Rathke cleft cysts: CT, MR imaging, and pathologic features

The authors retrospectively reviewed the clinical, computed tomography (CT), and magnetic resonance (MR) imaging findings in seven patients with pathologically proved Rathke cleft cysts. All the cysts were located in the anterior sella turcica or the anterior suprasellar cistern. Five cysts had both intra- and suprasellar components, one was entirely intrasellar, and the other was predominantly suprasellar in location. The size of the cysts ranged from 8 to 20 mm. CT scans demonstrated low-density homogeneous lesions in four cases. On MR images of three of these four cases, the cysts had the same intensity as cerebrospinal fluid on T1- and T2-weighted images, while in the fourth case, the cyst was hyperintense on the T1-weighted images. In the remaining three cases, CT showed slight hyperdensity relative to brain parenchyma, suggestive of contrast enhancement. MR showed signal heterogeneity of these lesions with focal components of diminished signal intensity of T2-weighted images. These same foci appeared iso- to slightly hyperintense on T1-weighted images.     

脑膜型囊虫病的磁共振成像诊断

目的探讨磁共振成像(MRI)对脑膜型囊虫病的诊断价值。资料与方法回顾性分析经临床证实的21例脑膜型囊虫病的MRI表现特点。2l例均行MR平扫，7例同时行MR增强扫描。结果21例脑膜型囊虫病中，单纯性脑膜型囊虫8例(38．1％)，混合型13例(61．9％)。其中19例脑膜型囊虫多发，呈葡萄串状生长，2例单发，呈分叶状。囊虫发生于外侧裂9例，鞍上池6例，小脑桥脑角池4例，前纵裂池1例，同时发生于鞍上池与小脑桥脑角池1例。囊虫囊泡在T1WI上等于或稍高于脑脊液(CSF)信号，T2WI上等于CSF信号。囊泡壁在轴面T1WI上显示较为清楚，一般呈边缘光滑的细线样稍高信号影，增强后轻度强化；所有脑膜型囊虫内均未见头节显示。结论MRI是诊断脑膜型囊虫病的首选影像学检查方法。     

颅内表皮样囊肿的CT、MRI诊断

目的　分析颅内表皮样囊肿的CT、MRI表现。方法　对 18例经手术、病理证实的颅内表皮样囊肿的CT、MRI表现作了回顾性分析。 18例表皮样囊肿均作了MRI平扫和增强扫描 ,其中 12例还作了CT平扫检查。对肿瘤发生部位、大小、形态、CT密度、MRI增强前后的信号强度以及邻近结构的改变作了观察。结果　肿瘤位于桥小脑角区 10例 ,鞍上或鞍旁 3例 ,松果体区和第四脑室内各 2例 ,小脑延髓池 1例。肿瘤大小不等 ,形态多呈不规则形 ,轮廓光整或呈分叶状。CT平扫 10例呈均匀低密度 ,2例呈稍不均匀的低密度 ,CT值在 -15～ 10HU之间。在MRT1WI图像上肿瘤呈不均匀的低信号 ,在T2 WI、FLAIR图像上均呈不均匀的高信号。增强后除 1例肿瘤边缘似有轻微强化外 ,其余肿瘤均无明显的强化。结论　典型的颅内表皮样囊肿的CT、MRI表现较具特征性 ,通过CT、MRI检查可以作出准确诊断 ,并能与其他类似的颅内病变鉴别     

Dense suprasellar epidermoid cyst

A case of a dense epidermoid cyst of the suprasellar cistern is presented. The clinical symptoms were headache radiating to the left eye and a quadrant anopsia on the left eye. The density of the epidermoid was 62 HU and no significant contrast enhancement occurred after contrast application. The main feature which allows differentiation from other hyperdense suprasellar lesions seems to be the lack of contrast enhancement.     

Unique MR spectroscopic finding in colloid-like cyst

Cysts morphologically identical to colloid cysts are rarely reported to be located in areas outside the third ventricle. We report the magnetic resonance (MR) imaging and spectroscopic findings in three patients with colloid like cyst located in the ponto-medullary, pre-pontine cistern and suprasellar region. The MR imaging and spectroscopy performed on a 1.5-tesla scanner in three female patients revealed T1 hyperintense mass lesions. A large dominant metabolite peak at 2.0-ppm chemical shift, simulating N-acetylaspartate (NAA) of normal neuronal tissue was detected within the lesion.This peak is probably due to the presence of glycoproteins secreted by the ciliated columnar epithelium lining these cysts. MR spectroscopy of colloid cyst has not been described in the literature and hence the findings in this study will help in the diagnosis of this cystic lesion especially when located at unusual location. The signal characteristics of these cysts in various sequences including diffusion weighted imaging (DWI) and susceptibility weighted imaging (SWI) are also discussed.     

