title: Three-dimensional ultrasonography versus two-dimensional ultrasonography for the diagnosis of intrauterine device malposition.
abstract: OBJECTIVE
  To compare the diagnostic accuracy of two-dimensional (2D) versus three-dimensional (3D) ultrasonography for the diagnosis of intrauterine device (IUD) malposition.
  
  
  METHODS
  In a prospective study, women with a history of failed IUD removal and/or ultrasonography results indicating malposition were recruited at a center in Hangzhou, China, between March 1, 2009, and September 30, 2011. All patients underwent 2D and 3D ultrasonography. Hysteroscopy, laparoscopy, or laparotomy was carried out to remove the IUDs and was considered the gold standard for diagnosing malposition.
  
  
  RESULTS
  Among 130 participants, 128 (98.5%) were diagnosed with IUD malposition by hysteroscopy, laparoscopy, or laparotomy. Malposition had been correctly identified with 2D ultrasonography in 83 (64.8%) cases, and with 3D ultrasonography in 107 (83.6%) cases. The diagnostic accuracy of 3D ultrasonography was significantly better than was that of 2D ultrasonography (P<0.001).
  
  
  CONCLUSIONS
  The use of 2D ultrasonography is recommended for the follow-up of women who use IUDs as a contraceptive method. However, 3D ultrasonography should be used when malposition is suspected.
authors.affiliation: The Fourth Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, China.
authors.forename: Xiu-ying
authors.initials: XY
authors.lastname: Chen
authors.affiliation: Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
authors.forename: Qing-yun
authors.initials: QY
authors.lastname: Guo
authors.affiliation: Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Wang
authors.affiliation: Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, China. Electronic address: fbhuanglili@163.com.
authors.forename: Li-li
authors.initials: LL
authors.lastname: Huang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002681:China; D020878:Device Removal; D005260:Female; D006801:Humans; D015907:Hysteroscopy / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D007434:Intrauterine Devices; D010535:Laparoscopy / Q000379:methods; D007813:Laparotomy / Q000379:methods; D008875:Middle Aged; D011446:Prospective Studies; D014463:Ultrasonography / Q000379:methods*; D055815:Young Adult
keywords: Diagnostic accuracy; Intrauterine device; Malposition; Three-dimensional ultrasonography; Two-dimensional ultrasonography