双层探测器光谱CT单能量成像联合个性化注射方案在颅脑CT血管成像中的应用研究

目的:探讨双层探测器光谱CT单能量成像联合个性化对比剂注射方案在颅脑CT血管成像（CTA）中的应用价值。方法:回顾性分析2020年8月至11月在华中科技大学同济医学院附属协和医院采用双层探测器光谱CT和个性化对比剂注射方案行颅脑CTA检查的76例患者的影像资料。对基于双层探测器光谱CT数据重建生成的120 kVp混合迭...

The application value of monoenergetic imaging on dual-layer spectral detector CT combined with individual injection protocol in brain CT angiography

Objective To explore the value of monoenergetic imaging on dual-layer spectral detector CT combined with individual injection protocol of contrast medium in brain CT angiography(CTA).Methods Seventy-six patients who underwent brain CTA on the Philips IQon dual-layer spectral detector CT and individual injection protocol of contrast medium in Union Hospital of Tongji Medical College,Huazhong University of Science and Technology from August to November 2020 were retrospectively analyzed.Objective and subjective evaluation of image quality was performed in conventional energetic images(conventional group)which derived from 120 kVp hybrid iterative reconstruction algorithm and 50 keV virtual monoenergetic images(test group)which derived from spectral reconstruction algorithm.The objective evaluation content included CT values,signal-to-noise ratio(SNR)and contrast-to-noise ratio(CNR)of internal carotid artery and middle cerebral artery,CT values and standard deviation(SD)of brain parenchyma.The subjective evaluation was completed by two senior radiologists according to the 5-point scale,and the inter-agreement between two radiologists was evaluated by Kappa test.Paired t test or Wilcoxon rank test was used for analysis between two groups.Results The SNR and CNR of both internal carotid artery and middle cerebral artery,as well as CT values of internal carotid artery,middle cerebral artery and brain parenchyma,were significantly higher in test group than that in conventional group(all P<0.001).The subjective scores of two radiologists for test group were both 5(5,5)points,and the subjective scores for conventional group were both 4(4,4)points.The subjective scores of the radiologists were in good agreement,and the Kappa values were 0.74 and 0.84 respectively.The subjective scores of test group were significantly higher than that of conventional group(Z=-11.15,P<0.001).Conclusion Monoenergetic imaging on dual-layer spectral detector CT combined with individual injection protocol of contrast medium can improve SNR,CNR and the image quality of brain CTA.