The liver is the largest internal organ of the human body. The liver weight approximately 1.2 to 1.5 Kg in the adult it is located beneath the diaphragm in the right upper quadrant of the abdomen and is protected by the ribs and held in place by ligamentous attachment. The normal color of the liver is brown and the external surface is smooth (Janelle et al., 2010).
1.1.2 Function of The Liver:
The liver is the largest internal organ of the human body. It is a functionally complex organ that plays a critical biochemical role in the metabolism, digestion, detoxification, and elimination of substances from the body. The liver is involved in a number of excretory, synthetic, and metabolic functions, all of which are essential to life. The liver is unique in the sense that it is a relatively resilient organ that can regenerate cells that have been destroyed by some short-term injury or disease. However, if the liver is damaged repeatedly over a long period of time, it may undergo irreversible changes that permanently interfere with its essential functions (Janelle et al., 2010).
1.1.3 . Liver Anatomy:
220.127.116.11. Gross Anatomy:
The liver is about 2% of bodyweight in the adult. The liver receives its blood supply from two sources (the portal vein, 80%) which drains the spleen and intestines. The remaining (oxygenated blood, 20%) is delivered by the hepatic artery. The portal vein is formed by the union of the splenic and the superior mesenteric veins with the inferior mesenteric vein. These are draining into the splenic vein. The common hepatic artery is a branch of the celiac artery along with the splenic and left gastric arteries. Occasionally, the hepatic artery has accessory and/or replaced vessels supplying the liver these accessory or replaced are a branch of the proximal superior mesenteric artery, while the accessory or replaced left hepatic artery is a branch of the left gastric artery ( Hiatt et al., 2013).
Externally, the liver is divided by the falciform ligament into a larger right lobe and a smaller left lobe. The falciform ligament attaches the liver to the anterior abdominal wall. Its base contains the ligamentum teres, which has a remnant of the vestigial umbilical vein. In cirrhosis, this veinrecanalizes as a result of portal hypertension based on Couinaud classification, the liver is divided into eight independent functional segments. Each segment has its own portal pedicle consists of the hepatic arterial branch, portal branch, and the bile duct with a separate hepatic venous branch that provides outflow. The numbering of segments is in a clockwise manner. Segments II and III, are known as the anterior and posterior segments of the left lobe, respectively. They are known collectively as the left lateral segment of the liver and the topographic left lobe. Segment IV is the medial segment of the left lobe. Segments II to IV make up the functional left lobe of the liver.
The right lobe of the liver is made up of segments V and VIII (the anterior segments, and segments VI and VII (the posterior segments). Segment I, the caudate lobe, is located posteriorly. The outflow of the liver is provided by the three hepatic veins. The right hepatic vein divides the right lobe of the liver into anterior and posterior segments. The middle hepatic vein divides the liver into the left and right lobes which runs in the same plane with the inferior vena cava and the gallbladder fossa. Similarly, the left hepatic vein divides the left liver into medial and lateral segments. The portal vein divides the liver into the upper and lower segments. The segmental liver anatomy is important to radiologists and surgeons, especially in view of the need for an accurate preoperative localization of focal hepatic lesions (Soler et al., 2013).