粘多糖贮积症的颅脑CT及MRI表现

目的:探讨粘多糖贮积症的颅脑CT及MRI表现特征.方法:对经临床和实验室检查确诊为粘多糖贮积症的6例患者行颅脑CT及MRI扫描,分析其影像学表现.6例患者均行CT平扫,其中2例行CT增强扫描;6例患者中4例行MRI检查,其中1例行增强扫描.结果:CT平扫6例中4例显示两侧大脑半球白质内散在低密度灶,增强后病灶未见强化;1例仅见脑室扩大,1例未见异常.MRI检查4例中2例显示脑实质多发小囊状信号由脑室边缘向各脑叶呈放射状分布,脑白质病变呈斑片状长T1、长T2信号,增强后所有脑内病灶均未见强化;1例脑室扩大,白质减少;1例仅显示脑白质信号异常.MRI还显示3例齿状突发育不良伴周围软组织增厚,2例颅颈结合区硬脑脊膜增厚伴椎管狭窄.本组1例行脑组织活检,电镜显示神经元内有空泡状包涵体及斑马体.结论:粘多糖贮积症的颅脑CT及MRI表现有一定特征,可在一定程度上为临床诊断、估计病损程度、监察病变进程及选择治疗方案提供依据.     

神经纤维瘤病I型的颅脑CT及MRI评价

目的：认识神经纤维瘤病I型的颅脑影像学表现，评价MRI和CT在诊断方面的价值。材料和方法：回顾性分析11例经临床确诊神经纤维瘤病患者的CT和MRI图像，同时查阅近年国内外相关研究资料，提出神经纤维瘤病I型的主要颅脑影像学表现及有关病理解释。结果：CT、MRI显示眼眶周围丛状神经纤维瘤6例，其中5例伴蝶骨翼发育不良，1例伴视神经增粗。11例中MRI显示苍白球T2WI高信号8例，其中4例表现为TlWI等信号，2例T1WI高信号，2例T1WI低信号，所有病例增强扫描均无强化。而CT扫描仪2例显示低密度。此外，MRI显示丘脑、小脑半球、脑干T2WI高信号各2例，CT无异常。结论：神经纤维瘤病I型有明显特征性颅脑改变，在显示基底节及脑白质病变方面MRI比CT更具优越性。     

MRI of cortical dysplasia – correlation with pathological findings

Cortical dysplasia (CD) is the most epileptogenic structural lesion associated with epilepsy and patients with intractable seizures caused by this condition are good surgical candidates. MRI plays an important role in detecting the abnormalities of CD. We clarified the MRI characteristics of CD by comparing imaging and histological findings in 20 patients with intractable seizures who underwent surgical resection. There were 12 males and eight females, mean age at operation was 15 years. MRI was performed at 1.5 tesla; T1-weighted, T2- and proton density-weighted spin-echo and fluid-attenuated inversion-recovery (FLAIR) images were obtained. The lesions were in the frontal lobe in nine cases, temporal in two, occipital in another two, insular in one and multilobar in six. Blurring of the grey/white matter junction was seen in all patients, and T2 prolongation in white matter and/or at the grey/white matter junction in 19. Abnormal signal intensity was more frequent in the white matter or at the grey/white matter junction than in the grey matter. FLAIR images made this abnormal high signal easier to appreciate, and we thought them very useful in this context. In areas of T2 prolongation, we saw dysplastic neurones and/or balloon cells, dysmyelination, and ectopic neuronal clustering histologically; glial proliferation played an important role in prolonging T2. Received: 24 November 2000/Accepted: 6 February 2001     

Myelographic features of mucopolysaccharidoses: a new sign.

A new mechanism of myelopathic changes in patients with mucopolysaccharidosis is described. Two similar cases had myelographic evidence of marked concentric impingement of the cervical subarachnoid space and cord compression due to thickening of the dura. Myelography is indicated in the evaluation of these patients because surgical decompression may reverse the progressive neurological deficits.     

