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.     

鞍区囊性病变的MRI影像学表现

目的：探讨鞍区囊性病变的MRI影像学表现,以提高对此类病变的诊断水平。方法：37例鞍区囊性病变包括垂体腺瘤囊变16例、囊性颅咽管瘤5例、Rathke＇s囊肿5例、表皮样囊肿3例、蛛网膜囊肿5例、垂体脓肿3例。所有病例均行MRI平扫,其中32例行增强扫描。结果：鞍区病变以垂体瘤囊变最常见,主要表现为T1WI低信号,T2WI高信号,囊壁强化;颅咽管瘤、Rathke＇s囊肿信号较复杂,与囊内容物有关;蛛网膜囊肿、表皮样囊肿显示为与脑脊液信号;垂体脓肿增强扫描囊壁呈明显环形强化。结论：鞍区不同囊性病变具有一定MRI表现特点,结合临床病史多数病变可做出正确诊断。     

Maximum likelihood method in MRI diagnosis of cystic lesions involving sellar region

目的:探讨最大似然法对囊性垂体瘤、Rathke囊肿和颅咽管瘤这3种鞍区囊性病变的鉴别诊断价值.方法:对经手术病理证实的84例鞍区囊性病变的MRI资料进行回顾性分析,其中囊性垂体瘤40例,颅咽管瘤29例,Rathke囊肿15例.选出10个常见MRI征象,应用最大似然法进行判别,将其结果与常规阅片法的诊断结果进行比较.结果:采用最大似然法84例鞍区囊性病变的诊断符合率分别为囊性垂体瘤87.5％(35/40)、颅咽管瘤93.1％(27/29)和Rathke囊肿80.0％(12/15),总的诊断符合率为88.1％(74/84);常规阅片法诊断符合率分别为囊性垂体瘤80.0％(32/40)、颅咽管瘤86.2％(25/29)和Rathke囊肿60.0％(9/15),总诊断符合率为78.6％(66/84).最大似然法诊断符合率略高于常规阅片法,但两者差异无显著性意义(x2 =2.74,P=0.098).结论:最大似然法对鞍区囊性病变的诊断有较高的准确性,可用于指导日常阅片工作,尤其是年轻医师或基层医院医师的工作.     

最大似然法在鞍区囊性病变MRI诊断中的价值初探

目的:探讨最大似然法对囊性垂体瘤、Rathke囊肿和颅咽管瘤这3种鞍区囊性病变的鉴别诊断价值。方法:对经手术病理证实的84例鞍区囊性病变的MRI资料进行回顾性分析,其中囊性垂体瘤40例,颅咽管瘤29例,Rathke囊肿15例。选出10个常见MRI征象,应用最大似然法进行判别,将其结果与常规阅片法的诊断结果进行比较。结果:采用最大似然法84例鞍区囊性病变的诊断符合率分别为囊性垂体瘤87.5%(35/40)、颅咽管瘤93.1%(27/29)和Rathke囊肿80.0%(12/15),总的诊断符合率为88.1%(74/84);常规阅片法诊断符合率分别为囊性垂体瘤80.0%(32/40)、颅咽管瘤86.2%(25/29)和Rathke囊肿60.0%(9/15),总诊断符合率为78.6%(66/84)。最大似然法诊断符合率略高于常规阅片法,但两者差异无显著性意义(χ2=2.74,P=0.098)。结论:最大似然法对鞍区囊性病变的诊断有较高的准确性,可用于指导日常阅片工作,尤其是年轻医师或基层医院医师的工作。     

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。     

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。     

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     

Rathke囊肿的CT和MRI诊断(附6例报告)

为丰富CT和MRI对Rathke囊肿的认识,便于诊断,对经手术病理证实的6例患者与CT和MRI检查对照分析.结果显示,术前CT、MRI误诊为颅咽管瘤、垂体瘤、胆脂瘤等.CT显示圆形及不规则形囊性低密度区4例,圆形等密度和稍高密度区各1例,强化后2例囊壁线状增强.MRI显示圆形及类圆形T1WI像低信号3例,等信号1例;T2WI像均为高信号,边缘清楚.提示MRI对本病的诊断价值优于CT.     

