Dynamic anal manometry: physiological variations and pathophysiological findings in fecal incontinence

A recently developed technique for dynamic anal manometry was used to study 40 healthy volunteers and 23 patients with fecal incontinence. Seven parameters of anal function were measured. Intraindividual variation of the parameters was studied in 5 females and 5 males. The results of dynamic anal manometry were compared with standard pull-through static anal manometry and correlated well. During opening of the anal sphincter at rest, compliance increased with increasing distension. Males had higher maximal closing pressures during squeeze and lower anal compliance during squeeze than females. There was no sex differences of the sphincter measurements at rest. Age had little effect, and gender had no effect on the measurements. With standard anal manometry, 6 of 23 patients with fecal incontinence both had maximal resting pressure and maximal squeeze pressure within the normal range. When dynamic anal manometry was used, all 23 patients showed one or more abnormal values. The method of dynamic anal manometry provides an opportunity for a more thorough assessment of anal sphincter function than previous manometric methods.