CT demonstration of colovesical fistulae secondary to diverticulitis.

Colovesical fistula, a not infrequent complication of diverticulitis, can be difficult to demonstrate by commonly used diagnostic imaging modalities. We present four cases in which computed tomography was used to detect the presence of such a fistula. Computed tomography readily detected air within the bladder earlier and without equivocation when compared with other imaging techniques. It was useful also in the assessment of the extent and the degree of pericolonic inflammation, thus playing an important role in preoperative surgical planning and postoperative follow-up.