非小脑蚓部髓母细胞瘤的MRI分析

目的 提高对非典型部位髓母细胞瘤的认识.资料与方法 回顾性分析11例经手术病理证实的位于非小脑蚓部髓母细胞瘤的MRI表现.结果 11例髓母细胞瘤中,9例位于小脑半球(左侧4例,右侧5例),1例位于左侧桥小脑角区,1例位于左侧桥臂.7例肿瘤内见囊变坏死区.MRI信号特征和典型部位的髓母细胞瘤相似,T1WI呈低或稍低信号,T2WI呈高或稍高信号,增强后呈不同程度强化.11例均引起第四脑室不同程度受压、移位;6例出现不同程度脑积水;8例瘤周出现轻重不等的水肿.结论 非小脑蚓部髓母细胞瘤多位于小脑半球.仔细分析其MRI特征有助于术前正确诊断.     

MRI在脑干血管母细胞瘤的诊断价值

目的:分析脑干血管母细胞瘤的MRI表现特点,讨论MRI诊断价值及鉴别诊断。材料和方法:经手术和病理证实7例,其中男性2例,女性5例,年龄19~45岁,平均28.7岁;均经MRI平扫及增强扫描。结果:7例脑干血管母细胞瘤1例位于延髓,2例位于延髓与脑桥交界处,4例位于脑桥。6例为单发囊性,呈大囊小结节,囊液呈长T1长T2信号,瘤结节呈不规则形,T1WI为稍低或等信号强度,T2WI呈较高信号强度。瘤旁无水肿或水肿较轻。增强扫描瘤结节明显强化,部分囊壁呈环形强化。1例为实质性,T1WI呈中等偏低信号,T2WI呈中等偏高信号,增强扫描肿瘤显著增强。肿瘤实质内及肿瘤旁可见迂曲的血管流空影。结论:MRI对脑干血管母细胞瘤的诊断具有较高的准确性,尤其是增强扫描对定性诊断及鉴别诊断具有重要价值。     

脊髓血管母细胞瘤的MRI诊断与鉴别诊断

目的探讨脊髓血管母细胞瘤的MRI表现特征。方法回顾性分析8例经手术和病理证实的脊髓血管母细胞瘤的临床及MRI检查资料。结果6例单发,2例多发,所有病灶均位于脊髓内,颈髓及胸髓各5个,肿瘤多呈点状或结节状、香肠状、葫芦形或不规则形,壁结节MRT1WI呈等信号,T2WI呈稍高信号,增强后肿瘤呈显著强化,肿瘤常继发囊肿或大范围脊髓空洞以及水肿,大于lcm的肿瘤内部及周围常见流空血管影。结论脊髓血管母细胞瘤的MRI影像表现具有特征性,掌握这些MRI表现有利于提高脊髓血管母细胞瘤的诊断正确性。     

儿童幕下髓母细胞瘤的MRI诊断

目的 :分析儿童幕下髓母细胞瘤MRI常规及DWI表现,掌握髓母细胞瘤常见影像学特征,并了解其不常见影像学特征。方法:回顾性分析23例经病理确诊为幕下髓母细胞瘤的MRI资料,扫描图像包括T1WI、T2WI、DWI及增强扫描。由2名放射科医师采用单盲法分析MRI图像。结果:23例中,常见表现为肿块位于小脑蚓部18例,实性为主、散在小囊变15例;16例T1WI呈等、低信号,T2WI呈高、稍高信号,DWI呈高信号,ADC值为(0.68±0.16)×10-3mm2/s,增强扫描病灶中度或明显强化16例。不常见表现为肿瘤位于小脑半球(2例),第四脑室(2例),桥小脑角(1例),大囊变(1例在小脑半球,2例在蚓部),T1WI呈低信号,T2WI呈高信号,DWI呈稍高信号(7例),ADC值为(0.73±0.18)×10-3mm2/s,轻度强化5例,结节样强化1例,环形强化1例。结论:发生于小脑蚓部、实性为主、小囊变、DWI高信号是儿童幕下髓母细胞瘤的MRI常见表现,诊断不难。髓母细胞瘤不常见表现多样,结合病灶DWI信号特点,可与幕下其他肿瘤相鉴别,提高诊断水平。     