Hypertrophic cranial pachymeningitis: assessment with CT and MR imaging

Three patients with diffuse idiopathic cranial pachymeningitis with predominant involvement of the tentorium and falx are reported. Progressively increasing headaches were the usual symptoms, along with ataxia and various cranial nerve palsies. CT in all cases and MR imaging in two cases detected isolated thickened dura mater. In one case, MR depicted dural involvement as a very large, hypointense area with fine hyperintense edges on T2-weighted images. Microscopic examination of thickened dura revealed extensive fibrotic tissue with a chronic inflammatory infiltrate containing lymphocytes, plasma cells, and scattered eosinophils; these findings closely paralleled the MR features. Only four cases with similar pathologies have been described, all before the advent of CT and MR. We discuss the different causes of thickened dura mater as well as the significance of the fact that dural thickening can be responsible for occlusion of the dural sinuses. Cranial pachymeningitis is a rarely reported disease that can resemble other disorders associated with tentorial thickening; CT and MR can help differentiate it from these other disorders.     

局限性脑皮层发育不良的影像与病理对比分析

目的 探讨局限性脑皮层发育不良(FCD)的影像改变,并与病理改变对比,以提高对FCD的认识.方法 回顾性分析28例经临床病理证实的FCD患者的临床及影像资料,所有患者均行MR检查,其中14例患者行PET检查,将影像改变与病理变化进行对比分析.结果 28例FCD中MRI显示病灶24例(85.7%),4例未显示明显异常,局限性脑皮层增厚及灰、白质界限不清是FCD的主要MR改变,同时脑皮层及皮层下白质可出现多种异常信号,其中皮层下白质内类三角形稍长T2信号指向侧脑室具有一定的特征性.14例行PET检查,其中9例(64.3%)显示病灶局部葡萄糖代谢活性减低.病理改变主要包括脑皮层细胞排列结构紊乱,皮层及皮层下白质内异形神经元细胞及气泡状细胞,部分患者可见皮层下白质髓鞘形成障碍及海绵样坏死灶.结论 高质量的MR图像可以显示大部分FCD病灶,包括脑皮层及皮层下白质的异常信号,是目前术前评价FCD的最佳影像检查.     

Melanotic neuroectodermal tumour of infancy at the anterior fontanelle

We describe a 4-month-old girl presenting with a melanotic neuroectodermal tumour of infancy at the anterior fontanelle. According to the neuroimaging findings, this tumour was found to lie epidurally, adherent to the dura mater, with thickening of the adjacent frontal bone. The tumour was dense on CT, while MRI showed a major part of the tumour to be isointense with cerebral cortex on both T1- and T2-weighted images. The neuroimaging and clinical features are briefly discussed. Received: 18 December 1997 Accepted: 22 June 1998     

不同病理类型局灶性皮质发育不良的MRI特征

目的 总结局灶性皮质发育不良(FCD)的MRI特征性表现,探讨不同病理类型FCD各自的特异性MRI征象.方法 回顾性分析经病理证实的44例FCD患者的MRI表现.将44例患者根据病理检查结果分为FCD Ⅰ型和Ⅱ型,观察以下MRI征象在两种类型中的出现情况:(1)局灶性皮层增厚;(2)灰、白质分界不清;(3)液体衰减反转恢复(FLAIR)序列和(或)T2WI上白质内向脑室方向延伸的锥形异常增高信号;(4)脑叶发育不全;(5)FLAIR上灰质信号强度增高;(6)T2WI上灰质信号强度增高;(7)FLAIR上皮层下白质信号强度增高;(8)T2WI上皮层下白质信号强度增高;(9)T1WI上皮层下白质信号强度减低.2组间的比较采用χ2检验及校正χ2检验.结果 44例FCD患者中FCD Ⅰ型30例,FCDⅡ型14例.共32例患者MRI表现异常,灰、白质分界不清为最常见征象(23例).其中FCD Ⅰ型患者中MRI表现异常者21例,特征性表现为脑叶发育不全11例,FCDⅡ型脑叶发育不全0例,两种类型间差异有统计学意义(连续性校正χ2=5.0286,P=0.0249).FCDⅡ型患者中MRI表现异常者11例,特征性表现为局灶性皮层增厚10例,FCD Ⅰ型为11例(χ2=4.6234,P=0.0315);FLAIR上白质信号增高9例,FCD Ⅰ型为7例(χ2=6.9180,P=0.0085);白质内向脑室方向延伸的锥形异常增高信号4例,FCD Ⅰ型为0例(连续性校正χ2=6.2883,P=0.0122);差异均有统计学意义.其他征象两种类型间差异无统计学意义.结论 不同病理类型FCD的MRI表现各有特点,了解这些特点有助于不同病理类型FCD的早期诊断和术前评估.     

