Pediatric urodynamics: a clinical comparison of surface versus needle pelvic floor/external sphincter electromyography.

Urodynamic evaluations were done on 37 children to diagnose voiding pattern abnormalities and/or recurrent urinary infections. Each of 25 children had 2 sets of testing to judge a practical method of urodynamic evaluation. Bipolar anal skin electrodes were compared to bipolar perianal muscle needle electrodes as a means of monitoring the urethral sphincter/pelvic floow electromyographic activity. In addition, the urethral catheter was compared to the suprapubic catheter as a means of monitoring intravesical pressure. The results were similar and statistically significant (p less than 0.001). The remaining 12 children were evaluated based only on the results of bipolar anal skin electrodes and uroflowmetry. The results of both groups clearly demonstrated that surface perianal electrodes are practical, accurate and reliable for the diagnosis and treatment of children with voiding pattern abnormalities. We recommend the use of surface electrodes and a urethral catheter as techniques for the urodynamic evaluation of voiding pattern abnormalities of children without overt neuropathology or extensive urethral operation. Preoperative surface electromyography of the urinary sphincters may prove to be a useful screening test to detect occult dyssynergia in patients who have had failed ureteral reimplants.