脑室内肿瘤的CT和MR诊断及鉴别诊断

目的 :评价和探讨脑室内肿瘤的CT和MR诊断价值。方法 :经手术病理证实的脑室肿瘤 32例 ,回顾性分析其CT和MR表现。结果 :脑室肿瘤与发病年龄和发病部位关系密切并且具有一定影像特征。CT显示肿瘤钙化较佳 ,对肿瘤的鉴别诊断帮助很大。MR可以三维成像 ,可以准确显示肿瘤的位置及邻近情况。结论 :脑室肿瘤的诊断主要依靠其CT和MR表现 ,结合年龄特征和发病部位 ,可进一步提高诊断准确率。     

Thrombosis of the deep cerebral veins: CT and MRI findings with pathologic correlation

Deep cerebral vein thrombosis can present with acute, severe neurological symptoms and may be rapidly fatal as in the 20-year-old woman reported here. Although MRI is superior for establishing the diagnosis, CT is usually the first examination performed in the clinical setting. It is therefore important to recognise certain indicators such as extensive bithalamic low density. These and certain other less specific signs are correlated with the MRI and autopsy findings. Received: 14 October 1996 Accepted: 7 February 1997     

MRI of patients with cerebral palsy and normal CT scan

Summary Three children with clinical evidence of cerebral palsy (CP) and normal cerebral computed tomography (CT) scans were evaluated by magnetic resonance imaging (MRI) to identify CT-undetectable white matter lesions in the watershed zones of arterial territories. The two patients with spastic diplegia showed bilateral lesions either in the subcortical regions or in the occipital periventricular regions. The patient with congenital hemiplegia exhibited unilateral lesions in the periventricular region. We conclude that MRI is more informative than CT for the evaluation of patients with CP.     

Disseminated mucormycosis in haematological patients: CT and MRI findings with pathological correlation

Disseminated mucormycosis is a rare, mostly fatal infectious complication in immunocompromised haematological patients. The purpose of our study was to describe the multiorgan manifestations of disseminated mucormycosis documented at CT and MRI in four patients and correlate these with the pathological findings and patient outcome. Irrespective of the site of infection, infarction or haemorrhage are the constant features of invasive mycosis. Identification of one or both of these two major imaging findings in immunocompromised patients should be regarded as an indicator of possible infection by angiotropic fungi, including the genre Mucorales.     

脑灌注MRI与脑血管造影在评价脑缺血病变中的价值

目的 通过对脑缺血性疾病患者的脑动脉血管造影和脑灌注ＭＲＩ对照，评价脑缺血性疾病中侧支循环建立情况，并试图鉴别脑缺血性病变的性质。     

肾上腺间质组织肿瘤的CT和MRI表现

目的 分析５例罕见的肾上腺质组织肿瘤的ＣＴ和ＭＲＩ表现。方法 对５例经手术和病理证实的肾上腺间质组织肿瘤的ＣＴ和ＭＲＩ表现进行回顾性分析。其中右肾上腺神经纤维瘤２例,右肾上腺神经鞘瘤１例,左肾上腺纤维脂肪瘤１例,双侧肾上腺脂肪瘤１例。结果１例神经纤维瘤和１例神经鞘瘤有大的囊空区,１例神经纤维瘤显示多发性钙化和片状的增强。１例纤维脂肪瘤为Ｔ１ＷＩ低信号,Ｔ２ＷＩ稍高信号,注射钆剂后明显增强。１例双     

Epithelial tumors of the ovary: CT findings and correlation with US

One hundred thirty patients with 170 epithelial ovarian tumors were prospectively studied with computed tomography (CT) before surgery. Ultrasound (US) was performed in 108 patients with 138 tumors. At pathologic examination, 78 tumors (46%) were benign, 14 (8%) borderline, and 78 (46%) malignant. CT results were compared with surgical and pathologic findings in all patients. CT enabled detection of 148 of 170 tumors (87%), and US enabled detection of 118 of 138 tumors (86%). Benign serous cystadenomas (n = 42) were correctly characterized with a sensitivity of 69% at CT and 70% at US. Benign mucinous cystadenomas (n = 21) were correctly characterized with a sensitivity of 62% at CT and 50% at US. Malignancy was suggested in nine of 14 patients (64%) with borderline tumors at CT and in five of 14 (36%) at US. The overall accuracy of characterization of benign versus malignant tumors (including borderline tumors) was 94% with CT and 80% with US. In the 108 patients studied with both CT and US, the sensitivity of CT was significantly superior to that of US (P less than .03), whereas there was no significant difference in specificity (P = .125).     

