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Magnetic resonance (MR) images of the liver were used to study 43 patients with relatively small hepatocellular carcinomas (HCCs) and 36 with other hepatic mass lesions. In 27 HCC patients, histologic findings were available. All focal lesions detectable by CT without contrast media were delineated with greater contrast by MR imaging. The rate of detection depended on tumor size, being 97.5% for HCCs greater than 2 cm in the longest axis and 33.3% for those less than 2 cm. MR imaging demonstrated the ring sign characteristic of encapsulated HCC twice as frequently as CT scans. Inversion recovery (IR) images depicted the internal structure of the HCC better than T2-weighted spin-echo images. Lesions were classified into four patterns of intensity: low, iso, high, and mixed. The latter three were relatively characteristic of HCC and related closely with steatosis of cancer tissue. HCCs with fibrosis tended to have long T1 values; those with steatosis had short T1 values. T1 and T2 relaxation times were useful in the differential diagnosis.

Of 190 sets selective celiac and/or hepatic angiograms obtained in patients with hepatocellular carcinoma (HCC), comparison with gross anatomy of the liver was subsequently made by autopsy in 77 and by surgery in 23. It was found that the gross anatomy of HCC can be assessed with certain accuracy by careful interpretation of the angiograms, because tumor vasculature and vascular alterations in the noncancerous parenchyma are closely related to the mode of tumor growth, size of tumor nodules and their distribution. Even a fibrous capsule of the tumor may be discerned as a radiolucent zone around the tumor contour. Diagnosis of the gross anatomical type of HCC is important to the selection of therapeutic measure and assessment of prognosis.

An ultrasonic sector scanner and pulsed Doppler flowmeter were combined to measure portal venous velocity in 19 patients with portal hypertension and compared with cineangiographic mapping of a droplet of oil released into the portal vein. In 12 patients, measurements were made before and after pitressin [7] or ranitidine [5]. With the Doppler method, maximum basal portal venous velocity was 17.0 +/- 3.9 cm/sec., while average cineangiographic velocity was 8.5 +/- 2.7 cm/sec., a significant difference (p less than 0.001). After pitressin, velocity decreased to 8.3 +/- 2.7 cm/sec. with the Doppler method and 3.6 +/- 1.0 cm/sec. with cineangiography. Ranitidine did not produce an appreciable change. Doppler and cineangiographic velocity measurements exhibited significant correlation over a wide range of values (r = 0.960). Thus the pulsed Doppler method may give accurate values of portal venous velocity if they are corrected to cineangiographic values. Flow can be calculated from velocity and the cross-sectional area of the portal vein as measured on the sonogram. The Doppler method is simple and noninvasive and is particularly useful in studying changes in portal hemodynamics.

Tc-99m-phytate scanning of the liver and percutaneous transhepatic catheterization of the portal vein were performed in 33 patients--26 with cirrhosis, 3 with chronic active hepatitis, 2 with idiopathic portal hypertension, and 2 with unresolved acute hepatitis. A discrete defect in the porta hepatis area was seen in 6 of 28 patients who had portal vein pressure above 200 mm H2O. In 5 of the 6 patients with a false-positive scan, the umbilical portion of the left portal vein branch was dilated (larger than 25 x 20 mm) on the portogram, with or without a patent paraumbilical vein. The anatomical basis of this phenomenon is discussed, and it is suggested that this area be given special attention.

Selective left gastric venography was performed via percutaneous transheptic catheterization in 100 patients with portal hypertension to study hemodynamics and left gastric collaterals. Flow was hepatofugal in 81 patients, while 63 had varices supplied by the left gastric vein; azygos/hemiazygos collaterals were seen in 27 patients, gastrorenal shunts in 18, and other collaterals in 58. In 79 cases, enlarged, tortuous veins arising from thin parallel vessels at the esophagogastric junction on venography corresponded with varices on endoscopy in both size and course. Venography failed to show small varices which were seen endoscopically, whereas endoscopy often interpreted non-tortuous veins as varices. Using endoscopy as a reference, the sensitivity of venography for varices was 76%, specificity 100%, and accuracy 78%. There was a significant correlation between venographic demonstration of varices and previous hematemesis. Left gastric venography is necessary prior to embolization of varices and is also useful in their diagnosis as well as study of hemodynamics and assessment of bleeding risk.

The features on computed tomographic (CT) scans of nonalcoholic fatty liver were investigated in 24 patients with nonalcoholic fatty liver related to overweight. CT examinations were performed before and after 3 months of a low-calorie diet. The reversibility of fatty infiltration during diet therapy could be monitored by changes in appearance on repeated CT scans. Hepatic steatosis improved, as assessed from increases in attenuation values on CT scans after 3 months of the diet, and the improvement was accompanied by a decrease in the elevated serum glutamic-pyruvic transaminase activity. Hepatic fatty infiltration in these patients was not always uniform, and attenuation values in the right lobe of the liver were significantly lower than those in the left lobe. After the 3-month diet therapy, the mean liver volume was significantly reduced, while the spleen volume was unchanged. Two sequential CT examinations, performed before and after diet therapy, may be useful for evaluating obese patients with elevated serum transaminase activity.