Objective: We aimed to assess accuracy and precision of quantitative computed tomography (QCT) and phantomless in thoracic bone mineral density (BMD) assessment using coronary artery calcium scan (CACS).
Methods: A total of 513 subjects underwent CACS with a calibration phantom. The thoracic spine BMD and concentration of calcium hydroxyapatite in phantom rods, as well CT Hounsfield unit of both, were measured. The thoracic BMD and phantom-rods calcium concentration were obtained using phantomless. The accuracy and precision error of QCT and phantomless were compared.
Results: The mean biases from true calcium concentration of phantom rods were 2.9% and 3.8% for the QCT and phantomless, respectively (P < 0.001). The biases of thoracic BMD from QCT by phantomless were 3.8% with a similar precision error in both methods.
Conclusions: The thoracic BMD can be assessed accurately and precisely using QCT and phantomless with a routine CACS.