Rathke囊肿的CT5和MRI诊断（随6例报告）

为丰富CT和MRI对Rathke囊肿的认识，便于诊断，对经手术病理证实的6例患者与CT和MRI检查对照分析。结果显示，术前CT、MRI误诊为颅咽管瘤、垂体瘤、胆脂瘤等，CT显示圆形及不规则形囊性低密度区4例，圆形等密度和稍高密度区各1例，强化后2例囊壁线状增强，MRI显示圆形及类圆形T1WI像低信号3例，等信号1例；T2WI像均为高信号，边缘清楚，提示MRI对本病的诊断价值优于CT。     

Pituitary adenoma, craniopharyngioma, and Rathke cleft cyst involving both intrasellar and suprasellar regions: differentiation using MRI

AIMS: To determine the differential magnetic resonance imaging (MRI) features of pituitary adenoma, craniopharyngioma, and Rathke cleft cyst involving both intrasellar and suprasellar regions. MATERIALS AND METHODS: The MRI images of 64 patients with pituitary adenoma (n=38), craniopharyngioma (n=13), or Rathke cleft cyst (n=13) were retrospectively reviewed by three neuroradiologists. The following characteristics were evaluated: shape, volume, extent, component characteristics, signal intensities of solid portions on T2-weighted images, signal intensities of cystic portions on T1-weighted images, and enhancement patterns of solid portions and cyst walls of tumours. Fisher's exact test applied with Bonferroni correction was used for multiple comparison. A flowchart for differential diagnosis was constructed based on statistical analysis of the results. RESULTS: A snowman shape, solid characteristics, and homogeneous enhancement of the solid portion were more common in pituitary adenomas (p<0.017). A superiorly lobulated shape, third ventricle compression by superior tumour extension, mixed solid and cystic characteristics, and reticular enhancement of the solid portion were more common in craniopharyngiomas (p<0.017). Finally, an ovoid shape, a small tumour volume, cystic characteristics, and no or thin cyst wall enhancement were more common in Rathke cleft cysts (p<0.017). The flowchart yielded diagnostic accuracies as follows: 92.1% in pituitary adenoma; 92.3% in craniopharyngioma; 92.3% in Rathke cleft cyst; and 92.2% overall. CONCLUSION: A combination of MRI findings is helpful in the differential diagnosis of the three tumours involving both intrasellar and suprasellar regions.     

不典型颅咽管瘤的MR诊断和误诊分析

目的 探讨不典型颅咽管瘤的MR表现,提高诊断的准确率.方法 回顾性分析8例经手术病理证实不典型颅咽管瘤的MR资料.结果 8例中囊性病灶3例,实性病灶2例,囊实性病灶3例.囊性病灶T1信号多变,囊壁明显强化且菲薄均匀;实性病灶扩散加权成像(DWI)序列呈低信号,增强呈"网格状"明显强化;囊实性病灶不均匀明显强化.4例鞍内鞍上型病灶,因正常垂体显示不清误诊为垂体瘤;2例鞍上型病灶,因瘤体明显强化误诊为生殖细胞瘤;2例鞍上型病灶,因与垂体柄、视交叉分界不清误诊为鞍区毛细胞型星形细胞瘤.结论 不典型颅咽管瘤的MR影像特征有助于其与垂体大腺瘤、生殖细胞瘤和毛细胞型星形细胞瘤相鉴别.     

鳃裂囊肿的MRI和CT诊断

目的：讨论鳃裂囊肿的ＭＲ和ＣＴ表现及其诊断价值。方法：对均经手术和病理证实的１１例鳃裂囊肿病人（第一鳃裂囊肿２例,第二鳃裂囊肿９例）的ＣＴ或ＭＲＩ的表现进行分析,并结合文献进行讨论。结果：第一鳃裂囊肿表现为耳前区反复感染或瘘,其特征为瘘道与外耳道平行;第二鳃裂囊肿常表现为颈外侧部和颌下区无压痛囊性肿块,ＣＴ和ＭＲＩ表现为薄壁、均质的囊性肿块,胸锁乳突肌受压向后外或向后移位,颈动脉间隙大血管向内或向     

MR imaging of the sellar and juxtasellar regions

Multiplanar capability and superior tissue contrast differentiation render magnetic resonance (MR) imaging the preferred method for examining patients with pituitary axis dysfunction or visual field deficits. In a review of 131 sellar or juxtasellar abnormalities, 76% were common lesions with distinctive features that helped establish their diagnosis: macroadenoma (n = 51), microadenoma (n = 20), meningioma (n = 14), craniopharyngioma (n = 10), and aneurysm (n = 5). On T1-weighted images, microadenomas were usually hypointense relative to normal pituitary gland, and macroadenomas and meningiomas were isointense relative to gray matter. Both microadenomas and meningiomas were more conspicuous immediately after contrast material administration. Craniopharyngiomas were the most heterogeneous of all the sellar lesions due to their cystic and solid components. MR images of aneurysms showed flow void and heterogeneous increased signal intensity in areas of slower turbulent flow. Other characteristics such as extrasellar versus intrasellar location, nature of contrast material enhancement, the presence of cystic components, and clinical findings permitted differentiation among less common lesions, including granulomatous disease, metastases, chiasmatic glioma, arachnoid cyst, hypothalamic glioma, schwannoma, germinoma, epidermoid, Rathke cyst, chordoma, chondrosarcoma, colloid cyst, and hamartoma.     

