Bladder neck electrical conductivity in the treatment of detrusor instability with biofeedback.

A new method for controlling the symptoms and objective signs of detrusor instability was investigated in a pilot study. The method uses the activity of the bladder neck, monitored by a conductivity catheter, as a biofeedback signal. Voluntary closure of the bladder neck mechanism abolishes abnormal detrusor activity. Ten severely symptomatic women with detrusor instability were assessed clinically and urodynamically before and after a course of biofeedback. Statistically significant improvements in the symptoms of urgency and urge incontinence were found. Five of the seven women who agreed to have repeat cystometry had stable cystometrograms. There was a statistically significant fall in the mean maximum deflection at rest from 41.5 to 16.5 microA (P less than 0.05) measured during bladder neck electrical conductivity tests before and after treatment.