Fish bone migration to the urinary bladder after rectosigmoid colon perforation

Figure 1 Initial computed tomography image. A, B: Computed tomography revealed a 3 cm, thin, curvilinear object with a high density within a 5 cm sized fluid collection adjacent to the urinary bladder, which can be regarded as a foreign body and abscess formation (arrow); C: Wall of the rectosigmoid colon (arrow) is thickened, suggesting that the rectosigmoid colon was perforated.