脑神经元移行异常的CT诊断

目的：研究脑神经元移行异常的CT表现及其诊断价值。材料和方法：回顾性分析1998-12—2006-06我院19例经CT诊断的脑神经元移行异常的CT表现特征。结果：19例中，灰质异位7例，CT表现为白质内结节样、块样或带样的异位灰质灶；脑裂畸形8例，CT表现为横贯大脑半球内衬有皮质的裂隙；巨脑回畸形3例。CT表现为脑回变宽变平、脑皮层增厚、脑白质减少；无脑回畸形1例。CT表现为脑表面光滑、脑回脑沟消失。结论：神经元移行异常为先天性畸形。CT有特征表现能做出诊断。     

神经元移行异常的MRI诊断

目的分析各种神经元移行异常的MRI特征。方法分析50例神经元移行异常的MRI表现,总结MRI影像特征。结果灰质异位23例,脑裂畸形12例,多小脑回9例,巨脑回5例,无脑回1例。脑灰质异位MR表现为皮质下,白质区,侧脑室室管膜下结节状、团块状或带状病灶,在所有序列上与正常脑灰质信号相同。脑裂畸形表现为大脑半球的横行裂隙,边缘衬有灰质。多小脑回畸形表现为脑回增多、细小而浅。巨脑回畸形表现为脑回增宽,灰质增厚,白质变薄。无脑回畸形表现为大脑半球呈肾形,正常脑沟和脑回消失,皮质增厚,白质变薄。结论MRI是诊断神经元移行异常的最佳影像方法。     

神经元移行异常的CT诊断(附30例报告)

目的:探讨神经元移行异常的CT表现特点,以进一步提高其诊断准确性。方法:回顾分析近两年经本院确诊的30例神经元移行异常病例的临床和CT资料,总结各类病变的CT表现特征。结果:30例中,灰质异位8例,脑裂畸形6例(其中5例伴多小脑回或巨脑回畸形,所有病例均伴透明隔缺如),多小脑回畸形或巨脑回20例(其中5例伴脑裂畸形),单侧巨脑畸形1例。灰质异位表现为白质内团块状、室管膜下结节状或条带状灰质密度灶;脑裂畸形表现为从侧脑室壁到脑表面贯穿大脑半球的裂隙,表面覆盖灰质,可分为开唇型和闭唇型;多小脑回或巨脑回表现为广泛或局限性的皮质增厚,边缘呈波浪状,灰白质交界光滑,脑沟浅,白质减少;单侧巨脑畸形表现为一侧大脑半球及颅腔增大。结论:CT能够良好显示脑神经元移行异常的病理特征,有助于临床准确诊断。     

神经元移行异常的3D-FSPGR评价

目的研究磁共振3D-FSPGR(fast spoiled gradient recalled)序列结合多平面重组分析对神经元移行异常评价的价值。方法回顾性分析30例神经元移行异常,采集常规SET1WI、FSET2WI和针对脑组织解剖的3D-FSPGR T1WI序列图像及多平面重组(MPR)。结果 30例神经元移行异常最终诊断包括15例多小脑回畸形、5例巨脑回畸形、1例无/巨脑回畸形、6例灰质异位以及3例脑裂畸形。单纯常规MRI诊断了21例典型神经元移行异常,9例不典型神经元移行异常在常规MRI上不能诊断,包括4例多小脑回畸形、4例室管膜下灰质异位及1例脑裂畸形合并有局灶性脑皮层发育不良。多小脑回畸形常规MR表现为局限性脑皮层欠自然,而在3DFSPGR上表现为局限性脑皮质增厚并浅小脑沟。室管膜下灰质异位常规MRI表现侧脑室形态欠自然,而在3DFSPGR上表现为侧脑室体后部旁、前角室管膜下类圆形灰质结节信号影。脑裂畸形合并局灶性脑皮层发育不良常规MRI表现为仅有脑裂畸形,而在3DFSPGR上表现为除脑裂畸形外,还有局限性脑灰白质分界欠清。结论 3D-FSPGR序列可以更好地显示不典型神经元移行异常的解剖结构,帮助其诊断和分类。     

