Bone marrow perfusion of females with varied bone mineral density: A study by muscle-based model

The purpose of this study was to establish a new pharmacokinetic model to investigate bone marrow and muscle perfusion without using arterial input function. Based on the reference region model, erector spinae muscle around the vertebral body was selected as the reference region. A muscle-based model was established for erector spinae muscle perfusion with a personalized algorithm. Seventy-six female subjects (age 72.5±3.4 yrs) were recruited in this study and classified into three groups (normal, osteopenia, and osteoporosis) according to the T-score. Bone mineral density was measured by dual-energy X-ray absorptiometry. Quantitative parameters were extracted from the pharmacokinetic model, K^trans,TOI (contrast agent extravasation rate constants for blood perfusion of the tissue of interest) showed a significant reduction in subjects with lower bone mineral density, which were consistent with previous studies. However, muscle perfusion parameters remained unchanged among different groups. The results indicated that muscle-based model was stable for bone marrow perfusion modeling. Meanwhile, the maintained muscle perfusion indicated that the decreased perfusion in the bone marrow happened in the bone itself but not in the supply arteries.