Gossypiboma in the early post-operative period: a diagnostic problem

A gossypiboma (a retained surgical sponge) usually has the characteristic appearance on CT of a soft tissue mass with air-bubbles and a whirl-like pattern. This finding may be confused in the early post-operative period with an abscess, especially when a fistula is present. We describe two patients, in whom this diagnosis was initially missed. A soft tissue mass containing air-bubbles in the early post-operative period with or without a fistula should include a retained pad, in the differential diagnosis.