The Application Studies Of Spectral CT Imaging In Breast Cancer Diagnosis

Part One: The Spectral CT Features of Normal BreastObjective To explore the spectral CT features of normal breast.Methods Fifteen cases with other chest disease that underwent chest plain and dual phase contrast enhanced scans with gemstone spectral CT were included in this study,all of these cases are female and without any breast disease.15 cases were analyzed with the spectral CT post-processing and analysis software,monochromatic level(ke V)that shows normal breast with optimal CNR,the CT values(HU)at40ke V~140ke V,spectral curves and curve slopes at 40 ke V~70ke V were obtained in CT plain,arterial and venous phase respectively;average iodine contents(mg/cc)and relative iodine contents of normal breast in arterial and venous phase.We used x±s and 95% confidential interval(CI)for statistical description,one-way ANOVA was used to compare the curve slopes in CT plain,arterial and venous phase.Results The average monochromatic level that show normal breast with optimal CNR in CT plain,arterial and venous phase scans were 65.55±0.82 ke V,65.70±0.80 ke V,65.80±0.69 ke V,95% CI were(65.2,65.95)ke V,(65.35,66.05)ke V,(65.50,66.10)ke V,respectively.The CT values at 40 ke V~140ke V in arterial and venous phase were higher than those in CT plain scanning,especially in venous phase.The spectral curve slopes at 40 ke V~70ke V of normal breast in CT plain,arterial and venous phase were 0.46±0.07,0.45±0.05,0.52±0.08,there was no statistically significant between three curve slops.Average iodine contents of normal breast in dual-phase enhanced were 1.42±0.30mg/cc,2.10±0.40mg/cc,95% CI were(1.13,1.72)mg/cc,(1.63,2.62)mg/cc.The relative iodine contents were 0.02±0.003,0.06±0.005;95% CI were(0.01,0.03),(0.05,0.08)in arterial and venous phase respectively.Conclusions The normal breast had the characteristic spectral CT parameters and could provide theoretical basis for subsequent research.Part Two: The Spectral CT Features of Breast CancerObjective To explore the spectral CT features of breast cancer and evaluate the clinical application of the spectral CT in breast cancer diagnosis.Methods Spectral CT images of 12 cases with breast cancer verified by operation and pathology were analyzed retrospectively,including ten invasive ductal carcinoma and one invasive lobular carcinoma and one invasive papillary carcinoma.All cases underwent chest dual phase contrast enhanced scans with gemstone spectral CT,all of these cases were analyzed with the spectral CT post-processing.The CT values(HU)at40ke V~140ke V,curve slopes at 40 ke V~70ke V,average iodine contents(mg/cc)and relative iodine contents of breast cancer and the contralateral normal breast in arterial and venous phase were measured.12 female cases underwent dual phase contrast enhanced scans with traditional CT were included randomly as the control group,the radiation dose parameters CT dose index volume(CTDIvol),dose length product(DLP)and effective dose(ED)were recorded.The Spectral CT parameters comparison between breast cancer and normal breast and the radiation dose comparison between spectral CT and traditional CT were done with independent sample t-test.Results Breast cancer had higher CT values at 40 ke V~140ke V,average iodine contents,relative iodine contents and curve slopes compared to the normal breast,and the difference between two groups was statistically significant(P<0.05);The radiation dose of spectral CT was lower compared to the traditional CT,and the difference between two groups was statistically significant(P<0.05).Conclusions Breast cancer had characteristic spectral parameters and lower radiation dose so spectral CT having the clinical application in diagnosing of breast cancer.Part Three: The Spectral CT Features of Breast CancerMetastatic Lymph NodesObjective To explore the application value of spectral CT in diagnosing the metastatic lymph nodes of breast cancer.Methods 12 cases with breast cancer verified by operation and pathology were analyzed retrospectively,metastatic lymph nodes was found in 6 patients,including 5axillary lymph nodes and 1 interpectoral lymph node involved.6 metastatic lymph nodes and breast cancer primary lesions spectral features were analyzed and the spectral curve,histogram,scatter plot were drawn in arterial and venous phase respectively,aim to research the application of spectral CT in diagnosing the metastatic lymph nodes.Results 6 metastatic lymph nodes spectral features were analyzed,the results showed that metastatic lymph nodes having the similar or same morphological characteristics of spectral curve,histogram,scatter plot with breast cancer primary lesions,and more consistent in venous phase compared with arterial phase.Conclusions The consistence of spectral curve,histogram and scatter plot of metastatic lymph nodes and primary lesions having the application value in diagnosing the metastatic lymph nodes of breast cancer,and providing more supplementary information for preoperative staging of breast cancer.