。肿瘤囊变26例，钙化3例，有例增强不明，3例出现转移，转移沿脑脊液播散。结论：非典型髓母细胞瘤可以发生在四脑室内，小脑半球，可以出现大的囊变、钙化，也可以增强不明显，掌握这些征象是CT和MRI诊断非典型髓母细胞瘤的关键。     

Intralobular distribution of oleic acid-induced pulmonary edema in the pig. Evaluation by high-resolution CT

The objective of this study was to elucidate the features of experimentally induced pulmonary edema at the lobular level, using high-resolution CT (HRCT) with pathological correlation. We selected the pig as the experimental animal because the pig has well-defined pulmonary lobules. Twelve Yorkshire pigs were included in this study. Five animals were used for studying normal anatomy of the pig lung. Pulmonary edema was induced by oleic acid infusion in 7 pigs. All computed tomographic (CT) scans were performed on a GE 9800 scanner, using 1.5 mm slice-thickness, 16 cm field of view with 512 X 512 matrix and bone reconstruction algorithm. The animals were killed after CT scans and the lungs were removed, inflated, fixed and dried, and subsequently sliced in sections which corresponded to the CT sections. Using CT images, specimen radiography, and histology, we studied the intralobular distribution of pulmonary edema in selected lobules of each animal. Oleic acid infusion caused multifocal hemorrhagic pulmonary edema within the pulmonary lobule. The distribution was uneven and areas surrounding the lobular bronchi were less involved. HRCT permits evaluation of morphological changes of oleic acid-induced pulmonary edema at the lobular level. The intralobular distribution of the lesions may provide additional information about the mechanism of permeability pulmonary edema.     

Dandy－Walker综合征的CT诊断（附七例报告）

笔者报告７例Ｄａｎｄｙ－Ｗａｌｋｅｒ综合征，均经ＣＴ检查后确诊，其中６例手术证实，２例有手术后ＣＴ复查。Ｄａｎｄｙ－Ｗａｌｋｅｒ综合征主要病理基础是第四脑室顶盖部的发育异常。此征的ＣＴ表现有惊人的相似性，它们是：（１）小脑蚓部缺失；（２）第四脑室从缺失的蚓部向后上方扩张，可呈羹袋状、扇形、三角形、（３）小脑半球向前外方分离退缩，两侧可不对称；（４）天幕上抬，窦汇及债窦升高，后颅凹扩大；（５）幕上脑室系统一般呈对称性扩张。笔者还报告了第四脑室从后囱门疝出和脑室内出血极为罕见的ＣＴ表现。     

CT and MR imaging findings in adults with cerebellar medulloblastoma: comparison with findings in children.

The goal of this study was to determine if certain imaging features suggest the diagnosis of cerebellar medulloblastoma in adults and to determine how often the classic CT appearance seen in children is present in adults. The study included 28 adult patients with proved cerebellar medulloblastoma. The tumor was located in the cerebellar vermis in 14 patients and in a cerebellar hemisphere in 14 patients. Thirteen patients had unenhanced CT of the brain, all patients had contrast-enhanced CT, and eight patients had unenhanced MR imaging. The imaging features in adults were compared with those in children, as described in the literature. In our adult patients, all tumors were hyperdense compared with gray matter on unenhanced CT and showed a slight to moderate increase in density after injection of contrast medium. Thirteen lesions had well-defined margins, and 15 had poorly defined margins. Low-density areas consistent with cystic and necrotic degeneration were detected in 23 (82%) of the 28 tumors. By comparison, in children, medulloblastoma usually originates in the vermis. As in adults, the mass is hyperdense on unenhanced CT, but enhances markedly and homogeneously after injection of contrast medium. Usually no evidence of cyst formation or necrosis is seen, and the tumor margins are well defined. This classic CT appearance of medulloblastoma in children was identified in only three (11%) of the 28 adult patients. Medulloblastoma has a variable MR appearance in both children and adults. On T2-weighted images, lesions are hypo-, iso-, or hyperintense compared with normal gray matter. The CT findings of medulloblastoma in adults usually differ from those of medulloblastoma in children. The tumor has a variable and nonspecific appearance in adults and should always be considered in the differential diagnosis of a mass in the posterior fossa.     

