Urodynamic assessment of patients with stress incontinence: how effective are urethral pressure profilometry and abdominal leak point pressures at case selection and predicting outcome?
PURPOSE OF REVIEW: Disagreement exists as to the extent of evaluation required prior to offering surgical intervention for the treatment of stress urinary incontinence in women. While few would argue that additional information can be gleaned from a properly performed urodynamic investigation, it remains unclear exactly which women would most benefit from such preoperative study, and if urodynamic evaluation definitively improves treatment outcome. Since such invasive studies may not be widely available in certain areas, can be costly, and are associated with a low, but defined risk of bladder infection, it is imperative that the appropriate indication for preoperative urodynamic evaluation be carefully defined. This review highlights recent reports and controversies concerning the use of urodynamics (focusing on leak point pressure testing and urethral pressure profilometry) prior to surgical treatment for stress urinary incontinence. RECENT FINDINGS: There remains no clear consensus as to whether urodynamic testing enhances surgical outcome of stress urinary incontinence treatments by improving case selection or altering the surgical approach based on study findings. As treatment strategies for stress urinary incontinence have developed over the last several years to a more uniform approach, it is less clear that the severity of stress urinary incontinence, based on either abdominal leak point pressure or urethral pressure profilometry will influence the choice of surgical technique. Furthermore, there is little evidence to suggest that patients with more severe forms of stress urinary incontinence by urodynamic testing fare more poorly after the most commonly offered surgical treatment than those with less severe forms. There are certain sub-populations of women who appear to be at higher risk of voiding dysfunction following incontinence surgery, and urodynamic testing may aid in identifying this group. SUMMARY: It is not apparent that either abdominal leak point pressure measurement or urethral pressure profilometry can accurately predict which patients will achieve the best outcome of surgical treatment for stress urinary incontinence. Other parameters assessed during urodynamic evaluation might provide prognostic information regarding the risk of voiding dysfunction postoperatively and the possibility of persistent urge-related leakage following surgery, though not directly predict cure. A multi-institutional randomized study comparing the outcome between patients in whom treatment was determined with the urodynamic information known, compared with patients in whom this information was unknown would further enhance our understanding of the usefulness of urodynamics in the preoperative evaluation of women with stress urinary incontinence.