Posterior peritoneal recesses: assessment using CT.

Intraperitoneal compartments may extend posteriorly to the level of known retroperitoneal structures at several locations within the abdomen. These locations include the posterior subhepatic or hepatorenal space, the splenorenal space, the retropancreatic recess, the paracolic gutters, and the pararectal fossae. Because of their posterior location, fluid collections within these compartments may be mistaken radiologically for retroperitoneal masses. The sectional anatomy of these spaces, and particularly their appearance on computed tomographic scans, are illustrated in this paper.