颅咽管瘤的MRI表现及病理分析

目的：分析颅咽管瘤的MRI及病理表现,探讨MRI对颅咽管瘤的诊断价值。方法：回顾性分析56例术前颅脑MRI平扫及增强扫描并经手术病理证实为颅咽管瘤的病例资料,分析其MRI及相关病理表现。结果：颅咽管瘤发生于鞍上20例,鞍内及鞍上30例,鞍内2例,鞍旁2例,桥前池1例,颞顶叶1例。病变囊性25例,囊实性26例,实性5例。囊性部分多呈长T1、长T2信号,实性部分多表现为等T1、等T2信号;Gd-DTPA增强扫描后,囊性部分的囊壁多呈弧形或环形强化,实性部分不均匀明显强化。17例有详细的病理资料,其中成釉质细胞型颅咽管瘤13例,鳞状乳头型颅咽管瘤2例,混合型颅咽管瘤2例。结论：颅咽管瘤的MRI表现具有一定的特点,其信号特征多样性与其病理成分具有一定的相关性,MRI具有很高的诊断和鉴别诊断价值。     

多中心性颅咽管瘤的MRI表现(附4例报告)

目的　分析多中心性颅咽管瘤的MRI表现 ,提高对本病的认识。方法　 4例经手术及病理证实的多中心性颅咽管瘤 ,术前行MRI平扫及Gd -DTPA增强后MRI成像 ,其中 2例行PDWI成像。结果　多中心性颅咽管瘤的MRI表现为鞍区或鞍上区以实性为主的囊实性中心病灶 ,同时在双颞叶、前颅窝底、三脑室前部、桥前池内或尾状核可见多个大小不一的囊性病灶。囊实性病灶在T1WI及T2 WI上分别为低等及高低混杂信号 ;囊性病灶平扫T1WI表现为变化多样的高低信号 ,T2 WI表现为高信号 ,PDWI表现为等及高信号。强化后囊性病灶表现为环状薄壁强化 ,实质性病灶为均匀强化。结论　多中心性颅咽管瘤的生长表现为以鞍区或鞍上区为中心的多点起源的生长特点 ,肿瘤的信号特点与病灶囊实性比例及囊液的成分有关     

颅咽管瘤的病理分型及MRI特征对比分析

目的：探讨不同组织类型的颅咽管瘤在MRI上的影像表现。材料和方法：回顾性分析经手术及病理证实的颅咽管瘤120例，结合常规MRI T1WI、T2WI、增强MRI表现，分析其发病部位、形态、大小、有夫脑积水、周围结构改变及信号特点，并根据最终病理结果进行对照分析。结果：不同组织类型的颅咽管瘤在MRI上均有各自的影像表现：成釉质细胞型常位于鞍上并可累及鞍内，多为囊性或囊实性，肿瘤可包绕蛛网膜下腔的血管；鳞状乳头型多位于鞍上，肿瘤为实性、囊实混合性和囊性，多见囊内结节；混合型表现类似成釉质细胞型，但可见囊内结节。结论：颅咽管瘤的MRI表现与其病理分型有一定相关性，其组织成分决定其在MRI上的特征表现。     

鞍区Rathke囊肿MRI诊断

目的:探讨鞍区Rathke囊肿的MRI表现,以提高对该病的认识。方法:回顾性分析11例经手术病理证实的鞍区Rathke囊肿MRI表现。结果:囊肿位于鞍内4例,鞍内向鞍上延伸6例,完全位于鞍上1例,多呈圆形、卵圆形或哑铃形,边界清楚,囊壁菲薄。T1WI、T2WI示囊液均为高信号2例;T1WI上呈高信号、T2WI上呈低信号2例;其余7例,T1WI呈等信号2例,呈低信号5例,T2WI均为高信号。囊内可见漂浮结节影5例,囊壁见线样增强1例。结论:典型鞍区Rathke囊肿MRI表现有一定特征性,结合临床表现,术前正确诊断是可能,但不典型病例需与鞍区垂体腺瘤、颅咽管瘤相鉴别。     

