title: Cone beam CT in assessment of tibial bone defect healing: an animal study.
abstract: OBJECTIVE
  To evaluate cone beam computed tomography (CBCT) for monitoring of tibial bone defect healing in comparison to histopathological findings.
  
  
  METHODS
  Circumscribed tibial bone defects were created in 16 mini-pigs and imaging of the tibia was performed on day 42 using a modern CBCT scanner with flat panel detector (PaX-Duo3D, Vatech, Korea). The extent of osseous consolidation including remaining calcium phosphate granules was measured quantitatively by a CBCT volumetry tool using commercially available software (Osirix Imaging software, Pixmeo, Geneva, Switzerland). Volumes of the entire defect (including all pixels), areas of osseous consolidation (density values >2350) and nonmineralized areas (density values <2350) of the defect were determined. The extent of bone regeneration was determined and correlated with the histomorphometrical reference standard. Independently, a visual semiquantitative CBCT-score was applied (4-point scale) to assess bone defect healing.
  
  
  RESULTS
  The extent of osseous consolidation in CBCT volumetry ranged from 14% to 92% (mean, 63.4 ± 17.6%). There was a significant positive correlation between histologically visible newly formed bone and the extent of bone regeneration on CBCT volumetry (r = 0.74-0.79, P < .001). The visual score matched with the volumetric results in 75% of the cases.
  
  
  CONCLUSIONS
  CBCT volumetry allows for reliable, noninvasive quantitative monitoring of bone defect healing and correlates significantly with histological findings. CBCT is a promising technique for imaging of peripheral bones suggesting further evaluation in clinical trials.
authors.affiliation: Department of Diagnostic and Interventional Radiology, University of Düsseldorf, Medical Faculty, Deutschland. Patric.Kroepil@med.uni-duesseldorf.de
authors.forename: Patric
authors.initials: P
authors.lastname: Kröpil
authors.forename: Ahmad R
authors.initials: AR
authors.lastname: Hakimi
authors.forename: Pascal
authors.initials: P
authors.lastname: Jungbluth
authors.forename: Carolin
authors.initials: C
authors.lastname: Riegger
authors.forename: Christian
authors.initials: C
authors.lastname: Rubbert
authors.forename: Falk
authors.initials: F
authors.lastname: Miese
authors.forename: Rotem S
authors.initials: RS
authors.lastname: Lanzman
authors.forename: Michael
authors.initials: M
authors.lastname: Wild
authors.forename: Alberto
authors.initials: A
authors.lastname: Schek
authors.forename: Axel
authors.initials: A
authors.lastname: Scherer
authors.forename: Joachim
authors.initials: J
authors.lastname: Windolf
authors.forename: Gerald
authors.initials: G
authors.lastname: Antoch
authors.forename: Juergen
authors.initials: J
authors.lastname: Becker
authors.forename: Mohssen
authors.initials: M
authors.lastname: Hakimi
mesh_terms: D000818:Animals; D054893:Cone-Beam Computed Tomography / Q000379:methods*; D017102:Fracture Healing / Q000502:physiology*; D013552:Swine; D013556:Swine, Miniature; D013978:Tibial Fractures / Q000000981:diagnostic imaging* / Q000503:physiopathology*