Volume 126, Pages S172-S174 (January 2004) The perspective of a neurologist on treatment-related research in fecal and urinary incontinence  Clare J Fowler  Gastroenterology  Volume 126, Pages S172-S174 (January 2004) DOI: 10.1053/j.gastro.2003.10.006

Figure 1 (A ) The electrode arrangements for recording the latency of the “anal wink,” which is seen with successful placement of the stimulating electrode used in the first stage of sacral neuromodulation. (B) An example of the response of the striated anal sphincter to 4 successive stimulating pulses recorded with a needle electrode. The variability of the response is evident, but the position of the cursor shows that the latency of all these responses is >100 milliseconds. The absence of an earlier response (e.g., a direct motor response at <10 milliseconds) was puzzling at the time, but in retrospect it seems likely that an earlier response was not seen because the recordings were made with a concentric needle electrode (which has a restricted recording volume) inserted on the contralateral side to the sacral foramen-stimulating electrode. This observation does not invalidate the measurement of the latency of the anal wink, which is the bilateral contraction of the sphincter; from the prolonged latency, it may be deduced that the response is afferently mediated. Adapted and reprinted with permission from Fowler et al.14 Gastroenterology 2004 126, S172-S174DOI: (10.1053/j.gastro.2003.10.006)

Figure 2 (A ) Inhibition of reflex bladder contractions recorded under isovolumetric conditions in the chloralose-anesthetized cat during electrical stimulation of the S1 ventral root (5 Hz, 1.5 V, 0.05-millisecond duration). (B) Block of the inhibitory response after administration of gallamine, a neuromuscular blocking agent. Horizontal bars represent duration of stimulation. The vertical calibration represents intravesical pressure in centimeters of water, and the horizontal calibration represents time in minutes. Adapted and reprinted with permission from de Groat et al.19 Gastroenterology 2004 126, S172-S174DOI: (10.1053/j.gastro.2003.10.006)