Figure 1.

Detrusor pressure in response to electrical stimulation (bar) of the urethra. Electrical stimulation of the distal urethra at 35 mA, 20 Hz, evoked a bladder contraction, which generated some voiding, but the bladder neck was occluded by a Foley balloon and the voided volume was not recorded. Bladder volume prior to stimulation was approximately 90% of the volume threshold for distention-evoked contractions (V_th). Peak detrusor pressure increase evoked by stimulation was approximately 70 cmH₂O.