节细胞神经瘤的CT、MRI表现与病理对照分析

目的 分析节细胞神经瘤的CT与MRI表现以及与病理的对照.方法 回顾性分析经手术病理证实的11例节细胞神经瘤的CT与MRI表现及临床病理资料,11例全部行CT检查,其中4例同时行MRI检查.结果 11例节细胞神经瘤大小范围在3cm×4cm×4cm～6cm×7.8cm× 8.5cm之间.肿瘤形态表现为边界清楚的椭圆形肿块,亦可呈不规则形,沿冠状轴生长,可对邻近大血管包绕1/2以上.CT平扫表现为水样至肌肉样密度,多表现低密度,其内散在点状或结节状钙化,不增强或轻度增强居多.MRI T1WI为低信号,T2WI为不均匀混杂信号,但以高信号为主;动态增强扫描中,肿瘤早期不强化,并呈逐渐强化的特征,肿瘤包膜可强化.结论 节细胞神经瘤的CT与MRI表现有一定特征性,并与病理中肿瘤富含大量黏液基质呈相关性.     

Uncommon adrenal masses: CT and MRI features with histopathologic correlation

Adrenal glands are common sites of diseases. With dramatically increased use of computed tomography (CT) and magnetic resonance (MR) imaging, more and more uncommon adrenal masses have been detected incidentally at abdominal examinations performed for other purposes. In this article, uncommon adrenal masses are classified as cystic masses (endothelial cysts, epithelial cysts, parasitic cysts, and pseudocysts), solid masses (ganglioneuroma, ganglioneuroblastoma, extramedullary plasmacytoma (EMP), neurilemmoma, and lymphoma), fat-containing masses (myelolipoma, teratoma), and infectious masses (tuberculoma), and the imaging features of these uncommon masses are demonstrated. Although most of these lesions do not have specific imaging features, some fat-containing masses and cystic lesions present with characteristic appearances, such as myelolipoma, teratoma, and hydatid. Combination with histopathologic characteristic of these uncommon masses of adrenal gland, radiological features of these lesions on CT and MR imaging can be accurately understood with more confidences. Moreover, CT and MRI are highly accurate in localization of uncommon adrenal masses, and useful to guide surgical treatments.     

Gastrointestinal stromal tumors: CT and MRI findings

The objective of this study was to report the CT and MRI appearances of primary and metastatic gastrointestinal stromal tumor (GIST). The clinical and imaging findings of 31 patients with histological and immunohistochemical diagnosis of GIST were reviewed. The CT and MRI findings were assessed independently for size, location, enhancement characteristics, and pattern of metastatic disease. The tumors were of enteric (n=13), gastric (n=12), duodenal (n=2), and rectal (n=3) origin. In one case the primary site was the mesentery, without involvement of bowel. Primary tumors were typically exophytic (79%), larger than 5 cm (84%), and inhomogeneously enhancing (84%). Central necrosis of all tumors (37%) and aneurysmal dilation of enteric tumors (33%) were less common. Metastases were most commonly to mesentery (26%) or liver (32%). Less common findings were ascites (7%) and omental caking (3%). Liver metastases were hypervascular in 92% of patients and rapidly became cystic following therapy with imatinib mesylate (Gleevec; Novartis, East Hanover, NJ, USA). Lung metastases, bowel obstruction, vascular invasion, and significant lymphadenopathy were not seen in any patient. GISTs have some specific CT findings which could help differentiate them from other gastrointestinal tumors. Liver metastases became cystic following therapy, mimicking simple cysts. MRI was better than single-phase CT for assessing liver metastases, while CT was more sensitive for mesenteric metastases.     

