Objective: To investigate the causes of voiding dysfunction and new detrusor instability after colposuspension.
Design: Prospective, observational study.
Setting: Urogynaecology unit, district general hospital.
Population: Seventy-seven women undergoing colposuspension for genuine stress incontinence.
Methods: The following factors were investigated: 1. bladder neck elevation by magnetic resonance imaging before and after surgery; 2. urethral compression by measuring bladder neck approximation to the pubis with magnetic resonance imaging after surgery (anterior compression) and the distance between the medial stitches during surgery (lateral compression); 3. clinical and urodynamic factors.
Main outcome measures: 1. Post-operative voiding function (i.e. first day of voiding and day of catheter removal); 2. objective evidence of detrusor instability three months post-operatively.
Results: Pre-operative peak flow rate (P = 0.004), straining during voiding (P = 0.005), increasing age (P < 0.001), operative elevation (P < 0.001) and anterior urethral compression (P = 0.001) were associated with the number of days of post-operative catheterisation. Increasing age (P = 0.02), previous bladder neck surgery (P = 0.04), operative elevation (P = 0.049) and anterior urethral compression (P < 0.001) were associated with detrusor instability at three months.
Conclusion: Surgical factors (bladder neck elevation and compression) are associated with voiding dysfunction and detrusor instability after colposuspension. These findings have implications for prevention.