Clinical aspects of detrusor instability and the value of urodynamics: a review of the evidence.

The term unstable bladder was introduced as a description of an observation not implying pathology. In some patients, special provocative maneuvers may be needed to demonstrate it. It is variable from one test to another. It is observed in some healthy volunteers. Therefore, detrusor instability observed during urodynamic testing is not a medical condition and may not necessarily be clinically relevant. In an individual patient the clinical relevance of the observation must be judged in relation to symptoms and signs of bladder dysfunction. In the field of female incontinence there is general agreement that, statistically, the pre-operative observation of detrusor instability implies poorer results of anti-incontinence surgery. However, some incontinent patients with detrusor instability are improved by surgery. Consequently, different authors draw different conclusions about the clinical relevance of detrusor instability, but no author considers that detrusor instability is an absolute contraindication to surgery for stress incontinence.