Intracranial Fibroxanthoma in an Infant: a Case Report

A primary fibroxanthoma of the central nervous system is very rare. We present a case of an infantile fibroxanthoma that arose from the cranial dura mater in a six-month-old girl with US, MRI and PET/CT features that mimicked a meningioma. The tumor appeared as a large, well-circumscribed echogenic mass in the right parieto-occipital area on US. The tumor was seen as isoattenuated to slightly hypoattenuated on pre-contrast CT scan and as hypometabolic on PET/CT. As seen on T2-weighted image, the mass was heterogeneously hyperintense to the gray matter. The mass was isointense on T1-weighted image and homogeneously strongly enhanced on contrast enhanced T1-weighted image.     

中枢神经系统白血病影像诊断

目的:回顾性分析经临床证实的7例中枢神经系统白血病的CT和MRI表现,提高对该病的诊断水平.方法:中枢神经系统白血病7例均是男性,急性淋巴细胞白血病3例,急性髓性白血病3例,慢性粒细胞白血病急性变1例.5例患者CT平扫后行MRI检查;其余2例患者未作CT扫描,直接行MRI平扫及增强检查.结果:①白血病浸润软脑膜3例,其...     

Spinal dural involvement in Erdheim-Chester disease: MRI findings

There are very few reported cases of Erdheim-Chester disease that document involvement of dura at the level of the spinal cord. Among these reports, we know of no publication that includes detailed MRI findings. To the best of our knowledge, the case presented here is the first published report of this specific manifestation of Erdheim-Chester disease that includes detailed MRI findings in addition to the related history. Spinal manifestations of Erdheim-Chester disease in our patient were at the dorsal and lumbar levels (T1-T6 and T12-T11 respectively). Both epidural and subdural linear large masses were present, causing spinal cord compression at the dorsal level and epidural thickening at the lumbar level.     

局灶性脑皮质发育不良的扩散张量成像初步研究

目的 探讨DTI技术诊断局灶性脑皮质发育不良(FCD)的价值.方法 回顾性分析12例FCD患者的临床、MRI及DTI等资料.DTI经过图像后处理,获得平均扩散系数(MD)和部分各向异性分数(FA)图及彩色编码张量图,于FCD的皮质下白质区及对侧相应皮质下白质区设置椭圆形ROI,测量每个ROI的MD及FA值.病灶侧与对侧MD、FA值的比较采用配对t检验.扩散张量纤维束示踪成像(DTT)以T_2 WI图像为参照,ROI设置同DTI,以ROI中的任一点作为种子点,获得通过该ROI区域的所有白质纤维束示踪图像.结果 12例患者MR平扫均显示局灶性脑皮质增厚及灰白质界限不清,其中7例显示皮质下白质稍长T_1、稍长T_2信号,2例皮质下白质萎缩,3例皮质下白质无明显异常.DTI分析显示FCD邻近皮质下白质与对侧比较FA值明显下降(患侧0.31±0.05,对侧0.42±0.08,t=-3.995,P<0.01),MD值明显上升[患侧(1.02±0.16)×10~(-3)mm~2/s,对侧(0.86±0.13)×10~(-3) mm~2/s,t=2.655,P<0.05],差异均有统计学意义.DTT显示10例FCD患者皮质下白质纤维束较对侧明确减少,2例较对侧可能减少,主要表现为皮质下白质纤维稀疏,与深部白质纤维间联系减少.结论 FCD除了导致脑皮质结构异常外,也影响局部皮质下白质纤维的发育,DTI是常规MR检查的重要补充.     

