CoSy Lunch Seminar 22/10

Abstract: Osteoporosis is a common age-related disease characterized by reduced bone density and increased fracture-risk. Nearly 40 percent of women and 13 percent of men suffer one or more fragility fractures in their lifetime, and the fracture prevalence will further rise with continued increase in life-expectancy. Osteoporotic hip fractures reduce life expectancy by 20 percent and add an annual healthcare cost of nearly 19 billion dollars in the United States only. Early and accurate diagnosis of osteoporosis and assessment of fracture-risk is fundamental to handle the disease, and bone imaging plays an important role to accomplish this goal. Dual-energy X-ray absorptiometry (DXA) measured bone mineral density (BMD) is clinically used to characterize osteoporosis. It is known that BMD explains 60-70% of the variability in bone strength and fracture-risk, and the remaining variability comes from collective effects of other factors such as cortical and trabecular bone distribution, and their micro-structural basis. Accurate and robust measurement of effective cortical and trabecular bone microstructural features, associated with bone strength and fracture-risk, is of paramount clinical significance. State-of-the-art imaging modalities for bone microstructural assessment include magnetic resonance imaging (MRI), high-resolution peripheral quantitative computed tomography (HR-pQCT), flat-panel cone beam CT (CBCT), and whole-body multi-row detector CT (MDCT). Different research groups have applied various methods for characterization of bone microstructure related to cortical porosity and thickness, trabecular volume, network area, spacing, number, star volume measure, structure model index, connectivity number etc. Our research group has developed unique methods for in vivo clinical CT-based assessment of cortical porosity and trabecular plate-rod and longitudinal-transverse micro-architecture. This talk presents the principles and basis of these methods, experimental results evaluating their fidelity, generalizability, and impact on translational and clinical research studies.