CT所见咽周间隙的改变在判断鼻咽癌侵犯定位中的意义

目的 为在CT上更准确判断鼻咽癌(NPC)的侵犯部位。资料与方法搜集初诊NPC30例，同时进行鼻咽部CT和MRI扫描，将其咽周间隙的影像学表现对照观察。结果 鼻咽缝间隙对称存在14例，1例椎前肌受累，占7．14％；不对称性变窄或消失者16例，椎前肌受累14例，占87．5％。CT上咽旁间隙变窄伴线样低密度影或密度增高20例，MRI上其间隙内的高信号脂肪影受压或间隙极度变窄，但仍连续无中断；CT上咽旁间隙消失5例，MRI上翼内肌均受累。结论 鼻咽缝间隙不对称性变窄或消失高度提示椎前肌受累；咽旁间隙变窄伴线样低密度影或密度增高时，肿瘤未跨越咽旁间隙；当咽旁间隙消失时，肿瘤多已突破咽旁间隙累及颞下窝。     

左侧胸壁胸小肌下冬眠瘤影像表现一例

本文报道左侧胸壁胸小肌下冬眠瘤一例。患者,男,61岁。CT表现为左侧胸壁胸小肌下椭圆形低密度为主的软组织肿块,与皮下脂肪接近但不完全相同,CT值约-50HU,内部可见线样、曲线样分隔。MRI平扫表现为轴面T2WI见左侧胸壁胸小肌下水滴状高信号,略低于皮下脂肪信号,其内可见网状线状低信号,轴面T2WI脂肪抑制见该病灶信号明显减低,其内可见网状线状高信号,冠状面T2WI见该病灶信号呈半球状,轴面T1WI脂肪抑制可见该病灶信号低于皮下脂肪信号,其内可见网状线状低信号,DWI未见信号增高。病理诊断:(左侧胸壁肿物)冬眠瘤。     

儿童眼眶转移性神经母细胞瘤和绿色瘤的特征性MR表现

目的 分析儿童眼眶转移性神经母细胞瘤和绿色瘤的特征性MR表现。资料与方法 回顾性分析经手术病理证实的9例儿童眼眶转移性神经母细胞瘤和5例绿色瘤的CT和MRI表现。所有病例均行CT平扫以及MRI平扫和增强扫描。结果 14例CT表现均为眼眶不规则肿块和邻近的眶壁溶骨性骨质破坏,7例骨质破坏区邻近的颅内可见扁平不规则肿块。2例转移性神经母细胞瘤表现为眼眶肌锥外间隙肿块内有与眶外壁垂直的针状高密度影。14例MRI表现为眼眶肌锥外间隙略长T1、略长T2信号不规则软组织影,7例骨质破坏区邻近的颅内硬膜外间隙可见略长T1、略长T2信号扁平不规则肿块,增强后明显强化。14例双侧眶骨及蝶骨大翼,9例斜坡和双侧岩尖及2例双侧颞骨鳞部骨髓腔脂肪高信号影被略长T1、略长T2信号影取代,采用脂肪抑制的增强T1WI显示均有强化,强化程度与眼眶内肿块相似。结论 儿童眼眶转移性神经母细胞瘤和绿色瘤的眶壁和颅面骨MR表现具有特征,有助于诊断和鉴别诊断。     

结节性筋膜炎MRI表现与病理对照分析(附1例报告并文献复习)

目的:提高对结节性筋膜炎MRI表现的认识。方法:分析1例经术后病理确诊的结节性筋膜炎,结合文献,探讨其MRI表现与病理学的相关性。结果:本例发生于小腿上段肌间筋膜。X线发现胫骨旁长椭圆形高密度影。MRI显示病变为长T1长T2信号为主的肿块影,周边可见纤细的包膜样结构,肿块内可见条状、分隔状及小片状的等T1等T2信号。病理分型为混合型结节性筋膜炎。结论:结节性筋膜炎MRI表现与病理有一定的相关性,本病虽为一种良性病变,但应与纤维肉瘤、恶性纤维组织细胞瘤、黏液型脂肪肉瘤等疾病相鉴别。     