颅咽管瘤的CT分析

本文回顾性分析了６５例颅咽管瘤的ＣＴ表现。颅咽管瘤可分为囊性（包括单囊性与多囊性）、囊实性和实性肿瘤。本组囊性肿瘤３９例，占６０％，其中多为低密度，少数为等密度或高密度。增强扫描囊内无强化。鞍上池内囊性病变囊壁钙化、边缘强化是本病的特征表现。多囊性也是本病的特征表现。囊实性肿瘤１８例，占２７．７％，表现为部分囊性、部分实性，囊性部分仍具有囊性颅咽管瘤的特征。实性肿瘤８例，占１２．３％，有时实性肿瘤     

Hyperprolactinemia: an unusual manifestation of suprasellar cystic lesions

Two patients with suprasellar cysts and hyperprolactinemia are described. These lesions were diagnosed by CT metrizamide cisternography. Suprasellar cysts are a rare cause of pathologic hyperprolactinemia, which most commonly results from pituitary adenomas. Tissue diagnosis revealed suprasellar arachnoid cysts in the first patient and Rathke's cleft cyst in the second. The differential diagnosis of suprasellar cysts is presented, and distinguishing radiographic characteristics are discussed.     

小脑幕切迹下疝的CT诊断

目的 确定小脑幕切迹下疝的CT表现。方法 回顾性分析经临床证实的68例小脑幕切迹下疝的CT表现。结果 CT显示因脑组织移位及中脑本身受压移位导致单侧或双侧鞍上池改变60例、脚间池改变56例、环池改变52例、四叠体池改变50例。多数为前疝和半环疝。均有脑干的移位、旋转及变形改变，可伴有四脑室的变窄、闭塞及幕上占位病变的一系列改变。结论 参考原发病变的占位程度，脑干与脑干周围脑池两CT改变均存在并结合起来分析，可作出正确诊断。     

原发性囊腔型肺癌的CT诊断13例诊断分析

目的探讨原发性囊腔型肺癌的CT表现,以提高对本病的诊断准确率。方法回顾性分析经病理证实的13例原发性囊腔型肺癌的CT表现。结果13例囊腔型肺癌均为单发病例,左肺5例,右肺8例,其中10例腺癌,2例鳞癌,1例小细胞肺癌。病灶边缘分叶、毛刺分别占61.5%、76.9%;囊内壁毛糙、厚薄不均分别占84.6%、92.3%;囊内分隔占61.5%;囊腔内壁结节占53.8%;病变周围胸膜凹陷和血管集束分别占69.2%、84.6%。8例增强检查病例中6例轻度强化,2例中度强化。动态随访病例中,1例壁结节增大,1例囊腔增大,2例囊腔及实性成分均增大。结论囊腔内壁毛糙,囊内分隔及壁结节是有助于囊腔型肺癌诊断的特征性征象,有助于其鉴别诊断。     

MR imaging of pineal cysts

Identification of pineal cysts with imaging modalities other than magnetic resonance (MR) has been infrequent, despite a reported autopsy incidence of as high a 40%. We recently identified 15 patients in whom pineal cysts were seen on MR. These cysts ranged from 5 to 15 mm in maximum diameter. The cyst walls were thin, usually measuring less than 2 mm. The signal characteristics of the fluid within the cysts paralleled that of CSF, although it differed somewhat in signal intensity from CSF collections in which there was pulsatile motion. All lesions were midline in location. There was no significant mass effect, although mild flattening of the superior colliculi could be seen. Two cases were operated on; at operation, typical pineal cysts were found, with one containing hemosiderin-laden proteinaceous material, which accounted for its markedly higher signal intensity. It is important that this entity be recognized so that these lesions are not confused with pineal tumors.     

Benign liver lesions: implications of detection in cancer patients

A review of liver sonograms obtained for cancer patients (excluding primary liver cancers) over a 12 year period found 829 benign lesions: non-parasitic cysts (427 cases), hemangiomas (216 cases), solitary calcifications (79 cases), focal fatty infiltration (62 cases), and miscellaneous lesions (45 cases). These benign pathologies represented 41.8% of the focal hepatic lesions observed during this period in this population; hepatic metastases accounted for the remaining 58.2%. Marked female predilection was noted for the nonparasitic cysts, hemangiomas, and focal fatty infiltration; 63–78.7% of these lesions were solitary, and first-line imaging by US was sufficient for diagnosis of 66.1–98.2% of cases. Analysis of lesion evolution over more than 5 years revealed modifications in 17% of hemangiomas, 23.9% of nonparasitic cysts, and 75% of cases of focal fatty infiltration. Systematic pretherapy liver sonography can be proposed owing to the high frequency of benign liver lesions that can create diagnostic problems during follow-up of cancer patients. Correspondence to: J. N. Bruneton     

MRI of intracranial germ cell tumors

We reviewed MRI findings in proven intracranial germ cell tumours in 22 cases, 12 of whom received Gd-DTPA. On T1-weighted images, the signal intensity of the tumour parenchyma was moderately low in 19 cases and isointense in 3; on T2-weighted images, it was high in all cases. Regions of different intensity thought to be cysts were found in 17 (77%): 7 of 12 patients with germinoma (58%) and in all other cases. Of the 13 patients with pineal lesions T1-weighted sagittal images showed the aqueduct to be obstructed in 5, stenotic in 7 and normal in 1. Strong contrast enhancement was observed in all 12 cases. Of the 14 patients with suprasellar lesions, 5 were found to have an intrasellar extension, and in 3 of these, the normal pituitary gland, which could be distinguished from the tumour, was displaced anteriorly. Ten patients (45%) had multiple lesions.     

Brain atrophy in 18 patients with Down syndrome: a CT study

Individuals with Down syndrome develop neuropathologic and in some cases clinical evidence of Alzheimer disease after age 40. We compared CT scans of 18 Down syndrome subjects, 26-70 years old (seven of whom satisfied criteria for dementia), with 175 screened normal volunteer control subjects for evidence of cortical and subcortical atrophy. CT scans were analyzed as a function of age and cognitive status. The suprasellar cistern ratio, presumed to measure mesial temporal-lobe atrophy (or hypoplasia), was correlated with severity of cognitive impairment, even when age effects were removed. The suprasellar cistern ratio predicted dementia status with an accuracy of greater than 75%. Brain measurements on CT scans showed a distinct pattern of increased abnormality with age in patients with Down syndrome; this differed clearly from that seen in controls.     

中枢神经系统肠源性囊肿的MR诊断与鉴别诊断

目的探讨中枢神经系统肠源性囊肿的MRI表现及其鉴别诊断。方法回顾性分析7例经手术和病理证实的肠源性囊肿的临床和MRI资料。结果 7例肠源性囊肿,桥前池1例,椎管内髓外硬膜下6例,3例病变位于颈段,2例位于上段胸段,1例位于腰段。6例椎管内肠源性囊肿,5例囊肿位于脊髓腹侧,均可见"脊髓嵌入征"。多数囊肿T1Wl呈等或稍高于脑脊液信号,T2WI等或稍低于脑脊液信号。6例行MR增强扫描,5例囊壁及囊液均未见强化,1例囊壁轻度强化。结论 MRI对肠源性囊肿的诊断及鉴别诊断有重要价值。     

含囊腔的周围型肺癌的 MDCT 特征分析

目的：分析含囊腔的周围型肺癌的 MDCT 特征,提高诊断准确性。方法回顾性分析经病理或临床证实的21例含囊腔的周围型肺癌患者的临床资料、病理类型、TNM 分期、MDCT 表现,部分行 PET-CT 检查的,测量 SUMmax,随访的病例,评价病灶的动态变化。结果共21例(病理诊断证实腺癌11例、鳞癌6例),囊腔为主型2例(9.52%);囊性与磨玻璃密度混合型3例(14.29%);囊性与实性密度混合型14例(66.67%);囊性与磨玻璃、实性密度混合型2例(9.52%)。有软组织结节的20例,结节位于腔外5例(23.81%);结节位于腔内1例(4.76%);多房囊腔与结节混合型14例(66.67%);囊腔壁环形增厚1例(4.76%)。MDCT 征象出现60%以上的有：圆形/类圆形14例(66.67%),分叶征17例(80.95%),腔内血管穿行16例(76.19%),胸膜凹陷征17例(80.95%);出现率90%以上的征象有：多囊19例(90.48%)、不规整19例(90.48%),囊腔内见分隔19例(90.48%)。支气管通入囊腔内8例(38.10%)。病灶 CT 净增值范围14.2~40 HU,平均(28.27±7.27)HU。PET-CT SUVmax 范围4.5~9.8,平均6.05,均呈明显摄取。2例患者随访出现囊腔增大,囊壁增厚。1例患者随访囊腔缩小,实性成分增多。结论囊腔内壁不规整、腔内分隔及血管穿行是诊断含囊腔周围型肺癌的重要征象。     

Characteristics of Rathke's cleft cyst in MR imaging.

