宝石能谱CT成像对乳腺浸润性导管癌的诊疗价值

目的:探讨宝石能谱CT成像（gemstone spectral imaging，GSI）在乳腺浸润性导管癌诊疗中的价值。方法:手术及病理证实的乳腺浸润性导管癌患者32例，共有病灶47个。由两位从事乳腺影像工作的副主任医师对图像进行盲评，分析乳腺浸润性导管癌病灶的影像特点及能谱特征。以软件自动生成的KeV-CT值曲线作为观察指标，分析浸润性导管癌病灶同正常腺体的差异。按病理结果将淋巴结分为转移组和非转移组；以淋巴结的KeV-CT值曲线斜率、碘基值以及淋巴结CT值与主动脉CT值的比值为评价指标，比较转移组淋巴结和非转移组淋巴结上述数值的差异。结果:GSI共检出44个病灶，病灶的最佳单能量图像KeV值在66~68KeV之间。碘/水(Iodine/Water)基物质图、水/脂（Water/Fat）基物质图对病灶范围、毛刺（40/44）、分叶（36/44）、钙化（11/44）、胸壁侵犯（7/44）有更清晰的显示。增强后病灶轻中度强化，CT值增加(20±6)HU。最佳单能量40KeV CTA能清晰显示肿瘤血管，以胸廓内动脉及胸外侧动脉为主（29/44）。浸润性导管癌病灶KeV-CT值曲线，与正常腺体差异明显。腋窝转移淋巴结同非转移淋巴结KeV-CT值曲线斜率在40~70KeV间差异明显，P<0.01（t=-5.5），差异有统计学意义。不同KeV下转移组同非转移组HU淋巴结/HU主动脉差异无统计学意义。转移组与非转移组淋巴结碘基值平均值，差异有统计学意义，P<0.05（t=-2.1）。结论:GSI能提高小病灶及多发病灶的检出率。可以较准确地评估乳腺浸润性导管癌位置、范围、胸壁侵犯、腋窝淋巴结转移及血供情况，对乳腺浸润性导管癌的诊疗有较大的指导价值。

Preliminary study of spectral imaging on diagnosis of infiltrating ductal breast carcinoma

Objective:To evaluate the clinical feasibility of Gemstone Spectral imaging in the diagnosis and treat-ment of infiltrating ductal breast carcinoma.Mehtods:All 32 cases pathologically proved with infiltrating ductal breast carcinoma underwent spectral CT scan.Images and the spectrum feature of the lesions were evaluated by two deputy chief physicians.The KeV-CT curve made by the software was used to compare the difference of infiltrating ductal breast carcinoma lesions and the normal breast tissue.The lymph nodes were classified as metastasis and non-metas-tasis by pathology.The slope of the KeV-CT curve,Iodine-water density,CT attenuation values ratio of lymph nodes and aorta (defined by the formula:CT lymph nodes/CT aorta)in ROIs were recorded.Results:The GSI had found 44 lesions.The optimal single energy of 66~68keV showed the best contrast of lesion.Material decomposition images of water(fat)and idone(water)showed the lesion extent,sub-lobe sign (40/44)spiculation (36/44),calcification (1 1/44),chest invasion (7/44)clearly.The lesions were mild to moderate enhanced by (20 ±6)HU.The KeV-CT curves of the tumors significantly different from the normal breast tissue.Blood supply to tumor by the internal thoracic artery and the lateral thoracic artery(29/44)can be clearly showed in the optimal monochromatic images of 40KeV. The slope of KeV -CT curve of axillary metastatic lymph nodes were significantly different from non -metastatic lymph nodes(t =-5.5,P<0.01).The CT attenuation values ratio of lymph nodes and aorta had no significant differences between metastasis and non-metastasis.The Iodine-water density value of metastatic lymph nodes were significantly lower than the non-metastasis(t=-2.1,P<0.05).Conclusion:GSI is able to improve the detectable rate of small lesions and multiple lesions.Spectral imaging of breast cancer can be evaluated by different kinds of ima-ges(including monochromatic images,material decomposition)and have great value of accurately diagnosis of infiltra-ting ductal breast carcinoma by assessing the lesion extent,sub-lobe sign,spiculation,calcification,chest invasion, axillary lymph nodes invasion and blood supply evaluation.