Clinical and Neuroradiological Aspects of the Different Types

Abstract The different types (I–VII) of mucopolysaccharidoses (MPS), a hereditary lysosomal storage disorder where the enzyme defect leads to glycosaminoglycan deposits in different tissues, present with characteristic lesions of the central nervous system (CNS). This review reports the CT and MRI findings of patients suffering from mucopolysaccharidosis in the context with aspects of biochemistry, pathophysiology, histological findings and clinical course. Neuroradiological findings include hydrocephalus, focal or global brain atrophy, and spinal cord compression at the atlantoaxial joint. Cribriform white matter lesions, corresponding to mucopolysaccharide deposition in the enlarged perivascular space, combined with leukencephalopathy are found in about half of the patients. Another half of the patients show minor to severe myelopathy at the atlantoaxial joint due to cervical cord compression. These findings are observed mainly in patients with MPS type IV, but as well in nearly all patients with MPS type VI. In the literature brain involvement is described exclusively in MPS type I, II and III, but the authors show definite demyelination and widening of the perivascular space in a number of patients with MPS type VI, who additionally suffered from progressive visual deficits, caused by ocular and/or optic nerve involvement.      

MRI of focal cortical dysplasia

We studied nine cases of focal cortical dysplasia (FCD) by MRI, with surface-rendered 3D reconstructions. One case was also examined using single-voxel proton MR spectroscopy (MRS). The histological features were reviewed and correlated with the MRI findings. The gyri affected by FCD were enlarged and the signal of the cortex was slightly increased on T1-weighted images. The gray-white junction was indistinct. Signal from the subcortical white matter was decreased on T1- and increased on T2-weighted images in most cases. Contrast enhancement was seen in two cases. Proton MRS showed a spectrum identical to that of normal brain. Received: 10 September 1997 Accepted: 6 January 1998     

累及皮层的脑内外肿瘤MRI定位诊断

目的 评价MRI征象在累及皮层的脑内外肿瘤定位诊断中的价值。资料与方法 对累及皮层的27例颅内脑外肿瘤和13例脑内肿瘤进行回顾性分析，比较两组脑肿瘤MRI征象的统计学差异。结果 脑外肿瘤与脑内肿瘤之间有鉴别意义的MRI征象为瘤内出血、骨质破坏、白质塌陷征、包膜及硬膜尾征。肿瘤形态、囊变坏死、血管流空和水肿情况对于定位诊断无统计学意义。结论 通过各种定位征象的综台分析可以提高皮层区脑肿瘤定位诊断的准确性。     

驱肠虫药相关脑病的MRI和CT研究

目的 描述驱肠虫药相关脑病的MRI和CT表现。方法 回顾性分析20例临床确诊的驱肠虫药相关脑病的影像特征,MRI检查10例,MRI及CT检查6例,CT检查4例;1例行脑穿刺活检。结果 MRT1WI病变呈低信号,T2WI呈高信号,6例增强扫描5例无强化,其表现可分4种类型：13例病变呈多发斑片状,多位于侧脑室周围中、后方区域白质;1例病变T1WI呈同心圆状改变,病理示神经细胞广泛空泡变性;1例病变呈斑片状螺及双侧海马区皮髓质;另1例T2WI示半球白质信号广泛增高并累及基底节核团。10例CT均示白质区多发斑片状低密度灶,4例增强扫描无强化。所有病变均无占位效应。结论 驱肠虫相关脑病的影像表现类似脱髓鞘病变或散发性脑炎,病理检查未发现脱髓鞘改变。     

