title: Can hiatal ballooning be determined by two-dimensional translabial ultrasound?
abstract: BACKGROUND
  Imaging of the levator hiatus, the largest potential hernial portal in the human body, requires axial plane imaging by ultrasound or magnetic resonance imaging. The aim of this study is to determine whether 2D translabial ultrasound may identify excessive hiatal distensibility by measuring the anteroposterior (AP) diameter of the hiatus. This may become clinically relevant for risk stratification of women prior to prolapse surgery.
  
  
  METHODS
  This is a retrospective analysis of 577 women seen at a tertiary urogynaecological unit between May 2008 and September 2010. All women underwent a standardised interview, clinical prolapse assessment (ICS POP-Q) and translabial ultrasound. The hiatal AP diameter was measured at rest, on Valsalva and during pelvic floor muscle contraction. All analyses were performed offline, blinded against clinical data.
  
  
  RESULTS
  There was a strong statistical relationship between reported prolapse symptoms/pelvic organ descent and hiatal AP diameter on Valsalva (P < 0.001 on chi-squared test for trend). A cut-off of 6 cm of the AP hiatal diameter on Valsalva yielded a specificity of 0.64 and a sensitivity of 0.7 for detecting significant prolapse on ultrasound.
  
  
  CONCLUSIONS
  Hiatal ballooning can be diagnosed with 2D translabial ultrasound. We propose that an AP hiatal diameter on Valsalva of up to 5.99 cm be regarded as normal, with 6-<6.5 cm defined as mild, 6.5-<7 cm as 'moderate', 7-<7.5 cm as 'marked' and 7.5 or more as 'severe' ballooning.
authors.affiliation: Sydney Medical School Nepean, University of Sydney, Nepean Hospital, Penrith, New South Wales, Australia.
authors.forename: Maylene
authors.initials: M
authors.lastname: Pineda
authors.forename: KaLai
authors.initials: K
authors.lastname: Shek
authors.forename: Vivien
authors.initials: V
authors.lastname: Wong
authors.forename: Hans Peter
authors.initials: HP
authors.lastname: Dietz
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D005260:Female; D006801:Humans; D008875:Middle Aged; D009119:Muscle Contraction; D017773:Pelvic Floor / Q000000981:diagnostic imaging* / Q000473:pathology; D056887:Pelvic Organ Prolapse / Q000000981:diagnostic imaging / Q000209:etiology*; D012372:ROC Curve; D012189:Retrospective Studies; D016037:Single-Blind Method; D014463:Ultrasonography; D014636:Valsalva Maneuver; D055815:Young Adult
keywords: female pelvic organ prolapse; levator ani; levator hiatus; magnetic resonance imaging; pelvic floor ultrasound