脑室外神经细胞瘤的MRI诊断

目的探讨脑室外神经细胞瘤(extraventricular neurocytoma,EVN)MRI特征,提高对该肿瘤的认识。资料与方法回顾性分析6例EVN的MRI表现,并结合文献研究其MRI特征。结果6例均经手术及病理证实。肿瘤位于额叶3例,其余3例分别位于顶叶、颞叶及鞍区;肿瘤呈类圆形者边界清楚,形态不规则者境界不清;肿瘤实性或囊实性,实性多见,T1WI呈等或稍低信号,T2WI呈稍高信号,其间夹杂等、低或高信号,可提示钙化、流空血管、出血或囊变坏死,液态衰减反转恢复序列(FLAIR)呈高信号为主的混杂信号;囊实性者,实性部分信号同实性肿瘤,囊性部分呈长T1、长T2信号,信号较均匀;瘤周水肿无或轻;增强后呈轻-中度不均匀强化;占位效应轻。结论EVN的MRI表现具有一定特征性,MRI平扫及增强扫描有助于其诊断。     

低度恶性子宫内膜间质肉瘤的MR I诊断

目的：探讨低度恶性子宫内膜间质肉瘤(LGESS)的 MRI特点,提高对其诊断的准确性。方法回顾性分析经手术病理证实的4例LGESS病例的临床及MRI资料。全部病例均行MRI平扫。结果4例均表现为子宫不同程度的增大。病变直径5~12.1 cm,平均9 cm。3例位于宫腔内并累及子宫肌层,呈实性,结合带中断或消失,其中1例侵及膀胱、右侧输尿管、右侧输卵管及右侧卵巢;1例位于子宫肌层内,呈囊性,可见分隔和清晰的边界。3例实性肿瘤 MRI平扫表现为 T1 WI等信号,T2 WI稍高信号,1例信号欠均匀,其内及边缘可见增粗流空血管影;1例囊性肿瘤 MRI平扫表现为 T1 WI低信号,T2 WI高信号,内分隔呈低信号。3例合并子宫肌瘤,1例伴盆腔淋巴结转移。结论子宫内膜间质肉瘤好发于宫腔内,少数发生于子宫肌层,肿瘤多呈实性,也可呈囊性,多向子宫肌层浸润生长,肿瘤于T1 WI呈等或低信号,T2 WI呈高信号,信号可不均匀,其在 MRI 上有一定的特点,能为该病的正确诊断提供帮助。     

中枢神经细胞瘤的MRI诊断与鉴别诊断

目的 探讨中枢神经细胞瘤(central neurocytoma,CNC)的MR特点及诊断.方法 回顾性分析经手术病理证实的10例CNC的MRI表现.结果 8例CNC位于侧脑室,与透明隔粘连.其中男性6例,女性2例,年龄21～45岁,平均29.9岁.这些肿瘤在T1WI上均呈等低信号,在T2WI与DWI上呈不均匀高信号.8例病灶均可见囊性变,2例可见出血,2例可见蜂窝样改变,4例可见蛇形的匍行性血管流空征.此外,6例可见由胼胝体和侧脑室顶壁呈网状或丝条状垂向下的瘤组织.7例患者在增强MRI扫描后表现为不均匀性强化.另外2例患者病灶位于颈髓内,是脑室外中枢神经细胞瘤(extraventricular neurocytomas,EVN).男女各1例,年龄分别为27、37岁.其主要MRI表现包括:明显囊性变,T1WI上呈等低信号,T2 WI上呈不均匀高信号以及明显强化等.结论 脑室内CNC在MRI影像上有一定特征性,合理应用其影像学的特征性表现,有助于对CNC及其他侧脑室内肿瘤进行诊断及鉴别诊断.但颈髓内的EVN缺乏特异性的MRI表现,其诊断依靠病理学检查.     

