CT and MRI of amyloidoma of the CNS

We present a case of cerebral amyloidoma in a 71-year-old woman. The clinical presentation and the radiological features were both highly suggestive for a brain tumor. Received 20 October 1995; Revision received 8 July 1996; Accepted 30 August 1996     

Soft-tissue amyloidoma of the extremities: a case report and review of literature

Amyloidosis is a heterogeneous group of disorders characterized by extracellular deposition of unique protein fibrils. Amyloidosis may be hereditary or acquired, and the deposits may be focal, localized, or systemic in distribution. The least common presentation of an amyloid deposition is as a discrete mass called amyloidoma or amyloid tumor. Although described at various body sites, soft-tissue amyloidoma in an extremity is exceedingly rare. We report such a case of a large amyloidoma in the thigh, which simulated a soft-tissue sarcoma. In spite of attaining a very large size over a course of more than 20 years, the clinical course and the histology of this lesion were benign. Awareness of this entity will allow this rare diagnosis to be considered, prevent confusion with malignant disease, and allow appropriate management and patient reassurance. A review of literature on soft-tissue amyloidomas of extremities is also being presented.     

Leiomyoma of the trachea: CT and MRI findings

A 47-year-old woman with a tracheal leiomyoma is described. Leiomyoma is a rare benign tumor of the trachea. Only 43 cases have been reported in the English- and Japanese-language literature. To our knowledge, this is the second time magnetic resonance imaging (MRI) findings have been reported. MRI can help discriminate between masses with a stalk and masses with a broad base, which in turn can help determine whether surgical resection of the tracheal leiomyoma is appropriate.     

Adrenal schwannoma: CT and MRI findings

We report a case of adrenal schwannoma, an extremely rare retroperitoneal neoplasm. The patient was a 33-year-old man who presented with an abdominal mass that was discovered at abdominal sonography. Computed tomography showed an 8-cm well-circumscribed homogeneous mass that enhanced slightly after intravenous administration of contrast material. Magnetic resonance imaging showed low signal intensity on T1-weighted images and heterogeneously high signal intensity on T2-weighted images. Although these imaging findings are nonspecific, adrenal schwannomas should be included in the differential diagnosis of solid nonfunctioning adrenal tumors.     

胸膜以外部位孤立性纤维瘤的CT和MRI影像分析

目的:探讨胸膜以外部位孤立性纤维瘤(ESFT)的CT和MRI表现及病理学特征,提高对本病的认识及诊断水平.方法:回顾性分析7例ESFT的CT和MRI表现度病理学表现.结果:本组ESFT的主要CT表现为略低密度软组织肿块.主要MRI表现为T1WI上肿瘤呈低信号～稍高信号,T2 WI上呈等信号或稍高信号.增强扫描示早期肿瘤...     

肺孤立结节的动态CT增强研究

目的：采用同层动态CT增强评价肺孤立性结节。方法：选择41例直径≤4cm的肺孤立性结节进行研究，其中肺癌29例，肺结核球7例，肺炎性结节3例，肺错构瘤2例。静注碘剂100ml前后，对病灶中心作薄层扫描，测量增强前后CT值。结果：肺癌和肺炎性结节显强化，肺结核球和肺错构瘤轻度强化或不强化，肺癌和肺结核在75s和135s时间段增强比较中均有统计学显性差异（P＜0.05)。结论：①动态CT增强对肺癌与肺结核球等结节的鉴别极有价值，并可将增强后CT净增值＜20HU，作为良恶性结节的阈值指标；②动态CT增强中应重视淋巴结的观察，有利于SPN的定性诊断。     

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.     

Primary lung carcinoma metastatic to a solitary fibrous tumor

We report the case of a 78-year-old man with a 2 month history of newly diagnosed metastatic lung adenocarcinoma, who presented with a left gluteal soft tissue mass. Histological examination of the mass revealed a solitary fibrous tumor containing metastases from adenocarcinoma.     

脑原发性淋巴瘤的CT、MRI诊断

目的:探讨脑原发性淋巴瘤的CT、MRI特征,以提高诊断水平。材料和方法:回顾性分析经病理证实的20例脑原发性淋巴瘤的CT和MRI表现。结果:20例共52个病灶,其中脑干4个、基底节14个、丘脑1个、胼胝体8个、枕叶10个、顶叶5个、颞叶5个、额叶4个、硬脑膜1个。位于脑深部近中线区域占78.8%;形态不规则(71.2%),内部发现囊变(15.4%),均未见钙化、出血。CT平扫均呈等或略高密度。T1WI呈低信号(30.7%)等信号(63.5%),T2WI等信号(69.3%),高信号(26.9%),增强后均呈显著增强。周围水肿(84.6%)。结论:脑原发性淋巴瘤的CT、MRI表现有一定特点,熟悉其临床及表现特点有助于对本病作出正确的诊断。     

Aspergillus infection of the respiratory tract after lung transplantation: chest radiographic and CT findings

