title: Volumetric analysis of corticocancellous bones using CT data.
abstract: OBJECTIVE
  To present a method for an automated volumetric analysis of corticocancellous bones such as the superior pubic ramus using CT data and to assess the reliability of this method.
  
  
  METHODS
  Computed tomography scans of a consecutive series of 250 patients were analyzed. A Hounsfield unit (HU) thresholding-based reconstruction technique ("Vessel Tracking," GE Healthcare) was used. A contiguous space of cancellous bone with similar HU values between the starting and end points was automatically identified as the region of interest. The identification was based upon the density gradient to the adjacent cortical bone. The starting point was defined as the middle of the parasymphyseal corticocancellous transition zone on the axial slice showing the parasymphyseal superior pubic ramus in its maximum anteroposterior width. The end point was defined as the middle of the periarticular corticocancellous transition zone on the axial slice showing the quadrilateral plate as a thin cortical plate. The following parameters were automatically obtained on both sides: length of the center line, volume of the superior pubic ramus between the starting point and end point, minimum, maximum and mean diameter perpendicular to the center line, and mean cross-sectional area perpendicular to the center line.
  
  
  RESULTS
  An automated analysis without manual adjustments was successful in 207 patients (82.8%). The center line showed a significantly greater length in female patients (67.6 mm vs 65.0 mm). The volume was greater in male patients (21.8 cm(3) vs 19.4 cm(3)). The intersite reliability was high with a mean difference between the left and right sides of between 0.1% (cross-sectional area) and 2.3% (volume).
  
  
  CONCLUSIONS
  The method presented allows for an automated volumetric analysis of a corticocancellous bone using CT data. The method is intended to provide preoperative information for the use of intramedullary devices in fracture fixation and percutaneous cement augmentation techniques.
authors.affiliation: Department of Trauma Surgery and Sports Medicine, Medical University Innsbruck, Innsbruck, Austria. Dietmar@Krappinger.eu
authors.forename: Dietmar
authors.initials: D
authors.lastname: Krappinger
authors.forename: Astrid
authors.initials: A
authors.lastname: von Linde
authors.forename: Ralf
authors.initials: R
authors.lastname: Rosenberger
authors.forename: Bernhard
authors.initials: B
authors.lastname: Glodny
authors.forename: Michael
authors.initials: M
authors.lastname: Blauth
authors.forename: Christian
authors.initials: C
authors.lastname: Niederwanger
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D054893:Cone-Beam Computed Tomography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011630:Pubic Bone / Q000000981:diagnostic imaging*; D011856:Radiographic Image Enhancement / Q000379:methods*; D012016:Reference Values; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed