Bidirectional spread of disease via the subperitoneal space: the lower abdomen and left pelvis.

In early fetal life a persistent interconnection between the peritoneum and retroperitoneum of the abdomen and pelvis is formed--the subperitoneal space (SS). This paper serves to complete the description of the specific anatomical nuances of the SS as they relate to the bidirectional direct spread of disease in the left lower abdomen and pelvis. Described are the two avenues of communication (central and lateral pathways) within this portion of the SS. Selected cases illustrating the bidirectional spread of disease processes within this portion of the SS are reported.