CT of fibrous tissues and tumors with sonographic correlation

Fibrous tissues and tumors may appear hyperdense relative to muscles and solid viscera on CT both before and after IV contrast injection. In addition, fibrous tissues generally have a homogeneously hypoechoic sonographic appearance. The diagnostic value of these criteria is illustrated in a group of 21 fibrous tissue abnormalities that includes retroperitoneal, mediastinal, and perigraft fibrosis, sclerosing pseudotumor of the orbit, generalized fibromatosis, desmoids, malignant fibrous histiocytoma, and normal tendons and ligaments. It is concluded that while hyperdensity on CT and echopenia on sonography are not pathognomonic of fibrous tissue, they occur with sufficient frequency that their presence raises the possibility of a fibrous lesion.     

胚胎发育不良性神经上皮瘤的MRI表现与病理对照分析

目的:分析6例胚胎发育不良性神经上皮瘤(dysembryoplastic neuroepithelial tumors,DNT)的MRI表现和病理所见,探讨其MRI表现特征与病理间的关系。方法:回顾性分析6例经手术病理证实的DNT的MRI资料和病理所见,观察MRI信号改变与病理所见的关系。结果:典型的DNT位于皮层或主要位于皮层区,肿瘤以囊性成分为主,病灶在T1WI为低信号,T2WI为高信号,其ADC值增高,FLAIR序列上病灶边缘和分隔为高信号改变,增强扫描病灶实质结节或分隔可见轻度强化。瘤周无水肿,三角征和瘤内分隔为其影像学表现特征。与之病理对照所见DNT肿瘤细胞弥漫分布、密度不高、胞浆较空、存在黏液湖及肿瘤内富含薄璧分枝状血管是形成MRI所见的组织学基础。结论:DNT的MRI所见具有特征性,反映了其组织病理学改变特征,在病理诊断困难的情况下,结合临床和影像学表现,可以对DNT做出正确的诊断。     

Diagnosis and staging of laryngeal tumors with CT and MRI

Summary Cross-sectional imaging with CT and MRI plays an indispensable complementary role to endoscopy in the pretherapeutic workup and staging of laryngeal neoplasms. Adequate interpretation of the CT and MR images requires a thorough knowledge of the patterns of submucosal spread and familiarity with the diagnostic signs of neoplastic invasion as seen with each modality. In addition, the radiologist should be aware of the implications of imaging for staging and treatment. Both CT and MR imaging are highly sensitive for the detection of neoplastic invasion of the pre-epiglottic space, paraglottic space, subglottic region and cartilage. The high negative predictive value of both CT and MRI allows exclusion of neoplastic cartilage invasion quite reliably. The specificity of both CT and MRI is, however, limited and both methods may therefore overestimate the extent of tumor spread. Nevertheless, both cross-sectional imaging methods significantly improve the pretherapeutic staging accuracy of laryngeal tumors if used in addition to clinical examination and endoscopic biopsy. In the presence of a submucosal mass, CT and MRI play a key role for the diagnosis, as they may characterize the lesion, reliably depict its submucosal extent, and guide the endoscopist to perform deep biopsies that allow a definitive histological diagnosis.      

MRI and tumors of the mediastinum. Correlation with CT x-ray

This correlative study concerns the investigation of 22 mediastinal tumors by MRI and CT, subsequently verified by biopsies or surgery. It allows us to better define the technical aspects in the realization of MRI, including an assessment of the use of ECG gating. It also permits an appreciation of the respective performances of these 2 imaging methods: there is a good correlation between the two technics for both the positive and etiologic diagnosis of mediastinal tumors: in etiologic diagnosis, the same limitations were encountered with the two technics. However, MRI offers some advantages in the evaluation of tumoral extension. So, we suggest once a mediastinal mass has been shown using plain films, when available, MRI alone should be performed.     

Massive hepatic necrosis in the HELLP syndrome: CT correlation

We present a patient with toxemia of pregnancy and the HELLP syndrome [hemolysis (H), elevated liver enzymes (EL), and a low platelet count (LP)] resulting in massive hepatic necrosis. Cross-sectional imaging, including sonography, computed tomography, and nuclear medicine, was instrumental in the diagnosis and differentiation from hepatic abnormalities of other pregnancy related entities especially acute fatty liver of pregnancy.