peritoneal loose body

Peritoneal loose bodies or peritoneal mice are calcified pieces of necrotic tissue found in the peritoneal cavity. They are usually asymptomatic and small, ranging from 0.5 to 2.5 cm in size, but rarely may be up to 5 to 10 cm in size.

Clinical presentation

Loose bodies are usually asymptomatic .

Pathology

Peritoneal loose bodies are formed by the torsion and autoamputation of epiploic appendages. Epiploic appendages are suscepitible to torsion due to their narrow pedicle. Acute torsion produces epiploic appendagitis which is normally self limiting. However, chronic torsion results in the ischemia and subsequent calcification, fibrosis and autoamputation of the appendage with it then being released into the peritoneal cavity .

Radiographic features

CT
  • centrally calcified soft tissue mass
  • mobile mass, moving to the dependent position of the patient
  • usually 0.5 to 2.5 cm in diameter, however may be up to 10 cm in size - termed "giant" loose body

Treatment and prognosis

Rarely they have been implicated in the development of urinary retention and bowel obstruction. If symptomatic, surgical removal may be required.