The objective of our study was to assess radiographic and CT findings in lung transplant patients with evidence of Aspergillus colonization or infection of the airways and correlate the findings with clinical, laboratory, bronchoalveolar lavage, biopsy and autopsy findings. The records of 189 patients who had undergone lung transplantation were retrospectively reviewed for evidence of Aspergillus colonization or infection of the airways. Aspergillus was demonstrated by culture or microscopy of sputum or bronchoalveolar lavage fluid or histologically from lung biopsies or postmortem studies in 44 patients (23 %). Notes and radiographs were available for analysis in 30 patients. In 12 of the 30 patients (40 %) chest radiographs remained normal. In 11 of 18 patients with abnormal radiographs pulmonary abnormalities were attributed to invasive pulmonary aspergillosis (IPA) in the absence of other causes for pulmonary abnormalities (8 patients) or because of histological demonstration of IPA (3 patients). In these 11 patients initial radiographic abnormalities were focal areas of patchy consolidation (8 patients), ill-defined pulmonary nodules (2 patients) or a combination of both (1 patient). In some of the lesions cavitation was demonstrated subsequently. At CT a “halo” of decreased density was demonstrated in some of the nodules and lesion morphology and location were shown more precisely. Demonstration of Aspergillus from the respiratory tract after lung transplantation does not necessarily reflect IPA but may represent colonization of the airways or semi-invasive aspergillosis. The findings in patients with IPA did not differ from those described in the literature in other immunocompromised patients, suggesting that surgical disruption of lymphatic drainage and nervous supply or effects of preservation and transport of the transplant lung do not affect the radiographic appearances. Received 24 March 1997; Revision received 27 June 1997; Accepted 20 August 1997     

Intracranial hemorrhage: ultrasound, CT and MRI findings

Intracranial hemorrhage is one of the most common causes of acute focal neurologic deficit in children and adults. Neuroimaging including ultrasonography (US), computer tomography (CT) and magnetic resonance imaging (MRI) is essential in the diagnosis of intracranial hemorrhage. Imaging findings should guide treatment. The highly variable appearance of an intracranial hemorrhage can be challenging. A thorough knowledge of hematoma evolution and US, CT and MR hematoma characteristics is mandatory for adequate interpretation of findings. The purpose of this review is (1) to summarize the imaging characteristics of intracranial hemorrhage on various imaging techniques and (2) to review the various types of intracranial hemorrhage, and their causes.     

FDG avid solitary pulmonary nodule mimicking lung cancer

A healthy 49-year-old nonsmoker lady, who was found to have an incidental finding of a lung lesion on a chest X-ray. A Chest CT scan was performed and revealed left upper lobe, 1.5 cm solitary nodule with ground glass borders that highly suspicious for Bronchioloalveolar carcinoma and warranted further investigation to rule out malignancy. The FDG PET and/or CT scan was performed for staging and further evaluation and it displayed avidity of the nodule with a standardized uptake value (SUV) of 6.2, no abnormal uptake elsewhere in the body. CT guided biopsy was arranged and the histopathology result revealed eosinophilic pneumonia.     

Pulmonary manifestations of Hodgkin's disease: radiographic and CT findings

The aim of this study was to assess the radiological and CT findings in patients with pulmonary Hodgkin's disease and to analyse to what extent CT provides more diagnostic information. In 37 patients with 41 episodes of pulmonary manifestation of Hodgkin's disease (histological diagnosis: 11, clinical diagnosis: 30) 39 radiographs and 33 CT scans were analysed by two readers in consensus. Pulmonary nodules were recorded in 77% of radiographs (CXR) and 88% of CT scans. Nodules were multiple in 67% (CXR) and 86% (CT) and bilateral in 43% (CXR) and 66% (CT) of cases, respectively. Nodule size ranged from 2 to 100 mm. Of the nodules, 83% at radiography and CT, respectively, were < or =30 mm, and again 83% at radiography and CT, respectively, were irregularly marginated. Diffuse infiltration with and without nodules was less common. With pulmonary manifestations at initial diagnosis of Hodgkin's disease there was always hilar or mediastinal lymphadenopathy. Of 20 episodes, in which radiograph and CT had been obtained within 8 days, CT demonstrated pulmonary involvement when chest radiography was normal in 3 cases and demonstrated more lesions in 12 cases. The typical appearance of pulmonary HD consisted of multiple, irregularly marginated pulmonary nodules. Diffuse infiltration was less common. Computed tomography was superior to radiography not only in characterization of lesions but could also demonstrate pulmonary involvement when the radiograph was normal and should, therefore, be used liberally in addition to radiography.     

CT and MRI findings of mucin-containing tumors and pseudotumors of the thorax: pictorial review

Bronchial mucus has tomodensitometric features and MR signal intensity similar to that of water. However, chronic entrapped mucus collections, due to water reabsorption and higher protein content, can have CT attenuation values higher than 20 and reaching even 130 HU. Higher protein concentration also causes a sensible reduction in T1 relaxation time. The demonstration of mucus within a mediastinal, bronchial or pulmonary lesion is an important diagnostic clue permitting remarkable shortening of the list of differential diagnoses. This article illustrates the CT and MR findings allowing correct characterization of the mucus-containing lesions of mediastinum, bronchi, and lung.     