颅咽管瘤:MRI 和CT 表现及与病理对照

分析颅咽管瘤ＣＴ、ＭＲＩ特征,探讨影像学表现和病理间的联系,尤其是ＭＲＩ的Ｔ１高信号的产生基础,方法：ＣＴ及ＭＲＩ检查２１例颅咽管瘤患者,均经手术病理证实,囊液进行内容物的镜下分析。结论ＣＴ、ＭＲＩ相结合可以准确诊断颅咽管瘤,颅咽管瘤囊液内的高信号主要与囊液内的蛋白质有关,与胆固醇类物关系较小。     

鞍区囊性病变的MRI诊断

目的:探讨鞍区囊性病变的MR影像学表现,以提高认识和诊断水平。方法:32例经手术及病理证实的鞍区囊性病变包括16例垂体腺瘤囊变5、例Rathke囊肿、6例颅咽管瘤、3例垂体脓肿、2例表皮样囊肿,所有病例均行MRI平扫,22例行增强扫描。结果:囊性垂体腺瘤主要表现为长T1、长T2信号,14例有囊壁环形强化;Rathke囊肿、颅咽管瘤、垂体脓肿信号多变,与囊内容物有关;表皮样囊肿显示为与脑脊液信号相等的信号。结论:鞍区囊性病变的临床和MRI表现特点对提高诊断的正确性是有帮助的。     

鞍区囊性病变的MRI鉴别诊断

目的：探讨鞍区囊性病变的MRI表现，以提高对此类病变的鉴别诊断水平。方法：13例经病理证实的囊性病变包括垂体大腺瘤囊变1例、垂体大腺瘤囊变伴出血3例、垂体微腺瘤囊变伴出血2例、垂体微腺瘤囊变2例、颅咽管瘤3例、蛛网膜囊肿1例、表皮样囊肿1例、Rathke＇s囊肿1例。结果：鞍区病变以垂体瘤常见，以长／短T1．长T2信号为著，一般为厚壁且内壁不规则呈环形强化为主要表现；蛛网膜囊肿各序列呈脑脊液信号：颅咽管瘤、Rathke＇s囊肿信号较复杂。结论：应充分利用MRI软组织分辨率高、可多体位成像、多种序列扫描从病变生长部位、形态、生长方式、信号特点及其与周围组织的关系和临床表现进行综合分析，才能进行正确的诊断与肇别诊断。     

40例鞍区囊性病变的MRI鉴别诊断分析

目的分析囊性垂体瘤、囊性颅咽管瘤及Rathke囊肿的MRI表现,提高鞍区常见囊性病变的MRI诊断水平。资料与方法搜集40例经手术及病理证实的鞍区囊性病变患者的临床和影像资料,其中囊性垂体瘤12例,囊性颅咽管瘤13例,Rathke囊肿15例。全部病例均行MRI平扫和增强扫描。分析囊性病灶的位置、大小、囊壁厚度以及"束腰征"、海绵窦包绕等特殊征象。应用SPSS 11.0软件包,采用卡方检验对病灶的大小及囊壁的厚度进行统计学分析。结果病灶位于鞍上者仅见于囊性颅咽管瘤,鞍内且位于垂体前后叶之间仅见于Rathke囊肿。三者囊的大小和囊壁厚度差异均有统计学意义(χ2=17.65,P=0.0001;χ2=6.26,P=0.04)。无壁或薄壁者多见于颅咽管瘤和Rathke囊肿,占40%(10/25),厚壁者多见于囊性垂体瘤,占53%(8/15)。病灶直径≥2 cm多见于颅咽管瘤,占63%(12/19),<2 cm多见于Rathke囊肿,占61%(13/21)。颅咽管瘤和Rathke囊肿信号较复杂,而囊性垂体瘤除1例T1WI等信号,T2WI低信号外,其余11例均为T1WI低信号,T2WI高信号。"束腰征"主要见于囊性垂体瘤(6/7例),亦可见于Rathke囊肿(1/7例)。海绵窦包绕仅出现于囊性垂体瘤。壁结节可见于颅咽管瘤和Rathke囊肿(各2例),颅咽管瘤壁结节增强扫描明显强化,Rathke囊肿未见强化。结论根据囊性病灶的位置、形态、囊内MRI信号以及特殊征象,可对上述3种囊性病变进行鉴别。     