Dural metastases from prostate carcinoma: A systematic review of the literature apropos of six patients

Intracranial metastases are a rare manifestation of prostate carcinoma and the dura mater is the most affected site. We report a series of six patients with dural prostate metastases (DPM) and perform a systematic review of the current literature in order to depict imaging trademarks of this condition. This review points to a magnetic resonance imaging (MRI) pattern of meningeal involvement characterized by a diffuse smooth thickening, nodular appearance or dural-based masses. We also demonstrate an osteoblastic pattern of lesions, particularly in sphenoid wing, by computed tomography (CT) scans. We suggest that these imaging findings may support an elevated index of suspicion of DPM in elderly men, including those patients without urologic symptoms.     

Spinal epidural haematoma: report of 11 cases and review of the literature

Spinal epidural haematomas (SEH) are rare; most are caused by trauma, anticoagulant therapy, vascular anomalies, hypertension, blood dyscrasias, epidural anaesthesia or, rarely, spinal surgery. We report 11 cases and review the literature (16 cases). The clinical picture is that of acute spinal cord compression. MRI characteristics are quite specific. On sagittal sections, the SEH appears as a biconvex mass, dorsal to the thecal sac, clearly outlined and with tapering superior and inferior margins. The dura mater is seen as curvilinear low signal separating the haematoma from the cord. Within 24 h of onset, the haematoma is isointense with the cord on T1-weighted images and heterogeneous on T2-weighted images. Later, it gives high signal on both T1- and T2-weighted images. Differential diagnosis must include subdural haematoma, epidural neoplasm and abscess. Complete neurological recovery rapidly follows laminectomy and removal of the clot. In three of our cases, the haematoma resolved spontaneously. MRI is the best examination for diagnostic and follow-up.     

Cortical tubers without other stigmata of tuberous sclerosis: imaging and pathological findings

There is immense variability in the clinical presentation of tuberous sclerosis and many incomplete forms (formes frustes) exist. To investigate the imaging characteristics of cortical tubers seen in tuberous sclerosis unaccompanied by other stigmata, we reviewed MRI and CT of six patients who met the criteria for a definitive diagnosis of TS, established solely by the presence of a histologically confirmed cortical tuber. Five of the patients had a solitary cortical tuber and the last had three lesions, one of which was resected and confirmed histologically. The other two lesions were included in our study. CT showed five tubers as low density, but three were not identified. No calcified or dense lesions were observed. MRI revealed peripheral components and inner cores of seven cortical tubers in five patients, with differing signal characteristics. The subcortical cores, with T1 and T2 prolongation, were separated from the overlying cortex. Abnormal inhomogeneous high signal was observed in both the cortex and subcortical white matter on proton-density weighted or FLAIR images. A radially orientated white-matter band was observed in one patient, and central depression of the expanded gyri in another. In one patient, a cortical tuber was atypical, with a thick cortex on T1-weighted images and a blurred grey/white matter junction with diffusely increased signal on T2-weighted images. Cortical tubers without other stigmata of tuberous sclerosis are shown to be distinct from focal cortical dysplasia. Received: 18 September 1998 Accepted: 27 November 1998     

Contrast-enhanced magnetic resonance imaging of sub- and epidural empyemas

Summary Contrast-enhanced magnetic resonance images (MRI) of three patients with subdural (SDE) and two with epidural empyemas (EDE) were reviewed. In each case, the capsule of the lesion demonstrated enhancement, and distinction between capsule and contents was obvious on contrast-enhanced images. In SDE, contrast-enhanced images clearly depicted thickening of the neighbouring dura mater and a co-existent brain abscess. In EDE, part of the displaced dura mater did not enhance, which facilitated differentiation from SDE. Contrast-enhanced MRI was thus of value in diagnosis.