CT和MRI对鼻腔和鼻窦腺样囊性癌的诊断价值

目的 探讨CT和MRI在鼻腔和鼻窦腺样囊性癌(adenoid cystic carcinoma, ACC)中的应用价值. 方法 回顾性分析13例经手术病理证实的鼻腔和鼻窦ACC的临床及影像学资料.结果 肿块发生于鼻腔5例,其中左侧4例、右侧1例、双侧1例,筛窦4例,其中左侧2例、右侧1例、双侧1例,上颌窦3例,均为左侧.CT表现:所有病变均呈形态不规则的软组织肿块影,其中7例呈等、低混杂密度,4例呈等密度影,2例为等、低混杂密度影中夹杂斑片状高密度影.病变均呈膨胀性生长,与周围组织分界不清楚,邻近骨质均可见不同程度的骨质破坏.5例累及翼腭窝,表现为翼腭窝扩大,其内脂肪间隙变窄,软组织密度影填充.MRI表现:6例行MRI检查病例均呈混杂信号,T1WI呈等、低信号,T2WI呈等、高信号;增强扫描均呈不均匀强化.发生于双侧筛窦的1例见病变邻近脑膜增厚、强化.结论 CT和MRI联合应用,能为制订鼻腔和鼻窦ACC手术方案提供更多信息.     

畸形性骨炎的影像学诊断

目的 探讨畸形性骨炎的影像学特征.方法 回顾性分析22例经病理证实的畸形性骨炎患者资料,20例行X线检查,13例行CT检查,17例行MRI检查,三者均进行10例.分析X线、CT及MRI表现,总结其影像学特征.结果 22例中,海绵型6例,硬化型4例,混合型12例.15例多骨发病,7例单骨发病.X线及CT表现:海绵型以骨质破坏为主,骨皮质膨胀、破坏,呈"丝瓜瓤"样改变,骨髓腔变窄或闭塞消失;硬化型以骨质修复、硬化为主,骨质密度增高,骨皮质增厚,骨小梁粗大,骨髓腔变窄或闭塞;混合型表现为骨破坏与骨质修复混合存在,骨小梁粗大而紊乱,骨质破坏区可见"磨玻璃样"或"大理石"样骨硬化.MRI表现:17例患骨体积增大,骨皮质膨胀、破坏,骨质破坏区呈中等T1、中等T2信号,于脂肪抑制序列PDWI上呈高信号,15例呈"朽木征",13例骨髓腔变窄.22例均未见明显骨膜反应及软组织肿块.结论 畸形性骨炎的影像学表现具有特征性,X线平片是首选的检查方法,CT及MRI是X线平片重要的补充手段.     

新生儿咽旁间隙神经胶质异位一例

报道1例经病理证实的新生儿咽旁间隙神经胶质异位。神经胶质异位是一种少见的先天畸形,多见于鼻部,咽旁间隙罕见。CT表现为左咽旁间隙软组织密度肿块,邻近颅底骨质结构完整。MRI表现为左咽旁间隙卵圆形肿块,T 1WI、T 2WI均呈等信号,与脑组织信号相似,增强呈中度不均匀强化,边缘可见包膜样线形强化...     

咽旁间隙多形性腺瘤与神经鞘瘤的影像鉴别诊断

目的探讨咽旁间隙多形性腺瘤与神经鞘瘤的CT与MRI表现,旨在提高对两者的鉴别诊断水平。资料与方法回顾性分析经临床手术病理证实的13例咽旁间隙多形性腺瘤与8例神经鞘瘤患者的CT与MRI表现,重点观察病变所在位置、与周围组织的关系及占位效应。结果 21例咽旁间隙肿块均边界光滑,包膜完整,可见坏死囊变区,体积多较大(最长径多>4 cm),占位效应明显。其中13例多形性腺瘤均来源于腮腺深叶,突向咽旁间隙生长,同侧咽旁间隙受压变窄,向内移位,呈裂隙状位于肿块的内前方,茎突受压向内后方移位。8例神经鞘瘤,肿块与腮腺深叶分界清楚,可见脂肪间隙。结论生长在咽旁间隙的多形性腺瘤与神经鞘瘤的鉴别诊断较难,鉴别诊断需依靠肿块所在位置、与腮腺的关系及其周围结构如咽旁间隙脂肪和茎突的移位情况进行综合分析。     

