title: Influence of 3D QCT scan protocol on the QCT-based finite element models of human vertebral cancellous bone.
abstract: Quantitative computed tomography (QCT)-based finite element (FE) models provide a better prediction of vertebral strength than dual-energy X-ray absorptiometry. However, FE models are often created from datasets acquired at different CT scan protocols and it is unclear whether this influences the FE results. The aim of this paper was to investigate whether there was an effect of the CT scan protocol on the FE models. 12 human thoracolumbar vertebrae were scanned on top of a calcium hydroxyapatite calibration phantom using a standard QCT scan protocol - 120kV, 100mAs (PA); and a low dose protocol - 90kV, 150mAs (PB). FE cancellous models with cuboid volume of interest and inhomogeneous nonlinear bone properties were created. Axial compression was simulated. The apparent BMD, modulus and yield strength showed significant differences between the two scan protocols. The apparent BMD, the modulus and yield strength between the two groups were highly linearly correlated. This paper indicated that the FE models created from image datasets acquired at different X-ray tube voltage settings would give significantly different results and this effect could be possibly corrected using a linear correction approach.
authors.affiliation: Institute of Biomechanics, TUHH Hamburg University of Technology, Germany. Electronic address: yongtao.lu@tuhh.de.
authors.forename: Yongtao
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Institute of Medical Physics, University of Erlangen, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Engelke
authors.affiliation: Department of Legal Medicine, UKE University Medical Center Hamburg-Eppendorf, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Püschel
authors.affiliation: Institute of Biomechanics, TUHH Hamburg University of Technology, Germany.
authors.forename: Michael M
authors.initials: MM
authors.lastname: Morlock
authors.affiliation: Institute of Biomechanics, TUHH Hamburg University of Technology, Germany.
authors.forename: Gerd
authors.initials: G
authors.lastname: Huber
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015519:Bone Density; D002138:Calibration; D019245:Compressive Strength; D003198:Computer Simulation; D017886:Durapatite; D055119:Elastic Modulus; D005260:Female; D020342:Finite Element Analysis; D006801:Humans; D016014:Linear Models; D008954:Models, Biological; D017711:Nonlinear Dynamics; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D013904:Thoracic Vertebrae / Q000000981:diagnostic imaging* / Q000502:physiology*; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D017886:Durapatite
keywords: Bone mineral density; Finite element model; Material mapping; QCT; Scan protocol; Spine