Normal values in anal manometry and rectal sensation: a problem of range

Area of Science:

• Gastroenterology
• Physiology
• Anorectal Function

Background:

• Anal manometry is crucial for assessing anorectal function.
• Understanding normal variations in anal pressure and sphincter length is essential for diagnosing and treating anorectal disorders.
• Age and sex are known factors that can influence physiological parameters.

Purpose of the Study:

• To investigate the influence of age and sex on anal pressures and sphincter length in healthy individuals.
• To evaluate age-related changes in rectal sensitivity and the distension reflex.
• To establish normative data for anal manometry parameters.

Main Methods:

• Anal manometry was performed on 80 healthy volunteers (40 men, 40 women) aged 20-87 years.
• An open-tip perfusion system with a 4-sideport catheter and terminal balloon was utilized.
• Measurements included maximum basal pressure (MBP), maximum squeeze pressure (MSP), sphincter length, rectal distension reflex, and rectal perception volume.

Main Results:

• Maximum squeeze pressure (MSP) was significantly higher in men than women (p < 0.001).
• Both MBP and MSP decreased significantly with age (p < 0.001).
• Sphincter length was greater in men and correlated with MBP; rectal sensitivity decreased with age.

Conclusions:

• Normal anal pressures and sphincter length exhibit wide ranges and are influenced by age and sex.
• Age-related decline in rectal sensitivity and altered distension reflex parameters were observed.
• These findings are critical for interpreting anorectal manometry and guiding therapeutic decisions in patients with anorectal disorders.