鼻咽缝间隙的解剖学基础及其影像学表现和意义

目的 在影像上提出鼻咽缝间隙的概念，介绍其CT和MRI表现及其意义。方法 正常CT组43例，正常MRI组36例，均进行鼻咽轴面平扫，其中加做鼻咽冠状面CT和MR扫描各5例，7例加做鼻咽后壁矢状面MR薄层扫描；2例鼻咽轴位断面标本作对照；鼻咽癌（NPC）组30例，同时进行CT与MR扫描，对鼻咽后软组织结构影像学表现进行详细观察分析。结果 鼻咽缝间隙位于椎前并列的头长肌或颈长肌之间，咽后壁后方，枕骨及颈椎前方，它包括上述肌肉之间的咽缝、咽后间隙、危险间隙、椎前间隙部分和组成这些间隙的筋膜，以及其中的纤维结缔组织、脂肪和淋巴结等结构，在CT上表现为三角形不均匀低密度影，在MRI上，呈三角形不均匀高信号影，其正中有粗细不一的低信号咽缝。正常CT组43例均在椎前肌之间出现1个层面以上的、呈低密度的两侧对称的三角形影，为鼻咽缝间隙；在斜坡和硬腭水平之间均见鼻咽缝间隙者22例，部分层面显示鼻咽缝间隙者14例，鼻咽缝间隙达口咽水平者7例。正常MRI组36例，在轴面像上35例在椎前肌之间可见两侧对称的呈不均匀高信号的三角形鼻咽缝间隙；从斜坡至硬腭水平均见鼻咽缝间隙者13例，部分可见11例，鼻咽缝间隙达口咽水平者11例；矢状面像上，鼻咽缝间隙止于C2椎体上部者4例、下部者3例；冠状面像上，鼻咽缝间隙呈纵行条带状影2例，倒置梯形3例。2具鼻咽断面尸体标本均见鼻咽后壁后方并列的头长肌或颈长肌之间三角形疏松纤维结缔组织。NPC组30例中鼻咽缝间隙对称存在者14例，不对称性变窄1例，消失者15例。结论 鼻咽部椎前并列的头长肌或颈长肌之间的结构在CT和MRI上统称为鼻咽缝间隙是合适的；NPC患者的鼻咽缝间隙消失和不对称性变窄多提示肿瘤侵犯椎前肌，而对称存在时，肿瘤多位于鼻咽顶后壁浅层。     

肌肉内脂肪瘤的CT与MRI诊断

目的 探讨肌肉内脂肪瘤的CT与MRI表现.方法 回顾性分析16例经病理证实的肌肉内脂肪瘤患者资料,13例行MRI检查,4例行CT检查,总结其CT与MRI特征.结果 16例中,肌肉内浸润型9例,肌间浸润型7例.CT扫描肿瘤表现为脂肪性低密度,3例肌间浸润型密度均匀,1例肌肉内浸润型密度不均匀,其间可见条索状肌纤维样稍高密度影.MRI上肿瘤中的脂肪组织均呈短T1、长T2信号,脂肪抑制序列PDWI上呈低信号,8例肌肉内浸润型脂肪瘤信号不均匀,肿瘤组织与肌肉纤维交错生长,其中5例可见"羽毛征",5例肌间浸润型脂肪瘤,2例信号均匀,3例信号不均匀,于高信号脂肪组织中可见低信号线样或网状纤维间隔.结论 肌肉内脂肪瘤的CT与MRI表现具有特征性,MRI应作为首选的影像学检查方法.     

Angiomyolipoma arising in the thigh

A 41-year-old man presented with an asymptomatic mass in the right medial thigh. Magnetic resonance imaging (MRI) revealed a well-demarcated, 10-cm mass in the right adductor muscles. The margins of the mass exhibited high signal intensity and the rest showed low or iso signal intensity on T1-weighted MR images. However, the high signal intensity was decreased on T2-weighted images with fat suppression. The central part of the tumor was of inhomogeneous high signal intensity on T2-weighted images; after Gd-DTPA injection it enhanced inhomogeneously on T1-weighted images with fat suppression. On dynamic computed tomography (CT) in the arterial phase, there were strongly enhancing spotty areas in the tumor. At surgery, a yellow-whitish tumor was resected and a pathological diagnosis of angiomyolipoma (AML) in the thigh was made. Received: 21 June 1999 Revision requested: 28 July 1999 Revision received: 13 December 1999 Accepted: 15 December 1999     

