Anorectal manometry with water-perfused catheter in healthy adults with no functional bowel disorders

Anorectal manometry provides an objective assessment of anal sphincter pressure and rectal sensitivity and anorectal reflexes in response to distension. However, its clinical utility is hampered by a lack of standardized protocols and normative data from healthy subjects. Previous studies have used water-perfused systems in normal subjects, but some adopted a rapid pull-through technique; others did not evaluate rectal sensations and others did not carefully exclude patients with functional bowel disorders. Objective To evaluate anorectal function in healthy adults without functional bowel disorders, using a water-perfused system with the stationary technique in order to obtain normative values for anorectal manometry. Method Fifty-two healthy volunteers with no Rome II diagnostic criteria for functional bowel disorders, including only nulliparous women, underwent anorectal manometry with a water-perfused system, according to a standardized protocol. Results Maximum squeeze pressure of the anal sphincter as well as the area under the pressure-time curve during squeeze was significantly lower in women than men (P < 0.01), while sphincter length, resting pressure, volume thresholds for reflex inhibitory recto-anal and rectal sensations were similar. Conclusions This study describes a protocol for stationary anorectal manometry using a water-perfused system, and a method for analysing the various parameters obtained during the procedure, as recently suggested in the international literature. It supplies normative data obtained in a population of healthy subjects including nulliparous women, with no functional bowel disorders.