脑室外神经细胞瘤的MRI表现

目的:探讨脑室外神经细胞瘤(EVN)的MRI特征性表现,提高对此病的认识。方法:回顾性分析经手术病理证实的7例EVN的临床及MRI检查资料,结合文献总结其MRI特点。结果:7例中2例病灶位于额叶,1例位于顶叶,2例位于中脑,1例位于松果体,1例位于颈髓。MRI T1WI示肿瘤呈不均匀低信号或等信号,T2WI及FLAIR图像上呈不均匀高信号,可见多发囊变,瘤周伴(3例)或不伴(4例)水肿,2例可见出血,呈片状或点状;增强扫描示病变实质部分呈絮状不均匀强化(4例)或不强化(1例),囊变区呈环形强化。结论:EVN的发生部位和MRI表现多种多样,MRI检查有助于诊断,但确诊仍需依靠病理检查。     

MRI manifestations of extra-ventricular neurocytoma

目的:探讨脑室外神经细胞瘤(EVN)的MRI特征性表现,提高对此病的认识.方法:回顾性分析经手术病理证实的7例EVN的临床及MRI检查资料,结合文献总结其MRI特点.结果:7例中2例病灶位于额叶,1例位于顶叶,2例位于中脑,1例位于松果体,1例位于颈髓.MRI T1 WI示肿瘤呈不均匀低信号或等信号,T2 WI及FLAIR图像上呈不均匀高信号,可见多发囊变,瘤周伴(3例)或不伴(4例)水肿,2例可见出血,呈片状或点状;增强扫描示病变实质部分呈絮状不均匀强化(4例)或不强化(1例),囊变区呈环形强化.结论:EVN的发生部位和MRI表现多种多样,MRI检查有助于诊断,但确诊仍需依靠病理检查.     

神经细胞瘤的MRI表现及鉴别诊断

目的探讨神经细胞瘤患者临床及MRI特征,旨在进一步提高其术前诊断的准确性。方法回顾性分析我院2009年1月至2014年1月收治的29例经手术及病理证实的神经细胞瘤患者的临床资料和MRI信号特点,所有病例术前均行MRI常规及增强扫描,其中3例中枢神经细胞瘤(CNC)和1例脑室外神经细胞瘤(EVN)行DWI检查,2例CNC行MRS检查。结果 29例神经细胞瘤中,CNC 21例,病灶均位于侧脑室内,其中19例位于Monro孔区,2例位置偏后附于透明隔;肿瘤呈浅分叶状团块,信号不均匀,T1WI多呈等或稍低信号,T2WI多呈等或稍高信号,FLAIR像呈高信号,3例DWI呈高信号,21例边缘或内部出现信号与脑脊液相近的囊变,13例肿瘤内部或边缘可见流空血管影,10例肿瘤边缘可见"绳索征"。EVN 8例,病灶位于大脑半球3例,小脑4例,脊髓1例;7例为囊实性,1例为实性,T1WI多呈等信号,T2WI呈高信号,1例有出血,1例有流空血管影;29例神经细胞瘤FLAIR像上实质部分均呈高信号,增强扫描均有不均匀强化。结论中枢神经细胞瘤有一定的影像学特点,结合患者发病年龄、病变位置可提高本病的确诊率,对于EVN,囊实性且实质部分FLAIR像及DWI上呈高信号应想到此病的可能,但其影像学特点仍需总结,确诊仍需病理检查。     

非典型性脉络丛乳头状瘤的MRI表现

目的探讨非典型性脉络丛乳头状瘤(atypical choroid plexus papilloma,ACPP)的MRI表现。方法收集经我院病理证实的4例非典型性脉络丛乳头状瘤,结合相关文献分析其MRI表现。结果 4例非典型性脉络丛乳头状瘤中,2例位于右侧脑室,均呈囊实性改变,实性部分T1WI呈稍低信号,T2WI呈稍高信号,增强后实性肿块、囊壁及分隔呈明显强化;1例位于第四脑室,1例位于右侧桥小脑角区,均呈实性肿块,T1WI呈稍低信号,T2WI呈稍高信号,增强后肿块呈中-重度均匀强化。结论位于侧脑室的ACPP具有一定的特点,MRI能够显示ACPP与脉络丛的关系,有利于术前诊断。     

