Carbon dioxide urethral pressure profilometry before and after external sphincterotomy in spinal cord injury patients.

Seven spinal cord injury patients were studied before and after transurethral external sphincterotomy with combined electromyographic and gas urethral pressure profilometry. The technique was simple, rapid, accurate and reproducible in evaluating the completeness of external sphicterotomy. A significant reduction in maximum urethral closure pressure, as well as in the residual urine volume, was a consistent after spincterotomy. The electromyographic profile showed evidence of periurethral striated muscle activity preoperatively in 2 patients with lower motor neuron lesions in whom the bulbocavernosus reflex could not be elicited. Thus, absence of the bulbocavernosus reflex did not eliminate sphincter reflex activity.