title: High resolution magnetic resonance imaging of urethral anatomy in continent nulliparous pregnant women.
abstract: BACKGROUND
  To quantify the distribution of morphologic appearances of urethral anatomy and measure variables of urethral sphincter anatomy in continent, nulliparous, pregnant women by high resolution magnetic resonance imaging (MRI).
  
  
  METHODS
  We studied fifteen women during their first pregnancy. We defined and quantified bladder neck and urethral morphology on axial and sagittal MR images from healthy, continent women.
  
  
  RESULTS
  The mean (±standard deviation) total transverse urethral diameter, anterior-posterior diameter, unilateral striated sphincter muscle thickness, and striated sphincter length were 15±2 mm (range: 12-19 mm), 15±2 mm (range: 11-20 mm), 2±1 mm (range: 1-4 mm), and 13±3 mm (range: 9-18 mm) respectively. The mean (±standard deviation) total urethral length on sagittal scans was 22±3 mm (range: 17.6-26.4 mm).
  
  
  CONCLUSIONS
  Advances in MR technique combined with anatomical and histological findings will provide an insight to understand how changes in urethral anatomy might affect the continence mechanisms in pregnant and non-pregnant, continent or incontinent individuals.
authors.affiliation: Hospital of the Divine Saviour, Department of Obstetrics and Gynecology, and Medical University of Vienna, Center of Anatomy and Cell Biology, Vienna, Austria. oliver.preyer@gmail.com
authors.forename: Oliver
authors.initials: O
authors.lastname: Preyer
authors.forename: Peter C
authors.initials: PC
authors.lastname: Brugger
authors.forename: Thomas
authors.initials: T
authors.lastname: Laml
authors.forename: Engelbert
authors.initials: E
authors.lastname: Hanzal
authors.forename: Daniela
authors.initials: D
authors.lastname: Prayer
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Umek
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D011247:Pregnancy; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014521:Urethra / Q000033:anatomy & histology*; D055815:Young Adult