الفهرس 
ANATOMY OF THE LIVEROnly 14 pages are availabe for public view
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Abstract
Liver transplantation is performed for a variety of irreversible acute , chronic liver diseases for which no other satisfactory therapy is available.
With considerable improvement in the surgical technique in the last years and new immuno-suppressive therapy, overall patients’ survival rates at 1 and 3 years are 85. 6% and 75. 9% respectively.
Understanding the anatomy of the liver and biliary system and the pathology of their diseases which require liver transplantation is very valuable for their post operative assessment with US and Doppler.
Knowledge of normal radiological appearance of the transplanted liver permit early detection of complications.
Vascular and nonvascular complications may occur after liver transplantation. Vascular complications include thrombosis and stenosis of the hepatic artery, portal vein, or inferior vena cava, as well as hepatic artery pseudoaneurysms. Nonvascular complications include biliary complications as leaks, strictures, stones or sludge, and recurrent neoplasia or posttransplantation lymphoproliferative disorder. Parenchymal disease may take the form of a focal mass or a diffuse parenchymal abnormality. Perihepatic fluid collections and ascites are common after liver transplantation.
US, being cheap, safe, non invasive and accurate is the primary imaging modality in the detection and follow –up of early and delayed complications of liver transplantation.
Gay-scale US is first performed to assess the site, size and echo pattern of the transplanted liver, focal lesion of liver graft, intra or extra hepatic ducts and presence of intra abdominal fluid collection so it is an initial step and also a base line for further follow up.
Color Doppler considered the investigation of choice for early detection and late follow up of any postoperative complications even before clinical indications. It is done routinely after liver transplantation from the first day postoperatively, and it is performed after gray-scale US.
Combined use of color and spectral Doppler US parameters resulted in diagnostic sensitivity of 100% and specificity 99%.
Color Doppler US is very important in early detection of vascular complications { as stenosis, thrombosis and pseudo aneurysm} of hepatic artery, portal vein, IVC and hepatic vein especially for early diagnosis of stenosis as severe stenosis can leads to allograft rejection and progress further to the development of all complications as it progress to thrombosis.
Gray scale US and color Doppler has also greater ability for early diagnosis of recurrence of hepatocellular carcinoma and recurrence of liver parenchymaus diseases.
Liver biopsy is usually performed to exclude rejection, recurrent hepatitis, drug effect or other parenchymal disease as a cause of allograft dysfunction.
Color Doppler US (CDUS) is performed to ensure perfect vascular reconstruction after hepatic reperfusion.
For the immediate assessment of general condition and early detection of vascular complications CDUS is becoming the modality of choice to evaluate hepatic hemodynomis.
There are various imaging modalities to detect post operative complications. The diagnostic usefulness of a modality depends mainly on the patient’s characteristics, the clinical purpose of the imaging evaluation, and the expertise of imaging professionals.