Urodynamic changes in voiding after anti-incontinence surgery: An insight into the mechanism of cure

Objectives. To measure the effect on voiding pressure and flow rate of three different operations for stress urinary incontinence. Methods. In a previous study of cure rates, 289 women with genuine stress incontinence and genital prolapse were prospectively allocated in a randomized manner to one of three procedures: the Burch retropubic urethropexy, anterior repair, or the modified Pereyra procedure. In the current derivative study, we retrospectively evaluated the urodynamic indicators of voiding dysfunction in the original subjects preoperatively and at the 1-year postoperative follow-up visit. Results. One hundred thirty-two charts were available for review. One year after surgery, pressure and flow during voiding were altered to more obstructive levels with the suspension procedures (Burch and modified Pereyra). The proportion of patients with obstructive and equivocal voiding patterns after the suspension procedures was significantly greater than after anterior repair. Conclusions. This post hoc comparison of randomized data shows a difference in postoperative voiding indexes between suspension procedures and anterior colporrhaphy. Successful bladder neck suspension depends on altering the pressure and flow during voiding to more obstructive levels. Suspension procedures alter the voiding pressure and flow toward obstruction to a greater extent than anterior repair.