title: Internal hernia through a peritoneal defect in the pouch of Douglas: Report of a case.
abstract: BACKGROUND
  Internal hernia is a rare entity which can cause intestinal obstruction. The most common type of internal hernia is the paraduodenal hernia which accounts for 53% of cases, and the internal hernia within the pelvis account for 7%. Perineal hernia, which is classified as pelvic hernia, usually occurs due to weakening of the pelvic floor musculature and thus, should be distinguished from the internal hernia caused by peritoneal defects in the pelvic cavity.
  
  
  METHODS
  We present a case of 28-year-old female who presented intestinal obstruction. Conservative therapies failed and she required emergency laparotomy. The operative findings revealed a peritoneal defect of 2cm in diameter in the pouch of Douglas, through which the ileum was incarcerated and strangulated. The incarcerated bowel was reduced, and the intestinal color quickly returned to normal. Therefore a primary closure of the peritoneal defect was performed and the postoperative course was uneventful.
  
  
  CONCLUSIONS
  A PubMed search for the case of internal hernia through a defect in the pouch of Douglas revealed only three, making this an extremely rare condition.
  
  
  CONCLUSIONS
  Because of rarity of this hernia, the etiology is unknown. However, our patient is a young female with no history of pregnancy, abdominal surgery, or trauma, therefore the cause of the peritoneal defect is considered congenital.
authors.affiliation: Department of Surgery, Jikei University School of Medicine, Daisan Hospital, 4-11-1, Izumihoncho, Komae-city, Tokyo 201-8601, Japan. Electronic address: katsuhito-s@jikei.ac.jp.
authors.forename: Katsuhito
authors.initials: K
authors.lastname: Suwa
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Yamagata
authors.forename: Ken
authors.initials: K
authors.lastname: Hanyu
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Suzuki
authors.forename: Tomoyoshi
authors.initials: T
authors.lastname: Okamoto
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Yanaga