Three-dimensional quantitative CT of the proximal femur: relationship to vertebral trabecular bone density in postmenopausal women.

Abstract

Dual-photon absorptiometry (DPA) of the proximal femur cannot independently measure cortical and high-turnover cancellous bone. In this investigation, integrated cancellous, cortical, and total bone densities in the femoral neck and intertrochanteric region were measured bilaterally in 22 women aged 42-75 years. Contiguous section data were analyzed with two different protocols by means of three-dimensional histogram software. Single-section quantitative computed tomography (CT) was used to determine mean mineral equivalent values for vertebral cancellous bone from T-11 to L-3 in each woman. Significant correlation was found between cancellous bone density at the two sites, as well as between total femoral and vertebral measurements. Femoral cortical bone density was predicted less well by means of the vertebral cancellous data. Cortical, cancellous, and total proximal femoral density values tended to exhibit bilateral symmetry. Quantitative three-dimensional volumetric CT affords comprehensive evaluation of proximal femoral mineral status because of its capability for selective measurement of cortical, cancellous, and total bone density.

Changes in Cortical Bone Mineralization in the Developing Mandible: A Three-Dimensional Quantitative Computed Tomography Study

“…The cortical bone between these edges cannot be visualized and their internal remodeling and/or changes in mechanical quality cannot be determined. In contrast, applying QCT to evaluate mineralization within a three‐dimensional reconstruction provides a method to assess the mandible (7–9,21,22) …”

“…In contrast, applying QCT to evaluate mineralization within a three-dimensional reconstruction provides a method to assess the mandible. (7)(8)(9)21,22) To fully understand bone remodeling, the ideal methods should include structural information (i.e., size, shapes, architecture, and connectivity) and characteristic properties (i.e., density, hardness, and elasticity) that are applied in a three-dimensional reconstruction. We attempted this approach in our first paper evaluating QCT with a specialized phantom.…”

“…Comprehensive evaluation of bone relies on several properties that include assessing its architecture as well as its mineralization (3–6) . More recent techniques with computed tomography (CT) have provided a method to quantify the bone mineralization defined by quantitative computed tomography (QCT) and to evaluate this in a three‐dimensional reconstruction (7–9) . Computer programs provide an accurate method to reconstruct the entire mandible from the computer‐based images.…”

“…(3)(4)(5)(6) More recent techniques with computed tomography (CT) have provided a method to quantify the bone mineralization defined by quantitative computed tomography (QCT) and to evaluate this in a three-dimensional reconstruction. (7)(8)(9) Computer programs provide an accurate method to reconstruct the entire mandible from the computer-based images. This three-dimensional reconstruc-tion has extended to developing finite element models (FEM) that predict stresses within the mandible based on computer models that include muscle function.…”

Quantitative computed tomography at the axial and peripheral skeleton

“…Several researchers have examined automated algorithms to accomplish this. Heitz et al [42] has developed an femoral-neck-fixed coordinate system operated in conjunction with a second-derivative-based edge detection technique to determine VOIs (volumes of interest), while Sartoris et al [43] and Bhasin et al [44] have employed threshold-driven edge detection methods to isolate the entire compartment of trabecular bone in the proximal femur. Recently, Lang et al [45] have presented an approach to semi-automatically define integral and trabecular VOIs in the femoral neck and intertrochanteric sub-regions ( Fig.…”