Male pelvis rule16 : Urinary bladder fistula

Axial CT scan through the pelvis following instillation of contrast into the bladder shows a connection (arrows) between the patient's vagina (v) and bladder (b). This is consistent with vesicovaginal fistula.

Plain film radiograph of the pelvis shows an air lucency in the bladder (arrows) in the same patient as above.

Axial CT scan through the pelvis shows an air fluid level (arrows) in the bladder (b). In the absence of instrumentation, considerations include fistula to a viscus or to the vagina or to the skin. Infection is a less likely possibility as emphysematous cystitis