OBJECTIVETo evaluate the application of anal endosonography in the morphology of internal anal sphincter (IAS), external anal sphincter (EAS) and puborectalis (PR) in order to provide necessary information for analysis of the etiology of fecal incontinence and formulation of the therapeutic schedule.

METHODSFrom December 2010 to November 2012, 18 children of anorectal malformation (n=14) or Hirschsprung's disease(n=4) with fecal incontinence received anal endosonography. The morphology of IAS, EAS and PR was observed. The damage of anal sphincter was classified according to Starck criteria. Anorectal mamometry and anal clinical score were measured simultaneously. Spearman analysis was performed to examine the correlation of anal sphincter damage with anorectal mamometric score and anal clinical score.

RESULTSAccording to Starck criteria, anal sphincter damage was small in 11 children, moderate in 6, and severe in 1. PR damage was found in 4 cases. Starck score was positively correlated with manometric score(P<0.05), while not correlated with anal clinical score(P>0.05).

CONCLUSIONSAnal endosonography can clearly display the morphology of IAS, EAS and PR, and their integrity and damage degree. It is a very valuable technique to evaluate the anal sphincter of the children with fecal incontinence, which however can not reflect the function of anal sphincter and anal continence thoroughly.