title: US findings of adnexal torsion in children and adolescents: size really does matter.
abstract: BACKGROUND
  Adnexal torsion is rare, and symptoms are nonspecific. Clinicians often rely on US examinations to evaluate girls with abdominal or pelvic pain.
  
  
  OBJECTIVE
  To determine which sonographic findings can predict adnexal torsion by comparing pediatric and adolescent patients with surgically confirmed torsion (cases) to those without torsion (controls).
  
  
  METHODS
  Cases and controls were identified retrospectively by searching 7 years of medical record and radiology databases. An adnexal ratio was calculated as the volume of the affected adnexa divided by the volume of the unaffected adnexa.
  
  
  RESULTS
  We identified 61 menarchal subjects: 33 cases and 28 controls. Adnexal volume was larger in cases than in controls (185 vs. 37.8 ml, P < 0.001). A volume of >75 ml was more common in cases than in controls (64 vs. 15%, P < 0.001). No cases had an adnexal volume of <20 ml (P < 0.001). The adnexal ratio was larger in cases than in controls (16.1 vs. 6.7, P < 0.001). An adnexal ratio of >15 was seen in 40% of cases and in no controls (P = 0.08). Doppler US results were not predictive of torsion.
  
  
  CONCLUSIONS
  An adnexal volume of <20 ml is strong evidence against adnexal torsion in menarchal females. In this age group, the diagnosis of torsion cannot be established by US examination alone.
authors.affiliation: Cincinnati Children's Hospital Medical Center, Department of Radiology, University of Cincinnati School of Medicine, Cincinnati, OH 45229, USA. Leann.linam@cchmc.org
authors.forename: Leann E
authors.initials: LE
authors.lastname: Linam
authors.forename: Renuka
authors.initials: R
authors.lastname: Darolia
authors.forename: Lena N
authors.initials: LN
authors.lastname: Naffaa
authors.forename: Lesley L
authors.initials: LL
authors.lastname: Breech
authors.forename: Sara M
authors.initials: SM
authors.lastname: O'hara
authors.forename: Paula J
authors.initials: PJ
authors.lastname: Hillard
authors.forename: Jill S
authors.initials: JS
authors.lastname: Huppert
mesh_terms: D000291:Adnexal Diseases / Q000000981:diagnostic imaging*; D000293:Adolescent; D000328:Adult; D049628:Body Size; D002648:Child; D005260:Female; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014102:Torsion Abnormality / Q000000981:diagnostic imaging*; D014463:Ultrasonography / Q000379:methods*