Assessing colonic anatomy normal values based on air contrast enemas in children younger than 6 years

Background: Contrast enemas with barium or water-soluble contrast agents are sometimes performed in children with severe intractable constipation to identify anatomical abnormalities. However there are no clear definitions for normal colonic size or abnormalities such as colonic dilation or sigmoid redundancy in children. Objective: To describe characteristics of colonic anatomy on air contrast enemas in children without constipation to provide normal values for colonic size ratios in children. Materials and methods: We performed a retrospective chart review of children aged 0–5 years who had undergone air contrast enemas for intussusception. The primary outcome measures were the ratios of the diameters and lengths of predetermined colonic segments (lengths of rectosigmoid and descending colon; diameters of rectum, sigmoid, descending colon, transverse colon and ascending colon) in relation to the L2 vertebral body width. Results: We included 119 children (median age 2.0 years, range 0–5 years, 68% boys). Colonic segment length ratios did not change significantly with age, although the differences for the rectosigmoid/L2 ratio were borderline significant (P = 0.05). The ratios that involved the rectal and ascending colon diameters increased significantly with age, while diameter ratios involving the other colonic segments did not. Differences by gender and race were not significant. Conclusion: These data can be used for reference purposes in young children undergoing contrast studies of the colon.