title: Levator ani subtended volume: a novel parameter to evaluate levator ani muscle laxity in pelvic organ prolapse.
abstract: OBJECTIVE
  We describe a new parameter based on magnetic resonance 3-dimensional (3D) reconstructions proposed to evaluate levator ani muscle (LAM) laxity in women with pelvic organ prolapse (POP).
  
  
  METHODS
  This is an institutional review board-approved, retrospective chart review of 35 women with POP, stages I-IV. The 3D Slicer software package was used to perform 2-dimensional and 3D measurements and the levator ani subtended volume (LASV) was described. Basically, the LASV represents the volume contained by LAM between 2 planes, which coincides with pubococcygeal line and H line. Correlations among measurements, ordinal POP stages, POP Quantification (POPQ) individual measurements, and validated questionnaires were performed.
  
  
  RESULTS
  The LASV differentiated major (III and IV) from minor (I and II) POPQ stages, which positively correlated to POP stages and POPQ individual measurements.
  
  
  CONCLUSIONS
  The LASV is a promising parameter to evaluate the LAM laxity.
authors.affiliation: Division of Female Pelvic Medicine and Reconstructive Surgery, Department of Obstetrics and Gynecology, University of South Florida College of Medicine, Tampa, FL 33606, USA. aantunesrj@yahoo.com.br
authors.forename: Antonio Antunes
authors.initials: AA
authors.lastname: Rodrigues
authors.forename: Renee
authors.initials: R
authors.lastname: Bassaly
authors.forename: Mona
authors.initials: M
authors.lastname: McCullough
authors.forename: H Leigh
authors.initials: HL
authors.lastname: Terwilliger
authors.forename: Stuart
authors.initials: S
authors.lastname: Hart
authors.forename: Katheryne
authors.initials: K
authors.lastname: Downes
authors.forename: Lennox
authors.initials: L
authors.lastname: Hoyte
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008875:Middle Aged; D053580:Muscle Strength / Q000502:physiology*; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000503:physiopathology; D017773:Pelvic Floor / Q000033:anatomy & histology / Q000503:physiopathology*; D056887:Pelvic Organ Prolapse / Q000503:physiopathology*; D012189:Retrospective Studies; D012984:Software; D055815:Young Adult