Reproducibility of MR Perfusion and 1H Spectroscopy of Bone Marrow

Purpose: To determine the reproducibility of proton (H-1) magnetic resonance (MR) spectroscopy and dynamic contrast-enhanced MR imaging in a clinical setting for the assessment of marrow fat fraction and marrow perfusion in longitudinal studies. Materials and Methods: In all, 36 subjects (17 females, 19 males, mean age 72.9 +/ 2.9 years) who underwent MR spectroscopy and/or dynamic contrast-enhanced perfusion imaging of the proximal femur were asked to return after I week for a repeat MR examination. Results: Reproducibility of 1H MR spectroscopy in all bone areas tested was high, ranging from 0.78-0.85, with the highest reproducibility being in the femoral head and lowest in the femoral neck. Reproducibility of paired perfusion measurements ranged from 0.59 (enhancement slope femoral head) to 0.98 (enhancement maximum acetabulum). Overall reproducibility of H-1 MR spectroscopy and dynamic contrast-enhanced imaging tended to be best in areas with the highest inherent fat fraction or perfusion. Conclusion: Reproducibility of H-1 MR spectroscopy or perfusion imaging is sufficiently high to warrant these techniques being applied to the longitudinal study of bone diseases.