Abdominal wall electromyography: a noninvasive technique to improve pediatric urodynamic accuracy.

Abdominal wall electromyography, using sticky surface patch electrodes placed on the rectus abdominus muscles, was used during noninvasive urodynamic studies in 60 children to detect straining. Straining, which usually was imperceptible to the examiner, occurred in 64 per cent of neurologically normal children. Urodynamics identified detrusor-sphincter dyssynergia during straining to void but reverted to normal when the same children voided without straining. Because the urodynamic findings that characterize detrusor-sphincter dyssynergia are mimicked by straining and other common urologic entities, the potential for misdiagnosis is great unless some assessment of intra-abdominal pressure is made during neurourologic testing.