Background: We aimed to evaluate anorectal function of normal infants and children through three dimension high-definition anorectal manometry (3D ARM) to fill the research blank in this area.
Methods: From November 2014 to January 2019, 104 normal infants and children among patients who underwent 3D ARM were divided into four groups according to age (≤1 month; >1 month to ≤1 year; >1 year to ≤4 years and >4 years) and reviewed. The following parameters were performed: the length of anorectal high-pressure zone (HPZ), the resting pressure of HPZ (HPZ-rest), the squeezing pressure of HPZ (HPZ-sqze), recto-anal inhibitory reflex (RAIR), and pressure distribution of the anal canal. Graphpad Prism 7.0 software was used for statistical analysis.
Results: HPZ, HPZ-rest, and HPZ-sqze increased with age. There were differences in HPZ-rest and HPZ-sqze between the groups (p < 0.05). Sex had a significant effect on HPZ, but not on HPZ-rest and HPZ-sqze. The HPZ of males was higher than that of females among those ≤1 month old (p < 0.05). RAIR (-) was found in 17 patients (16%) for whom Hirschsprung's disease were excluded by biopsy, and these patients had regular defecation during follow-up. Most of the patients (85%) older than 1 year had a symmetric anal pressure distribution during the contracting period (p < 0.05).
Conclusions: Anal canal function parameters gradually increased with age in normal infants and children which demonstrated the important role of age in evaluation, and these parameters can provide a reference for postoperative evaluation of anal canal function.
Keywords: anorectal function; anorectal manometry; children; infant.
© 2022 John Wiley & Sons Ltd.