الفهرس 
liver anatomy and hestologyOnly 14 pages are availabe for public view
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Abstract
Most chronic liver diseases (CLDs) can lead to liver fibrosis & eventually cirrhosis. Over many years the principle causes of CLD have been chronic viral hepatitis B (CHB), chronic viral hepatitis C and alcoholic liver disease (ALD). While rates of alcoholism and ALD are falling in many countries, hazardous drinking amongst young people is resulting in alarming rates of ALD in several northern European countries; other aetiologies of chronic liver diseases include parasitic infestations (e.g schistosomiasis), autoimmune hepatitis, neonatal liver diseases, metabolic disorders, drug toxicity besides non alcoholic steatohepatitis (NASH). Liver fibrosis is an excessive accumulation of extracellular matrix proteins which is the result of all chronic liver disease. The main source of extra- cellular matrix proteins is an activated hepatic stellate cells, which are resident perisinusoidal cells in the subendothelial space between hepatocytes and sinusoidal endothelial cells and the primary site for storing retinoids (vitamin A). Patients with cirrhosis may present in a variety of ways and with varied clinical findings. The history and physical examination can provide clues to the presence of cirrhosis and suggest an etiology. Many patients may present with complications e.g liver cell failure (ascites, bleeding tendancies, and portal hypertension with esophageal varices) and /or hepatocellular carcinoma. Diagnosis of liver diseases can be achieved through one or both of two methods: noninvasive methods that include both laboratory diagnosis (routine and novel serum biomarkers) and diagnostic imaging. On the other hand, invasive diagnosis is done through histopathological examination of liver tissue by liver biopsy. from class II biomarkers, Aspartate aminotransferase to alanine aminotransferase (AST/ALT ratio) has been proposed as indirect marker of hepatic fibrosis, with values > 1 being suggestive of cirrhosis with high diagnostic accuracy. But some study shows the diagnostic accuracy to be clearly inferior to that of other indirect fibrosis tests based on routine laboratory parameters. Another test is the Fibrotest, the most widely known, and the most validated of the tests for the noninvasive evaluation of liver fibrosis. FibroTest and ActiTest has the ability to identify the presence of fibrosis and necroinflammatory activity in patients with hepatitis C. A cut-off of activity index at 0.30 had 90% sensitivity and 88% positive predictive value for the diagnosis of bridging fibrosis or moderate necroinflammatory activity. Conventional methods (US, CT and MRI) that can suggest the presence of cirrhosis. Computed tomography and MRI are well suited to demonstrate volume loss of the right hepatic lobe and the medial segment of the left hepatic lobe with compensatory enlargement of the remainder of the left lobe and the caudate lobe because both the right lobe and the caudate lobe are clearly seen. The major utility of these modalities in the evaluation of patients with cirrhosis is in its ability to detect complications of cirrhosis such as ascites, hepatocellular carcinoma, and hepatic or portal vein thrombosis. Conclusion: So, the liver biopsy is considered up to this date the gold standard for the diagnosis of liver fibrosis, cirrhosis caused by chronic liver diseases.