extrahepatic

Extrahepatic is a medical term meaning located outside the liver. The word combines extra, meaning outside, with hepatic, relating to the liver. In clinical use, extrahepatic contrasts with intrahepatic, which refers to tissues or processes within the liver parenchyma.

In anatomy, extrahepatic commonly describes structures that lie outside the liver proper. A prominent example is the extrahepatic biliary tract, which includes ducts such as the common bile duct that conduct bile from the liver toward the intestine. Diseases of these ducts, including obstruction or malignancy, are often described as extrahepatic cholangiopathies. The term is also applied to disease spread or involvement: cancers may metastasize to sites outside the liver (extrahepatic metastases) as opposed to metastases confined to the liver (intrahepatic metastases).

Clinical relevance rests on location. Distinguishing extrahepatic from intrahepatic disease influences diagnostic imaging strategies, staging, and treatment planning. Imaging modalities such as ultrasound, computed tomography, magnetic resonance imaging, and magnetic resonance cholangiopancreatography are used to determine whether a lesion or process is extrahepatic. Surgical and therapeutic approaches vary by location; for example, management of extrahepatic biliary obstruction or cholangiocarcinoma often involves procedures targeting ducts outside the liver, whereas intrahepatic conditions may require different liver-directed strategies.

In summary, extrahepatic denotes anything outside the liver, with special emphasis in medicine on anatomical regions, pathologies, and disease processes that occur beyond the hepatic parenchyma.