Periportal

Periportal is an anatomical term used to describe the region surrounding the portal triad within the liver. The portal triad consists of the portal vein, the hepatic artery proper, and the bile duct, all enclosed by a connective tissue framework together with accompanying nerves and lymphatics. Periportal tissue is the area immediately around these portal structures.

In liver histology and anatomy, the liver is organized into lobules and functional zones. The periportal zone, also known as zone 1, contains hepatocytes closest to the portal triads and receives the most oxygenated blood from the hepatic artery and portal vein. This zone carries out many oxidative and biosynthetic activities and contrasts with the centrilobular or pericentral zone (zone 3), which lies near the central vein and is more susceptible to hypoxic injury.

In pathology and radiology, periportal is used to describe changes that are centered around the portal tracts. Periportal inflammation, periportal fibrosis, and periportal edema are patterns that can be observed in various liver diseases. Periportal edema may be detected on imaging as thickened periportal spaces and can be associated with conditions such as congestive heart failure or biliary obstruction, depending on the clinical context.

The term is distinct from periportal and pericentral references used in describing the distribution of injury or disease within the hepatic acinus model. Recognizing periportal involvement helps in interpreting patterns of liver injury, cholestasis, and fibrosis, as well as in correlating imaging findings with underlying hepatic architecture.