ABSTRACT
To understand the various organs and nerves involved with urinary control, we like to visualize the micturition process as a complex of neural circuits in the brain and spinal cord that coordinate the activity of smooth muscle in the bladder and urethra ( 1-3 ). These circuits act as on-off switches to alternate the lower urinary tract between two modes of operation: storage and elimination. Injuries or diseases of the nervous system in adults can disrupt the voluntary control of micturition, causing the re-emergence of reflex micturition and resulting in detrusor overactivity and urge incontinence ( Fig. 23.1 ) ( 1-4 ). Because of the complexity of the central nervous control of the lower urinary tract, urgency incontinence can result from a variety of neurologic disorders. In addition, urgency incontinence may be due to intrinsic detrusor myogenic abnormalities, resulting in detrusor overactivity (5) .
