Acute extraperitoneal infection

Abstract

By definition, the preperitoneal (also called extraperitoneal or properitoneal) space lies in the abdominal cavity between the peritoneum internally and the transversalis fascia externally. Although the authors use the term preperitoneal throughout this article, in keeping with the popular choice of nomenclature, the more inclusive term, extraperitoneal, is probably preferable because it more clearly includes all of the potential space just external to the peritoneum, including the retroperitoneal area, whereas preperitoneal implies the ventral portion of the extraperitoneal space. Another name for the space is parietoperitoneal,22 which the authors believe to be a good term, although somewhat unwieldy.Within the preperitoneal space is a variable quantity of adipose tissue, loose connective tissue, and membranous tissue. Membranous tissue lies just internal to the transversalis fascia. Perhaps the classic definition of the preperitoneal space is correct, but if one accepts the bilaminar formation of the transversalis fascia into the anterior and posterior laminae, two spaces are formed: (1) one between the peritoneum (i.e., the innermost layer of the abdominal wall) and the posterior lamina of the transversalis fascia and (2) one between the two laminae of the transversalis fascia (Fig. 1). In some cases, the posterior lamina is not well developed and the space is limited by the peritoneum internally and the anterior lamina of the transversalis fascia externally (previously referred to as the transversalis fascia). Both laminae of the transversalis fascia insert inferiorly on the ligament of Cooper. Superiorly, they are perhaps united somewhere at the anterior abdominal wall and then continue upward as the transversalis fascia.The extensions of the [new] and [old] spaces, laterally and posteriorly, have not yet been clearly defined because they extend into the at-large preperitoneal spaces, including the posterior retroperitoneal space and the highly complex preperitoneal spaces of the pelvis.The preperitoneal space of the abdomen is filled with a variable amount of connective tissue and other anatomic entities, such as arteries; veins; nerves; and various organs, such as the kidneys and ureters.