Bone Marrow Perfusion Study Based On Dynamic Contrast-enhanced Magnetic Resonance Imaging

Osteoporosis is a systemic bone disease characterized by reduced bone mass,damaged bone microstructure, thinned bone, increased osteopsathyrosis and thatpredisposes to fracture. Osteoporosis is a common metabolic bone disorder with a highincidence in elderly and its consequences have become to be one of the most increasingconcerns in the world. In patients with osteoporosis, postmenopausal women aredominant, and the disease will be more common with the extension of human life. Thehuge elderly population and high incidence of osteoporosis in elderly make Chinabearing a heavier national financial burden and the fracture and other diseases caused byosteoporosis have become a serious public health problem.Osteoporosis is a kind ofpathologyparticipated by multiple factors and affects allbone, however, the actual pathophysiology of osteoporosis remains unclear. On thebasis of flow effect,the change of tissue blood perfusion can be detected by MRperfusion imaging methods to observe the microscopic movement of molecules.Changes in the blood circulation caused by vascular disease may be related to bonemineral density, but there is still no related research results show the physiologicalmechanism of this relationship. These need to rely on the further study of the bonemarrow infusion to reveal, thus dynamic contrastenhanced magnetic resonance imaging(DCE-MRI) is good method for researching on bone marrow perfusion. Arterial inputfunction(AIF) was a very important factor to perfusion parameters and has become to beone focus in the field of perfusion, which was unstable and need higher time resolution.The objective of this study is to improve or eliminate the effect of AIF to investigatethe relationship between blood circulation and osteoporosis by researching on bonemarrow perfusion and bone mineral density (BMD. This study utilized DCE-MRI,improved the AIF algorithm on the base ofTofts model toinvestigate bone marrowperfusion of vertebral body and extract reliable perfusion parameters.Furthermore, thisstudy established a muscle-based model to investigate bone marrow perfusion ofvertebral body, whichselect the erector spinae muscle to replace the AIF so that thismodel was independent of AIF. The subjects were classified into three groups accordingto the T-score derived from the BMD, including normal subjects, the osteopenia and osteoporotic subjects. Analysis of variance method (ANOVA) was employed to evaluatedifferences in pharmacokinetic parameters among three groups with different BMD.The study found that perfusion parameters showed a significant difference amonggroups with different BMD, which indicated that bone marrow perfusion is related toBMD. Besides, muscle-based model provided important information about muscleperfusion. The results showed that there is a link between bone microcirculation andBMD. The change of bone marrow blood supply could be one pathogenic mechanism ofosteoporosis.