The Preliminary Application Of Gemstone Spectral CT In The Diagnosis Of Lung Space Occupying Lesions

Objective:A preliminary study of gemstone spectral CT in the diagnosis and differential diagnosis of lung space occupying lesions.Materials and method:A retrospective selection of 51 cases with pulmonary occupying lesions confirmed by pathology were collected, including 19 cases of benign group and 32 cases of malignant group, selection of 28 lymph nodes operated to obtain pathological, including 16 metastatic lymph nodes, 12 benign non metastatic lymph node, all used gemstone spectral CT energy spectrum mode scanning, reconstruction into 70 Ke V single energy image, storing roisave data in.Csv format from the workstation, extracted(1) the CT value(HU) of 40-140 ke V(10ke V intervals) energy levels, slope calculation each CT spectrum curve of the lesion ROI;(2) the iodine radical focus value(100ug/ml) and water-based value(mg/ml), the value of iodine radical(100ug/ml) and water-based value(mg/ml) with the same level of the descending aorta/left subclavian artery, standard iodine based values and standardization of water-based value and standardization value difference calculation of each lesion;(3) the effective-z of the lesions ROI. The data obtained compared by the method of independent sample t test, P<0.05 said with statistically significant difference.Result:1.Comparison each parameter of benign and malignant lung space occupying group s: in the arterial phase the CT value of 40 ke V, 50 ke V level and the energy spectrum curve slope compared with statistically significant difference(P<0.05); in the venous phase CT value of 40 ke V-120 ke V level and the energy spectrum curve slope compared with statistically significant difference(P<0.05); the CT value of arterial and venous phase difference of 40 ke V-80 ke V level compared with statistically significant differe nce(P<0.05). In the arterial phase and venous phase iodine based images the standardization of iodine concentrations of the benign group were lower than malignant group, this difference has statistical difference(P<0.05); In the venous phase the benign and malignant lesions group iodine value were increased than the arterial phase; there was also significant difference of iodine standard difference(P<0.05); water value, water based value difference and the effective atomic number difference was not statistical significance.2.Comparison each parameter of benign and malignant thoracic lymph node groups: in the arterial phase the CT value of 40 ke V-80 ke V levels and the energy spectrum curve slope compared with statistically significant difference(P<0.05); in the venous phase the CT value of 40 ke V-70 ke V level and the energy spectrum curve slope compared with statistically significant difference(P<0.05). The standard iodine concentration of the benign lymph node group in the arterial phase and venous phase iodine based images was higher than that of the malignant group, this difference has statistical difference(P<0.05); In the venous phase the standard iodine concentration of benign and malignant group increased than that in the arterial phase; the difference of standard iodine value difference between both benign and malignant group has statistical significance(P<0.05); water base value, water-based value difference and the effective atomic number difference was not statistical significance.3.The homology analysis of thoracic lymph node and lung space occupying lesion: The spectrum curve slope of the malignant lung lesions and the metastasis lymph node from malignant lesions in arterial phase is similar, this difference has no significant difference(P>0.05), the standard iodine based value, the slope of the curve in venous phase difference of the group was statistically significant(P<0.05); The standard iodine concentration, the curve slope of the benign lung lesions and the non-metastasis lymph nodes from benign lesions compared with statistically significant(P<0.05).The differences of the curve slope in the both two phase of the malignant lung lesions and non- metastatic lymph nodes from malignant lesions are obvious, with significant difference(P<0.05), the standard iodine based value difference of the group have not statistical significance(P>0.05).Conclusion:1.The CT value and the spectrum curve slope under 40 ke V, 50 ke V level in the arterial phase, 40 ke V-120 ke V level in the venous phase, the CT value difference between the arterial phase and venous phase under 40 ke V-80 ke V level, and the standardization of iodine concentration, standardization of iodine concentration difference in the differential diagnosis of Malignant and benign pulmonary lesions has the significance.2.The CT value and the energy spectrum curve slope under 40 ke V-80 ke V level in the arterial phase, 40 ke V-70 ke V level in the venous phase, and the standardization of iodine concentration, standardization of iodine concentration differ ence have certain reference significance for non metastatic lymph node and metastatic lymph node identification, this contributes to lung cancer N staging.3.The spectrum curve slope in the arterial phase of the lung cancer and the homologous metastatic lymph nodes is similar, The curve slope in the both two phase of the lung cancer and the non homologous non- lymph node metastasis have obvious differences, the differences help qualitative of the lymph nodes.