Bone Marrow Imaging by Third-generation Dual-source Dual-energy CT Using Virtual Noncalcium Technique for Assessment of Diffuse Infiltrative Lesions of Multiple Myeloma.

Objective To evaluate the value of bone marrow imaging by third-generation dual-source dual-energy CT(DSDECT) using virtual noncalcium(VNCa) technique for the assessment of diffuse infiltrative lesions of multiple myeloma(MM). Methods From December 2015 to June 2016,31 patients with plasma disorders at our center were prospectively recruited and received whole-body imaging with third-generation DSDECT and MRI. CT numbers of vertebrae were measured on VNCa images as well as regular CT images. Correlation between VNCa CT numbers and MRI signal intensities of the vertebrae was evaluated. The diagnostic ability of VNCa for MM infiltrative lesions was assessed by ROC analysis,using MRI as the reference standard. Results The mean VNCa CT numbers of vertebrae with MM diffuse infiltration (n=62) were (-13.27±18.96)HU,which were significantly higher than those of non-infiltrated vertebrae[(-63.31±26.75)HU,(n=117)] (Z=-9.731,P=0.000). VNCa CT numbers of vertebrae were negatively correlated with T1WI signal intensity normalized by non-degenerative vertebral discs (r=-0.592,P=0.000). ROC analysis showed the area under the curve of VNCa for the diagnosis of infiltrative lesions was 0.943. With the cut-off value of-37 HU,the sensitivity and specificity of VNCa were 90.32% and 87.18%,respectively. Conclusion Bone marrow imaging by third-generation DSDECT using VNCa technique is a valuable tool for assessing diffuse infiltrative lesions of MM.