中枢神经系统结核的MRI诊断

目的：分析中枢神经系统结核的MRI表现,探讨MRI的诊断价值。方法：收集我院自2006年9月-2008年5月的中枢神经系统结核121例,其中颅内结核111例、椎管内结核10例。对所有病例均作常规MRI平扫,静脉注射Gd-DTPA增强,并对其MRI表现作回顾性总结。结果：脑膜结核60例、脑实质结核33例、脑膜并脑实质结核18例,脊膜结核4例、结核性脊髓炎4例、脊膜并脊髓结核2例,合并脑梗死24例、脑积水22例,合并室管膜炎3例、硬膜下积液1例、脊髓空洞4例。结论：MRI是检查中枢神经系统结核的重要和可靠方法。     

原发性中枢神经系统淋巴瘤的MRI诊断

目的 研究原发性中枢神经系统淋巴瘤(PCNSL)的MRI表现特点,提高对该病的诊断与鉴别诊断率.方法 回顾分析了12例经病理证实的原发性中枢神经系统淋巴瘤的MRI表现.结果 病灶T1WI多呈略低或等信号,T2WI呈等或略高信号;增强扫描多呈明显均匀强化,极少数呈环形强化,肿瘤坏死囊变少见,未见出血、钙化;瘤周水肿相对较轻,占位效应轻.结论 原发性中枢神经系统淋巴瘤MRI表现具有一定特征性,可做出较准确的诊断.     

中枢神经系统血管周细胞瘤的MRI诊断

目的：探讨MRI诊断中枢神经系统血管周细胞瘤（HPC）的价值,提高对本病的认识。方法：分析7例经手术病理证实为HPC的MRI表现。所有患者均行MRI平扫及增强扫描。结果：6例位于颅内,1例位于颈段椎管内。T1WI示肿瘤呈等信号或稍高信号,T2WI呈等信号或稍高信号,增强扫描肿瘤实体部分强化明显。在颅内病例中,4例病灶内有斑片状囊变或坏死区;4例显示有血管流空或强化血管影;5例有瘤周水肿;2例病灶部分跨过天幕。结论：中枢神经系统HPC的MRI表现有一定的特征,有一定的提示诊断,但需与脑膜瘤鉴别,要注意分析其恶性征象,以提高术前诊断的正确率。     

原发性中枢神经系统淋巴瘤的MRI表现

目的:描述原发性中枢神经系统淋巴瘤的MRI表现,探讨MRI对该病的诊断价值。材料和方法:回顾性分析10例经手术病理证实的原发性中枢神经系统淋巴瘤的MRI表现。结果:10例均为弥漫大B细胞型非霍奇金淋巴瘤。5例为单发,5例为多发,共16个病灶,其中大脑半球8个,基底节4个,右侧背侧丘脑及基底节1个,脑室内3个。10例病变均表现为局灶性肿块,6例边界较清楚,4例边界不甚清楚。T1WI呈稍低或等信号;T2WI呈等或稍高信号。增强扫描7例呈明显均匀强化,1例呈明显脑回样强化,1例中等度强化,1例(放疗后)无强化。2例有侧脑室室管膜线样明显强化。9例存在占位效应。3例瘤周重度水肿,5例瘤周中度水肿,2例瘤周轻度水肿。结论:原发性中枢神经系统淋巴瘤是一种较为罕见的原发性中枢神经系统恶性肿瘤,MRI是诊断该病的重要的无创性检查方法。当男性中老年患者发现颅内,特别是幕上深部脑白质及胼胝体、基底节区实性占位性病变,呈稍长或等T1、稍长或等T2信号,瘤周水肿及占位效应较轻,增强扫描呈明显均匀强化时,应考虑原发性中枢神经系统淋巴瘤的诊断。     

Primary central nervous system immunocytoma: MRI and spectroscopy

We report on a young woman with a primary cerebral immunocytoma. Most primary cerebral nervous system lymphomas (PCNSL) are highly malignant undifferentiated B-cell tumours, there are few data on the clinical course, MRI and spectroscopy findings of this rare PCNSL subtype. MRI revealed a radially enhancing tumour with mild perifocal oedema. MR spectroscopy indicated low cell turnover. Slow clinical progression, no significant changes with treatment, and imaging findings were consistent with a low-grade malignant tumour. Received: 21 January 2000/Accepted: 15 February 2000     