PURPOSE: Symptoms, macroscopic appearances and microscopic findings of Rathke's cleft cysts with magnetic resonance (MR) imaging. Patients and METHODS: We analyzed the data from 31 patients with pathologically confirmed Rathke's cleft cysts. MR appearances were evaluated on T1WI, T2WI and contrast T1WI. Symptoms, macroscopic appearances and pathological findings were obtained from available medical records. We analyzed the images according to the following criteria: 1. findings on the location and shape of the lesions and form of the lesional wall; 2. the relationship between the maximum diameter of the lesions and symptoms; 3. the relationship between MR and macroscopic appearance; 4. the sites of adjacent contrast enhancement. RESULTS: The lesions were located mostly in both the intrasellar and suprasellar regions for a total of 87%. All lesions revealed either an oval or dumbbell shape with a smooth lesional wall. When correlated with physical symptoms, asymptomatic cases were associated with smaller lesions, while visual disturbances and dizziness were associated with relatively larger lesions. MR lesion signal intensity was related to the content of macroscopic appearance to some degree: the selected lesions showed shortening of T1 and T2 relaxation times in relation to the increase in protein concentration. This should have been macroscopically reflected in the color and turbidity of the liquid within the cyst. Adjacent contrast enhancement around the lesion was found at various sites, but anterior enhancement was most frequent. Circumferential enhancement was revealed to be derived from inflammatory changes. CONCLUSION: Rathke's cleft cyst exhibits a varied MR signal. It may be difficult to differentiate from craniopharyngioma from the intensity alone.     

鞍区肿瘤的MRI表现与鉴别诊断

目的：明确不同类型鞍区肿瘤的MRI特征。材料与方法：回顾性分析44例经手术病理证实的鞍区肿瘤MRI表现。结果：19例垂体大腺瘤、12例颅咽管瘤、9例鞍区脑膜瘤及4例鞍上池表皮样囊肿均有其一定的特征性MRI表现。垂体大腺瘤起源于垂体，大多数向上生长呈“雪人”形，个别向下生长突破鞍底，瘤体内可发生囊变（47％）或出血（32％）而致信号强度不均；颅咽管瘤多发生于鞍上，少数累及鞍内，囊实性或囊性者居多，其中于T1加权像上囊液可呈低、等、高不同信号强度为其特点；脑膜瘤多位于鞍上池前部，信号均匀与脑灰质相似，增强扫描有时可见脑膜尾征；发生于鞍上池的表皮样囊肿沿脑池生长，边缘不规则，信号强度与脑脊液相似。结论：MRI对鞍区肿瘤有重要的鉴别诊断价值。     

脑内囊性增强病变的CT研究

目的研究脑内环形增强病变脑脓肿、脑胶质瘤、脑转移瘤CT影像的诊断价值。材料和方法对27例脑脓肿、67例脑胶质瘤和39例转移瘤的分布、数目、囊壁的形态及蛛网膜下腔的播散等进行比较和分析,研究鉴别诊断的可能性。结果脑脓肿和转移瘤倾向于分布皮髓交界处,分别占85％和86％。单发以胶质瘤为多见。脑脓肿壁较规则,占94％。9个(26％,9/34)脑脓肿壁还呈独特的口袋状形态。蛛网膜下腔播散以脑脓肿最多见,占21％(7/34),胶质瘤次之10%(7/69),本组转移瘤未显示此征像。结论囊壁的形态、部位、蛛网膜下腔的播散征像有助于鉴别诊断。     

小脑幕切迹疝CT诊断及临床价值

目的:探讨小脑切迹疝的CT早期表现及临床应用价值。方法:对临床诊断为小脑切迹疝75例CT表现和临床分型进行分析。结果:小脑切迹疝CT表现鞍上池、脚间池、环池、四叠池缩小变形或闭塞分别占52/75、52/75、47/75、20/75。中脑变形移位33/75,脑室系统扩张(侧、三脑室)7/75,蛛网膜下腔出血占26/75。临床分前疝、后疝、全疝、环疝,各占24/75、31/75、16/75、4/75。行脑定位抽吸术治疗27例,外科手术34例。结论:小脑切迹疝CT表现具有特征性,脑疝早期可无典型脑疝临床表现,而CT检查可早期诊断,且优于其他检查。     

颅内巨大动脉瘤的MRI影像学分析

目的：评价MRI对颅内巨大动脉瘤的诊断价值。方法：搜集经血管造影或手术证实的21例颅内巨大动脉瘤,MR扫描使用3.0TMR系统,FSE和SE脉冲序列。结果：动脉瘤大小为2.5～8.1cm,位于鞍旁10例、鞍上4例、侧裂池3例、后颅窝3例、额顶部1例。载瘤动脉来源于颈内动脉11例、大脑前动脉A1与A2段交界处3例、大脑中动脉M1与M2交界处3例、椎基底动脉3例、大脑前动脉A3段1例。11例伴不同程度的血栓表现为瘤体周边不均匀混杂信号。MRI对伴有血栓形成的动脉瘤实际瘤体大小的显示均优于MRA和DSA。结论：MRI在颅内巨大动脉瘤诊断中对瘤体大小、瘤体内部有无血栓形成及瘤体周围的改变明显优于MRA和DSA。临床疑似颅内动脉瘤时不应只进行MRA或DSA检查。