颅咽管瘤的MRI信号模式

目的：分组探讨信号强度与肿瘤组织类型及囊液成分之间的关系，加强对颅咽管瘤多样性表现的认识，资料与方法：搜集经手术病理证实的颅咽管瘤18例，常规作SE序列横断位T1WI，PDWI，T2WI及矢状位T1WI，全部病例均作增强扫描，部分病例囊液的生化分析，根据肿瘤在各序列上的信号强度，将颅咽管瘤的信号分为3种组合形式。结果：18例肿瘤散布在各个年龄阶段，全部病例均发生在鞍区，其中实性肿瘤2例，囊性肿瘤11例，以囊性为主的囊实性肿瘤5例，囊性肿瘤和肿瘤囊性成分的信号表现在不同的成像序列上十分复杂多变，T1WI从低信号到完全高信号不等，PDWI从等信号到完全高信号不等，T2WI均为高信号，根据各序列上的信号强度，肿瘤的信号表现可分为3种不同的组合模式。结论：肿瘤的信号特点与肿瘤继发改变及囊液的生化成分有关，与肿的组织亚型之间无明确的相关性。将肿瘤按信号特点分为3种表现模式，可以强化对颅咽管瘤的认识。指导临床诊断。     

MRI Features and Differential Diagnosis of Sellar Cystic Lesions

目的 分析囊性垂体瘤、囊性颅咽管瘤及Rathke囊肿的MRI表现,提高鞍区常见囊性病变的MRI诊断水平.资料与方法 搜集40例经手术及病理证实的鞍区囊性病变患者的临床和影像资料,其中囊性垂体瘤12例,囊性颅咽管瘤13例,Rathke囊肿15例.全部病例均行MRI平扫和增强扫描.分析囊性病灶的位置、大小、囊壁厚度以及“束腰征”、海绵窦包绕等特殊征象.应用SPSS 11.0软件包,采用卡方检验对病灶的大小及囊壁的厚度进行统计学分析.结果 病灶位于鞍上者仅见于囊性颅咽管瘤,鞍内且位于垂体前后叶之间仅见于Rathke囊肿.三者囊的大小和囊壁厚度差异均有统计学意义(x2＝ 17.65,P＝0.0001;x2＝ 6.26,P＝0.04).无壁或薄壁者多见于颅咽管瘤和Rathke囊肿,占40％(10/25),厚壁者多见于囊性垂体瘤,占53％(8/15).病灶直径≥2 cm多见于颅咽管瘤,占63％(12/19),＜2 cm多见于Rathke囊肿,占61％(13/21).颅咽管瘤和Rathke囊肿信号较复杂,而囊性垂体瘤除1例T1WI等信号,T2 WI低信号外,其余11例均为T1WI低信号,T2WI高信号.“束腰征”主要见于囊性垂体瘤(6/7例),亦可见于Rathke囊肿(1/7例).海绵窦包绕仅出现于囊性垂体瘤.壁结节可见于颅咽管瘤和Rathke囊肿(各2例),颅咽管瘤壁结节增强扫描明显强化,Rathke囊肿未见强化.结论 根据囊性病灶的位置、形态、囊内MRI信号以及特殊征象,可对上述3种囊性病变进行鉴别.     

Magnetic resonance imaging of pyomyositis in 43 cases

PURPOSE: To describe the magnetic resonance imaging (MRI) findings in pyomyositis. METHODS AND MATERIALS: Forty-three patients with proven muscle infection (30 males, 13 females) ranging in age from 14 to 86 years (mean 42 years) were studied with MRI. The initial clinical diagnose were soft tissue infection (n=27), neoplasm (n=12), thrombophlebitis (n=3), and lymphedema (n=1). Spin-echo T1- and T2-weighted images were obtained in all cases and STIR sequence in 6. Spin-echo T1-weighted images after Gd-DTPA injection were obtained in 16 cases. The signal intensity findings, the extent of the abnormalities in the soft tissue (muscle, fascial and subcutaneous involvement), the presence of fluid collections, and the involvement of neighbouring bone and joint were reviewed retrospectively. RESULTS: A hyperintense signal on T2-weighted and STIR images were detected in all patients. Fluid collections were seen in 21 cases as localized areas of hypointensity on the T1-weighted images, and highly hyperintense areas on the T2-weighted images. In four patients a rim of high signal intensity was seen around the fluid collection on the T1-weighted images. On contrast-enhanced T1-weighted images there was diffuse enhancement in the patients without fluid collections that was heterogeneous in seven and homogeneous in two. After Gd-DTPA all fluid collections showed a central area without enhancement and a well-defined enhancing peripheral rim. Involvement of adjacent structures included subcutaneous tissue (n=25), bone marrow (n=14), fascial planes (n=15) and joints (n=11). CONCLUSION: MRI is useful in the assessment of pyomyositis and in determining the location and extension. A hyperintense rim on unenhanced T1-weighted images and peripheral enhancement after Gd-DTPA are useful for identifying the number, size, and location of soft-tissue abscesses.     