CT and MRI findings of cystadenofibromas of the ovary

The aim of this study was to assess imaging findings on CT or MR images of histologically proven ovarian cystadenofibromas. In the period 1995–2001, 32 histologically proven ovarian cystadenofibromas were identified in 28 women. Of the 32 ovarian cystadenofibromas, 16 tumors were purely cystic and the remaining 16 were complex cystic on CT or MR images. Solid components of 16 complex cystic tumors were seen as nodular (n=8) or trabecular (n=9) solid areas. One tumor had both nodular and trabecular solid components. Among 16 complex cystic tumors, 14 had thick or irregular septa; thus, half of ovarian cystadenofibromas had morphological imaging features of malignancy on CT or MR images. On histology, solid components in the cystic tumors were correlated with fibrous stromas that occasionally made a false-positive result for malignancy on imaging.     

CT and MRI findings in cerebral hydatid disease

Cerebal hydatid cysts account for 2% of all intracranial masses. Preoperative diagnosis is important since cyst rupture and spillage may cause an anaphylactic reaction. CT is the primary modality for the diagnosis. Two forms of cerebral hydatid cysts have been reported on the basis of CT appearances: unilocular and multilocular. Demostration of the cyst wall is important for the diagnosis. MRI is superior to CT for demostrating the cyst capsule and perifocal oedema. We retrospectively reviewed the CT and MRI findings of 6 surgically proven cases of cerebal hydatid cyst and compared the two modalities on the basis of their demonstration of findings helpful in the diagnosis, such as the capsule and perifocal oedema. In 1 case CT showed the capsule. In 2 cases MRI showed a hypointense capsule around the cyst on T2-weighted images. While CT is the modality of choice, in clinical practice MRI is superior for demonstrating the cys capsule, which is a helpful findings in the diagnosis and can be used in inconculsive cases. Correspondence to: U. Topal     

CT bronchus sign in malignant solitary pulmonary lesions: value in the prediction of cell type

The aim of this study was to evaluate differences in the prevalence of patterns of CT bronchus sign in malignant solitary pulmonary lesions (SPLs), according to their histologic cell types and with respect to size, location, and degree of cell differentiation. Computed tomography scans of 78 patients, in whom pathologically confirmed malignant SPLs with CT bronchus sign were present, were randomly selected and reviewed by two radiologists under consensus. All 78 were CT scans done using spiral technique with 10-mm collimation and 10-mm reconstruction intervals with enhancement, and 75 included additional high-resolution CT scans. Lesions were classified into four cell types as squamous cell carcinoma (n = 24), small cell carcinoma (n = 12), adenocarcinoma (n = 23), bronchioloalveolar carcinoma (BAC; n = 9), and others (n = 12), into three degrees of differentiation, into three size groups, and according to location (central or peripheral). Patterns of CT bronchus sign were classified into abruptly obstructing (I), patent (II), displacing (III), or tapered narrowing (IV) types. The relationships between the patterns of CT bronchus sign and cell type and degree of cell differentiation were evaluated. Eighty patterns of CT bronchus sign were observed in 78 patients. According to cell type, squamous cell carcinoma showed most often type-I pattern (45.8 %) but no type-II pattern, which was the most common pattern observed in BAC (77.8 %) and adenocarcinoma (34.8 %; p < 0.01). Small cell carcinoma showed a varied distribution among the four patterns of CT bronchus sign. According to location, in central squamous cell carcinomas, type-I pattern was more common(55 %; p < 0.01). Bronchioloalveolar carcinoma showed more peripheral lesions and in both central and peripheral lesions, type-II pattern was significantly more common (100 and 66.7 %; p < 0.01). In SPLs with CT bronchus sign of obstructing pattern, especially if central location, squamous cell carcinoma should be suspected, whereas in SPLs with patent CT bronchus sign, regardless of the location, the strong possibility of BAC should be considered. Received: 15 March 1999; Revised: 8 July 1999; Accepted: 28 December 1999     

Extensive lipomatosis of the small bowel and mesentery: CT and MRI findings

We report a patient with extensive lipomatosis involving both the ileum and mesentery. Axial computed tomographic images showed that diffuse and multiple intramural masses of fat densities compressed the ileum interior and abundant mesenteric fat compressed the retroperitoneum. Coronal magnetic resonance images showed thumbprinting of fluid containing ileum caused by fat-intensity masses.     

State-of-the-art CT and MRI of the adrenal gland

Both CT and MRI have achieved high accuracy in the investigation of patients suspected of having adrenal pathology. The choice of technique will depend on several factors discussed in the review. The advent of spiral CT has allowed the examination to be tailored to demonstrating the adrenal with very high spatial resolution and it remains the most widely used initial technique. This review concentrates on new techniques for evaluating the incidentally discovered adrenal mass and differentiating between adrenal adenomas and metastases. Received: 12 September 1996; Revision received 28 October 1996; Accepted 6 November 1996     

The pre-ossification center: normal CT and MRI findings in the trochlea

The pre-ossification center represents the initial structural change in the development of the secondary ossification center. We report CT and MRI findings of a focus in the cartilaginous trochlea of an appropriately aged child compatible with the pre-ossification center.