鞍区肿瘤的MRI诊断

目的:评价鞍区肿瘤的MRI影像特征,探讨MRI对该区肿瘤的诊断价值。方法:收集经手术与病理证实的鞍区肿瘤63例,其中垂体瘤35例,脑膜瘤6例,颅咽管瘤14例,脊索瘤7例,表皮样囊肿1例。全部病例行MRI平扫检查,52例行增强检查。结果:MRI检查,T1WI上肿瘤大多呈低、等信号或混杂信号,T2WI上呈均匀高信号或不均匀高低混杂信号。结论:MRI对鞍区肿瘤的诊断与鉴别诊断具有重要临床价值。     

Concomitant pituitary adenoma and Rathke's cleft cyst

We reviewed the clinical, radiological and surgical findings in patients with both pituitary adenoma and Rathke's cleft cyst. We retrospectively selected patients with both lesions from the 374 patients in whom a sellar/juxtasellar lesion was detected on MRI at 1.5 tesla. All patients received intravenous contrast medium. Concomitant pituitary adenoma and Rathke's cleft cyst were found in eight patients (2.1 %). The frequency of the combination was 3.5 % of pituitary adenomas and 11 % of Rathke's cleft cysts. Symptoms were always due to the adenoma, secreting adrenocorticotrophin in two patients and growth hormone in six. The adenoma was larger in five patients, and the cyst in three. The cysts gave variable signal. The adenoma was adjacent to the cyst in seven patients, and enclosed it in the other patient. As a result of experience with MRI, concomitant pituitary adenoma and Rathke's cleft cyst are now known not to be as rare as thought previously. When a nonenhancing cyst-like structure is demonstrated in a patient with pituitary adenoma, the possibility of a coexisting Rathke's cleft cyst should be considered. Received: 23 March 2000/Accepted: 12 July 2000     

Intrasphenoidal rathke cleft cyst

Symptomatic Rathke cleft cysts (RCC) are reported in the sellar and suprasellar regions, but no case of sphenoidal RCC has been reported. We report a case of sphenoidal RCC in a 41-year-old man. The lesion was revealed by headaches and diplopia. Symptoms disappeared transiently after a spontaneous rhinorrhea but relapsed 4 months later. MR imaging showed a cystic sphenoidal lesion, isointense on T1-weighted images (WI) with peripheral gadolinium enhancement and hyperintense on T2 WI. The patient underwent surgery through a transrhinoseptal approach. The wall of the sphenoid sinus was paper-thin. The cyst contained a motor-oil-like fluid and communicated widely with the nasal fossa. Its wall was partially extracted. Symptoms and signs ceased after surgery. MR imaging performed 1 year later showed the disappearance of the sphenoidal cyst. Embryological origin of RCCs is discussed. The hypothesis of a continuum between the different epithelial cystic lesions of the sellar and parasellar region is discussed. Imaging has an important impact on the diagnosis; nevertheless, the specific characterization remains difficult.     

MRI in the diagnosis of Rathke's cleft cyst

PURPOSE: Rathke's cleft cysts are non neoplastic lesions of the sellar area that seldom are symptomatic. Their incidence has been underestimated before magnetic resonance imaging (MRI). The aim of this work was to assess the value of MRI in the diagnosis and differential diagnosis of Rathke's cleft cyst based on a retrospective review of 12 cases and a review of the literature. PATIENTS AND METHODS: We retrospectively reviewed the MRI features of 12 patients with Rathke's cleft cyst collected over 4.5 years. Patients included ten females and two males (mean age: 39 years). The most common presentation was the association of dysmenorrhea and pituitary dysfunction. MRI examinations were performed using a 1.5 Tesla system, T1 and T2 weighted sequences performed before and after Gd- DTPA injection. Signal intensity, shape, size and location of the lesion were analyzed. RESULTS: In all cases, MRI examination showed a cystic lesion of variable size and signal intensity. The cyst was purely intrasellar in nine cases and a suprasellar extension was noted in three cases. Five patients underwent surgery providing pathological confirmation, four underwent routine follow-up and three were lost of follow-up. CONCLUSION: We conclude that MRI is an efficient tool for diagnosis, allowing appropriate medical decision making.