卵巢内膜异位性囊肿的MRI诊断

目的：评价MRI诊断卵巢内膜异位性囊肿的价值。材料和方法：记录14例患者的25个痛灶MRI形态及信号变化特点，并与手术病理结果相对照．结果：发现当囊肿在T1WI上呈均匀高信号，T2 WI上部分区域出现中等至低信号暗影，或T1 WI病灶由多个全为高信号的囊腔组成时，不管其T2 WI上的信号强度如何．基本可确诊为卵巢内膜异位性囊肿．当囊肿在T1WI和T2WI上呈高信号．或囊肿与邻近器官有粘连，囊腔周围有纤维被膜包绕，在T1WL及T2WI上形成-低信号带影时．应高度怀疑之。结论：MRI对内膜异位性囊肿诊断的敏感性及准确性分别可选96%和93%．     

Hepatic adenomatosis: MRI demonstration with the use of superparamagnetic iron oxide

This case report describes a case of a 38-year-old woman with hepatic adenomatosis. MRI revealed five hyperintense nodular liver lesions on T1-weighted images which were hypo-isointense with the liver parenchyma on T2-weighted images. Serial gadolinium-enhanced images did not reveal distinctive imaging findings. With the use of superparamagnetic iron oxide (SPIO) particles, hyperintense adenomas revealed signal loss on T1-weighted images after SPIO. Two subcapsular adenomas were resected based on MRI findings and histopathology confirmed MRI diagnosis.     

葡萄膜黑色素瘤的MRI诊断

目的探讨MRI对葡萄膜黑色素瘤的诊断价值。资料与方法对35例葡萄膜黑色素瘤患者行MRI横断面、冠状面、斜矢状面平扫及增强扫描。结果35例黑色素瘤患者中27例在T1WI表现为高信号,8例为等信号,T2WI上均为低信号,增强后为中度至明显强化。21例继发的视网膜脱离在T1WI上为高信号,T2WI上为等或高信号,无强化。结论MRI可对肿瘤进行精确定位,同时能显示肿瘤的大小和信号特征,有助于对葡萄膜黑色素瘤的诊断及鉴别诊断。     

Atypical magnetic resonance imaging findings of craniopharyngioma

Three cases of craniopharyngiomas with atypical MRI findings are reported. The first patient had a nasopharyngeal craniopharyngioma. Its unusual location made diagnosis difficult. The second patient had a massive craniopharyngioma with extensive cystic expansion, involving the anterior, middle and posterior cranial fossae, and extending into the foramen magnum. The tumour of the third patient involved the suprasellar region with a large extension into the third ventricle, and demonstrated a predominantly high signal intensity on all T1-weighted, proton-weighted and T2-weighted images. These patients further stressed the complexity of MRI findings in craniopharyngiomas.     

Cross-sectional imaging of primary osseous hemangiopericytoma

The aim of this study was to assess cross-sectional imaging features and the value of CT and MRI in primary hemangiopericytoma of bone. In five patients with histologically proven primary osseous hemangiopericytoma CT and MR scans were evaluated retrospectively. Both CT and MRI were available in four patients each. In three patients both imaging techniques were available. On CT primary hemangiopericytoma of bone presents as an expansive lytic lesion with bone destruction and inhomogeneous contrast enhancement. Magnetic resonance imaging depicts osseous hemangiopericytoma as hyperintense lesion on T2-weighted images with intermediate signal intensity on T1-weighted images. Curvilinear tubular structures of signal void in the tumor matrix on T1-weighted images and corresponding hyperintense structures on T2-weighted and on fat-suppressed short tau inversion recovery images were present in three patients. Although cross-sectional imaging findings are non-specific, they add to the diagnosis and provide valuable information about the extent of bone destruction and local tumor spread in patients with primary osseous hemangiopericytoma. While CT demonstrates the extent of bone destruction best, MRI better visualizes medullary and soft tissue extension of the tumor. Curvilinear signal abnormalities support the diagnosis of hemangiopericytoma of bone. This imaging pattern is best visualized on fat-suppressed or contrast enhanced T1-weighted MR images.     

