Intraindividual comparison of gadoxetate disodium-enhanced MR imaging and 64-section multidetector CT in the Detection of hepatocellular carcinoma in patients with cirrhosis.

PURPOSE: To prospectively compare gadoxetate disodium-enhanced magnetic resonance (MR) imaging with multiphasic 64-section multidetector computed tomography (CT) in the detection of hepatocellular carcinoma (HCC) in patients with cirrhosis. MATERIALS AND METHODS: Institutional review board approval and informed patient consent were obtained for this prospective study. Fifty-eight patients (39 men, 19 women; mean age, 63 years; age range, 35-84 years) underwent gadoxetate disodium-enhanced MR imaging and multiphasic 64-section multidetector CT. The imaging examinations were performed within 30 days of each other. The two sets of images were qualitatively analyzed in random order by three independent readers in a blinded and retrospective fashion. Using strict diagnostic criteria for HCC, readers classified all detected lesions with use of a four-point confidence scale. The reference standard was a combination of pathologic proof, conclusive imaging findings, and substantial tumor growth at follow-up CT or MR imaging (range of follow-up, 90-370 days). The diagnostic accuracy, sensitivity, and positive predictive value were compared between the two image sets. Interreader variability was assessed. The accuracy of each imaging method was determined by using an adjusted modified chi(2) test. RESULTS: Eighty-seven HCCs (mean size +/- standard deviation, 1.8 cm +/- 1.5; range, 0.3-7.0 cm) were confirmed in 42 of the 58 patients. Regardless of lesion size, the average diagnostic accuracy and sensitivity for all readers were significantly greater with gadoxetate disodium-enhanced MR imaging (average diagnostic accuracy: 0.88, 95% confidence interval [CI]: 0.80, 0.97; average sensitivity: 0.85, 95% CI: 0.74, 0.96) than with multidetector CT (average diagnostic accuracy: 0.74, 95% CI: 0.65, 0.82; average sensitivity: 0.69, 95% CI: 0.59, 0.79) (P < .001 for each). No significant difference in positive predictive value was observed between the two image sets for each reader. Interreader agreement was good to excellent. CONCLUSION: Compared with multiphasic 64-section multidetector CT, gadoxetate disodium-enhanced MR imaging yields significantly higher diagnostic accuracy and sensitivity in the detection of HCC in patients with cirrhosis.

64-Section multi-detector row CT in the preoperative diagnosis of peritoneal carcinomatosis: correlation with histopathological findings.

BACKGROUND: To prospectively investigate the diagnostic accuracy of a 64-section multi-detector row computed tomography (CT) for the detection of peritoneal metastases, with the use of surgery and histopathological findings as the reference standard. METHODS: The study cohort comprised 18 patients with peritoneal carcinomatosis who underwent multiphasic CT with a 64-section CT, 0-119 days before cytoreductive surgery. Transverse CT images along with isotropic reformatted coronal and sagittal images were prospectively and independently evaluated by one of the five staff radiologists in an unblinded fashion. RESULTS: The overall sensitivity, specificity, positive, and negative predictive values of CT for the detection of peritoneal metastases were, respectively, 75% (93 of 124 lesions; confidence interval [CI] 68-84), 92% (118 of 128; CI 85-96), 90% (93 of 103; CI 83-95), and 79% (118 of 149; CI 72-86). For lesions 0.5 cm in diameter or larger, CT yielded a mean sensitivity of 89% (77 of 87; CI 75-97), although sensitivity decreased to only 43% (16 of 37; CI 28-56) for lesions <0.5 cm in diameter. CONCLUSIONS: 64-Section CT with the addition of isotropic reformatted coronal and sagittal images is a very effective technique in the detection of peritoneal metastases of 0.5 cm in diameter or larger, although sensitivity decreases remarkably for lesions <0.5 cm in diameter.

Adrenal lesions: spectrum of imaging findings with emphasis on multi-detector computed tomography and magnetic resonance imaging.

The adrenal gland is a common site of a large spectrum of abnormalities like primary tumors, hemorrhage, metastases, and enlargement of the gland from external hormonal stimulation. Most of these lesions represent nonfunctioning adrenal adenomas and thus warrant a conservative management. Multi-detector computed tomography (CT) and magnetic resonance (MR) imaging are still considered highly specific and complementary techniques for the detection and characterization of adrenal abnormalities. Radiologist can establish a definitive diagnosis for most adrenal masses (i.e., carcinoma, hemorrhage) based on imaging alone. Imaging therefore can differentiate malignant lesions from those benign and avoid unnecessary aggressive management of benign lesions. The article gives an overview of the adrenal lesions and their imaging characteristics seen on CT and MR imaging.