Cortical measurements of the tibia from high resolution peripheral quantitative computed tomography images: a comparison with synchrotron radiation micro-computed tomography

Agnès Ostertag; Françoise Peyrin; Sylvie Fernandez; Jean Denis Laredo; Marie Christine de Vernejoul; Christine Chappard

doi:10.1016/j.bone.2014.02.009

Cortical measurements of the tibia from high resolution peripheral quantitative computed tomography images: a comparison with synchrotron radiation micro-computed tomography

Bone. 2014 Jun:63:7-14. doi: 10.1016/j.bone.2014.02.009. Epub 2014 Feb 26.

Authors

Agnès Ostertag¹, Françoise Peyrin², Sylvie Fernandez¹, Jean Denis Laredo³, Marie Christine de Vernejoul¹, Christine Chappard⁴

Affiliations

¹ INSERM 606 University Paris Diderot, PRES Sorbonne Paris Cité, 75010 Paris France.
² CREATIS, INSERM U1044, CNRS 5220, Université de Lyon, 69621 Villeurbanne Cedex, France; ESRF, X-ray Imaging Group, 38043 Grenoble Cedex, France.
³ B2OA, UMR CNRS7052, University Denis Diderot, PRES Sorbonne Paris Cité, 75010 Paris, France.
⁴ B2OA, UMR CNRS7052, University Denis Diderot, PRES Sorbonne Paris Cité, 75010 Paris, France. Electronic address: christine.chappard@inserm.fr.

PMID: 24582804
DOI: 10.1016/j.bone.2014.02.009

Abstract

High resolution-peripheral quantitative computed tomography (HR-pQCT) measurements are carried out in clinical research protocols to analyze cortical bone. Micro-computed tomography (micro-CT) is a standard tool for ex vivo examination of bone in 3D. The aim of this work was to evaluate cortical measurements derived from HR-pQCT images compared to those from synchrotron radiation (SR) micro-CT in a distal position (4.2 cm from the distal pilon). Twenty-nine tibia specimens were scanned with HR-pQCT using protocols provided by the manufacturer. The standard measured outcomes included volumetric bone density (gHA/cm(3)) of the cortical region (Dcomp), and the cortical thickness (Ct.Th, mm). New features, such as cortical porosity (Ct.Po) and mean pore diameter (Ct.Po.Dm), were measured by an auto-contouring process. All tibias were harvested from the posterior region and imaged with SR micro-CT (voxel size=7.5 μm). The cortical thickness, (Ct.Thmicro-CT), porosity (PoV/TV), pore diameter, pore spacing, pore number, and degree of mineralization of bone (DMB) were obtained for SR micro-CT images. For standard measurements on HR-pQCT images, site matched analyses with micro-CT were completed to obtain Dcomplocal and Ct.Thlocal. Dcomp was highly correlated to PoV/TV (r=-0.84, p<10(-4)) but not to DMB. Dcomplocal was correlated to PoV/TV (r=-0.72, p<10(-4)) and to DMB (r=0.40, p>0.05). Ct.Thlocal and Ct.Thmicro-CT were moderately correlated (r=0.53, p<0.01). Ct.Th and Ct.Po results from the autocontouring process are influenced by the level of trabecularization of the cortical bone and need manual correction of the endosteal contour. Distal tibia is a reliable region to study cortical bone with Dcomp as the best parameter because it reflects both the micro-porosity (Havers canals) and macro-porosity (resorption lacunae) of the cortical bone.

Keywords: Cortical bone; High resolution peripheral quantitative computed tomography; Synchrotron radiation micro-computed tomography; X-ray.

MeSH terms

Aged
Aged, 80 and over
Bone Density / physiology
Female
Humans
Male
Synchrotrons*
Tibia / diagnostic imaging*
X-Ray Microtomography / methods*