Direct dissemination of pathologic abdominal processes through perihepatic ligaments: identification with CT.

The liver is fixed in the right upper quadrant of the abdomen by a complex system of peritoneal reflections, known as ligaments. Embryologic evaluation shows that these ligaments, apparently unrelated, are part of a continuum: the ventral mesogastrium. The areolar tissue within the ligaments constitutes a potential space that links the liver with other viscera and with extraperitoneal sites, allowing direct spread of inflammatory or malignant diseases between these organs and spaces. Knowledge of the normal and pathologic appearance of the ligaments is necessary in order to diagnose dissemination of pathologic processes along them. Computed tomography (CT) is the imaging modality of choice for studying ligamentous involvement by disease. On CT scans, occupation or obliteration of ligamentous fat planes by fluid collections or areas of soft tissue with increased attenuation are the signs of direct spread of disease.