Fig. 1: Pressuretime curves calculated after normalization by the first measured point and calculation of the passive state in 30 control children (diamonds) and 30 children with constipation (squares). Each point is the mean of all distension (from 20 to 50 mL). The decrease in the normalized pressure was significantly different in the 2 groups: mean values were higher in patients with constipation, and an asymptotic (level) pressure was reached in controls but not in patients with constipation.