ABSTRACT
Anal resting pressure is based on active forces generated by the smooth and striated sphincter muscles and on the expansion of the blood-filled anal vascular cushions. Anal continence is a complex phenomenon based on a sphincter barrier, reservoir function, and sensation components. The resting anal pressure, however, is important for the retention of gas and liquid stool, i.e., when the function of the flap-valve component of the continence mechanism is ineffective. Anal resting pressure is higher in men than in women. Most of the studies found that anal pressure tends to decrease with age, especially after menopause and after the age of 70. Anal resting pressure is influenced by methodological factors, age and gender. Anal manometry is not a standardized investigation technique. The smooth internal anal sphincter continuously generates electrical and mechanical rhythmic activity. Its pure myogenic activity is weak but greatly enhanced by the sympathetic innervation.
