title: Endoscopic ultrasound with double-balloon endoscopy for the diagnosis of inverted Meckel's diverticulum: a case report.
abstract: BACKGROUND
  Inverted Meckel's diverticulum has usually been misdiagnosed in the cases based on computed tomography images presented in the literature. The final diagnosis was made intra-operatively or by pathology reports after surgery. Despite this, preoperative diagnosis could be made successfully by using endoscopic ultrasound with double-balloon endoscopy prior to surgery.
  
  
  METHODS
  A 60-year-old Japanese woman with severe anemia complained of several episodes of black stool over the preceding 2 years. Abdominal computed tomography showed a 3.0-cm low-density tumor in the ileum, suggesting a diagnosis of intestinal lipoma. Examination of the tumor by endoscopic ultrasound with double-balloon endoscopy revealed a hypo-echoic layer corresponding to the muscularis propria, and a hyper-echoic layer corresponding to the fat tissue. These findings, which suggested that the tumor included areas outside the intestinal serosa, are not typical for a lipoma, despite the existence of a hyper-echoic layer corresponding to fatty tissue. We then considered a diagnosis of inverted Meckel's diverticulum.
  
  
  CONCLUSIONS
  Lipoma and inverted Meckel's diverticulum are difficult to differentially diagnose by computed tomography. Polypectomy is the preferred therapeutic approach when a lipoma is present; however, polypectomy in a patient with Meckel's diverticulum requires full-thickness resection. Situations where polypectomy is performed without preparing for full-thickness resection can be avoided by first making a precise diagnosis using double-balloon endoscopy and endoscopic ultrasound.
authors.affiliation: Department of Gastroenterology & Hepatology, Graduate School of Medicine, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan. araki.gast@tmd.ac.jp.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Araki
authors.forename: Kiichiro
authors.initials: K
authors.lastname: Tsuchiya
authors.forename: Shigeru
authors.initials: S
authors.lastname: Oshima
authors.forename: Eriko
authors.initials: E
authors.lastname: Okada
authors.forename: Shinji
authors.initials: S
authors.lastname: Suzuki
authors.forename: Junko Morio
authors.initials: JM
authors.lastname: Akiyama
authors.forename: Toshimitsu
authors.initials: T
authors.lastname: Fujii
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Okamoto
authors.forename: Mamoru
authors.initials: M
authors.lastname: Watanabe