Evaluation of histologic subtype and degree of differentiation in hepatocellular carcinoma (HCC) is essential because it affects patient prognosis and treatment planning. To evaluate the histologic subtype of HCC with magnetic resonance (MR) imaging, conventional spin-echo and dynamic studies were correlated with histopathologic and angiographic findings in 72 HCCs. Dynamic MR imaging was performed with the fast low-angle shot (FLASH) technique after administration of gadopentetate dimeglumine. There was considerable overlap in signal intensity between various tumor grades on both T1- and T2-weighted images. On dynamic MR images, the peak contrast enhancement ratio correlated with tumor grade (well-differentiated, 29.5 +/- 24.7; moderately differentiated, 63.5 +/- 24.1; poorly differentiated, 86.9 +/- 26.4) or degree of dilatation of the sinusoidlike vascular space between tumor cells. The maximum contrast-to-noise ratio in tumor (relative to surrounding liver) was achieved within 60 seconds in 45 HCCs (mostly of the trabecular or pseudoglandular type). Enhancement was slight or minimal in 17 tumors (mostly small, well-differentiated tumors). In 10 tumors, the degree of enhancement increased with time, with maximum enhancement in the delayed phase (most frequently in scirrhous HCC). These dynamic patterns correlated with angiographic findings. These data indicate that the degree and pattern of enhancement on dynamic MR images reflect tumor differentiation and architecture of HCC.

Angiography, Digital Subtraction↗

PubMedDate not supplied

MR imaging enhancement with superparamagnetic iron oxide in chronic liver disease: influence of liver dysfunction and parenchymal pathology.

PURPOSE: To analyze the influence of liver dysfunction and parenchymal pathology on the accumulation of superparamagnetic iron oxide (SPIO). METHODS: We evaluated MR images of 13 patients having small hepatic neoplasms before and after administration of SPIO (10 micronol/kg). Biopsy and laboratory data confirmed the presence of severe cirrhosis in two patients, mild cirrhosis in four, chronic hepatitis in five, and normal livers in two. Degrees of liver dysfunction or liver parenchymal pathology were correlated with reductions in signal intensity of the liver and spleen after administration of SPIO. Signal intensity reduction was evaluated using a 1.5 Tesla MR unit. RESULTS: Response to SPIO of the liver and spleen did not correlate with liver parenchymal pathology, although reductions in signal intensity of the liver were somewhat small in severely cirrhotic livers. There were slight correlations between signal intensity alterations of the liver and laboratory data such as the indocyanine green retention rate (correlation coefficient 0. 47), albumin (0.36), total bilirubin (0.36), and serum glutamic oxaloacetic transaminase (GOT) (0.46). Signal intensity reduction of spleen did not correlate with liver function tests except for serum GOT. In patients with cirrhosis, heterogeneous structures were detected in the nontumorous portions of the liver. However, these did not prevent the diagnosis of small hepatomas. CONCLUSION: The uptake of SPIO showed some correlation with liver function but not with chronic liver parenchymal pathology. SPIO provided sufficient contrast between tumor and surrounding liver parenchyma among patients with chronic liver disease.

Adult↗

PubMedDate not supplied

Dynamic MR imaging of hepatic adenomas with pathologic correlation.

Two patients with hepatic adenomas (HAs) were evaluated using dynamic magnetic resonance (MR) imaging. Findings of conventional MR imaging of HAs have varied according to reports in the literature, and dynamic MR imaging of HAs has not been previously reported. Dynamic MR imaging using Gd-DTPA showed homogeneous enhancement in the early dynamic phase and prolonged enhancement in the late phase in the typical HA of Case 2. The HA of Case 1 contained fibrosis and exhibited delayed enhancement. The opacification of contrast enhancement was homogeneous and did not occur from the peripheral region as is observed in typical hemangiomas. In addition, washout of contrast material was not as rapid as with typical hepatocellular carcinomas (HCCs).

Adenoma, Liver Cell↗

PubMedDate not supplied

Renal cell carcinomas in von Hippel-Lindau disease; tumor detection and management.

Twenty-seven renal cell carcinomas (RCCs) found in one family affected with von Hippel-Lindau disease were examined using ultrasound (US), CT, MRI and angiography. The sensitivity of the tumor detection using different imaging modalities was evaluated by macroscopic pathology (solid or cystic) and size (exceeding 2cm in diameter or not). In 18 of the RCC's exceeding 2cm in diameter (eight solid and ten cystic), all lesions were detected on US, CT, and MRI. However, on angiography, solid RCCs were detected in 88%, and cystic RCCs were detected in 60%. In nine RCCs less than 2cm in diameter (seven solid and two cystic), solid RCCs were detected in 86% on US, 86% on CT, 80% on MRI, and 43% on angiography, but cystic RCCs were detected in 50% on only CT and MRI. From the pathologic correlation, even renal simple cystic lesions in VHL are considered premalignant lesions and they had better be removed if the residual renal function after surgery is preserved. In case of the observation, they should be followed carefully using thin slice thickness dynamic CT to discover the wall irregularity, septation and irregular contour.

Adult↗