Figure 2.

Colovesical fistula in a patient with a prior history of anterior resection for rectal carcinoma. (a) There is a connection (arrow) between the colon and bladder on coronal CT. (b) The colonic end of the fistulous tract (arrow) is seen on axial CT. (c) There is a focus of avid FDG-PET uptake (arrow) present. (d) Fused images confirm that the uptake is within the fistula (arrow) and probably represents urine containing FDG within the fistulous tract. The presence of the fistula and the absence of tumor were confirmed at cystoscopy.