Efficacy/Safety of Midurethral Sling

Overview

The trans-obturator tape (TOT), which exhibits a satisfactory cure rate and a relatively diminished invasiveness, has been increasingly accepted as a surgical treatment of stress urinary incontinence (SUI) patients. Nevertheless, in contrast to the well-recognized therapeutic benefit of the enhanced resistance to the bladder continence during urine storage, if the voiding function of the bladder adapts to the TOT-enhanced outlet resistance has not been adequately investigated. This study retrospectively assayed the voiding efficacy of each voiding cycle, to clarify if the thermodynamic efficacy of the bladder was modified in response to the TOT surgery.

The urodynamic study included free uroflowmetry, postvoid residual, filling and voiding cystometry, and a urethral pressure profile. The filling cystometry and urethral pressure profile were performed with 37 degrees C normal saline similar to body temperature at an infusion rate of 80 ml/min. All patients received a pre- and a post-operative urodynamic evaluation, in which pre-operative evaluation was conducted 1-4 weeks before TOT procedure, and post-operative evaluation was done at 4-6 weeks follow-up. Complete multichannel urodynamic studies including free uroflowmetry, filling and voiding cystometry, and urethral pressure profile was performed in each patient. The urodynamic parameters measured were the maximum flow rate (Qmax), voided volume, post-void residual volume (PVR), and detrusor pressure at Qmax (Pdet. Qmax). The filling cystometry and urethral pressure profile were performed with 37 degrees C normal saline at an infusion rate of 80 ml/min. All data were recorded and analyzed using a Medical Measurement Systems (MMS UD-200, Enschede, The Netherlands). All data in this study will be expressed as mean ± SEM. After checking the normality and variance of data, two-way ANOVAs were used to assess the difference in values among testing groups and time points; and post hoc Student-Newman-Keuls tests were used to compare the means of groups when there was a significant difference between groups. Significance was set at p\<0.05.