CT diagnosis of a large peritoneal loose body: a case report and review of the literature.

We report a case of a large peritoneal loose body (LPLB), diagnosed on CT. The loose body appeared as a round pelvic mass with central calcifications and a distinct fat plane separating it from adjacent organs. The mass changed its location from the left to the right side of the pelvis within 9 days on repeat imaging. The typical cross-sectional characteristics of a LPLB include a mobile well-circumscribed soft-tissue mass usually with coarse central calcifications. The accurate diagnosis of a LPLB is vital to prevent unnecessary surgical intervention in an asymptomatic patient with an incidentally discovered LPLB.