The direct examination of three-dimensional bone architecture in vitro by computed tomography

Abstract

We describe a new method for the direct examination of three-dimensional bone structure in vitro based on high-resolution computed tomography (CT). Unlike clinical CT, a three-dimensional reconstruction array is created directly, rather than a series of two-dimensional slices. All structural indices commonly determined from two-dimensional histologic sections can be obtained nondestructively from a large number of slices in each of three orthogonal directions. This permits a comprehensive description of structural variation within a specimen and greatly facilitates the study of structural anisotropy. A measure of three-dimensional connectivity (Euler number/tissue volume) has been determined for the first time in human cancellous bone and shown to correlate with several two-dimensional histomorphometric indices. The method has the potential for overcoming many of the limitations of current approaches to the study of bone architecture at the microscopic level.

Ultrasound Simulation in the Distal Radius Using Clinical High-Resolution Peripheral-CT Images

“…However, another study (at the 1/3rd radius site) used 2D simulations that were validated through measurements on rods and tubes (Kaufman et al 2008b) and, thus, it is expected that the simulations presented here would also prove to be valid as well. We have also used 2D assessment of trabecular structure; this is necessitated of course by the 2D slices utilized but it should be noted that these 2D histomorphometric features are well correlated to the 3D structure and properties of bone (Dalle Carbonare et al 2005;Feldkamp et al 1989). …”

Pause Insertions During Cyclic In Vivo Loading Affect Bone Healing

“…Each scan included a phantom containing air, saline, and an SB-3 bone analog (1.18 g/cc) for calibration of image Hounsfield units to tissue mineral density in milligrams per centimeter. Reconstruction of the individual projections to CT volume data was accomplished with a modified Parker algorithm [15,25] with an isotropic voxel resolution of 24 lm.…”

High-Resolution CT for Small-Animal Imaging Research

“…Differently from clinical CT, where stacked 1D arrays of detection elements on a cylindrical surface are used, the majority of micro-CT systems to date employ digital flat-surface 2D detectors leading to a cone beam scanning geometry. Apart from a single case known in the literature of high-resolution CT reconstruction of a rat kidney from the digitization of multiple film radiographs (Kujoory et al, 1980), early prototype micro-CT systems employed x-ray image intensifiers read by charged coupled devices (CCDs) (Boone et al, 1993;Feldkamp et al, 1989;Holdsworth et al, 1993). Later in the mid-1990s, combined detection systems made up of scintillator screens coupled to CCDs via fiber-optic bundles, with various demagnifying ratios, became the standard for micro-CT imaging (Goertzen et al, 2004;Paulus et al, 2000).…”

“…Micro-CT has been used to investigate the structure and density of rodent bone since its very beginning (Feldkamp et al, 1989;Kinney et al, 1995), due to its high spatial resolution and high contrast in imaging mineralized tissues. In fact, the study of bone architecture and density drove the early developments of micro-CT systems (Ruegsegger et al, 1996).…”