Short pelvic floor EMG lag time II: use in management and follow-up of children treated for detrusor overactivity

Abstract

Objective: To determine utility of short pelvic floor electromyography (EMG) lag time in monitoring therapeutic response in children with idiopathic detrusor overactivity (DO) and quiet EMG during voiding (idiopathic detrusor overactivity disorder, IDOD).

Patients and methods: 162 consecutive normal children (77M, 85F) diagnosed with IDOD and short EMG lag time were reviewed. All were treated with combined standard urotherapy and anticholinergics. Pre-treatment uroflow/EMG parameters were compared with on-treatment parameters.

Results: Median age at evaluation was 6.8 years and median EMG lag time was 0 s; 110 children had repeat uroflow/EMG studies while on anticholinergic therapy. With a median follow-up of 18.7 months, mean EMG lag time increased from 0.7 to 2.2 s and % expected bladder capacity for age (EBC) increased from 0.68 to 0.98 (both p < 0.01). EMG lag time increased in all patients while on therapy and normalized in 83 patients (75%).

Conclusion: A short EMG lag time on noninvasive uroflow/EMG in a patient with urgency can be a surrogate for urodynamics study (UDS) in diagnosing DO and objectively monitoring response to therapy. When effectively treated, children with DO have amelioration of their lower urinary tract symptoms (LUTS) and normalization of both EMG lag time and bladder capacity.

Keywords: Detrusor overactivity; Overactive bladder; Pediatrics; Uroflowmetry with EMG; Voiding disorders.