MR studies of extension and spread pattern of nasopharyngeal carcinoma

Seven patients with T2-T4 nasopharyngeal carcinoma were examined by MRI on a 0.5T superconducting system. The obtained MRI images were reviewed focusing on the signal intensity (SI) of tumors, and the extension of tumors into the related spaces from the pharyngeal mucosal space (PMS). Consequently, the SI of tumors demonstrated low on T1 weighted images and high on T2 weighted images. The parapharyngeal space was the first space where the tumors extended from the pharyngeal mucosa. The parapharyngeal space was an intermediate point of extension to the masticator space (MS), the carotid space (CS), the retropharyngeal space (RPS), and the prevertebral space (PVS). The PVS involvement by tumors was not a direct extension from the PMS, because the posterior portion of pharyngobasilar fascia worked as a barrier on MR. Therefore, the longus capitus muscle in the prevertebral space was considered to be involved via the parapharyngeal space (PPS). The masticator space involvement was indicated by slightly high SI of pterygoid muscle on T2 weighted images, and also the effacement of the PPS fat and parapharyngeal venous plexus were considered as a sign of involvement into the masticator space. The retropharyngeal lateral lymph node (Rouviere) metastases were recognized by MR. These metastasized lymph nodes were low on T1 weighted images and high on T2 weighted images.     

MRI与CT在鼻咽癌诊断中的应用价值及分期系统比较

目的 评价MRI与CT检查在鼻咽癌诊断中的应用价值,并对鼻咽癌2008年分期、1992年福州分期及2002年国际抗癌联盟(UICC)分期系统进行比较.方法 分析76例鼻咽癌初诊患者MRI和CT影像资料,依据2008年分期以MRI为标准,评价MRI与CT对鼻咽癌新分期的差异.并以MRI为标准,比较鼻咽癌不同分期系统间的差异.MRI与CT对肿瘤侵犯范围比较采用McNemar法检验.结果 MRI判断鼻咽癌翼内肌(22例)、翼外肌(15例)、颅底(35例)及颅内(11例)侵犯方面与CT(分别为24、11、32、6例)存在差异,但无统计学意义(P＞0.05);MRI在判断咽旁间隙侵犯(50例)、咽后组淋巴结转移(48例)、T1期(18例)、T2期(15例)、N0期(18例)、N1期(33例)上,与CT(分别为61、23、11、22、24、27例)不一致者分别为11例、25例、7例、7例、6例及6例,差异有统计学意义(P＜0.05).CT多显示的11例咽旁间隙侵犯,MRI证实5例为咽旁间隙受压,6例为咽后组淋巴结转移,而MRI较CT共多显示咽后组淋巴结转移25例,以上2点为引起T、N分期差异的主要原因.鼻咽癌2008年分期与1992年分期比较,T分期上升9例,下降1例,N分期上升16例,临床分期上升15例,下降1例;与2002年UICC分期比较,T分期上升7例,N分期上升10例,临床分期上升12例.结论 与鼻咽癌2008分期规定的MR检查比较,CT在显示病变咽旁间隙侵犯及咽后组淋巴结转移方面存在较大差异.相对于1992年分期及2002年UICC分期,鼻咽癌2008分期主要使肿瘤T、N分期上升、临床分期上升.     

咀嚼间隙疾病的MRI和CT诊断

目的：评价ＭＲＩ和ＣＴ对咀嚼间隙病变的诊断价值。材料和方法：回顾性分析４２例咀嚼间隙病变的ＭＲＩ和ＣＴ表现。除５例感染经抗炎治疗好转外，均经手术病理证实。结果：５例蜂窝织炎病变弥漫，累及间隙内脂肪、咀嚼肌和周围间隙及其皮下脂肪，无明确肿块和骨质破坏，ＭＲＩ和ＣＴ均具特征，１例炎性肉芽肿有明确肿块和骨质破坏，术前误诊；５例原发性肿瘤均有明确肿块、间隙内脂肪受压消失、翼内肌受压向后内移位和骨质受压或破坏，除软骨瘤外均缺乏组织学特征；３１例累及咀嚼间隙的继发性肿瘤ＭＲＩ和ＣＴ均能显示其侵入的途径和范围。结论：ＭＲＩ和ＣＴ对显示病变的范围、鉴别感染类型、判断肿瘤位置、性质和来源具有重要价值，可帮助临床制定治疗计划     

Magnetic resonance imaging features of nasopharyngeal carcinoma and nasopharyngeal non-Hodgkin's lymphoma: Are there differences?

