Detrusor-external sphincter dyssynergia.

Detrusor-external sphincter dyssynergia is characterized by involuntary contractions of the external urethral sphincter during detrusor contractions. A review of 550 consecutive patients who underwent urodynamic evaluation revealed that this condition was found only in patients who had involuntary detrusor contractions owing to well defined neurologic lesions of the suprasacral spinal cord. All patients with supracervical neurologic lesions had synergistic voiding patterns. We conclude that bladder-external sphincter dyssynergia is a neurologic condition owing to interruption of the spinal pathways connecting the pontine mesencephalic and the sacral micturition centers. In the absence of such a neurologic lesion one should be extremely cautious in making this diagnosis.