Mera Fernández D, Santos Armentia E, Bustos Fiore A, Villanueva Campos A M, Utrera Pérez E, Souto Bayarri M
Departamento de Radiología, Hospital Povisa, Vigo, Pontevedra, España.
Departamento de Radiología, Hospital Povisa, Vigo, Pontevedra, España.
Radiologia (Engl Ed). 2018 Jul-Aug;60(4):312-319. doi: 10.1016/j.rx.2018.02.009. Epub 2018 Apr 23.
To assess the ability of dual-energy CT (DECT) to reduce metal-related artifacts in patients with clips and coils in head CT angiography, and to analyze the differences in this reduction between both type of devices.
Thirteen patients (6 clips, 7 coils) were selected and retrospectively analized. Virtual monoenergetic images (MEI) with photon energies from 40 to 150 keV were obtained. Noise was measured at the area of maximum artifact. Subjective evaluation of streak artifact was performed by two radiologists independently. Differences between noise values in all groups were tested by using the ANOVA test. Mann-Whitney U test was used to compare the differences between clips and coils. Coheńs κ statistic was used to determine interobserver agreement.
The lowest noise value was observed at high energy levels (p<0,05). Noise was higher in the coil group than in the clip group (p<0.001). Interobserver agreement was good (κ=0.72).
TCED with MEI helps to minimize the artifact from clips ands coils in patients who undergo head CT angiography. The reduction of the artifact is greater in patients with surgical clipping than in patients with endovascular coiling.
评估双能CT（DECT）减少头部CT血管造影中存在夹子和线圈的患者金属相关伪影的能力，并分析这两种装置在伪影减少方面的差异。
选取13例患者（6例有夹子，7例有线圈）并进行回顾性分析。获得了光子能量从40到150 keV的虚拟单能图像（MEI）。在最大伪影区域测量噪声。由两名放射科医生独立对条纹伪影进行主观评估。使用方差分析检验所有组噪声值之间的差异。采用曼-惠特尼U检验比较夹子和线圈之间的差异。使用科恩κ统计量确定观察者间的一致性。
在高能级观察到最低噪声值（p<0.05）。线圈组的噪声高于夹子组（p<0.001）。观察者间一致性良好（κ=0.72）。
采用MEI的双能CT有助于使接受头部CT血管造影的患者中夹子和线圈产生的伪影最小化。手术夹闭患者的伪影减少比血管内栓塞患者更大。
