title: Fecal retention in childhood: Evaluation on ultrasonography.
abstract: BACKGROUND
  To assess the usefulness of rectal diameter measurement on ultrasonography as a diagnostic tool for fecal retention in children.
  
  
  METHODS
  One hundred children (median age, 5.0 years), consisting of 80 with functional constipation and 20 without constipation, participated in the study. All patients underwent physical examination that included digital rectal examination. Forty-five children underwent ultrasonography in three differential planes: transection above the symphysis; under the ischial spine; and at the bladder neck. The measurement of the rectal diameter at the transection above the symphysis could most easily detect fecal retention and had the closest correlations with retention among the three planes.
  
  
  RESULTS
  Rectal diameter was wider at all measuring points (35.2 vs 20.9 mm above the symphysis, P < 0.0001; 35.7 vs 24.0 mm under the ischial spine, P < 0.0001; and 19.4 vs 8.7 mm at the bladder neck, P < 0.0001) in children with fecal retention than in those with no fecal retention. With regard to presence of constipation, children with fecal retention had a wider rectal diameter above the symphysis than those with no fecal retention (children with functional constipation, 35.3 vs 20.0 mm, P < 0.0001; children without constipation: 32.6 vs 14.6 mm, P = 0.0026). The cut-off for the rectal diameter measured above the symphysis to identify fecal retention was 27 mm, with high sensitivity and specificity (95.5% and 94.1%, respectively).
  
  
  CONCLUSIONS
  Ultrasound rectal diameter measurement can be used to detect fecal retention in children.
authors.affiliation: Department of Pediatrics, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan.
authors.forename: Reiko
authors.initials: R
authors.lastname: Hatori
authors.affiliation: PAL Clinic, Isesaki, Gunma, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tomomasa
authors.affiliation: Department of Pediatrics, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Ishige
authors.affiliation: Department of Pediatrics, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan.
authors.forename: Maiko
authors.initials: M
authors.lastname: Tatsuki
authors.affiliation: Department of Pediatrics, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan.
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Arakawa
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003248:Constipation / Q000175:diagnosis / Q000000981:diagnostic imaging*; D051517:Digital Rectal Examination; D005244:Fecal Impaction / Q000175:diagnosis / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D012007:Rectum / Q000000981:diagnostic imaging* / Q000473:pathology; D012680:Sensitivity and Specificity; D014463:Ultrasonography
keywords: constipation; disimpaction; fecal retention; rectal diameter; ultrasonography