脑神经元移行异常的CT表现及临床意义

目的：探讨脑神经元移行异常的ＣＴ表现,提高对脑神经元移行异常的认识。材料和方法：回顾分析１８例脑神经元移行异常病人的临床和ＣＴ资料。１５例做了平扫,３例平扫后做增强扫描。结果：无脑回畸形和／或巨脑回畸形４例,其主要ＣＴ表现为整个脑表面光滑或部分区域光滑、平坦,脑回、脑沟消失,脑皮层增厚,脑白质减少。脑裂畸形１１例,ＣＴ表现为大脑内出现横贯的裂隙,其壁由异位灰质组成,裂隙壁可以是融合型（Ⅰ型）或者是分离型（Ⅱ型）。灰质异位３例,ＣＴ表现为室管膜下或半卵园中心结节状或团块影,密度与脑灰质相似。本病以儿童多见,平均年龄１２．５岁。临床上常表现为顽固性癫痫。结论：脑神经元移行异常是一种先天性神经元迁移畸形,通过脑神经元移行异常的各种ＣＴ征象分析,对于临床正确诊断和合理治疗均有重要价值。     

神经元移行异常的MR诊断

神经元移行异常包括无脑回畸形,巨脑回畸形、多小脑回畸形、脑裂畸形、单侧巨脑症和灰质异位。无脑回畸形/巨脑回畸形:无脑回畸形指皮层脑回的缺如,但多数情况下,或多或少都有一小区域的脑回存在。这些宽、扁和浅的脑回叫巨脑回畸形。无脑回畸形和巨脑回畸形的脑皮层包括分子层、外细胞层、细胞稀疏层和内细胞层。细胞稀疏层是神经元移行期间,由于脑代谢障碍而引起的层状坏死区。神经元移行通过此层可受到损害。此外,已经移行的神经元,其轴突和树突在坏死层中断,并发生退变。由于在移行过程中,移行细胞中断移行,因而脑皮层变厚;与此相反,轴突和树突的减少,导致了脑白质变薄。MRI可清楚显示灰—白质比例倒置,T_2像可见增厚的皮层内有一高信号强度的边缘带,即细胞稀疏层。无脑回畸形多位     

脑神经元移行异常的MRI诊断

目的:报导38例脑神经元移行异常并总结本病MRI特点.材料和方法:38例小儿脑神经元移行异常患者.年龄3个月～14岁.主要临床表现为癫痫11例,智力减退17例,运动障碍16例.采用Toshiba 0.35T超导型MRI系统以自旋回波T1加权(T1WI)500/25ms及T2加权(T2WI)2000—4000/80ms,横断面及矢状面平扫,层厚5—10mm.结果:MRI特点:l)巨脑回/无脑回畸形20例.其中以无脑回为主者10例,表现额叶仅有几个扁平、粗大的脑回,顶枕叶脑表面光滑,无沟回显示.皮层增厚,白质变薄.以巨脑回为主者10例,主要表现脑回增宽,脑沟变浅.2)脑裂畸形16例.7例裂隙一端融合,9例裂隙分离.合并透明隔缺如者9例,合并多小脑回畸形者3例.3)灰质异位9例.孤立性2例,合并巨脑回/无脑回者3例,脑裂畸形者4例.结论:脑神经元移行异常MRI检查有典型征象,在本病诊断中起重要作用.     

脑神经元移行异常的CT诊断

脑神经元移行异常包括脑裂畸形、灰质异位、无脑回畸形、巨脑回畸形、多小脑回畸形等。临床主要表现为难治性癫痫、智能发育不全等。在CT、MR问世以前脑神经元移行异常诊断是靠病理学，现主要依靠CT和MR检查诊断。国内文献报导不多，本文对4例脑神经元移行异常的临床及CT资料并结合有关文献对其进行分析讨论。     

局灶性脑皮层发育不良的MRI诊断

目的 研究局灶性脑皮层发育不良(focal cortical dysplasia,FCD)的MRI表现特点.资料与方法 回顾性分析23例经手术病理证实的FCD患者的MRI表现.常规行横断位、矢状位及垂直于海马长轴的斜冠状位扫描,获得T1 WI、T2WI及液体衰减反转恢复序列(FLAIR)图像.结果 23例FCD病灶均表现为一侧大脑半球内局限性病变.病灶区域皮质增厚18例,灰白质分界模糊20例,皮层下白质异常信号22例,脑回、脑沟形态异常14例,邻近蛛网膜下腔局限性扩大4例.T1WI、T2WI及FLAIR显示灰白质分界模糊分别为6例、20例及18例;皮层下白质异常信号分别为3例、16例及19例;脑回、脑沟形态异常分别为12例、10例及11例.结论 FCD的MRI表现为皮质增厚、灰白质分界模糊、皮层下白质异常信号、脑回、脑沟形态异常及邻近蛛网膜下腔局限性扩大.T2WI及FLAIR显示灰白质界限、白质内异常信号较T1WI敏感,T1WI显示脑回、脑沟形态有一定的价值.     

