Diffusion tensor imaging and magnetic resonance spectroscopy assessment of cancellous bone quality in femoral neck of healthy, osteopenic and osteoporotic subjects at 3T: Preliminary experience

Materials and methods: Forty postmenopausal women (mean age, 68.7 years; range 52-81 years), underwent a Dual-energy X-ray absorptiometry (DXA) examination in femoral neck, to be classified as healthy (n = 12), osteopenic (n = 14) and osteoporotic (n = 14) subjects. H-1-MRS and DTI (with b value = 2500 s/mm(2)) of femoral neck were obtained in each subject at 3T. The study protocol was approved by local Ethics Committee. MD, FA, FF and MD/FF, FA/FF were obtained and compared among the three bone-density groups.

We assessed the potential of diffusion tensor imaging (DTI) in combination with proton magnetic resonance spectroscopy (H-1-MRS), in cancellous bone quality evaluation of the femoral neck in postmenopausal women. Introduction: DTI allows for non-invasive microarchitectural characterization of heterogeneous tissue. In this work we hypothesized that DTI parameters mean diffusivity (MD) and fractional anisotropy (FA) of bone marrow water, can provide information about microstructural changes that occur with the development of osteoporosis disease. Because osteoporosis is associated with increased bone marrow fat content, which in principal can alter DTI parameters, the goal of this study was to examine the potential of MD and FA, in combination with bone marrow fat fraction (FF), to discriminate between healthy, osteopenic and osteoporotic subjects, classified according to DXA criteria.