Myung S. Shin

Computed Tomography of Primary Mediastinal Seminomas

Two cases of primary mediastinal seminoma presented as (a) aortic aneurysm with symptoms suggestive of coarctation of the aorta and (b) nonspecific tumor mass with left diaphragmatic paralysis. By computed tomographic (CT) scans both tumors were massive with sharply demarcated borders, loss of fat planes between the tumor and surrounding organs, and homogeneous density (30 to 40 Hounsfield units) only slightly enhanced by contrast medium infusion. Such CT findings should suggest the possibility of a primary mediastinal seminoma.

Clinical significance of azygos vein enlargement: Radiographic recognition and etiologic analysis

Azygos vein enlargement can be detected in congestive heart failure, portal hypertension, inferior vena cava thrombosis, right atrial mural thrombosis, a pulmonary embolism, congenital azygos continuation to the inferior vena cava, and the arteriovenous fistula. Radiography, particularly computed tomography (CT), is very useful, not only in recognition of azygos vein enlargement, but also in evaluation of its etiology for the institution of the appropriate treatment of the diseases.

Computed tomographic findings in suburothelial hemorrhage

Retroperitoneal hemorrhage with associated intramural hemorrhage into the renal pelvis and proximal ureter is a well documented complication of coagulation defects. The urographic characteristics of this condition have been well documented by several authors [1–4], but to our knowledge the computed tomographic (CT) findings in patients with this condition have not been reported previously. We describe the CT findings in 2 such cases; one related to thrombocytopenia in leukemia, and the other to anticoagulant therapy in a patient with Budd-Chiari syndrome.

Computed Tomographic Distinction of Submucosal Lipoma and Adenomatous Polyp of the Colon

Described here is a patient with 2 large pedunculated colonic tumors detected by barium enema radiography. By computed tomography (CT) 1 was found to be a submucosal lipoma characterized by oval shape, smooth demarcation, and homogeneous density with a CT number of −68 HU, whereas the other was an adenomatous polyp with slightly fuzzy outline and a much higher CT number. This case indicates that CT can be a definitive diagnostic modality for distinguishing between a colonie lipoma and other solid or cystic tumor of the colon.

CT diagnosis of false aneurysm of the pulmonary artery not demonstrated by angiography.

A 17-year-old patient with tricuspid atresia, palliatively corrected by a right Glenn and a left Potts anastomosis during his early childhood and a banding of the left pulmonary artery 6 years ago, developed a false aneurysm of the left pulmonary artery secondary to the erosion of the band fabric through the vascular wall with subsequent thrombosis, infection, and leakage. The diagnosis was confused by both chest roentgenography and angiography but was accurately made by postcontrast computed tomography (CT). We stress the importance and usefulness of CT in the diagnosis of a false aneurysm, not demonstrated by angiography.

Wegener's granulomatosis upper respiratory tract and pulmonary radiographic manifestations in 30 cases with pathogenetic consideration

Although the radiographic manifestations and pathologic features of Wegeners granulomatosis have been well described, their relationship to two variants of anti-neutrophil cytoplasmic antibodies (c- and p-ANCA) remains unclear. The purposes of this study are to analyze the radiographic and pathologic findings in 30 patients with Wegeners granulomatosis and to correlate c- and p-ANCA with such findings. Major histologic findings included parenchymal necrosis, necrotizing vasculitis, and granulomatous inflammations. Nodular lesions were more often associated with arteritis whereas patchy fluffy lesions associated with hemorrhagic capillaritis. ANCAs, particularly c-ANCA, instead of p-ANCA, were present in a high percentage of patients tested. These findings suggest that c-ANCA could play an important pathogenetic role in Wegeners granulomatosis which showed dual pathologic processes: vasculitis and granulomatous inflammation manifested radiographically as either nodular or pneumonia-like lesions, whereas p-ANCA was more often associated with patchy fluffy lung lesions as the consequence of hemorrhagic capillaritis.

Role of computed tomography in nonobstructive coarctation

Two cases of nonobstructive or pseudocoarctation of aorta evaluated by computed tomography are presented. Clinical features along with chest radiography and computed tomography findings provided specific information, making further workup by catheterization and angiography unnecessary. As most cases of nonobstructive coarctation are asymptomatic and require no treatment, its recognition is of great practical importance.

Localized saccular dilatation of the esophagus: an unusual cause of dysphagia.

Two young women who had undergone resection of an esophageal enteric cyst subsequently developed saccular dilatation of the esophagus. The abnormality was localized to the site of previous surgery and caused dysphagia in both patients.