神经元移行异常与癫痫

目的：探讨常见神经元移行异常的MRI表现与临床症状。资料与方法：搜集14例各种神经元移行异常的病例，分析其MRI表现与相应临床症状。结果：14例神经元移行异常者中灰质异位9例，其中皮层下灰质异位1例，皮层下带状灰质异位1例，室管膜下灰质异位7例；无脑回－巨脑回畸形5例，其中弥漫性4例，局限性1例。各种神经元移行异常病变的临床症状以癫痫最常见，临床表现一般与病变的范围和位置有关。结论：神经元移行异常虽然并不常见，但在癫痫的病因中起重要的作用，应引起人们的重视。     

Nonlissencephalic cortical dysplasias: correlation of imaging findings with clinical deficits.

PURPOSE: To establish correlations between MR patterns and clinical outcome in patients with nonlissencephalic cortical dysplasias. PATIENTS AND METHODS: MR and clinical data from 36 patients with cerebral cortical gyral anomalies (other than classical type I or type II lissencephaly) were retrospectively reviewed. RESULT: The five patients with diffuse cortical dysplasia, including two with congenital infections, had microcephaly and severe development delay from a very early age. Infantile spasms occurred in three of the five. Focal areas of cortical dysplasia were most common in the frontal lobes, but were seen in all areas of the brain. The most common MR appearances were 1) a thickened, irregularly bumpy cortex with shallow, wide sulci, and 2) a deep infolding of thickened cortex. The twelve patients with bilateral focal dysplasia had a high incidence of bilateral motor dysfunction (67%), delayed speech (67%), and generalized developmental delay (92%). When the dysplasia was unilateral, contralateral spastic hemiplegia or monoplegia was present in 14 of 19 patients (74%), but dysphasia was uncommon, even in patients with dysplasia in the frontal lobe of the dominant hemisphere. CONCLUSION: Surgical resection of focal areas of cortical dysplasia in patients with medically refractory seizures is becoming more common, and the neuroradiologist will play an increasingly important role in the initial diagnosis and delineation of these anomalies.     

Analysis of the cerebral cortex in holoprosencephaly with attention to the sylvian fissures

BACKGROUND AND PURPOSE: Analysis of specific features in the brain of patients with holoprosencephaly (HPE) may clarify normal and abnormal brain development and help predict outcomes for specific children. We assessed sulcal and gyral patterns of cerebral cortex in patients with HPE and developed a method of grading brain development. METHODS: Neuroimaging studies (75 MR imaging, 21 CT) of 96 patients with HPE were retrospectively reviewed, with specific attention paid to the cerebral cortex. Thickness of cortex, width of gyri, and depth of sulci were assessed subjectively and by measurement. The angle between lines drawn tangential to the sylvian fissures ("sylvian angle") was measured in each patient with HPE and in 20 control patients. RESULTS: Thickness of cortex was normal in all 96 patients. Gyral shape and width and sulcal depth were normal in 80 patients. Twelve patients, all with very severe HPE and microcephaly, had reduced sulcal depth, diffusely in eight and limited to the anteromedial cortex in four with lobar HPE. Four patients had subcortical heterotopia, located anterior to the interhemispheric fissure, associated with shallow sulci in the overlying cortex. Sylvian fissures were displaced further anteriorly and medially as HPE became more severe, until, in the most severe cases, no sylvian fissures could be identified. Sylvian angle measurements corresponded closely with severity of HPE, being largest in the most severe and smallest in the least severe cases. All patients with HPE had sylvian angles significantly larger than the mean of 15 degrees measured in the control patients. CONCLUSION: The only true malformations of cortical development were subcortical heterotopia. However, diffuse and focal abnormal sulci were observed. We propose our sylvian angle measurement of extent of frontal lobe development as an objective means of quantifying the severity of HPE.     

Central nervous system hypoxia in children due to near drowning

Fourteen children who experienced acute, profound central nervous system hypoxia secondary to near drowning, aspiration, or respiratory arrest underwent CT examination. During the first week after the episode, the most frequent finding was a loss of gray-white matter differentiation. Other findings included effacement of sulci and cisterns, focal areas of edema in the cerebral cortex or basal ganglia, and hemorrhagic infarctions of the basal ganglia. Subsequent CT scans obtained from two weeks to five months after the hypoxic episode showed progression of cerebral loss from cortical infarction with gyral hemorrhage and enhancement to global parenchymal atrophy. The prognosis is poor in these patients: seven children experienced severe neurologic deficits and seven died.     

