Fibrosing mediastinitis

Fibrosing mediastinitis is a rare entity either idiopathic or caused by granulomatous disease. Plain film findings mainly show widening of the upper half of the anterior mediastinum, whereas CT delineates more clearly the exact location of the mediastinal mass and the extent of compromise of mediastinal structures. Although vessels surrounded by the fibrous mass are typically smoothly bordered and only rarely displaced, diagnosis can only be suspected together with the patients history and clinical course.     

Fibrosing mediastinitis.

Fibrosing mediastinitis is a rare benign disorder caused by proliferation of acellular collagen and fibrous tissue within the mediastinum. Although many cases are idiopathic, many (and perhaps most) cases in the United States are thought to be caused by an abnormal immunologic response to Histoplasma capsulatum infection. Affected patients are typically young and present with signs and symptoms of obstruction or compression of the superior vena cava, pulmonary veins or arteries, central airways, or esophagus. There may be two types of fibrosing mediastinitis: focal and diffuse. The focal type usually manifests on computed tomographic (CT) or magnetic resonance (MR) images as a localized, calcified mass in the paratracheal or subcarinal regions of the mediastinum or in the pulmonary hila. The diffuse type manifests on CT or MR images as a diffusely infiltrating, often noncalcified mass that affects multiple mediastinal compartments. CT and MR imaging play a vital role in the diagnosis and management of fibrosing mediastinitis.     

Elastofibroma: CT and MR findings

Two cases of elastofibroma of the chest wall are reported. Each patient was investigated with CT and, in 1 case, MR imaging was also performed. Elastofibroma appears like a mass in the subscapular region and often presents problems of differential diagnosis. The contribution of MR imaging is reported.     

Lead encephalopathy: CT and MR findings

Lead is toxic to many organ systems, among them bone marrow, muscles, kidneys, endocrine glands, joints, and nervous system. Encephalopathy is a rare but severe complication of lead poisoning. Lead toxicity is much less common in adults. Adult lead poisoning results primarily from exposure by inhalation in the workplace. In this report, two cases of adult toxic encephalopathy due to lead poisoning are presented with CT and MR findings.     

Marchiafava-Bignami disease: CT and MR findings

We describe characteristic findings in a patient with Marchiafava-Bignami disease who was serially imaged with CT and MR. Involvement of the entire corpus callosum was visualized with both types of imaging. Following administration of gadolinium-DTPA, the lesion was clearly enhanced in the subacute stage. Correspondence to: S. Otake     

Meningioangiomatosis: CT and MR findings.

Meningioangiomatosis (MA) is a rare hamartomatous lesion of the cerebral cortex; to date only 18 cases with imaging findings have been reported in the English literature. The origin of MA is probably malformative, with possible association with neurofibromatosis. These lesions frequently cause seizures in young patients. We report two new cases seen at our institution and present their CT and MR findings clearly illustrating MA cortex infiltration. Gd-DTPA used in one of the two cases failed to cause enhancement.     

Duodenal diverticulitis: CT and MR findings

We report a case of duodenal diverticulitis and describe the helical computed tomography and contrast-enhanced magnetic resonance imaging (MRI) study findings. Due to its uncommon appearance, this lesion is not typically included in the differential diagnosis of pancreatitis or cholecystitis. The imaging findings of duodenal diverticulitis can be very suggestive of its diagnosis or can narrow the differential diagnosis. To our knowledge and in spite of the wide use of MRI, the contrast-enhanced MRI features of this entity, as described below, have not yet been reported in the literature.     

Nasopharyngeal teratoma: CT and MR findings

Teratomas of the nasopharynx occur usually in neonates. We present a case of teratoma which was discovered in an adult, and which relapsed after 34 years. The conventional radiograms, CT, MR, and histologic appearances are described. Received 3 January 1996; Revision received 1 March 1996; Accepted 4 March 1996     

Struma ovarii: CT and MR findings

A case of pure struma ovarii is reported with its CT, magnetic resonance (MR), and pathologic findings. Both MR and CT revealed a complex mass composed of solid elements and multiple cysts; CT revealed calcifications not apparent on MR.     

Intracranial hemangioblastomas: CT and MR findings

The CT and magnetic resonance (MR) findings in eight patients with 10 biopsy-proven intracranial hemangioblastomas were reviewed. Three of these patients had von Hippel-Lindau (VHL) syndrome. Nine tumors were infratentorial, seven were cystic, and five had well-defined mural nodules. The only three solid tumors, the only brain stem tumor, and the only supratentorial tumor in this series occurred in VHL patients. Magnetic resonance detected a single tumor missed by CT, and no lesion seen on CT was missed by MR. The tumor nodule, when present, was identified in every case using MR, although it was usually more apparent on contrast-enhanced CT. In three cases MR was better than CT in defining the margins of posterior fossa tumors. Serpentine vessels were well seen as flow voids against high signal cyst or tumor on T2-weighted images, but contrast-enhanced CT also demonstrated them. Magnetic resonance was found superior to CT for the detection of intracranial hemangioblastomas, and complementary in their characterization.     

Meningovascular syphilis: CT and MR findings

The radiologic findings in three cases of meningovascular syphilis are presented. Angiography demonstrated varying degrees of narrowing and ectasia of the supraclinoid carotid, basilar, and proximal anterior and middle cerebral arteries, as well as distal branches. Computed tomography (CT) showed multifocal infarction with variable enhancement. Similarly, in the one case studied with magnetic resonance (MR), several regions of high signal intensity on T2-weighted sequences were found, which were compatible with foci of ischemia. Although the radiologic findings are nonspecific, the diagnosis of meningovascular syphilis should be considered in patients with vasculitis of uncertain etiology.     

Macrodystrophia lipomatosa: CT and MR findings

Macrodystrophia lipomatosa is a congenital macrodactyly characterized by proliferation of all mesenchymal components, particularly fibroadipose tissue. We report imaging features of two such patients. MR imaging and CT scanning demonstrated proliferation of fatty tissue in the territory of the median nerve in the hands and forearms, characteristic of macrodystrophia lipomatosa.     

Hyperostotic esthesioneuroblastoma: CT and MR findings

Olfactory neuroblastoma is a malignant, slow growing, neurogenic tumor that originates in the olfactory mucosa of the upper nasal cavity. Its CT appearance, i.e., a soft tissue mass adherent to the cribriform plate usually with bone lysis, has been described. Two cases are presented in which this entity was associated with exuberant bony hyperostosis, a feature not previously reported. The differential diagnosis of nasoethmoid soft tissue masses with associated hyperostosis is reviewed.     

Lhermitte-Duclos disease: CT and MR findings

The typical CT findings of Lhermitte-Duclos disease (dysplastic gangliocytoma of the cerebellum) are a hypodense nonenhancing unilateral posterior fossa mass, with or without adjacent occipital thinning, hydrocephalus, and calcification. Magnetic resonance (MR) has been found to be very helpful, and superior to CT, in delineating the margins of the lesion for determining the extent of surgical resection. Since recurrence is known, MR is important in the follow-up of these patients. To our knowledge this is the first reported case that included MR examination with administration of gadolinium. There was no enhancement of the lesion, consistent with previous reports of no contrast enhancement on CT.     

Sinus pericranii: CT and MR findings

A case of sinus pericranii communicating with the right transverse sinus is reported. The radiographic findings on CT, angiography, and magnetic resonance imaging are presented.