不典型髓母细胞瘤MR表现及鉴别诊断

目的 探讨不典型髓母细胞瘤的MR表现特点.方法 收集经手术证实的髓母细胞瘤21例,其中男18例,女3例,年龄10～37岁.所有病例均行MRI平扫与增强扫描,并对其临床MRI表现进行回顾性分析.结果 肿瘤位于小脑蚓部6例,小脑半球6例,小脑蚓部及小脑半球4例,第四脑室内5例.肿瘤内发生囊变18例,囊变区内壁光滑.MRI扫描T1WI呈稍低信号,T2WI呈与小脑半球一致的等信号,肿瘤周围见不同程度的水肿.增强扫描呈中等程度或明显强化,部分小脑半球呈磨玻璃状强化.结论 MRI能够针对典型及不典型髓母细胞瘤作出明确的定位与定性诊断.     

常规MRI联合DWI和~1H-MRS诊断成人髓母细胞瘤的价值

目的探讨MRI常规扫描结合DWI及~1H-MRS对成人髓母细胞瘤的诊断价值。方法回顾性分析经手术病理证实的成人髓母细胞瘤14例,均行常规MRI扫描,2例行DWI检查,4例行MRS检查。结果小脑半球5例(35.7%),小脑蚓部3例(21.4%),第四脑室2例(14.3%),桥小脑角区2例(14.3%),右侧小脑半球、小脑蚓部及右侧桥小脑角2例(14.3%)。2例误诊,诊断准确率约85.7%。13例(92.9%)肿瘤内或边缘见大小不等囊变或坏死区。4例(28.6%)肿瘤内可见供血血管影。实性部分:T_1WI序列呈低信号9例,呈等信号5例;T2WI序列呈略高信号6例,呈等信号6例,呈低信号2例;FLAIR序列呈稍高信号6例,等信号8例。肿瘤实性部分均明显强化。2例肿瘤实性部分DWI分别呈高或略高信号,ADC图呈低或略低信号。4例MRS均表现为Cho峰明显升高,NAA峰及Cr峰明显降低;Cho/Cr比值增大,NAA/Cr比值降低。结论 MRI常规扫描结合DWI及~1H-MRS对成人髓母细胞瘤的诊断和鉴别诊断具有重要价值。     

小脑髓母细胞瘤的MRI表现

目的：探讨小脑半球髓母细胞瘤的MRI表现,提高对髓母细胞瘤的认识。方法：8例经手术病理证实的小脑半球髓母细胞瘤患者,男5例,女3例,年龄1～33岁,所有病例均行MRI平扫及增强扫描,其中2例行CT平扫,回顾性分析其临床及影像学表现。结果：肿瘤位于小脑半球深部4例,小脑半球表面且突向桥小脑角区2例,双侧小脑半球及小脑蚓部多发病灶2例。肿瘤内发生囊变5例,囊变区大小不一,3例位于肿瘤周边,2例位于中央,其内壁光滑。MRI平扫肿瘤实性部分T1W1呈稍低信号,T2WI呈等信号或稍高信号,且信号不均匀,5例肿瘤周围有轻度水肿。增强扫描3例肿瘤有轻度强化,5例中度强化,其中1例有脑回状强化。2例CT平扫示肿瘤呈稍高密度。结论小脑半球髓母细胞瘤的MRI表现具有一定特征性,MRI检查对诊断本病有重要价值。     

成人髓母细胞瘤MRI诊断及误诊分析

目的探讨成人髓母细胞瘤MRI表现并分析误诊原因。方法回顾性分析15例经手术和病理证实的成人髓母细胞瘤的术前MRI表现,15例均行头颅常规MR扫描及T1WI增强扫描,3例加做DWI。结果 5例位于后颅窝中线(小脑蚓部3例,四脑室区2例),8例位于小脑半球(左侧3例,右侧5例),2例位于左侧桥小脑角区。T1WI病灶呈稍低至等信号,T2WI及FLAIR为稍高至等信号,内可见囊变区,肿瘤实质ADC图为低信号,强化形式多样。术前正确诊断为髓母细胞瘤4例,误诊为室管膜瘤3例,血管母细胞瘤、脑膜瘤和神经鞘瘤各2例,胶质母细胞瘤、淋巴瘤各1例。结论成人髓母细胞瘤少见,发病部位多变和MRI表现缺乏特异性,是误诊的主要原因。     