中枢神经系统白血病CT诊断

目的:探讨中枢神经系统白血病的CT表现,提高诊断水平。方法:总结经临床脑脊液细胞学检查找到白血病细胞共计17例CT表现,其中急性淋巴细胞白血病10例,急性非淋巴细胞白血病7例。CT平扫17例,增强扫描13例。结果:CT表现为脑池、沟消失,脑皮层区低密度,增强扫描呈斑片状及脑回样强化3例。脑实质内呈结节状及肿块状高密度影,周围伴水肿14例,增强扫描呈明显均匀强化。结论:结合临床,CT对中枢神经系统白血病诊断有帮助。     

外部性脑积水的CT表现与鉴别诊断

目的:获取外部性脑积水的CT特征,并与脑萎缩、硬膜下积脓、积液相鉴别,从而提高其诊断准确性。材料与方法:选择外部性脑积水49例,脑萎缩21例,硬膜下积脓5例,硬膜下积液2例,分析其CT表现特征,并与临床对照。结果:1.外部性脑积水CT特征:额及顶区蛛网膜下腔增宽。前部纵裂及大脑外侧裂增宽,额、顶区脑沟增宽、深陷,其他部正常,侧脑室可轻度扩大或正常,大脑额、顶叶凸面皮质无变薄征象。2.脑萎缩CT特征:大脑沟普遍增宽、深陷,有时小脑沟也增宽及其数目增多(≥4条),第三、四脑室及侧脑室扩大,纵裂增宽且不局限于前部,大脑凸面皮质变薄,蛛网膜下腔增宽且不局限于额顶区。3.硬膜下积脓CT特征:颅内板下方新月形低密度区,密度高于脑脊液,大脑凸面受压,变平、内移,于新月形低密度与大脑凸面之间有一薄膜结构,呈膜状飘浮征象,侧脑室可有受压变窄。4.硬膜下积液CT特征:一侧或双侧新月形低密度影,为脑脊液CT值。脑凸面有受压略变平征象,单侧硬膜下积液可有中线结构移位,侧脑室可有轻度变窄。结论:只要熟悉外部性脑积水、脑萎缩、硬膜下积脓,以及硬膜下积液各自的CT特征,一般不难对它们作出鉴别诊断。     

脑裂畸形的CT、MRI影像学征象分析

目的 探讨脑裂畸形的CT、MRI特征性表现及其临床诊断价值.方法 回顾性分析17例脑裂畸形患者的临床CT、MRI的影像学征象.结果 17例脑裂畸形患者的CT、MRI图像表现为自皮质至侧脑室的横跨大脑半球的裂隙,裂隙两旁为内折的灰质;裂隙内侧端多为脑室外壁的幕状突起,闭合型裂隙外侧端呈小喇叭或深脑沟样形态,开放型裂隙内外侧端呈哑铃状.17例脑裂畸形患者中,单侧12例、双侧5例,共有24个裂隙;闭合型12例、开放型5例;合并透明隔缺如10例、灰质异位8例、一侧丘脑和部分基底节缺失2例、多小脑回畸形4例、巨脑回畸形1例、侧脑室三角区白质较少2例、蛛网膜囊肿5例.结论 脑裂畸形具有特征性的影像学表现,CT、MRI检查能够清楚地显示脑裂畸形的病理解剖形态.     

Focal pachygyria with unusual vascular anomaly

Summary A case of focal pachygyria with an unusual vascular anomaly is reported. Preoperative magnetic resonance imaging demonstrated few and broad gyri, and an abnormally thickened cortex of the right frontal lobe. In addition, T2-weighted imaging showed a high intensity lesion beneath the thickened cortex. In the pachygyric cortex, the peripheral portions of the arteries were tortuous and irregularly dilated, and prominent deep medullary veins were found draining into the subependymal veins. Histological examination revealed a decreased number of neurons with no tendency towards lamination, and degenerative changes with gliosis in the white matter. These findings suggest that the etiology of this anomaly may be gradual perfusion failure restricted to the territory of the anomalous vessels through the period of neuronal migration to the post-migratory, perinatal stage.     

脐尿管癌的CT诊断

目的:探讨脐尿管癌的螺旋CT表现特点,提高对本病的认识。方法:回顾性分析7例经手术病理证实的脐尿管癌的螺旋CT表现,包括肿块的部位、形态、大小及增强表现。结果:7例病理均为腺癌或黏液腺癌。CT均表现为脐尿管与膀胱交界区大小不等的软组织肿块,5例肿块同时向腔内外生长,1例腔内生长为主,1例肿块主要位于腔外。肿块形态不规则,6例伴有周围膀胱壁受侵增厚。1例肿块内见多个斑点状钙化。增强扫描5例呈不均匀强化,2例强化均匀,7例静脉期均明显强化。结论:脐尿管肿瘤有其独特的发生部位,影像表现典型,术前CT检查能够做出准确定位与定性诊断。