title: Changes in the Distance Between the Distal Rectal Pouch and Perineum From the Birth Day to the Next Day in Neonates With an Imperforate Anus.
abstract: OBJECTIVE
  To evaluate changes in the distance between the distal rectal pouch and the perineum (pouch-perineum distance) from the birth day to the next day and to determine which day is better for diagnosis of a low-type imperforate anus in neonates.
  
  
  METHODS
  We reviewed medical records at our hospital from May 2003 to August 2015 and identified 9 neonates with a radiographically and surgically proven low-type imperforate anus and 9 with high/intermediate types of imperforate anus who had undergone sonography on both the birth day and the next day before the first surgical treatment. The sonograms were reviewed to measure the pouch-perineum distance at both examinations. The Wilcoxon signed rank sum test and a receiver operating characteristic curve analysis were used for the statistical analyses.
  
  
  RESULTS
  The pouch-perineum distance on the next day (mean ± SD, 9.37 ± 4.89 mm; range, 2.1-20.9 mm) was significantly shorter than on the birth day (15.75 ± 6.67 mm; range, 8.1-37.2 mm; P = .001). The receiver operating characteristic analysis showed significantly better diagnostic performance (P < .001) of the pouch-perineum distance on the next day (area under the curve, 0.864) versus the birth day (0.420) for the low-type imperforate anus.
  
  
  CONCLUSIONS
  The pouch-perineum distance was shorter on the next day than on the birth day, and the diagnostic performance of the pouch-perineum distance on the next day was significantly superior to that on the birth day for the diagnosis of a low-type imperforate anus. We recommend sonography on the next day in neonates with an imperforate anus when possible.
authors.affiliation: Department of Radiology, Saitama Children's Medical Center, Saitama, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Hosokawa
authors.affiliation: Department of Diagnostic Radiology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Yoshitake
authors.initials: Y
authors.lastname: Yamada
authors.affiliation: Department of Radiology, Saitama Children's Medical Center, Saitama, Japan.
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Sato
authors.affiliation: Department of Radiology, Saitama Children's Medical Center, Saitama, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Tanami
authors.affiliation: Department of Surgery, Saitama Children's Medical Center, Saitama, Japan.
authors.forename: Yujiro
authors.initials: Y
authors.lastname: Tanaka
authors.affiliation: Department of Surgery, Saitama Children's Medical Center, Saitama, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawashima
authors.affiliation: Department of Radiology, Saitama Children's Medical Center, Saitama, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Oguma
mesh_terms: D001006:Anus, Imperforate / Q000000981:diagnostic imaging*; D001837:Body Weights and Measures / Q000379:methods*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D010502:Perineum / Q000000981:diagnostic imaging*; D012007:Rectum / Q000000981:diagnostic imaging*; D012189:Retrospective Studies; D014463:Ultrasonography / Q000379:methods*
keywords: imperforate anus; infant; neonate; pediatric ultrasound; sensitivity; sonography; specificity