幕下多发实质型血管母细胞瘤MRI诊断

目的探讨幕下多发实质型血管母细胞瘤MRI特征,提高对幕下实质型血管母细胞瘤的诊断水平。方法回顾性分析6例经手术和病理证实的幕下多发实质型血管母细胞瘤的MRI表现及相关临床资料,全部病例均行MRI平扫及增强。结果 6例患者全部多发,共25个病灶,位于右侧小脑半球者10个,左侧7个,位于延髓背侧2个,桥小脑角1个,紧贴小脑幕4个,小脑蚓部1个。MRI T1WI呈等或稍低信号,T2WI呈高或稍高信号,FLAIR序列呈等或稍高信号,SWI序列1个病灶周边见低信号含铁血黄素环。瘤内及周边可见迂曲血管,较大肿块瘤内及周边可见多发血管流空信号,增强扫描肿瘤呈均匀明显强化。10个病灶与邻近脑膜关系密切。结论幕下多发实质型血管母细胞瘤MRI表现具有一定特征性。     

成人小脑髓母细胞瘤的MRI表现

目的:探讨成人小脑髓母细胞瘤的MRI表现及其诊断价值。方法:回顾性分析12例(男5例,女7例,年龄26~49岁,中位年龄28岁)经手术病理证实的成人小脑髓母细胞瘤MRI资料,所有病例均行1.5T MRI平扫及增强扫描。结果:右侧小脑半球4例(其中1例为多发病灶),左侧小脑半球6例,小脑蚓部2例。肿瘤T1WI呈稍低信号,T2WI及FLAIR呈等或稍高于小脑灰质信号,DWI呈稍高信号;肿瘤内部可见裂隙状或斑片状T1WI低、T2WI高信号;肿瘤周围可见片状或环状水肿。增强扫描10例呈渐进性轻中度强化,2例明显强化。均未见蛛网膜下腔种植转移。结论:成人小脑髓母细胞瘤以小脑半球多见,可多发,易囊变,增强扫描呈渐进性轻中度强化,较少出现蛛网膜下腔种植转移,MRI表现具有一定的特征性。     

脊髓血管母细胞瘤的MRI表现

目的评估脊髓血管母细胞瘤的MRI表现。资料与方法回顾性分析7例经手术病理证实的脊髓血管母细胞瘤的MR／表现。7例均行常规MR扫描,应用T1、T2加权序列作轴面、矢状面扫描,且均应用T1WISE作轴面、矢状面、冠状面增强扫描。结果7例肿瘤在T1WI上呈等信号、低信号或等、低混杂信号,在T2WI上呈高信号或混杂信号,增强后均一或不均一强化。其中5例伴有脊髓空洞,4例可见血管流空效应,2例伴有瘤周水肿。结论脊髓血管母细胞瘤的MRI表现具有特征性。MRI还有利于明确肿瘤的位置和范围,以及外科治疗计划的制定。     

脊髓星形细胞瘤的MRI表现

目的:探讨脊髓星形细胞瘤在MRI中的影像表现,提高对该疾病的认识。方法:回顾分析12例经手术和病理证实的脊髓星形细胞瘤的磁共振影像表现。结果:5例病灶位于颈髓内,6例位于胸髓内,1例位于脊髓圆锥内;4例位于脊髓中央,8例位于脊髓周边部位。病灶平均长径为5.3 cm。平扫T1WI检查中4例表现为稍低信号,3例表现为等信号,5例表现为等、低混杂信号;T2WI检查中,10例表现为高信号,2例表现为高低混杂信号。增强扫描病灶实体部分10例出现强化。8例病灶边界显示不清晰,4例显示清晰。6例见囊变。结论:磁共振成像对髓内星形细胞瘤的定位和定性具有重要的价值。     

