Pharmacologic treatment for detrusor overactivity

Urethral Sphincter EMG as Event Detector for Neurogenic Detrusor Overactivity

The aim of this study was to investigate the feasibility of using external urethral sphincter electromyogram (EMG) (EUSEMG) to detect the onset of detrusor contractions in patients with both neurogenic detrusor overactivity (NDO) and detrusor sphincter dyssynergia (DSD). Detrusor pressure (Pdet) and EUSEMG was recorded in 23 neurogenic patients during slow artificial bladder filling. The time delay between the onset of a detrusor contraction and the onset of EUSEMG activity was calculated together with the detrusor pressure increase related to this delay. Of 23 patients enrolled, 12 patients showed both NDO and DSD. Of these 12 patients, 10 had a strong correlation between detrusor pressure and EUSEMG. One patient in this group was excluded due to a storage pressure above 30 cm H2O. Two detection methods were applied on the remaining 9 patients. Method 1 was a root mean square (RMS)-integrator with simple thresholding. This approach had a good sensitivity but also a poor specificity (many false-positive detections). Detection method 2 included a kurtosis-based scaling function, which was multiplied to a similar RMS-integrator as used in method 1. Onset detection occurred before Pdet exceeded 18 cm H2O with both methods. However, method 1 resulted in 14.1 +/- 12.8 false-positive detections during one bladder filling. Pdet at onset detection was on average 1.0 +/- 1.1 cmH2 0 higher with detection method 2 but the number of false-positives was reduced by 95.8%. This paper demonstrates the feasibility of using EUSEMG to estimate the onset of a detrusor contraction in selected patients.

The impact of detrusor overactivity on the management of stress urinary incontinence in women

The presence of overactive bladder symptoms, urodynamic detrusor overactivity, and urge incontinence can complicate the diagnosis and management of stress urinary incontinence in women. The exact pathophysiology of mixed incontinence is not well characterized; in some patients, the stress and urge etiology may be pathologically linked. The role of urodynamics in evaluating patients with mixed incontinence remains controversial. Conservative therapies, such as bladder training, pelvic floor exercise, biofeedback, and electrical stimulation, offer moderate success in women with mixed incontinence. Surgery (colposuspension, bladder neck pubovaginal slings, and midurethral slings) offers excellent subjective and objective cure rates in patients with mixed incontinence. Preoperative detrusor overactivity is cured consistently 50%of the time with colposuspension and slings. Overall, the presence of preoperative detrusor overactivity does not appear to significantly worsen the outcome of conservative and surgical treatments for stress urinary incontinence in women.

The emergence of new drugs for overactive bladder

Overactive bladder is a common and distressing problem. Standard therapy is directed towards modifying the detrusor motor sensitivity and response via anticholinergic medication. Currently available medications are reviewed and alternative targets for treatment are presented.