原发性输卵管癌的磁共振征象分析

目的:探讨原发性输卵管癌(PFTC)的MRI影像特征.方法:回顾性分析15例经手术及病理证实的原发性输卵管癌的临床资料和MRI表现,总结其MRI影像特征.结果:病灶表现为附件区肿块,单侧14例,双侧1例.9例为囊实性肿块,其中6例肿块呈腊肠形,3例呈不规则形;5例伴不同程度输卵管积水;8例囊性成分于T1WI呈低信号、T2WI呈高信号;1例囊性成分于T1WI、T2WI均呈高信号;实性成分均呈T1WI等或低信号、T2WI不均匀高信号.4例为实性肿块,其中2例呈腊肠形,1例呈卵圆形,1例呈不规则形;呈T1WI低信号、T2WI稍高信号.2例为管状囊性肿块伴管壁乳头状软组织结节,囊液呈T1WI低信号、T2WI高信号,管壁结节呈T1WI稍低信号、T2WI稍高信号.增强后各种实性成分呈明显不均匀强化.伴腹水5例、直肠转移性肿块1例.结论:附件区腊肠形囊实性肿块伴输卵管积水或腊肠形实性肿块是输卵管癌较具特征性的MRI征象.     

松果体区实性肿瘤影像诊断分析

【摘要】目的：探讨松果体区实性肿瘤的CT及MRI影像特点及诊断要点。方法：搜集本院43例松果体区实性肿瘤的CT及MRI资料，生殖细胞瘤经手术病理及临床放疗后随访证实，其余病例均经手术病理证实。结果：生殖细胞瘤25例（手术病理证实18例，临床放疗后随访证实7例）；松果体实质细胞肿瘤10例；神经上皮源性肿瘤4例；脑膜瘤4例。生殖细胞瘤表现为圆形或类圆形肿块，边界清楚，密度/信号均匀，CT呈等或稍高密度，钙化的松果体被肿瘤包裹或位于肿瘤周边；MRI呈T1WI等低信号，T2WI等/稍低信号，增强扫描明显均匀强化。松果体细胞瘤表现为松果体区圆形或类圆形、浅分叶、边界清楚的肿块，CT呈稍高密度，MRI呈T1WI低信号，T2WI稍高信号，增强扫描一般均匀强化，部分不均匀强化。松果体母细胞瘤肿瘤呈深分叶状，形态不规则，肿瘤内部可见出血、囊变、坏死，增强扫描明显不均匀强化，中间分化的松果体实质细胞瘤影像学表现介于松果体细胞瘤及松果体母细胞瘤之间。脑膜瘤呈圆形或类圆形，形态规则，边界清楚，与周围组织分界清楚，CT呈稍高密度，T1WI呈等信号，T2WI呈等稍低信号，信号/密度均匀，增强扫描明显均匀强化，并可见“脑膜尾征”。结论：松果体区域组织成分较复杂，肿瘤种类较多，影像学表现多种多样；需结合影像学表现（肿瘤形态、边界、其与周围组织关系、强化特点）及临床资料（患者年龄、性别、实验室检查等）综合考虑做出诊断。     

颅内孤立性纤维瘤的影像表现

目的 探讨颅内孤立性纤维瘤(ISFT)的影像特征.方法 回顾性分析经病理及免疫组织化学证实的10例ISFT患者的CT及MRI表现.所有患者均行MR平扫及增强扫描,其中4例行CT平扫.结果 所有病例术前均误诊为脑膜瘤,5例位于幕上、4例位于幕下、1例同时生长于幕上及幕下.所有病变均起源于颅内硬脑膜,8例肿瘤边缘可见明显分叶或浅分叶.4例CT检查均呈稍高密度,1例压迫颅底骨质致骨质吸收.仅1例可见包膜点样钙化,所有病灶实质内均未见钙化.T1WI以等、稍高信号为主,4例病灶信号均匀、6例信号不均.T2WI 2例病灶呈均匀等信号及低信号,4例表现为等、稍高或低信号相间,2例合并囊变,2例可见稍高T2信号及低T2信号两部分,呈所谓“阴阳征”.增强扫描所有病灶均明显强化,8例强化不均匀,低T2信号区域可见明显强化,4例出现“脑膜尾征”.结论 ISFT影像表现具有一定特点,当脑外肿瘤明显分叶,T2WI信号不均,存在低T2信号区域并明显强化,“脑膜尾征”较少或轻,无颅骨增厚等征象时有助诊断,典型“阴阳征”提示孤立性纤维瘤可能性大.     

