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971.
A 45 year-old asymptomatic man was admitted to preoperative cardiovascular evaluation for noncardiac surgery. Physical examination and ECG were normal. Transthoracic echocardiography showed a 17 × 35 mm suspicious hyperechoic mass in the interventricular septum. Multi-slice computed tomograpy (MSCT) was used. Volume rendered image and an axial maximal intensity projection image demonstrated a mass with a density consistent with fat tissue ( − 78 HU). The MSCT findings were diagnostic of a benign lipoma. Thus, this mass was noninvasively diagnosed as cardiac lipoma. Neither life-threatening arrhythmia on Holter monitoring nor myocardial ischemia on exercise scintigraphy was observed. Transthoracic echocardiography is usually the initial diagnostic test in patients with a suspected cardiac mass. However, its sensitivity for differentiating tissue characteristics is limited. MSCT allow for detailed delineation of intra and pericardiac masses. In conclusion, we demonstrated the value of cardiac MSCT to diagnose an interventricular lipoma.  相似文献   
972.
We report two cases of renal amyloidosis associated with mesenteric and mediastinal Castleman disease of plasma cell type. Computed tomographic (CT) scan revealed a mesenteric mass with multiple nodal enlargement in one patient and a right paratracheal mass with irregular central calcifications in the second patient. Renal ultrasonography (US) showed increased echogenicity of the renal parenchyma with prominent medullas. Doppler waveform obtained in the kidney associated with mesenteric disease showed complete absence of diastolic flow signal, although it was normal in the patient with mediastinal disease. Recognition of Castleman disease as the cause of renal amyloidosis and the understanding of CT and US findings of this entity are important for the management, as well as its diagnosis.  相似文献   
973.
We report a case of liver metastasis of renal cell carcinoma with portal venous tumor thrombus. Abdominal computed tomographic images showed a large hepatic mass that enhanced slightly during arterial phase. Multiple hypoattenuating lesions were seen in the intrahepatic portal venous branches and were traced directly from the mass. The histologic specimen confirmed metastatic liver tumor of renal cell carcinoma with portal venous tumor thrombus.  相似文献   
974.
Background: We describe nonenhanced, early contrast-enhanced, and delayed contrast-enhanced computed tomographic (CT) features and contrast washout characteristics of lipid-poor and lipid-rich adrenal adenomas and nonadenomas to determine the role of these methods in distinguishing one type from the other.Methods: Sixty-five patients with 77 adrenal masses (16 lipid-poor and 37 lipid-rich adenomas and 24 nonadenomas) were consecutively examined with dynamic helical CT. Nonenhanced CT was followed by early enhanced CT at 5, 10, 15, and 30 min delays after administration of contrast material.Results: The difference between the mean nonenhanced and early contrast-enhanced values of the lipid-poor adenomas and nonadenomas was statistically significant, but the ranges of the values were overlapping. The lipid-poor adenomas had lower mean attenuation values than those of nonadenomas on delayed contrast-enhanced scans at each delay time, but these differences did not reach statistical significance. Even though the relative percentage washout of the lipid-poor adenomas was lower than that of lipid-rich adenomas, it was remarkably different from that of the nonadenomas.Conclusions: The absolute or relative percentage washout of contrast material on delayed contrast-enhanced CT is a highly specific test for the differentiation of lipid-poor and lipid-rich adrenal adenomas from adrenal nonadenomas.  相似文献   
975.
Background: We describe a retrospective analysis of the clinical presentation and imaging features in nine patients with adrenal histoplasmosis in nonimmunocompromised patients from a nonendemic region.Methods: Clinically, a tuberculosis-like presentation in four patients and a tumor-like presentation in five patients were seen. All patients were seronegative for the human immunodeficiency virus. Ultrasound (US) in all patients, computed tomography (CT) in six, and magnetic resonance imaging (MRI) in three showed suprarenal masses. CT-guided (in five) and US-guided (in four) biopsy and fine-needle aspiration cytology established a definite diagnosis. The work-up for malignancy and tuberculosis was negative.Results: On cross-sectional imaging, eight patients had bilateral adrenal masses and one had a unilateral adrenal mass. Imaging features were variable. All adrenal masses were hypoechoic on US, homogeneous in five, and heterogeneous in four patients. All adrenal masses were hypodense on CT, homogeneous in four, and heterogeneous in two. Heterogeneous enhancement was seen in three, homogeneous enhancement in two, and no enhancement in one patient. MRI in three patients showed that the masses were of variable signal intensity on all pulse sequences.Conclusion: Our case series showed that adrenal histoplasmosis does occur in immunocompetent persons living in areas not endemic for the disease. The imaging features were variable.  相似文献   
976.
Objectives: This systematic review and meta-analysis aimed to evaluate the diagnostic accuracy of contrast-enhanced computed tomography (CT) for varices in liver cirrhosis.

