Giant cranial hemangiopericytoma: MR and angiographic findings.

The authors detail the MR and angiographic findings of a very large hemangiopericytoma in the skull of a 63-year-old woman. Angiography showed a marked tumor blush with early draining veins; MR showed heterogeneously increased T2 signal intensity and enhancement with gadolinium secondary to the richly vascularized tumor.

Rare pulmonary manifestation of Ehlers-Danlos syndrome.

Ehlers-Danlos syndrome (EDS) is an inherited disorder of connective tissue with multiple thoracic manifestations. We present an unusual thoracic manifestation of EDS consisting of parenchymal cysts and fibrous and fibroosseous nodules. These manifestations may be related to an abnormal attempt at repair of parenchymal or vascular tears.

Chest manifestations of AIDS.

Chest radiographs, computed tomography and gallium scanning are useful in diagnosing the pulmonary manifestations of acquired immunodeficiency syndrome. Most opportunistic infections in patients with AIDS affect the lung as the primary target organ. Bilateral perihilar or basilar interstitial infiltrates, which may progress to the ground-glass appearance of adult respiratory distress syndrome, are commonly seen in cases of Pneumocystis carinii pneumonia. Unilateral or miliary infiltrates and cavitary lesions may be atypical presentations. Diffuse interstitial infiltrates are also seen in mycobacterial, fungal and cytomegalovirus infections. Mycobacterium tuberculosis infection in AIDS patients resembles primary tuberculosis infection rather than secondary tuberculosis reactivation. Intrathoracic adenopathy in AIDS patients suggests neoplastic processes, such as lymphoma and Kaposi's sarcoma, and opportunistic infections such as M. tuberculosis, Mycobacterium avium-intracellulare and fungal infections. Bronchoscopy with bronchoalveolar lavage and transbronchial biopsy are usually necessary for identification of the etiologic agent.

Malignant tumors of the heart and great vessels: MR imaging appearance.

Fortunately, primary tumors of the heart and great vessels are rare. These primary tumors include angiosarcoma, malignant fibrous histiocytoma, high-grade and pleomorphic sarcoma, and paraganglioma with pericardial and myocardial invasion. Symptoms are often nonspecific and include chest pain and dyspnea. Although these tumors are often diagnosed with echocardiography and computed tomography, magnetic resonance (MR) imaging currently appears to be the imaging modality of choice because of its diverse capabilities, which include multiplanar imaging for excellent anatomic definition of the heart, pericardium, mediastinum, and lungs; improved morphologic differentiation between tumor tissue and surrounding cardiovascular, mediastinal, or pulmonary tissues; dynamic imaging with a gated cine-loop acquisition; and assessment of tissue perfusion. The use of gadopentetate dimeglumine is helpful in achieving tumor enhancement on MR images but is not required. MR imaging is also useful in assessing tumor response to surgery, radiation therapy, and chemotherapy.

Sclerosing lobular hyperplasia of the breast: imaging features in 15 cases.

OBJECTIVE: Sclerosing lobular hyperplasia is an infrequent benign lesion of the breast, defined as prominent hyperplasia of the lobules with sclerosis of the interlobular stroma. It commonly presents as a tumorlike mass clinically. Sclerosing lobular hyperplasia has been identified at biopsy at our institution with rare but increasing frequency. We reviewed the imaging features of 15 patients with biopsy-proven sclerosing lobular hyperplasia to determine if a characteristic imaging pattern could suggest this diagnosis. MATERIALS AND METHODS: The mammograms and sonograms of all women with pathologically proved sclerosing lobular hyperplasia seen between January 1986 and June 1993 were retrospectively reviewed by two of the authors who were familiar with the pathologic diagnosis. Imaging findings that led to biopsy or were present on the preoperative studies were reviewed. The study included 15 patients ranging in age from 21 to 46 years old, with a mean age of 32 years. Seven were black, and eight were white. All women had mammograms, three patients had prior mammograms for comparison, and sonography was done in all but one case. Presenting symptoms included a recently discovered breast lump in eight patients, breast tenderness in one patient, and a clear nipple discharge in one patient. The other five were asymptomatic and had screening mammograms. RESULTS: Eight patients (53%) had a well-defined mass on mammography, varying in size from 1.0 cm to 8.0 cm (mean, 3.7 cm). In one of these patients, the nodule was proved to be a fibroadenoma; sclerosing lobular hyperplasia was found only microscopically. Microcalcifications were present within the mass on mammography in one patient. Mammograms in two women showed asymmetric increased density compared with the opposite breast, and in five cases, the mammographic findings were interpreted as normal. Sonograms showed a solid, well-defined mass with either homogeneous or mixed echoes in 10 of 14 patients (71%). In only one of these nodules was acoustic enhancement present. In the other four women, sonograms were normal. No characteristic findings were identified that would suggest sclerosing lobular hyperplasia as a likely diagnosis preoperatively, and, in fact, in many cases a diagnosis of fibroadenoma was considered most probable. CONCLUSION: The imaging findings of sclerosing lobular hyperplasia are not sufficiently characteristic to distinguish the lesion from fibroadenomas and well-circumscribed carcinomas.

Unusual artifact with mammography film.

The authors identified the origin of a high-density artifact with mammography film. An acrylic ramp phantom (thickness, 0-7 cm) was used to create a continuously variable radiation exposure. A perturbation in the curve of optical density versus position along the ramp was observed. Development of the film with the emulsion side down eliminated this artifact.

Bone marrow reconversion in adults who are smokers: MR Imaging findings.

OBJECTIVE: Conversion of bone marrow in the extremities from red to yellow is a normal maturation process. Marrow reconversion is present when expected yellow marrow is replaced with active red marrow, and it tends to occur at times of physiologic stress. The significance of this finding on MR imaging is not always clear. Accordingly, we studied the prevalence of bone marrow reconversion in adults undergoing MR imaging of the knee for reasons other than marrow disorders. Possible relationships between marrow reconversion and age, sex, weight, and smoking were sought. MATERIALS AND METHODS: Fifty-nine outpatients over 24 years of age who had no evidence of hematopoietic disorders and for whom MR images of the knee were available for review were selected for study. Patients younger than 25 years old were eliminated to ensure that all patients in the study were old enough to have achieved normal adult marrow conversion. The 59 subjects were classified according to their smoking histories. Twenty-eight were nonsmokers, 10 were intermediate smokers, and 21 were heavy smokers. The MR images were classified as showing either red marrow (reconverted from yellow to red) or yellow marrow (converted) by two independent observers who had no knowledge of the patients' smoking histories. RESULTS: MR images of six heavy smokers, two intermediate smokers, and one nonsmoker showed evidence of reconversion. A statistically significant association between marrow reconversion and heavy smoking (p = .02) was found. Reconversion also was found to be more prevalent in patients less than 39 years old and in obese women who smoked. No association was found between weight, sex, or obese male smokers and reconversion. CONCLUSION: Our results show marrow reconversion at the knee is most prevalent in heavy smokers, younger patients, and especially obese women who smoke heavily. In these patients, marrow reconversion can be a normal finding on MR imaging. In other patients, other causes should be considered.