光谱CT虚拟单能量冠状动静脉一体化成像的可行性分析

Feasibility analysis of spectral CT virtual monoenergetic imaging for one-stop coronary artery and vein examination

目的应用双层探测器光谱CT虚拟单能量成像技术尝试完成心脏冠状动脉和冠状静脉一体化成像。方法收集了2023年12月—2024年1月采用了个性化扫描方案进行冠状动静脉CT成像的受检者25例作为实验组,随机抽取我院同一时间段采用常规扫描方案进行冠状动脉CT成像的受检者25例作为对照组。将对照组常规图像作为A组,将实验组常规图像作为B1组,B1组通过虚拟单能级重建生成40 keV图像作为B2组。对A组、B1组、B2组的图像质量进行客观评价和主观评价;客观评价内容包括冠状动脉各分支的CT值、信噪比(SNR)和对比噪声比(CNR)。主观评价由两名高年资影像医师按照5分法完成,主观评分两位评分者的一致性分析采用Kappa检验;组间比较采用Mann-Whitney检验。结果实验组B2组的冠状动脉各分支的CT值、SNR和CNR[左冠状动脉主干CT值:(1306.07±185.16)HU、SNR:101.820±38.10、CNR:113.91±42.13;右冠状动脉CT值:(1284.97±203.8)HU、SNR:99.99±37.61、CNR:112.10±41.53;左回旋支CT值:(1191.88±182.83)HU、SNR:93.01±36.10、CNR:105.11±39.92;左前降支CT值:(1202.44±185.50)HU、SNR:88.05±33.57、CNR:106.33±41.84]均较实验组B1组和对照组A组的高,其结果差异具有统计学意义(P均<0.001)。实验组B2组的冠状静脉各分支(冠状静脉窦、心大静脉、后室间静脉、前室间静脉、左心室后静脉、左边缘静脉)的CT值、SNR和CNR值明显高于实验组B1组,结果差异具有统计学意义(P均<0.001)。两位医师对B2组图像质量的主观评分均为5(5,5),优于对照组A组和实验组B1组,且主观评价一致性较好(Kappa>0.7),说明B2组对于冠状动静脉的显示效果和图像质量更好。结论结合光谱CT虚拟单能量成像技术,能实现冠状动脉和冠状静脉的一体化成像。

Objective To study the feasibility of spectral CT virtual monoenergetic imaging(VMI)for one-stop coronary artery and vein examination.Methods From December 2023 to January 2024,an experimental group of 25 patients underwent coronary artery and vein CT imaging using personalized scanning protocols and a randomly selected controlled group of 25 patients underwent coronary artery CT imaging using routine scanning protocols.The conventional images of the experimental group as group B1,and the 40 keV virtual monoenergetic reconstructed images as group B2.The CT image quality of the control group(A),conventional CT(B1)and 40 keV VMI(B2)of the experimental group was evaluated quantitively including CT values,signal-to-noise ratio(SNR),and contrast-to-noise ratio(CNR)of coronary artery branches.Subjective evaluations were completed by two experienced radiologists using a 5-point scale,and the inter-rater reliability was analyzed using the Kappa test.Group comparisons were conducted using the Mann-Whitney test.Results CT values,SNR and CNR of the left main coronary arteries[(1306.07±185.16)HU,101.820±38.10,113.91±42.13],right coronary arteries[(1284.97±203.8)HU,99.99±37.61,112.10±41.53],left circumflex coronary arteries[(1191.88±182.83)HU,93.01±36.10,105.11±39.92],and left anterior descending arteries[(1202.44±185.50)HU,88.05±33.57,106.33±41.84]in group B2 were significantly higher(P<0.001)than that of groups A and B1.The CT values,SNR and CNR values of the coronary veins including coronary sinus,great cardiac vein,posterior intraventricular vein,anterior interventricular vein,posterior vein of the left ventricle,and left marginal vein in group B2 were also significantly higher(P<0.001)than that of group B1.The subjective image quality scores of B2 group(5,5)were better than that of groups A and B1 with good consistency(κ>0.7).Conclusion Spectral CT VMI allows one-stop examination of the coronary arteries and veins.