中枢神经系统黑色素瘤的MRI表现

目的:探讨中枢神经系统黑色素瘤的影像表现,以期提高认识.方法:搜集经手术病理证实的中枢神经系统黑色素瘤8例,对其影像学表现进行分析.8例均行MRI平扫和增强扫描,7例行扩散加权成像(DWI)扫描,4例行氢质子磁共振波谱(1 H-MRS)扫描,2例行磁共振灌注(PWI)扫描.结果:8例患者原发2例,分别位于脑膜以及脊膜;转移6例,均位于脑内,多接近脑表面.信号表现:典型的黑色素瘤3例,T1WI呈高信号、T2WI呈低信号,增强扫描明显强化,不典型黑色素瘤5例,信号表现多样,部分出现囊变坏死,增强扫描实性部分明显强化.DWI示除2例多发转移者表现为低信号外,其余5例均表现为高信号或混杂高信号.1 H-MRS表现:原发于脑膜者胆碱(Cho)峰明显增高,N-乙酰天门冬氨酸(NAA)峰缺失,并出现高耸的脂质(Lip)峰;3例脑内单发转移者Cho峰明显升高,NAA峰减低,出现不同程度升高的Lip峰.PWI表现:2例行灌注成像者均表现为高灌注.结论:中枢神经系统黑色素细胞肿瘤影像表现多样,与其黑色素含量、瘤内出血及坏死密切相关,综合分析临床和影像资料有助于提高诊断的准确性.     

中枢神经系统黑色素细胞肿瘤的MRI诊断

目的：探讨中枢神经系统黑色素细胞肿瘤的MRI特征。方法：回顾性分析16例经手术病理证实的中枢神经系统黑色素细胞肿瘤的临床资料及MRI资料,观察肿瘤MRI上的形态学特征及信号表现。结果：16例黑色素细胞肿瘤,男10例,女6例。年龄17～55岁。肿瘤位于颈段椎管内3例,额叶3例,颞叶2例,桥脑小脑角区1例,鞍区1例,小脑半球2例,脑内及脑膜多发者3例,全脑脊膜1例。肿瘤发生于颅底脑外者占17%,发生于近颅底脑实质者占43%。MRI信号特征典型者6例,不典型者10例,其表现为短T1等T2信号、或不均匀短T1等T2信号,或因瘤体卒中而呈囊实性混杂信号,增强扫描呈不均匀强化。结论：中枢神经系统黑色素细胞肿瘤可不具典型的MRI信号特征。对于发生于颅底及颈段软脊膜的有混杂T1或T2信号的肿瘤,在鉴别诊断时应考虑到该瘤的可能。     

原发性中枢神经系统淋巴瘤的磁共振成像表现

目的探讨原发性中枢神经系统淋巴瘤（PCNSL）的磁共振成像（MRI）特征及鉴别诊断。方法回顾性分析15例经手术病理证实的PCNSL的MRI表现。结果病理检查均为B细胞来源的弥漫性大B细胞性淋巴瘤。15例PCNSL19个病灶,单发13例（87％）,多发2例（13％）共6个病灶。病灶常位于脑表浅部位和近中线部位,T1wI呈等或稍低信号,T2WI及液体衰减反转恢复序列（FLAIR）呈等或稍高信号,弥散加权成像（DWI）呈高信号。所有病灶均明显强化,增强后病灶大多呈均匀实质团块状或结节状强化,典型的可出现“尖角征”、“握拳征”,3例可见小囊变,呈“硬环征”。结论PCNSL的MRI表现具有一定的特征性,术前MRI检查有助于诊断及鉴别诊断,结合患者影像学及临床资料,术前可作出明确诊断。     

中枢神经系统血管母细胞瘤的MRI诊断

目的:探讨MRI(常规及DWI等序列)在中枢神经系统血管母细胞瘤诊断中的应用价值。方法:对经手术病理证实的73例血管母细胞瘤共81枚病灶的MRI表现进行回顾性分析。结果:血管母细胞瘤多为单发(67/73),小脑为最常见发病部位(61/81),可分为3型:囊伴结节型53个,实质型22个,单纯囊型6个;DWI序列肿瘤结节及实质型瘤体均呈低信号;19个病灶表现有囊中囊征象。结论:血管母细胞瘤的MRI表现具有特征性,且与其病理基础密切相关,能为手术方式的选择提供依据。     

颅内原发性中枢神经系统淋巴瘤的MRI研究

目的研究颅内原发性中枢神经系统淋巴瘤（PCNSL）的MRI表现特点。资料与方法回顾性分析23例颅内PCNSL的MRI表现。抽取恶性胶质瘤30例、颅内转移瘤30例,共60例归为非PCNSL组作为对照。观察肿瘤部位、分布、信号、形态,并进行统计学分析。结果颅内PCNSL好发于深部脑组织,如胼胝体、丘脑及基底节区,多发病灶多呈区域性分布;肿瘤T2WI多呈等或稍高信号,甚至低信号,扩散加权像（DWI）呈均匀高信号;增强扫描多呈均匀明显强化,肿瘤周围可见“尖突征”。与非PCNSL组之间差异有统计学意义（P〈0．01）。结论颅内PCNSL影像表现多样,但具有一定特征。     

