Figure 1.

(A) Station-pull through manometry of the anal sphincter at rest. A perfused-tube catheter is pulled through the anal sphincter in 1 cm increments (arrows). Rectal pressure is used as a baseline (red line). The anal canal is indicated in green. (B) Normal squeeze response. Maximum squeeze pressure is defined as the difference between intrarectal pressure and the highest pressure that is recorded at any level within the anal canal during the squeeze maneuver. (C) Rectoanal inhibitory reflex. The presence of rectoanal inhibitory reflex is recorded when the balloon is distended with a 50 mL volume of air. (D) Cough reflex. Manometric findings in a patient with fecal incontinence, showing a negative anus-to-rectum pressure gradient during coughing.