A critical view on the value of urodynamics in non-neurogenic incontinence in women.

The requirements for reliable urodynamics are standardized techniques, including uniform pressure sensors, filling rates, position and posture during the investigation, and uniform diuresis. Physiological variations in flow and urethral pressure profile (UPP) (menstrual cycle, intensity of coughing, circadian variations) must be considered. Parameters of the UPP (maximum (closure) urethral pressure, pressure-transmission ratio and leak-point pressure) are useful if interpreted with caution. Uninhibited detrusor contractions are more frequently recorded in ambulatory urodynamics, and range from 'subthreshold' to very strong. No quantification formulae correlate with subjective symptoms or degree of urge (incontinence). Mixed incontinence can make the results of surgery worse, but do not so necessarily. Postoperative dysuria cannot be predicted from urodynamics, as surgical factors are more important. Electromyography is not useful in non-neurogenic female incontinence. For routine nonneurogenic incontinence extensive urodynamic testing can be reduced to one pressure measurement; more complicated cases must be tested by a physician with large practical experience and a theoretical background.