Methods: PubMed and EMBASE databases were searched for the literature identification. The area under the summary receiver operating characteristic curve (AUSROC), sensitivity, specificity, positive and negative likelihood ratio (PLR and NLR), and diagnostic odds ratio (DOR) were calculated. We performed the subgroup analyses according to the location of varices, CT technique, and study design. The study quality was assessed according to the QUADAS-2 tool.

Results: Seventeen papers were eligible. The study quality was modest. The AUSROC was 0.8975 and 0.9494 for predicting any size and high-risk varices, respectively. Summary sensitivity, specificity, PLR, NLR, and DOR of CT for predicting any size and high-risk varices were 0.87/0.80/3.67/0.18/22.70 and 0.87/0.88/7.52/0.12/65.55, respectively. According to the location of varices, the AUSROC was 0.9127 for predicting any size gastric varices alone; and the AUSROC was 0.8958 and 0.9461 for predicting any size and high-risk esophageal varices alone, respectively. According to the CT technique, the AUSROC of multi-detector CT (MDCT) was 0.9047 and 0.9490 for predicting any size and high-risk varices, respectively; and the AUSROC of MDCT esophagograms for predicting any size and high-risk varices was 0.8735 and 0.9664, respectively. In the subgroup analysis of prospective studies, the AUSROC was 0.9122 and 0.9507 for predicting any size and high-risk varices, respectively.

Conclusion: CT had a high accuracy for the diagnosis of varices in liver cirrhosis.  相似文献   

977.
978.
979.
Yang DH  Kim KW  Kim TK  Park SH  Kim SH  Kim MH  Lee SK  Kim AY  Kim PN  Ha HK  Lee MG 《Abdominal imaging》2006,31(1):94-102
Background Autoimmune pancreatitis is a new clinical entity that is characterized by peculiar histopathologic and laboratory findings and by a dramatic clinical response to corticosteroid therapy. We evaluated the radiologic findings of autoimmune pancreatitis. Methods Computed tomographic, magnetic resonance imaging, endoscopic retrograde cholangiopancreatographic, and ultrasonographic findings of 20 patients with autoimmune pancreatitis in our hospital between November 2000 and December 2003 were retrospectively reviewed regarding changes and ancillary findings in the pancreatic parenchyma, the main pancreatic duct, peripancreatic vessels, and distal common bile duct. In addition, follow-up images were reviewed for changes in any abnormality seen on the initial examinations. Results Pancreatic parenchymal enlargement was invariably seen that was diffuse (n = 19) or focal (n = 1), with homogeneous contrast enhancement on computed tomography (n = 20) and magnetic resonance imaging (n = 15). Capsule-like rim enhancement was seen in six patients. There was focal (n = 18) or diffuse (n = 2) narrowing of the main pancreatic duct and it was usually multifocal (n = 17) in the former. Narrowing of the peripancreatic veins was seen in 14 patients. There was tapered (n = 15) or abrupt (n = 3) narrowing of the distal common bile duct in 18 patients, with contrast enhancement of the narrowed segment in eight. Invariably, changes in the pancreatic parenchyma, main pancreatic duct, peripancreatic vessels, and common bile duct were normalized on follow-up studies after steroid therapy. Conclusion In this series, common radiologic findings of autoimmune pancreatitis were (a) diffuse pancreas enlargement, (b) multifocal narrowing of the main pancreatic duct, (c) narrowing of peripancreatic veins, and (d) tapered narrowing of the distal common bile duct with frequent contrast enhancement. These findings were usually reversible with steroid therapy.  相似文献   
980.
We present a 68-year-old male with left main coronary artery aneurysm and extensive coronary calcification involving the entire coronary arterial tree detected by coronary angiography and electron beam computerized tomography. With this article we also discussed the relationships between the pathogenesis of coronary atherosclerosis, coronary calcification, and coronary aneurysm formation.  相似文献   
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