Objective To investigate the value of multiple quantitative parameters derived from Hawk spectral CT in predicting lymph node metastasis in papillary thyroid carcinoma(PTC).Methods Preoperative Hawk spectral CT images of 57 cancerous foci from 44 PTC patients confirmed by surgery and pathology were retrospectively collected.All patients underwent lymph node dissection.Based on pathological results,the patients were categorized into metastatic group(26 patients with 35 cancerous foci)and non-metastatic group(18 patients with 22 cancerous foci).The CT morphological features of the primary PTC lesions included location,diameter,bite-cookie sign,and calcification,respectively.Quantitative parameters of Hawk spectral CT plain scan,arterial phase(AP)and venous phase(VP),including conventional CT values,virtual monoenergetic imaging(MonoE)CT values(40 keV,100 keV),effective atomic number(Zeff)and electron density(Rho),respectively.The rank sum test or chi-square test was used to compare the differences in CT morphological features and Hawk spectral CT quantitative parameters between the two groups.For parameters with significant differences,logistic regression was used to construct a combined model.Area under the curve(AUC),accuracy,sensitivity,and specificity were used to evaluate the effectiveness of the combined model.Results There was statistically significant difference in the diameter of the primary lesion between the metastatic group and the non-metastatic group(P＜0.05),and the diameter of the primary lesion in the metastatic group was larger than that in the non-metastatic group.The conventional CT value,MonoE CT values(40 keV,100 keV),Rho and Zeff in plain scan,AP-Rho,and VP-MonoE CT value(100 keV)of the primary lesion in the metastatic group were all significantly lower than those in the non-metastatic group(P＜0.05).The AUC,accuracy,sensitivity and specificity of the Hawk spectral CT plain scan parameter combination model were 0.765,0.754,0.800,and 0.682,respectively.The AUC,accuracy,sensitivity,and specificity of the Hawk spectral CT enhancement parameter combination model were 0.726,0.667,0.600,and 0.786,respectively.Conclusion Through the analysis of multiple quantitative parameters from Hawk spectral CT of PTC primary lesion,the primary lesion in the metastatic group exhibited significant differences from those in the non-metastatic group in multiple quantitative parameters,which can further improve the predictive efficacy for lymph node metastasis.

Objective To investigate the value of multiple quantitative parameters derived from Hawk spectral CT in predicting lymph node metastasis in papillary thyroid carcinoma(PTC).Methods Preoperative Hawk spectral CT images of 57 cancerous foci from 44 PTC patients confirmed by surgery and pathology were retrospectively collected.All patients underwent lymph node dissection.Based on pathological results,the patients were categorized into metastatic group(26 patients with 35 cancerous foci)and non-metastatic group(18 patients with 22 cancerous foci).The CT morphological features of the primary PTC lesions included location,diameter,bite-cookie sign,and calcification,respectively.Quantitative parameters of Hawk spectral CT plain scan,arterial phase(AP)and venous phase(VP),including conventional CT values,virtual monoenergetic imaging(MonoE)CT values(40 keV,100 keV),effective atomic number(Zeff)and electron density(Rho),respectively.The rank sum test or chi-square test was used to compare the differences in CT morphological features and Hawk spectral CT quantitative parameters between the two groups.For parameters with significant differences,logistic regression was used to construct a combined model.Area under the curve(AUC),accuracy,sensitivity,and specificity were used to evaluate the effectiveness of the combined model.Results There was statistically significant difference in the diameter of the primary lesion between the metastatic group and the non-metastatic group(P＜0.05),and the diameter of the primary lesion in the metastatic group was larger than that in the non-metastatic group.The conventional CT value,MonoE CT values(40 keV,100 keV),Rho and Zeff in plain scan,AP-Rho,and VP-MonoE CT value(100 keV)of the primary lesion in the metastatic group were all significantly lower than those in the non-metastatic group(P＜0.05).The AUC,accuracy,sensitivity and specificity of the Hawk spectral CT plain scan parameter combination model were 0.765,0.754,0.800,and 0.682,respectively.The AUC,accuracy,sensitivity,and specificity of the Hawk spectral CT enhancement parameter combination model were 0.726,0.667,0.600,and 0.786,respectively.Conclusion Through the analysis of multiple quantitative parameters from Hawk spectral CT of PTC primary lesion,the primary lesion in the metastatic group exhibited significant differences from those in the non-metastatic group in multiple quantitative parameters,which can further improve the predictive efficacy for lymph node metastasis.

Objective To evaluate the value of computed tomography myelography(CTM)in diagnosing the laceration of brachial plexus. Methods Sixteen cases with brachial plexus injury underwent thin-slice high resolution CT scanning two hours after the examination of conventional lumber puncture myelographs.The results of CTM in patients were compared with surgical exploretation and seven patients underwent preoperatively electrophysiological examination .Results There were totally 28 nerve roots injury.Of them,26 were detected by CTM,the accuracy was 92.8%.The main signs of nerve root laceration were the disapperance of the filling defect of ventral and forsal root,the indirect signs were false meningeal cyst,displacement and deformation of spinal cord,twist of nerve root.Conclusion CT myelography is of significant value in diagnosing the laceration of nerve root.