The creation of a sigmoidovesical fistula by a process primary in either the sigmoid flexure of the colon or the urinary bladder is a serious complication which fortunately confronts the surgeon only infrequently. It engenders so poor a prognosis that the choice of treatment must be guided by great care, for the mortality resulting from surgical attack is extremely high. The pathologic entity responsible for the formation of such an abnormal channel is usually primary in the sigmoid and but rarely has its origin in the bladder. Occasionally an inflammatory process external to both sites may be the responsible agent. Parham and Hume,1 Sutton2 and Kellogg3 have each presented excellent classifications of the causes of sigmoidovesical fistula.
The frequency of communication between the sigmoid flexure of the colon and the urinary bladder as compared to other intestinovesical fistulas has gradually increased since the earlier reports. Pascal4