Application of Dual-Energy Spectral Computed Tomography in Bone Mineral Density Measurement: Phantom and Clinical Research

Introduction: Early detection and treatment of osteoporosis through bone mineral density (BMD) measurement could aid in the prevention of osteoporosis-related fractures. We aimed to assess the parameter of dual-energy spectral CT (DesCT) consistency with BMD determination using quantitative computed tomography (QCT), thereby establishing a basis for further DesCT application for BMD determination. Methods: We subjected the European spine phantom, which contains three vertebral bodies (V1, V2, and V3), to DesCT with different radiation doses. The basis material pairs were hydroxyapatite (water), calcium (water), and hydroxyapatite (fat). Additionally, the medical records of 152 patients who underwent QCT and DesCT for chest scans in a two-month period were reviewed to measure BMD values. Results: No significant differences were found in the basis pair values of the V1, V2, or V3 vertebrae under different radiation doses in the phantom; in particular, the hydroxyapatite (water), hydroxyapatite (fat), relative error values of V1, V2, and V3 under different radiation doses were not significantly different (all p > 0.05). For patients, the hydroxyapatite (water), hydroxyapatite (fat), and hydroxyapatite (average) values measured by DesCT had a significant correlation with BMD measured by QCT Among 242 vertebrae (152 T12 and 90 L1 vertebrae), there was no significant difference between the BMD measured by QCT and the HAP (average) measured by DesCT (p = 0.071). The interclass correlation coefficient (ICC) value was 0.925 between the HAP (average) and HAP (average) with DesCT and BMD measured by QCT (p < 0.001). Bland-Altman diagram indicated that both measurements were in good agreement. Discussion: We showed that BMD values measured by DesCT were stable and repeatable under different radiation doses. DesCT and QCT measurements of human BMD were highly correlated. Thus, DesCT-based BMD assessment of the spine in a clinical setting could be considered feasible.