颅内原发性中枢神经系统淋巴瘤的MRI表现

目的研究颅内原发性中枢神经系统淋巴瘤（PCNSL）的MR／表现特点。方法回顾性分析8例经手术病理证实的原发性中枢神经系统淋巴瘤的MR／表现。结果8例均为弥漫大B细胞型非霍奇金淋巴瘤。3例为单发,5例为多发,共13个病灶,其中大脑半球8个,基底节区4个,右侧背侧丘脑及基底节区1个。8例病变均表现为局灶性肿块,T1WI呈稍低或等信号;T2WI呈等或稍高信号。增强扫描7例呈明显均匀强化,1例轻度强化。6例瘤周重度水肿,2例瘤周中度水肿。结论原发性中枢神经系统淋巴瘤较为罕见,MRI是诊断该病的重要的无创性检查方法。颅内PCNSL影像学表现多样,但具有一定特征。     

MRI in central nervous system infections: A simplified patterned approach

Recognition and characterization of central nervous system infections poses a formidable challenge to the neuro-radiologist. Imaging plays a vital role, the lesions typically being relatively inaccessible to tisue sampling. The results of an accurate diagnosis are endlessly rewarding, given the availability of excellent pharmacological regimen. The availability of numerous magnetic resonance (MR) sequences which provide functional and molecular information is a powerful tool in the hands of the radiologist. However, the plethora of sequences and the possibilities on each sequence is also intimidating, and often confusing as well as time consuming. While a large number of reviews have already described in detail the possible imaging findings in each infection, we intend to classify infections based on their imaging characteristics. In this review we describe an algorithm for first classifying the imaging findings into patterns based on basic MR sequences (T1, T2 and enhancement pattern with Gadolinium), and then sub-classify them based on more advanced molecular and functional sequences (Diffusion, Perfusion, Susceptibility imaging, MR Spectroscopy). This patterned approach is intended as a guide to radiologists in-training and in-practice for quickly narrowing their list of differentials when faced with a clinical challenge. The entire content of the article has also been summarised in the form of flow-charts for the purpose of quick reference.     

中枢神经系统白血病的CT及MRI主要表现

目的 分析经临床证实的11例中枢神经系统白血病的CT及MRI表现,探讨其影像学特征,增进对该病的认识,为临床诊断提供依据.方法 回顾性分析经临床证实的11例中枢神经系统白血病CT及MRI的影像学表现.其中4例CT平扫后行MRI平扫及增强扫描检查;其余7例直接行MRI平扫或平扫+增强扫描检查.结果 ①白血病浸润软脑膜5例,CT表现为脑沟、脑池消失,内可见条状低密度灶,对应MRI表现为T1WI呈低信号,T2WI/FLAIR呈高信号,脑回肿胀,DWI呈稍高信号,增强后明显强化;合并蛛网膜下腔出血1例.②脑实质浸润6例,单发肿块2例,余均为多发,MRI表现T1WI低信号,T2WI/FLAIR高信号,DWI高信号,无明显占位效应,增强后明显强化;其中3例合并出血.③硬脑膜受累1例,累及额部板障,CT表现为软组织密度灶,MRI表现为软组织信号灶,增强后明显强化.结论 中枢神经系统白血病影像学表现有一定的特征性,影像学检查尤其是MRI增强检查有助于对中枢神经系统白血病表现的认识,以及诊断及鉴别诊断.     

Primary angiitis of the central nervous system: serial MRI of brain and spinal cord

MRI findings in primary angiitis of the central nervous system (PACNS) are highly variable, ranging from normal to diffusely abnormal. We describe brain and spinal cord abnormalities in patients with PACNS and changes over time, to provide criteria which could be useful for differential diagnosis. We reviewed six patients, with a final diagnosis of PACNS, who underwent serial contrast-enhanced brain and spinal MRI. Follow-up ranged from 12 to 60 months. Brain MRI showed multiple small abnormalities in all patients, giving high signal on T2-weighted images, focal or diffuse, mainly in deep and subcortical white matter; four patients had both supra- and infratentorial lesions. On the initial MRI, in five patients, almost 90 % of the abnormal foci showed contrast enhancement. Virchow-Robin perivascular spaces were enlarged and simultaneously enhancing in four patients. Three patients also had spinal cord abnormalities, in the cervical and thoracic segments in two, and exclusively cervical segment in one. Two patients had brain biopsy-proven PACNS; in the remainder, the diagnosis of PACNS was presumptive, considering similarities in clinical and MRI features and MRI follow-up. On MRI, after steroid and immunosuppressive therapy, a significant decrease in the number and size of the abnormalities, enhancing and nonenhancing and of enhancing perivascular spaces was observed. Simultaneous enhancement of brain and spinal cord lesions and of perivascular spaces, at the onset of the disease, which resolves during follow-up, can therefore suggest PACNS. Received: 1 July 2000 Accepted: 21 November 2000     

Superficial siderosis in the central nervous system

We describe a rare entity, superficial siderosis of the central nervous system, due to multiple small episodes of subarachnoid haemorrhage from any source. Non-specific neurological findings are associated with deposition of ironcontaining pigments in the leptomeninges and superficial layers of the cortex. T2-weighted magnetic resonance imaging demonstrates characteristic low signal in the meninges.     

