الفهرس 
Anatomy of the liver
• Computed tomography techniquesOnly 14 pages are availabe for public view
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Abstract
The role of imaging in patients with cirrhosis is to characterize the morphologic manifestations of the disease, evaluate the hepatic and extrahepatic vasculature, assess the effects of portal hypertension, and detect hepatic tumors, accurately differentiating HCC from other tumors. Both CT and MR provide valuable insights into the extent of hepatic injury from cirrhosis and complications including portal hypertension. Distinction among small hepatic focal lesions remains challenging, while both CT and MR are quite accurate in detection and characterization of larger (>2 cm) lesions, including hepatocellular carcinoma. Multiphasic contrast-enhanced helical computed tomography and magnetic resonance imaging have widely used as accurate screening modalities for patients with cirrhosis and suspected HCCs. The same set of parameters was assessed on the CT images from each patient and on the MR images from each patient. A liver volume index and a spleen volume index were calculated. These indices were not the true volumes of the organs; rather, they were values determined a standard way for comparison purposes. In addition to these parameters, each set of images was assessed for ascites, portosystemic collateral vessel formation, contour irregularities of the liver, and confluent fibrosis within the liver. All these findings were evaluated retrospectively from hard-copy images then they were used to compare with child pugh grades. In conclusion, both CT and MRI are important elements of the radiologic assessment of cirrhotic patients; however Contrast-enhanced spiral CT is generally superior to MRI for identifying vascular collaterals. This is because of the high spatial resolution of CT, and the ability to obtain very thin slices within a given volume also CT is the better for demonstrating confluent fibrosis. On the other hand MRI offers high intrinsic soft tissue contrast that help in detection of small focal lesions (<2cm) and detailed anatomic information owing to its multiplanar capabilities. In comparsion with child-pugh classification liver volume index on MRI and ascites on CT and MRI are good indicators of clinical severity of hepatic cirrhosis secondary to hepatitis. Although liver volume change is not one of the main parameters of Child-Pugh grading, it is correlated well with functional capacity of the liver in cases of cirrhosis secondary to viral hepatitis.