MRI of musculoskeletal extraspinal tuberculosis

PURPOSE: The aim of this study was to describe the MR findings in extraspinal musculoskeletal tuberculosis (EMT). METHOD: A retrospective review was conducted of the MR findings of 18 patients with microbiologically and/or pathologically proven EMT. All MR studies were performed using T1-and T2-weighted spin echo sequences. T1-weighted spin echo sequences after Gd-DTPA injection were obtained for 12 patients. The MR images were evaluated for abnormalities in joints, bones, and soft tissues, and the results were grouped by anatomic localization, frequency distribution of structures affected, and morphologic patterns of involvement. RESULTS: Isolated soft tissue tuberculosis was found in 10 (55.5%) patients and involvement of more than one structure in 8 (44.4%). Pyomyositis (n = 6) and arthritis with involvement of adjacent soft tissues (n = 7) were the most common forms of presentation. One patient presented with isolated fascial superficial tissue involvement in one leg. Isolated pyomyositis involving one (n = 3) or two (n = 3) muscles was homogeneous in six cases and showed intermediate (n = 6), low (n = 2), or high (n = 1) signal intensity on T1-weighted images and a high and very hyperintense signal on T2-weighted images. The tenosynovitis synovial fluid was homogeneous (n = 1) or heterogeneous with multiple tiny hypointense nodules (n = 1) on T2-weighted images. The subdeltoid bursitis fluid was characterized by homogeneous low signal intensity with a hyperintense rim (n = 2) on T1-weighted images and homogeneous (n = 1) or heterogeneous hyperintense signals with areas of low signal intensity (n = 1) on T2-weighted images. In tuberculous arthritis, the synovial joint fluid (n = 7) showed heterogeneous (n = 4) or homogeneous (n = 3) low signal intensity on T1-weighted images and high or very high signal intensity on T2-weighted images. Where involved, the adjacent muscle(s) (n = 8) were usually hypointense on T1-weighted images and very hyperintense on T2-weighted images. Associated cellulitis was found in arthritis with involvement of neighboring soft tissues (n = 5), pyomyositis (n = 2), and tenosynovitis (n = 1). The images obtained after Gd-DTPA showed peripheral (n = 10) or heterogeneous (n = 1) enhancement or no enhancement (n = 1). CONCLUSION: The MR findings for EMT are variable. Although diagnosis is dependent largely on prior presumption and clinical context, MRI provides valuable guidelines in defining the extent of the lesions to select the appropriate treatment and for follow-up of abnormalities.     

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.     

Craniopharyngioma: CT and MR imaging in nine cases

Magnetic resonance (MR) imaging and CT examinations were performed in nine patients with surgically proven craniopharyngioma. Computed tomography was found to be superior to MR in detection of calcification and cyst formation. Extent of involvement of adjacent structures (e.g., optic chiasm, third ventricle, and intracavernous carotid artery) was more clearly delineated by MR. Craniopharyngioma fluid collections were found to be uniformly bright on T2-weighted sequences. However, on T1-weighted sequences, the signal intensity of the fluid ranged from hypointense to hyperintense, reflecting the heterogeneous contents of cysts in these tumors. Since calcification and cyst formation are hallmarks of craniopharyngiomas, we believe that CT is more specific than MR in diagnosis of craniopharyngiomas. Magnetic resonance, however, offers a more accurate assessment of the tumor extent.     

MRI of hemangioblastoma in the conus medullaris.

Hemangioblastoma of the conus medullaris with MRI has not been reported before. A 75-year-old man had a history of falling due to weakness of his left lower limb. MRI revealed a well-defined oval mass in the conus medullaris. The tumor had an isointense signal relative to spinal cord on T1-weighted images, hyperintense signal areas intermixed with punctate spots of hypointensity on T2-weighted images, and heterogeneous obvious enhancement on gadolinium-enhanced T1-weighted images. Associated abnormally tortuous vessels were noted in the dura proximal to the tumor. Histological findings were compatible with the diagnosis of hemangioblastoma. Hemangioblastoma should be included in the differential diagnosis in patients with an enhancing tumor and adjacent engorged vessels of the spinal cord.