Biofeedback methodology: does it matter how we teach children how to relax the pelvic floor during voiding?

Biofeedback is a noninvasive treatment that has been documented to be helpful for children with daytime wetting and/or urinary tract infection secondary to voiding dysfunction. We wish to determine the effectiveness of biofeedback in a large population of children presenting with voiding dysfunction, and evaluate differences between 2 different methods with regard to resolution of symptoms, improvement of objective measurements and patient satisfaction.

The charts of 102 consecutive patients treated with biofeedback were reviewed. Of the patients 21 were asked to void 4 to 8 times in 6 hours seated in front of a uroflow device while receiving coaching by a staff member (method 1), 56 were taught pelvic floor relaxation techniques in front of a computer monitor that displayed electromyogram readings for 45 to 90 minutes (method 2), and both methods were used in 25. Outcome variables were obtained through chart review and telephone contact, and included resolution of symptoms, elimination of urinary tract infection, character of voiding curve, post-void residual, decrease in relaxation score and parental satisfaction.

Females comprised 79% of the population and median age at first treatment was 7.7 years (range 4.3 to 15.4 y). Daytime wetting was seen in 84% and recurrent urinary tract infection in 66% of patients. Among children with daytime wetting there was 100% success or improvement with method 1, 91% with method 2 and 80% with both methods (p not significant). Among those with urinary tract infection, 25% had subsequent infection with method 1, 25% with method 2 and 31% with both methods (p not significant). Normalization of the flow curve was seen in 94% with method 1, 67% with method 2 and 30% with both methods. Patients using both methods had a significantly greater post-void residual compared to patients using method 1 (0 versus 33%, p = 0.003). Relaxation scores decreased a median of 6.5% in with method 2 and 20% with both methods. After a median followup of 1.8 years 98% of parents expressed satisfaction with biofeedback with more than 80% indicating a high degree of satisfaction.

Reduction of daytime wetting and urinary tract infection can be achieved regardless of the type of biofeedback used. Although symptoms improved, patients using a shorter but more intensive approach aimed at teaching control of the pelvic floor musculature were more likely to demonstrate persistent post-void residuals and abnormal flow curves. A considerable degree of enthusiasm was reported using both of these non-invasive forms of treatment.