Thorotrast-induced hepatosplenic neoplasia: CT identification.

Despite discontinuation of its use in the 1950s, the consequences of Thorotrast usage continue to be recognized. In a review of plain film and CT findings of 20 cases of Thorotrast exposure, 15 of 17 patients demonstrated Thorotrast accumulation in the liver and spleen on plain films. Typically, this appeared as regions of trabeculated increased density within the liver. The spleen was of normal or decreased size and often demonstrated a finely punctate pattern of opacification. Only two malignancies could be suggested on plain film alone: one hepatic and one splenic. Five patients with hepatic malignancies underwent CT examinations: three with cholangiocarcinoma, one with angiosarcoma, and one with hepatocellular carcinoma. No specific criteria could be established to distinguish among these lesions, as each neoplasm appeared as relatively low-density mass(es). Two cases of splenic angiosarcoma appeared as low-density filling defect(s) in the otherwise opaque spleen, one case primary and the other metastatic from the liver. CT was superior to plain radiography in detecting and characterizing Thorotrast distribution and any superimposed malignancy. In addition to periodic liver function tests, screening CT of patients exposed to Thorotrast might detect hepatic neoplasms at an operable stage.

Ultrasonography and computed tomography in severe urinary tract infection.

A prospective study evaluated the utility of renal computed tomography (CT) and ultrasonography in 35 patients hospitalized for treatment of urinary tract infection. Renal computed tomograms were abnormal in 18 of 28 patients with acute pyelonephritis and three of four patients with urosepsis, showing findings consistent with pyelonephritis in 17 patients and intrarenal abscess or focal bacterial nephritis in four patients. Renal sonograms were abnormal in only eight patients, showing findings compatible with pyelonephritis in four and intrarenal abscess or focal bacterial nephritis in the other four. Flank tenderness was absent in only four patients with CT findings of pyelonephritis, of whom three were diabetic. We therefore found that (1) renal CT is a sensitive test for acute upper urinary tract infection, (2) ultrasonography detects focal bacterial nephritis and abscesses but is insensitive to uncomplicated upper urinary tract infection, and (3) painless pyelonephritis may be more common in patients with diabetes mellitus.

Renal oncocytoma: new observations.

Renal oncocytomas are uncommon, benign tumors that can be treated by local excision or heminephrectomy; their preoperative differentiation from renal cell carcinoma, treated by radical nephrectomy, would be invaluable. A particularly important finding, a central scar--not stressed in previous reports, is frequently demonstrated by CT examination. We evaluated radiographic studies of 18 pathologically confirmed cases of oncocytoma and compared findings with results of CT, sonography, and angiography studies of 18 renal cell carcinoma cases. Oncocytomas can be suggested if a stellate scar is identified within an otherwise homogenous tumor on ultrasound (US) and CT; if the mass appears homogeneous but no scar is present, angiography should be performed. An oncocytoma can be suggested in these cases if a spoke-wheel configuration and homogeneous blush are present. These criteria, which are reliable only if the mass is 3 cm or larger, would have resulted in the correct diagnosis of oncocytoma in 16/18 cases.

Transitional cell carcinoma of the kidney with invasion into the renal vein.

Eight cases of transitional cell carcinoma with extension into the renal vein are presented. In 2 cases the tumor had also invaded the inferior vena cava. Venous invasion represents an uncommon, late finding of transitional cell carcinoma and is associated with a poor prognosis. The excretory urogram usually demonstrates nonfunction or a pelvic mass with extensive renal invasion. As these findings are nonspecific, definitive preoperative diagnosis is dependent on direct visualization of the renal vein utilizing sonography, computed tomography, or venography. Since vascular invasion is a late finding, venous evaluation is required only in advanced cases of transitional cell carcinoma.

Hemorrhagic ascites: an unusual presentation of primary splenic lymphoma.

Hemorrhagic ascites is usually associated with a poor prognosis. A patient with hemorrhagic ascites having a potentially curable cause, primary splenic lymphoma (histiocytic type), is reported. It is believed that this is a new cause of hemorrhagic ascites that has not been previously described. The causes and pathogenesis of hemorrhagic ascites are reviewed. Computed tomography scan was helpful in suggesting the diagnosis and should be performed early in the evaluation of hemorrhagic ascites.

CT of benign cystic teratomas.

The computed tomographic (CT) findings in nine benign cystic teratomas are presented and compared with radiographic, sonographic, and pathologic data. CT rendered a specific diagnosis in six cases and was highly suggestive in two, with results superior to other imaging methods. In each instance, CT was successful in predicting or excluding invasion of adjacent structures, but was not reliable in predicting or excluding adherence to them. Specific CT characteristics of benign cystic teratomas are predominantly fatty mass with a denser dependent element and globular calcification, bone, or teeth in a solid protuberance into the cyst cavity. Suggestive patterns include fatty mass with rim calcification and water density mass with globular calcification and solid tissue elements. Illustrated for the first time are the CT appearances of the different calcifications seen in benign cystic teratomas.

Case report. CT diagnosis of splenic cystic lymphangiomatosis.

Several recent reports have stressed the role of angiography in the preoperative diagnosis of splenic cystic lymphangiomatosis. We describe a patient in whom computed tomography (CT) proved to be a key diagnostic tool that, when coupled with the radionuclide study, ultrasound, and clinical information, allowed for an accurate preoperative diagnosis. To our knowledge, there are no cases in the literature describing the use of CT in the evaluation of this entity.