الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 150 |  |  |
| | | from | 150 | | |
Abstract
HBV and HCV can develop chronic viral hepatitis. chronic viral hepatitis is defined as hepatitis that lasts longer than 6 months. In chronic viral hepatitis, the viruses live and multiply in the liver for years or decades and cause chronic inflammation of the liver. chronic hepatitis can lead to the development over time extensive liver fibrosis then scarring (cirrhosis), liver failure, and HCC. Patients with chronic viral hepatitis can transmit the infection to others with blood or body fluids.
Liver fibrosis represents a major medical problem worldwide that is associated with significant morbidity and mortality. Beyond being a marker of injury, it appears to play a direct role in the pathogenesis of hepatocellular dysfunction and portal hypertension. Thus assessing the extent and progression of hepatic fibrosis is important.
Liver biopsy is the gold standard for fibrosis staging, although it is limited by its invasive nature, poor acceptance, availability, cost, intra- and inter observer variability, and sampling errors. Alternative tests for evaluation of liver fibrosis have been developed. Among them, serum markers and TE (fibroscan) are the two main techniques which have been compared against histology. The pathology of chronic viral hepatitis represents with portal inflammation, interface hepatitis, confluent necrosis and fibrosis of the hepatocytes. Also the cirrhosis can be represented grossly with naked eye as nodular liver which can be micro or macro nodular.
Summary & Conclusion
96
The transient elastography (TE) is a simple and low-cost device that could be used to assess instantaneously and directly the elasticity of the liver. The measurements are fully noninvasive, and may be performed after a short training period, there is no intra-or interobserver variability and the technique is reproducible.
It is preformed bedside on supine lying patient with arm fully abducted the tip of the probe transducer is placed over the right lobe of the liver through the intercostal spaces. At least 10 vaild measurements should be obtained to get good result. In TE, a shear wave is initiated at the boundary and the interior displacement of the propagating shear wave is imaged with an ultrasound ultra-fast imaging system. As the liver tissue gets stiffer the shear wave gets steeper.
Correlation with fibrosis grade is good with good sensitivity and specificity values and high PPVs (in comparison to liver biopsy) especially in moderate and severe stages of fibrosis (≥ F2) (reaches more than 90%). So because it is completely non invasive and the stiffness is a continuous variable, repeated measurements could show changes in the amount of fibrosis and help follow-up in these patients.
Several studies evaluated the accuracy of FibroScaning, blood tests, or combinations compared with liver biopsy. In patients with chronic viral hepatitis, and others include patients with chronic liver disease of any origin as biliary cirrhosis due to PBC or PSC. Also
Summary & Conclusion
97
patients who are co infected with HIV and HCV are subjected to assess the liver fibrosis.
These studies show that FibroScaning results are reproducible across operators and time. All investigators report that FibroScan’s diagnostic performance is good, indicating that it agrees perfectly with liver biopsy in detection and grading of hepatic fibrosis.
In patients with chronic viral hepatitis it’s essentially to assess them with the ultrasound examination to detect the structural integrity of the liver such as the liver size, the bluntness of the liver edge, the coarseness of the liver parenchyma, nodularity of the liver surface, the irregularity and narrowness of the IVC, PV velocity and spleen size.