软骨肉瘤的影像诊断与鉴别诊断

目的:探讨软骨肉瘤的影像学表现,提高对本病诊断的准确性。方法:回顾性分析25例经手术病理证实的软骨肉瘤的X线、CT和MRI资料。结果:25例软骨肉瘤中原发23例,其中普通型20例,去分化型、黏液型及透明细胞型各1例;继发2例。X线及CT表现:原发的23例中溶骨性骨破坏5例,混合性骨破坏18例,形成软组织肿块20例,其中表现为低密度19例,等密度1例。20例普通型及1例黏液型见散在钙化。MRI表现:普通型软骨肉瘤T1WI呈等或稍低信号,T2WI呈等或稍高信号;黏液型T1WI呈等、低混杂信号,T2WI呈稍高、低的混杂信号,钙化T2WI呈低信号;透明细胞型病例T1WI及T2WI呈近乎等信号;去分化型T1WI呈等低混杂信号,T2WI呈不均匀高信号。6例普通型及1例继发型出现环形、间隔样中等-明显强化,黏液型及去分化型呈不均匀中等-明显强化。结论:普通X线及CT是软骨肉瘤影像诊断及鉴别诊断的主要手段,MRI显示软骨信号为重要提示。MRI显示病变范围更为清楚、准确,为临床治疗提供可靠依据。     

肺癌脊髓内转移的MRI诊断

目的：探讨肺癌脊髓内转移（ISCM）的MRI表现特征及病理机制。方法：对3例经手术病理证实及4例临床确诊的肺癌脊髓内转移的MRI表现进行回顾性分析。全部病例均行MRI平扫及钆喷替酸葡甲胺（Gd-DTPA）增强扫描。结果：7例转移瘤均为单发，3例位于胸段，4例位于脊髓圆锥部。主要MRI表现：肿瘤均位于脊髓中央，T1WI1例呈低信号，6例呈等信号，T2WI全部为高信号，病灶上下方髓内可见水肿2例，空洞3例；平扫肿瘤边界模糊不清，增强扫描均呈明显强化，其中3例呈不均匀强化，3例呈环形强化，1例呈结节样强化，增强后肿瘤边界显示十分清楚。结论：肺癌脊骨转移的MRI表现常为明显强化的髓内肿物，但其缺乏特征性，定性诊断需结合临床资料综合分析。     

脊柱转移瘤的MR诊断

目的 探讨脊柱转移瘤的MR诊断。方法 回顾性分析120例脊柱转移瘤的MR表现。结果 脊柱转移瘤灶的异常MR表现为：（1）信号异常,在T1WI上,112例（93.3%)呈低信号,8例（6.7%)为等或混杂的信号,在T2WI上,89例（74.1%)呈稍高信号,33例（27.5%)为低或混杂信号;（2）病灶可呈跳跃式破坏,椎体附件受累,出现椎旁软组织肿块,但椎间隙保持完整;（3）伴发椎体压缩性骨折的病灶可呈“楔形”、“盘状”或“倒楔形”。脂肪抑制增强扫描可显示病变范围并发现平扫中未能发现的病变。结论 MRI是诊断脊柱转移瘤的可靠而重要的手段。     

低磁场MRI诊断脊髓内肿瘤的价值

目的: 探讨低磁场MRI诊断脊髓内肿瘤的价值和误诊原因.材料和方法: 对34 例手术和病理证实的髓内肿瘤进行回顾性分析.结果: 室管膜瘤20例, 星形细胞瘤11例, 脂肪瘤2例,血管母细胞瘤1 例,32例肿瘤MRI表现为T1WI等或低信号,T2WI高信号,2例脂肪瘤T1WI和T2WI均为脂肪信号.注射Gd-DTPA后室管膜瘤实性部分呈均匀明显增强 "腊肠样"(12例),星形细胞瘤散在斑片状增强(6例),误诊3例,包括2例多发性硬化、1例急性脊髓炎.结论: 低磁场MRI可为脊髓内肿瘤的早期诊断提供较准确的影像学依据.     