Diagnostic value of MRI in tuberculous meningitis

In this study 15 patients with clinical findings and positive cerebrospinal fluid analyses for tuberculous meningitis were evaluated with magnetic resonance imaging (MRI). Tuberculous meningitis was diagnosed in 11 cases when thick meningeal enhancement was present after intravenous injection of gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) in T1-weighted images. Intra-axial tuberculomas were present in 8 patients, 2 of whom had intra-axial tuberculomas without MRI evidence of meningitis. Tuberculomas showed ring or nodular enhancement in postcontrast T1-weighted images, but the most significant MR feature of intraparenchymal tuberculomas was the hypointense appearance of the lesions on T2-weighted images.Correspondence to: C. Tayfun     

中枢神经系统肠源性囊肿的MRI表现

目的:探讨中枢神经系统肠源性囊肿的MRI表现.方法:搜集经手术及病理最终确诊的23例肠源性囊肿患者并分析其MRI表现,所有患者均经MRI平扫,其中10例行MRI增强扫描,4例行DWI扫描.结果:23例肠源性囊肿患者中,3例发生在颅内,其中2例发生在左侧中颅窝,1例发生在桥前池,其余20例发生在椎管并且全部位于髓外硬膜下,其中颈段10例,胸段8例,腰段2例.MRI平扫大部分病灶T1WI呈等低信号,T2 WI呈高信号,部分病灶信号混杂;9例增强扫描囊液及囊壁均未见明确强化,1例见边缘强化;部分病例可见特征性“脊髓嵌入征”表现;DWI均未见明显扩散受限;2例伴脊椎发育异常.结论:肠源性囊肿的形态及MRI信号特点具有一定特征,结合临床症状、伴发体征有助于早期诊断.     

磁共振弥散张量成像在中枢神经系统的应用研究进展

磁共振弥散张量成像（MR-DTI）是一种新的无创性成像方法,它不同于常规T2加权成像和弥散加权成像（DWI）,它可以准确地反映水分子扩散的方向信息,并通过特殊的软件处理,能够实现白质的纤维跟踪与可视化,目前已经成为中枢神经系统临床应用和生命科学研究重要的工具,本文在近年来的文献基础上详述了弥散张量成像的基本原理,并对弥散张量成像在中枢神经系统各个方面的运用现状和研究进展做一综述。     

中枢神经系统狼疮的MRI表现(附三例报告及文献复习)

目的分析中枢神经系统狼疮的ＭＲＩ表现。材料与方法搜集了３例临床资料确诊为中枢神经系统狼疮的头颅ＭＲＩ片，复习了近几年国内外文献报告的中枢神经系统狼疮的ＭＲＩ表现。结果中枢神经系统狼疮的头颅ＭＲＩ表现为：（１）大脑、小脑半球深部白质、基底节区、脑干的异常信号灶，Ｔ１加权图像呈等或略低信号，Ｔ２ＷＩ呈高信号。（２）病灶往往为多发对称性，呈斑点状、条状、片状，周围无水肿带，无占位效应。其ＭＲＩ所见须与单纯性疱疹性脑炎、脱髓鞘病变、脑梗死等ＭＲＩ表现相鉴别。结论结合临床资料、ＭＲＩ可以诊断中枢神经系统狼疮。     

中枢神经系统Rosai-Dorfman病的CT和MRI表现

目的 总结中枢神经系统Rosai-Dorfman病(RDD)的CT和MRI影像特点,增加对该病的认识,减少临床误诊率.方法 结合文献回顾性分析4例病理确诊的中枢神经系统RDD患者的临床表现和影像特点.结果 2例患者行头颅CT平扫,4例患者行头颅MRI平扫加增强扫描;1例患者头颅CT显示脑水肿,1例头颅CT平扫未见异常;3例患者头颅MRI显示鞍区T1WI等或低信号,T2WI等或低信号,其中2例呈环形强化,1例呈均匀强化;1例患者右上颌窦、右鼻腔、右眶内及右颅前窝多发病灶,T1WI呈等和低混杂信号,T2WI呈等信号,呈团块样强化.4例患者病灶均基于脑膜生长.结论 临床发热、头痛、血沉增快,血免疫球蛋白升高的患者,如影像检查发现颅内基于脑膜或者脊膜生长的独立或者多发病灶,特别是鞍区的病灶,应考虑到中枢神经系统RDD的可能.