Purpose

To describe differences in the primary tumour and distribution of cervical lymphadenopathy for cases of nasopharyngeal carcinoma (NPC) and nasopharyngeal non-Hodgkin's lymphoma (NPNHL) using magnetic resonance (MR) imaging.

Materials and methods

MR images of patients with NPC (n = 272) and NPNHL (n = 118) were independently reviewed by two experienced radiologists.

Results

NPC had a higher incidence of tumour invasion associated with the levator and tensor muscles of the velum palatine, the longus colli and medial pterygoid muscles, the base of the pterygoid process, the clivus, the base and greater wing of the sphenoid bone, the petrous apex, the foramen lacerum, the foramen ovale, the hypoglossal canal, and intracranial infiltration. In contrast, NPNHL had a higher incidence of tumour invasion associated with the hypopharynx, the palatine and lingual tonsils, as well as the ethmoid and maxillary sinuses. NPNHL also had a higher incidence of extensive and irregular bilateral lymphadenopathy, and lymphadenopathy in the parotid.

Conclusions

NPC more often involved an unsymmetrical tumour with a propensity to invade both widely and deeply into muscle tissue, the fat space, the neural foramen, and the skull base bone. In contrast, NPNHL tended to be a symmetrical and diffuse tumour with a propensity to spread laterally through the fat space and along the mucosa to the tonsils of the oropharynx and hypopharynx. These differences facilitate a differentiation of these diseases using MR images, and enhance our understanding of the biological behavior of these malignant tumours of the nasopharynx.     

肝脏局灶性结节增生的螺旋CT和MRI诊断

目的 :分析肝脏局灶性结节增生 (FNH)平扫和动态增强的螺旋CT、MRI表现 ,提高FNH诊断符合率。方法 :对 13例经手术病理证实的FNH影像学表现进行回顾性分析。螺旋CT检查 8例 ,MRI检查 6例 ,其中 1例同时做CT和MRI检查。结果 :8例CT平扫病灶均呈低密度 ,均匀或不均匀。增强动脉期扫描除中心疤痕外 ,所有病灶均有明显均匀强化 ,其中 4例还可见到病灶中心或周边增粗、扭曲的动脉。门脉期和延迟期扫描 4例呈略高密度、4例病灶呈等密度或略低密度 ,4例伴有中心疤痕者均有延迟强化。MRI检查 6例 ,病灶均呈不均匀略长或等T1及T2 信号 ,增强动脉期呈明显强化 ,门脉期及延迟期呈等或略高强化 ,4例MRI平扫显示中央瘢痕者有延迟强化。结论 :平扫和动态增强螺旋CT、MRI能较全面显示FNH的病理特征和血供特点 ,明显地提高与其它富血管恶性肿瘤的鉴别诊断能力     

鼻咽癌颈部淋巴结转移的磁共振成像

本文总结了32例鼻咽癌患者颈部淋巴结转移的磁共振成像(MRI)。结果表明:转移淋巴结在T_1加权像为中等信号强度,介于肌肉与脂肪之间,近似于或稍高于原发灶。区分肿瘤与脂肪组织用T_1加权像最好,而T_2加权像则有利于区分淋巴结与肌肉。MRI 尚能够显示CT 不能显示的咽后外侧淋巴结。MRI 作用在于发现临床上不能触到的深在部位的淋巴结,以及鉴别放疗后颈部纤维化与淋巴结转移。另外,当临床上发现单个或单侧淋巴结转移时,MRI 有助于进一步显示多个或双侧淋巴结转移。     

Unusual changing CT and MR appearance of an epithelial intracranial cyst

Introduction: Epithelial cysts are infrequent intracranial lesions and may content cilia and mucosecretant cells that may be responsible for the protein concentration within the contents and the variable radiological appearance on CT and MRI. Methods and patients: We present a case of an extraaxial epithelial cyst with changing CT and MR characteristics. Results: The appearance of our cyst on CT or MRI changed with size and morphology. When CT studies showed an hypodense cyst, the lesion was large but when an hyperdense mass was present, the lesion was smaller. In the later situation MRI showed hyperintensity on T1-weighted images and hypointensity on T2-weighted images and the protein concentration of the cystic contents was high. Conclusions: We believe that a relatively high protein concentration in our cyst was the major factor for the high attenuation on CT and the hyperintensity or hypointensity on T1- and T2-weighted images, respectively. We believe than these atypical imaging findings were caused by changes in the protein concentration within the cyst.