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PURPOSE: To determine whether adrenal adenomas can be differentiated from metastases on fat-saturated magnetic resonance (MR) images. MATERIALS AND METHODS: Twenty-eight adrenal adenomas and 20 metastatic lesions were imaged at 1.5 T by means of fat-saturated T1- and T2-weighted and gadolinium-enhanced T1-weighted sequences. The authors evaluated visually whether structures of high signal intensity (hyperintense rim sign) could be observed in the outer margin of the adrenal masses. RESULTS: Twenty-six of 28 adrenal adenomas revealed the hyperintense rim sign on at least one kind of fat-saturated image, compared with only one of 20 metastases. The sensitivity of the hyperintense rim sign as suggestive of adrenal adenoma was 92%, specificity was 95%, and overall accuracy was 94%. CONCLUSION: The hyperintense rim sign is characteristic of adrenal adenomas. Thus, adrenal adenomas can be differentiated from metastases by means of this new imaging sign on fat-saturated MR images.

This study evaluated the usefulness of dynamic MRI to differentiate various adrenal tumours.Sixty-five adrenal tumours (28 adenomas, 22 metastases, seven phaeochromocytomas, five neurogenic tumours and three tuberculous granulomas) were evaluated with gadolinium-enhanced dynamic MRI (13 at 0.5 T, 52 at 1.5 T). In this technique, a series of 12 sequential images (gradient-echo images at 0.5 T and spin-echo images at 1.5 T) were obtained up to 21 min after bolus administration of 0.1 mmol/kg Gd-DTPA.All 28 adenomas showed peak enhancement in the early phase (2 min) and quick washout. Fourteen of 22 metastases showed peak enhancement in the early or middle phase (9 min) and slow washout. Six of seven phaeochromocytomas revealed marked peak enhancement in the early phase and little washout. All neurogenic tumours showed gradually increasing enhancement. Granulomas showed little enhancement. As a result, only 14 adrenal masses (27/65, 42%) were correctly classified according to contrast enhancement patterns. However, if we consider each type of enhancement pattern to be specific to adenoma, metastasis, phaeochromocytoma, neurogenic tumour and tuberculous granuloma respectively, 56 of the 65 adrenal masses (86%) could be classified. Seven of the indistinguishable nine tumours were performed at 0.5 T system using gradient-echo sequences.Dynamic MR imaging at 1.5 T is useful in the differentiation of adrenal masses. Imaging at 0.5 T with gradient-echo sequences seems less useful to distinguish adenomas from metastases.

PURPOSE: To determine whether decreased signal intensity of the motor cortex (T2 shortening) at magnetic resonance (MR) imaging is a useful finding for supporting the diagnosis of amyotrophic lateral sclerosis (ALS). MATERIALS AND METHODS: High-field-strength (1.5-T) MR images of 15 patients (seven men and eight women, aged 28-80 years) and 49 neurologically normal age-matched control patients were examined for T2 shortening in the motor cortex. In addition, brains of patients with ALS were examined at autopsy. RESULTS: The MR images of 14 of the 15 patients showed T2 shortening in precentral cortices, while the images of all but one of the control patients showed no such finding. In three of eight brains at autopsy, sections from the precentral cortex showed sparsely distributed, intensely stained astrocytes and macrophages. CONCLUSION: Abnormal iron deposition associated with the degenerative process could be the source of T2 shortening, which is a useful MR imaging finding in the diagnosis of ALS.

We reviewed the CT examinations of 17 patients who had hepatic schistosomiasis japonica and noted peculiar hepatic calcifications in 15 cases and a notch on the hepatic surface in six. A hepatocellular carcinoma was found in six patients. The calcifications and notch appeared to indicate the degree of hepatic fibrosis but did not correlate with cirrhotic deformation.

Out of 79 consecutive cases of hepatocellular carcinoma (HCC) examined with computed tomography (CT), five patients revealed metastatic swollen abdominal lymph nodes. Involved were portal, retropancreatic, common hepatic, superior mesenteric, and paraaortic nodes. CT appeared to be an excellent modality in the diagnosis of metastatic abdominal lymph nodes of HCC.

Obstruction of the inferior vena cava (IVC) occurs in any segment, but more commonly in the infrarenal and diaphragmatic segments. However, occlusion in both segments has rarely been encountered. We have successfully opacified the intervening segment between two occluded segments, confirmed its patency and clarified its detailed anatomy by percutaneous transhepatic inferior vena cavography (PTIVC) in a patient. A 52-year-old man presented with repeated episodes of thrombophlebitis in his lower extremities and prominent subcutaneous varices of the trunk. Laboratory data disclosed impaired hepatic and normal renal function: total serum bilirubin 2.9 mg/dl, direct bilirubin 1.6 mg/dl, alkaline phosphatase 465 IU/l, leucine aminopeptidase 125 IU/l, γ-glutamyl transpeptidase 293 IU/l, glutamate oxaloacetate transaminase 43 IU/l, glutamic pyruvic transaminase 26 IU/l, urea nitrogen 15 mg/dl and creatinine 0.5 mg/dl.

An accessory lateral segmental branch of the protal vein was found in a patient with esophageal varices. This rare anomalous branch should not be mistaken for a coronary vein supplying varices.

Twenty-seven consecutive cases with a prospective diagnosis of cancer of the gallbladder were analyzed to clarify the computed tomographic (CT) and ultrasonographic features, behavior, and prognosis of intraluminal papillary carcinoma (n = 7) of the organ. With CT and ultrasonography, these intraluminal carcinomas were further classified into 3 subtypes: single polyp, multiple polyp, and jam-packed gallbladder. Preoperative diagnosis, evaluation of local invasiveness, and detection of metastatic lesions were reliably done. Carcinomas of this type were locally less invasive, less frequently metastasized, and resulted in a longer survival than the other massive and thickened-wall carcinomas.