Anorectal manometry with a microtransducer.

OBJECTIVE

To find out whether the direction of the sensor of the microtransducer or the position of the subject influenced anorectal manometric pressure recordings; to record resting and squeeze pressures and length of anal canal in five groups divided according to age, sex, and parity, and to study rectal sensitivity and response of intrarectal pressure to rectal distension.

DESIGN

Open study.

SETTING

University Hospital, Linköping, Sweden.

SUBJECTS

87 healthy volunteers with no signs or symptoms of anorectal disease.

INTERVENTIONS

Anorectal manometry with a microtransducer.

RESULTS

Neither the direction of the sensor nor the position of the subject influenced the recordings in five men and four women whose ages ranged from 40-58 years. In 60 further subjects grouped according to age, sex, and parity there was no difference in mean (SD) resting pressure between the groups. Maximal squeeze pressure was significantly greater among men than women, and there was no significant difference between parous and nulliparous women. The voluntary contractile force of the external sphincter was greater in young than older people, and in men compared with women. The functional length of the anal canal was greatest in older men and least in young parous women. In a further 18 volunteers aged 20-86 years rectal distension was felt at 25 (12) ml, and maximal tolerated volume was 202 (75) ml. Mean threshold volume required to release the rectosphincteric inhibitory reflex was 17 (8) ml.

CONCLUSIONS

Neither the direction of the sensor nor the position of the patient influenced the recordings. Resting pressure was the same irrespective of sex, age, or childbirth, but maximal squeeze pressure was significantly higher among men and those less than 50 years old.