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。     

Magnetic resonance imaging spectrum of spinal meningioma

PurposeTo evaluate magnetic resonance (MR) imaging findings of spinal meningioma and to determine the radiological subtypes based on the MR imaging findings and their respective clinical features.Material and methodsData for 105 patients with surgically treated and histopathologically diagnosed spinal meningiomas at our hospital between May 1, 2003 and May 1, 2017 were evaluated in this study. Two radiologists reviewed the characteristics of spinal meningiomas on MR images and categorized the spinal meningiomas into subtypes based on MR imaging findings.ResultsMost spinal meningiomas showed higher signal intensity than that of the spinal cord but lower than that of the subcutaneous fat on T2-weighted images (WI). 56 cases (54%) showed adjacent spinal cord signal changes. Meningiomas could be categorized according to MR imaging findings into type A: dural-based tumors with a homogeneous signal intensity and intense contrast enhancement (81 cases, 77%); type B: round or oval-shaped tumors with an internal hypointense portion on T2-weighted images (18 cases, 17%); type C: en plaque tumors (three cases, 3%); and type D: tumors with unusual findings and a heterogeneous appearance (three cases, 3%). All type C patients showed spinal cord signal changes.ConclusionsSpinal meningioma showed slightly high signal intensity rather than high signal intensity on T2-weighted images. Spinal cord signal changes were present in more than half of the cases. Clinical differences were observed among the different MR imaging types.     

MR findings in spinal hemangioblastoma: correlation with symptoms and with angiographic and surgical findings

BACKGROUND AND PURPOSE: To our knowledge, a detailed analysis of MR findings in spinal hemangioblastoma has not been conducted to date. Our purpose was to elucidate the MR features of this disease with special attention to tumor size, correlation with MR findings and clinical symptoms, and any differences between patients with and without von Hippel-Lindau disease (VHLD). METHODS: MR images in five patients with VHLD and seven patients without VHLD were reviewed retrospectively for spinal hemangioblastoma by two neuroradiologists. The MR findings were correlated with clinical symptoms and with angiographic and surgical findings. RESULTS: The MR features depended on the size of the spinal hemangioblastoma. Small (10 mm or less) hemangioblastomas were mostly isointense on T1-weighted images, hyperintense on T2-weighted images, and showed homogeneous enhancement. Larger hemangioblastomas tended to be hypointense or mixed hypo- and isointense on T1-weighted images, heterogeneous on T2-weighted images, and tended to show heterogeneous enhancement. Small hemangioblastomas were located at the surface of the spinal cord, most frequently along its posterior aspect. These were subpial in location at surgery and showed well-demarcated, intense enhancement. Symptomatic small hemangioblastomas had relatively large associated syringes, whereas asymptomatic ones did not. A hemangioblastoma larger than 24 mm was invariably accompanied by vascular flow voids. There was no difference in the MR findings between the two patient groups except for the multiplicity and higher percentage of small tumors in patients with VHLD. CONCLUSION: Knowledge of these MR features helps to differentiate spinal hemangioblastoma from other diseases that show enhancing nodules.     

Spinal cord tumors: gadolinium-DTPA-enhanced MR imaging

Summary To assess the utility of gadolinium-DTPA (Gd) and of MR imaging in the evaluation of spinal cord tumors, ten consecutive patients were prospectively evaluated. T1-proton density-, and T2-weighted images were obtained in sagittal or axial planes. T1-weighted images were obtained before and after intravenous administration. Five tumors were within the cervical spinal cord; 3 neoplasms were within the thoracic cord; 1 neoplasm extended from the cervical to the thoracic cord and 1 neoplasm extended from the cervical cord to the conus medullaris. Four tumors were ependymomas; 3 were astrocytomas; 1 was an hemangioblastoma, and 1 was a metastatic malignant peripheral nerve sheath tumor. The remaining patient died prior to spinal surgery and no autopsy was obtained. Of theprecontrast sequences, tumors were best evaluated using T1-weighted images. Abnormal findings included cord widening, presence of a tumor mass, intratumoral or other associated cyst(s), and hemorrhage. Nevertheless, T1-weighted images obtainedfollowing the administration of GD were superior relative to all other pre- and post-contrast sequences for defining tumor margins, characterizing cyst(s) and delineating tumor masses. Based primarily on their appearance on post-contrast T1-weighted images, tumor-associated cysts could be subcategorized into 3 types: intratumoral cysts (foundwithin the contrast-enhancing soft tissue mass); nonenhancing extratumoral cysts (found either rostral or caudal to the enhancing tumor mass); and enhancing extratumoral cysts (having an enhancing wall or containing an enhancing nodule). Our results indicate that T1-weighted MR images obtained both before and after administration of Gd are sufficient for characterizing the varying components of intramedullary spinal cord tumors. This information assists in treatment planning and follow-up of patients with these tumors.Presented in abstract form at meetings of the American Academy of Neurology, Chicago, Illinois, April, 1989