Balloon Expulsion Test as a Screen for Outlet Obstruction in Children with Chronic Constipation.

Publication Type:

Journal Article


Journal of pediatric gastroenterology and nutrition (2012)


ABSTRACT: Chronic constipation (CC) is a common problem in pediatrics and is often the result of obstructed defecation. OBJECTIVE:: To study the feasibility and efficacy of the balloon expulsion test (BET) in the diagnosis and management of children with CC. METHODS:: Retrospective study comparing BET and High-Resolution Anorectal manometry (ARM). The BET was done together with ARM in 29 children 8-19 with CC. For BET a 60 ml balloon was used. Passage of balloon in 1 minute or less was considered normal. RESULTS:: Fifteen of the 29 children had a normal BET. Of these, 14 also had an ARM, all of which were normal (except for two cases with a hypertonic baseline anal sphincter). Thus 12 of 14 with BET and ARM were normal on both (correlation between the tests = 86%). Of the 14 children that failed BET, 10 had distal abnormalities by ARM, contrast studies, EMG or assessment by a pelvic physical therapist. All patients with a non-relaxing sphincter or outlet obstruction were treated with laxatives, anal sphicter Botox and/or pelvic physical therapy and biofeedback. In follow-up of at least 3 months, all patients with a failed BET were improved. CONCLUSIONS:: We found a high correlation between a normal ARM and BET. If the BET is abnormal and the ARM does not identify a cause for the distal obstruction, additional studies may be needed, including contrast enema, defecography, or EMG. BET appears to be a safe, reliable and useful test in the evaluation and management of CC in children.