The Application Value Of The Third-generation Dual-source CT In The Differential Diagnosis Of Vertebral Osteolytic Metastases And Vertebral Hemangiomas

Objective: To explore the application value of virtual noncalcium(VNCa)and electron density/effective atomic number(Rho/Z)of the third-generation dual-source CT(DSCT)in the differential diagnosis of vertebral osteolytic metastases and vertebral hemangiomas.Methods: This prospective study has been reviewed by the medical ethics committee of our hospital,and all patients have signed written informed consent.A total of 414 vertebral bodies were collected from 45 patients with vertebral osteolytic metastases and vertebral hemangiomas diagnosed by MRI from May 2019 to December 2019.Among them,The vertebrolytic metastatic tumor group included 23 patients with 236 vertebrae and 26 lesions.Vertebral hemangioma group included 22 patients with 178 vertebrae and 25 lesions.Using MRI diagnosis as the reference standard,assuming that the bone marrow density of the vertebral hemangiomas on the dual-energy VNCa image are displayed as a limited blue color with a clear border,two physicians visually evaluated all patients with vertebral hemangiomas on a VNCa color-coded images to determine the presence of abnormal bone marrow attenuation,Vertebral hemangiomas were evaluated by two other physicians on weighted-average CT images,Finally,all vertebral bodies(including vertebral osteolytic metastases,vertebral hemangiomas,normal vertebral bodies)were measured and recorded by the 1 physician,and the VNCa CT value,Rho value,Z value,and weighted-average CT value were recorded,and compared the differences of each quantitative parameter among groups.Receiver operating characteristic curve(ROC)was used to evaluate the efficacy of quantitative parameters in the differential diagnosis of vertebral osteolytic metastases and vertebral hemangiomas.Results: In 178 vertebrae in the vertebral hemangioma group,MRI diagnosed 25 vertebral hemangiomas,and 2 physicians respectively diagnosed 28 and 28 vertebral hemangiomas on VNCa images.The consistency of subjective evaluation was high(Kappa = 0.695).The other 2physicians diagnosed 30 and 31 vertebral hemangiomas respectively on weighted-average CT images,with high consistency in subjective evaluation(Kappa = 0.687).Using MRI as the reference standard,the sensitivity,specificity,positive predictive value,negative predictive value and accuracy of VNCa images subjective evaluation in the diagnosis of vertebral hemangiomas were 84.0%,96.7%,80.7%,97.4% and 94.9%,respectively,The sensitivity,specificity,positive predictive value,negative predictive value and accuracy of weighted-average CT images subjective evaluation in diagnosis of vertebral hemangiomas were 80.0%,95.4%,74.1%,96.7%and 93.3%,respectively.There were statistically significant differences in quantitative DECT parameters(VNCa,Rho,Z)and weighted-average CT value among the vertebral osteolytic metastases group,vertebral hemangiomas group and normal vertebral bodies group(all P < 0.05).Among them,DECT parameters VNCa and Rho were the most effective in differentiating vertebral osteolytic metastases from vertebral hemangiomas,and there was no statistical difference in AUC between the two(P > 0.05).Pair comparison between groups showed statistically significant differences in VNCa,Rho and Z of DECT parameters(P < 0.05).The weighted-average CT value of the vertebral hemangiomas group were compared with those of the vertebral osteolytic metastases group and the normal vertebral bodies group,and the differences in groups were statistically significant(P < 0.05).There was no statistically significant difference in weighted-average CT value between the vertebral osteolytic metastases group and the normal vertebral bodies group(P > 0.05).The VNCa CT value,weighted-average CT value,and Rho value of the vertebral osteolytic metastases group was higher than those of the vertebral hemangiomas group,while Z was lower than that of the vertebral hemangiomas group.The cut-off value of VNCa,Rho,Z,and weighted-average CT value for differentiating vertebral osteolytic metastases from vertebral hemangiomas were-32.8HU,35.8HU,8.0,51.6HU,and AUC were 0.963,0.954,0.915,0.826,respectively.Conclusion:1 Dual-source CT quantitative analysis of VNCa CT value,Rho value,Z value and weighted-average CT value is valuable for the differential diagnosis of vertebral osteolytic metastases and vertebral hemangiomas,especially VNCa and Rho parameters.2 Dual-energy VNCa images have a good display of vertebral hemangiomas,which is helpful for the diagnosis of vertebral hemangiomas,especially for the lesions with larger volume and more fat content,and provides a new basis for clinical diagnosis of vertebral hemangiomas.3 The application of dual-source CT in the differentiation of vertebral osteolytic metastases and vertebral hemangiomas has further expanded the application range of dual-source CT and provided a new research direction.4 Compared with conventional CT,DSCT multi-parameter imaging can provide a variety of quantitative parameters and more diagnostic information,which can help improve the level of imaging diagnosis and guide clinical decision-making.