title: Anatomical and functional characteristics of the pelvic floor in nulliparous women submitted to three-dimensional endovaginal ultrasonography: case control study and evaluation of interobserver agreement.
abstract: OBJECTIVE
  To determine anatomical and functional pelvic floor measurements performed with three-dimensional (3-D) endovaginal ultrasonography in asymptomatic nulliparous women without dysfunctions detected in previous dynamic 3-D anorectal ultrasonography (echo defecography) and to demonstrate the interobserver reliability of these measurements.
  
  
  METHODS
  Asymptomatic nulliparous volunteers were submitted to echo defecography to identify dynamic dysfunctions, including anatomical (rectocele, intussusceptions, entero/sigmoidocele and perineal descent) and functional changes (non-relaxation or paradoxical contraction of the puborectalis muscle) in the posterior compartment and assessed with regard to the biometric index of levator hiatus, pubovisceral muscle thickness, urethral length, anorectal angle, anorectal junction position and bladder neck position with the 3-D endovaginal ultrasonography. All measurements were compared at rest and during the Valsalva maneuver, and perineal and bladder neck descent was determined. The level of interobserver agreement was evaluated for all measurements.
  
  
  RESULTS
  A total of 34 volunteers were assessed by echo defecography and by 3-D endovaginal ultrasonography. Out of these, 20 subjects met the inclusion criteria. The 14 excluded subjects were found to have posterior dynamic dysfunctions. During the Valsalva maneuver, the hiatal area was significantly larger, the urethra was significantly shorter and the anorectal angle was greater. Measurements at rest and during the Valsalva maneuver differed significantly with regard to anorectal junction and bladder neck position. The mean values for normal perineal descent and bladder neck descent were 0.6 cm and 0.5 cm above the symphysis pubis, respectively. The intraclass correlation coefficient ranged from 0.62-0.93.
  
  
  CONCLUSIONS
  Functional biometric indexes, normal perineal descent and bladder neck descent values were determined for young asymptomatic nulliparous women with the 3-D endovaginal ultrasonography. The method was found to be reliable to measure pelvic floor structures at rest and during Valsalva, and might therefore be suitable for identifying dysfunctions in symptomatic patients.
authors.affiliation: Anorectal Physiology and Pelvic Floor Unit, Hospital das Clínicas, Universidade Federal do Ceará, Fortaleza, CE, Brazil.
authors.forename: Sthela Maria
authors.initials: SM
authors.lastname: Murad-Regadas
authors.forename: Leonardo Robson Pinheiro Sobreira
authors.initials: LR
authors.lastname: Bezerra
authors.forename: Claudio Regis Sampaio
authors.initials: CR
authors.lastname: Silveira
authors.forename: Jacyara de Jesus Rosa
authors.initials: Jde J
authors.lastname: Pereira
authors.forename: Graziela Olivia da Silva
authors.initials: GO
authors.lastname: Fernandes
authors.forename: José Ananias
authors.initials: JA
authors.lastname: Vasconcelos Neto
authors.forename: Iris Daiana
authors.initials: ID
authors.lastname: Dealcanfreitas
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000706:statistics & numerical data; D015588:Observer Variation; D010298:Parity; D017773:Pelvic Floor / Q000033:anatomy & histology* / Q000000981:diagnostic imaging / Q000502:physiology*; D014463:Ultrasonography / Q000379:methods; D014621:Vagina; D055815:Young Adult