颅内软骨瘤的CT、MRI诊断

目的总结探讨颅内软骨瘤的CT、MRI特点。方法对1994年1月至2004年9月经手术病理证实的10例颅内软骨瘤的CT、MRI特点进行回顾性分析。结果10例中，肿瘤位于颅底4例，大脑凸面4例，大脑镰区、脑实质内各1例；CT上均见到明显的钙化且边缘清楚，密度多不均匀（9例），相邻骨质可受累（5例）；于MRI上呈混杂信号（4例），其中钙化部分呈长T1、短T2信号，实质部分呈等长T1、长T2信号；CT增强扫描出现轻度强化4例，其中3例为延迟强化。结论颅内软骨瘤好发于颅底、大脑凸面及大脑镰区，多数伴有明显钙化，增强扫描呈轻度强化，延迟强化较有特点。病理仍是主要的确诊手段。     

Configurational MR characteristics of metastatic brain tumors

Magnetic resonance (MR) characteristics of metastatic brain tumors (MBTs) were studied using 15 cases (13 males and 2 females whose ages ranged from 32–78 yr, with the mean age of 57.8 yr;12 adenocarcinomas, 2 squamous-cell carcinomas, 2 large-cell carcinomas). Nine cases showed hypointensities and five showed isointensities on T1-weighted images. Six cases showed markedly hypo- or hypointensities, two showed isointensities, and six showed markedly hyper- or hyperintensities on T2-weighted images. One case was markedly hyperintense on both T1- and T2-weighted images. The decrease of the signal intensity on the T2-weighted image was the main MR characteristic. A hypointense peritumoral rim was seen in four of the six hyperintense tumors on T2-weighted images. There was no correlation between the signal intensity and the histological classification.     

MR扩散加权成像对颅内囊性肿块的鉴别诊断价值

目的 :探讨MR扩散加权成像对颅内囊性肿块的鉴别诊断价值。方法 :搜集有手术病理结果的患者 3 1例 ,其中表皮样囊肿 9例 ,蛛网膜囊肿 15例 ,囊性颅咽管瘤 4例 ,颅底囊性变神经鞘瘤 3例。所有病例均行MR常规T1WI、T2 WI及DWI扫描 ,回顾性分析各组病例的MR常规及扩散加权成像表现。结果 :在MR扩散加权图像上 ,所有 7例表皮样囊肿均为显著高信号 ,而在指数扩散加权像及ADC图上为等信号 ;其余病变在扩散加权图像上为低信号或伴等信号。结论 :MR扩散加权成像有助于表皮样囊肿与其它颅内脑外囊性肿块的鉴别 ,表皮样囊肿的扩散加权高信号主要是由“T2余辉效应”而非水分子扩散受限所致。     

MRI and pathological findings in two cases of askin tumors

Summary Askin tumors are primitive peripheral neuroectodermal tumors (PPNET) located in the thoracopulmonary region. This entity was first proposed in 1979 by Askin et al. These highly malignant tumors occur primarily in children and young adults. Pre- und postoperative MRI findings are presented for two pathologically proven cases. MRI is the most appropriate imaging modality for the diagnosis and eventual follow-up for these tumors. They appear homogenous, and iso- or discretely hypointense in comparison to the spinal cord on T1-weighted images and hyperintense on proton density and T2-weighted images. They show a very stark contrast enhancement after i. v. injection of paramagnetic contrast agents. Sharp tissue borders, and exact tumor extension were shown in both cases. The high signal intensity on T2-weighted images was not altered by chemotherapy.     

Supratentorial Gangliocytoma Mimicking Extra-axial Tumor: A Report of Two Cases

We report two cases of supratentorial gangliocytomas mimicking an extra-axial tumor. MR imaging indicated that the tumors were extra-axial, and meningiomas were thus initially diagnosed. Relative to gray matter, the tumors were hypointense on T1-weighted images and hyperintense on T2-weighted images. On contrast-enhanced T1-weighted images, homogeneous enhancement was observed, while CT scanning revealed calcification in one of the two cases.     