Joubert syndrome: a clinico-radiological study

Summary A characteristic malformation of the cerebellum, including dysgenesis of the vermis and enlargement of the fourth ventricle was observed on computed tomography (CT) in 16 children on review of our consecutive material. Seven of these children underwent magnetic resonance imaging (MRI) which showed hypoplasia of the brainstem in addition to cerebellar vermian dysgenesis. One child had, in addition, dysgenesis of the corpus callosum. All these children were developmentally delayed, and many had neonatal breathing abnormalities, congenital retinal dystrophy and supranuclear ocular motor abnormalities. Joubert's syndrome should be suspected in children in whom dysgenesis of the cerebellar vermis and hypoplasia of the brainstem is shown on CT or MRI.     

胎儿小脑蚓部发育的MRI研究

目的:描述正常胎儿标本小脑蚓部在不同孕周的正常发育生长曲线,并探讨胎儿丹迪-沃克综合征(DWS)的MRI表现。方法:对63例胎龄15～40周的胎儿标本行3.0T MRI扫描,从中选出52例符合要求的进行测量,扫描序列为T1WI、T2WI;扫描方位:矢状位扫描为主,辅以冠状位及横轴位;观察及测量内容:测量小脑蚓部的前后径(正中矢状面第四脑室顶点至水平裂处蚓部后缘最大距离)、上蚓高度及下蚓高度(上蚓的最高点及下蚓的最低点分别到前后径线的垂直距离)。对上述测量结果与孕龄间作回归分析。然后对6例经MRI诊断为DWS的病例进行回顾性分析。结果:小脑蚓部前后径、上蚓高度及下蚓高度分别与孕龄呈线性正相关,而上蚓高度总是略大于下蚓高度(P<0.05),多数标本正中矢状面T1WI、T2WI可清晰显示原裂及下后裂。DWS主要表现为小脑蚓部缺如或发育不良,测量数据小于正常胎儿,第四脑室与后颅窝囊肿相通或小脑延髓池增宽。结论:MRI可明确显示正常胎儿小脑蚓部在17孕周以后的正常发育表现及变化规律,而DWS的MRI表现具有特征性,MRI是诊断DWS最理想的影像学方法。     

Neuroradiological findings in the carbohydrate-deficient glycoprotein syndrome

The carbohydrate-deficient glycoprotein syndrome is a newly recognised genetic disorder characterised by mental retardation, liver disfunction during infancy, cerebellar ataxia and atrophy, polyneuropathy, growth retardation, stroke-like episodes, and the appearance of carbohydrate-deficient fractions of multiple glycoproteins in the serum. The neuroradiological findings have been known as features of olivopontocerebellar atrophy. However, whether the abnormalities in the cerebellum and brain stem progress after birth is not known. We have carried out serial CT and MRI on three Japanese patients with this syndrome at different ages. A small cerebellum, with peculiar enlargement of the cisterna magna, and a small brain stem are present in infancy and atrophy of the anterior vermis and from before backwards in the cerebellar hemispheres seem to progress throughout early childhood.     

Medulloblastoma in children: CT and MRI findings

Our purpose was to determine whether medulloblastoma (MB) shows specific neuroradiological features which may be employed in differential diagnosis from other common posterior cranial fossa tumours in childhood. Preoperative MRI was performed on 20 children with MB, and preoperative CT in 17 of them. All underwent surgery and histopathological diagnosis. There was a constant relationship between high density on CT and low signal on T1-weighted images. Signal behaviour on T2-weighted images and the degree of contrast enhancement were more variable. Most tumours arose in the midline, from the cerebellar vermis, involving the fourth ventricle, but hemisphere and extra-axial neoplasms were also seen. The combination of high density on CT and low signal on T1-weighted images is highly suggestive of MB and may assist preoperative differential diagnosis from other posterior cranial fossa tumours.     

Computed tomography in management of medulloblastomas

Summary The neuroradiological studies of 116 patients with histologically verified medulloblastomas, which had been examined with plain and contrastenhanced computed tomography (CT), were reviewed. The typical CT appearances of a well-defined, hyperdense enhancing mass in the vermis, with surrounding oedema, occurred in 60% of this series. Atypical features include calcification (17%), cystic or necrotic regions (47%) or poorly defined margins and lack of enhancement (7%). Such features in a vermis mass presenting in the first decade, especially in a boy, should not be considered against the diagnosis of medulloblastoma, but may be misleading when the tumour predominantly involves a cerebellar hemisphere.