肝细胞癌的低场MR征象分析(附33例报告)

目的分析肝细胞癌在低场MR的征象.方法收集33例手术病理证实的肝细胞癌的术前低场MR资料进行分析.结果1.肿瘤实质信号均匀区的信号配对主要分为三类1T1WI稍低、T2WI稍高信号18例;2T1WI等、T2WI稍高信号13例;3T1WI稍高、T2WI稍高信号2例.2.肿瘤实质内MR异常信号区1T1WI低、T2WI高信号(斑点状24例,片状9例,条状5例);2T1WI稍低、T2WI高信号(斑点状8例,片状2例,条状3例);3T1WI高、T2WI高信号(斑点状4例,片状2例);④T1WI低、T2WI低信号(斑点状5例,片状6例,条状2例).3.肿瘤边缘在T2WI上分三种1边缘清楚无分叶21例,其中11例可以见到"包膜征”;2边缘清楚伴分叶5例;3边缘不清7例.结论1低场MR中,肝细胞癌的肿瘤实质在T1WI可以是多种信号,缺乏特征性,但在T2WI均为稍高信号.2MR诊断肝细胞癌一定要有瘤内异常信号.3肝细胞癌的MR边缘部的形态应以T2WI为准,肿瘤边缘可以光滑清楚,也可以分叶状或边缘不清,"包膜征”有诊断意义.     

Hepatocellular carcinoma: correlation of MR imaging and histopathologic findings.

Seventy-two histologically proved nodular hepatocellular carcinomas (HCCs) were studied with magnetic resonance (MR) imaging at 1.5 T. Capsules were present in 56 of the 72 tumors. Thirty-seven capsules were depicted on T1-weighted spin-echo MR images, and 16 were depicted on T2-weighted MR images. Visualization was dependent on thickness and structure of the capsules. Of the 72 tumors, 36 had a mosaic pattern. A mosaic pattern was visualized in 12 of the 36 tumors on T1-weighted images and in 27 of the 36 tumors on T2-weighted images. Six tumors were determined to be histologic grade 1, and all were hyperintense on T1-weighted images, regardless of whether intracellular fat deposits were present. Four of the six grade 1 tumors were isointense on T2-weighted images. In contrast, grades 2 and 3 tumors had various signal intensities on T1-weighted images and most were hyperintense on T2-weighted images. Twenty-one of 32 tumors (66%) with focal areas of increased signal intensity on T2-weighted images had intratumoral dilated sinusoids at histologic examination.     

MR imaging of intradural extramedullary tumors.

Thirty-one consecutive intradural extramedullary spinal tumors examined with MR at 0.3 T were reviewed. In 13 of the patients myelography had been performed. There were 11 patients with meningeoma, 14 with neuroma, one ependymoma, 3 metastases, and 2 lipomas. All tumors were surgically removed and verified by histology. The intradural extramedullary location of the tumors was accurately assessed by MR imaging in all patients and by myelography in 10 of 13. The MR diagnoses were in accordance with the histologic findings in 74% of cases. Compression of the spinal cord or cauda equina with widening of the subarachnoid space above and below the mass or outward displacement of epidural fat was characteristic of the intradural extramedullary tumors. The signal intensity of meningeoma as well as of neuroma was slightly lower or equal to that of the cord on T1-weighted images, and equal to or higher than cord signal on T2-weighted images. Neuroma had a lower signal intensity on T1-weighted images and a higher signal intensity on T2-weighted images than meningeoma. Meningeoma appeared more homogeneous than neuroma and had a broad base towards the dura.     

脊髓室管膜下瘤的MR影像诊断

目的 研究脊髓内室管膜下瘤的MRI特征。方法 4例脊髓室管膜下瘤均行MR检查并经手术病理证实，均为男性，年龄15—47岁，平均36．3岁。回顾性分析脊髓内室管膜下瘤的MRI表现，结合术中所见总结MRI诊断与鉴别诊断要点。结果 4例脊髓内室管膜下瘤分别位于C3～T3、C2～6、T6～12、C1—T2段脊髓，肿瘤均位于脊髓腹侧，呈偏中心性生长。1例有轻度脊髓空洞。MR T1WI为等或低信号，信号不均，内有更低信号；T2WI为高信号。2例伴有小出血灶。增强扫描，3例肿瘤无强化或强化轻微，1例强化明显。结论 MRI可以很好评价脊髓内室管膜下瘤，当患者具备上述特点时高度提示脊髓内室管膜下瘤的可能。