Yin Wei-Hua, Lu Bin, Gao Jian-Bo, Li Pei-Ling, Sun Kai, Wu Zhi-Feng, Yang Wen-Jie, Zhang Xiao-Qin, Zheng Min-Wen, McQuiston Andrew D, Meinel Felix G, Schoepf Uwe Joseph
Department of Radiology, State Key Laboratory of Cardiovascular Disease, Fu Wai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, #167 Bei-Li-Shi Street, Xi-Cheng District, Beijing 100037, People's Republic of China.
Department of Radiology, State Key Laboratory of Cardiovascular Disease, Fu Wai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, #167 Bei-Li-Shi Street, Xi-Cheng District, Beijing 100037, People's Republic of China.
J Cardiovasc Comput Tomogr. 2015 May-Jun;9(3):215-24. doi: 10.1016/j.jcct.2015.01.010. Epub 2015 Jan 22.
Both low tube voltage and sinogram-affirmed iterative reconstruction (IR) techniques hold promise to decrease radiation dose at coronary CT angiography (CCTA). The increased iodine contrast at low tube voltage allows for minimizing iodine load.
To assess the effect of reduced x-ray tube voltage, low iodine concentration contrast medium and IR on image quality and radiation dose at CCTA.
Two hundred thirty-one consecutive patients with suspected coronary artery disease were enrolled in this prospective, multicenter trial and randomized to 1 of 2 dual-source CCTA protocols: 120-kVp with 370 mgI/mL iopromide or iopamidol (n = 116; 44 women; 55.3 ± 9.8 years) or 100 kVp with 270 mgI/mL iodixanol (n = 115; 48 women; 54.2 ± 10.4 years). Reconstruction was performed with filtered back projection and IR. Attenuation, image noise, signal-to-noise ratio, and contrast-to-noise ratio were measured and image quality scored. Size-specific dose estimates and effective doses were calculated.
There were no significant differences in mean arterial attenuation (406.6 ± 76.7 vs 409.7 ± 65.2 Hounsfield units; P = .739), image noise (18.7 ± 3.8 vs 17.9 ± 3.4 Hounsfield units; P = .138), signal-to-noise ratio (22.5 ± 5.4 vs 23.7 ± 6.1; P = .126), contrast-to-noise ratio (17.5 ± 5.5 vs 18.3 ± 6.1; P = .286), or image quality scores (4.1 ± 0.9 vs 4.0 ± 0.9; P > .05) between 120-kVp filtered back projection-reconstructed and 100-kVp IR-reconstructed series. Mean iodine dose was 26.5% lower (18.3 ± 0.5 vs 24.9 ± 0.9 g; P < .0001), mean size-specific dose estimate was 35.1% lower (17.9 ± 6.6 vs 27.5 ± 8.2 mGy; P < .0001), and effective dose was 34.9% lower (2.3 ± 1.0 vs 3.5 ± 1.1 mSv; P < .0001) with the 100 kVp compared with the 120-kVp protocol, respectively.
Using low x-ray tube voltage and IR allows for decreasing the iodine load and effective radiation dose at CCTA while maintaining image quality.
低管电压和正弦图确认迭代重建（IR）技术都有望降低冠状动脉CT血管造影（CCTA）的辐射剂量。低管电压下碘对比剂用量的增加有助于减少碘负荷。
评估降低X射线管电压、低碘浓度对比剂和IR对CCTA图像质量和辐射剂量的影响。
231例连续的疑似冠心病患者纳入了这项前瞻性多中心试验，并随机分为两种双源CCTA方案中的一种：120 kVp联合370 mgI/mL的碘普罗胺或碘帕醇（n = 116；44名女性；55.3±9.8岁），或100 kVp联合270 mgI/mL的碘克沙醇（n = 115；48名女性；54.2±10.4岁）。采用滤波反投影和IR进行重建。测量衰减、图像噪声、信噪比和对比噪声比，并对图像质量进行评分。计算特定尺寸剂量估计值和有效剂量。
120 kVp滤波反投影重建系列和100 kVp IR重建系列之间，平均动脉衰减（406.6±76.7 vs 409.7±65.2亨氏单位；P = 0.739）、图像噪声（18.7±3.8 vs 17.9±3.4亨氏单位；P = 0.138）、信噪比（22.5±5.4 vs 23.7±6.1；P = 0.126）、对比噪声比（17.5±5.5 vs 18.3±6.1；P = 0.286）或图像质量评分（4.1±0.9 vs 4.0±0.9；P＞0.05）均无显著差异。与120 kVp方案相比，100 kVp方案的平均碘剂量降低了26.5%（18.3±0.5 vs 24.9±0.9 g；P＜0.0001），平均特定尺寸剂量估计值降低了35.1%（17.9±6.6 vs 27.5±8.2 mGy；P＜0.0001），有效剂量降低了34.9%（2.3±1.0 vs 3.5±1.1 mSv；P＜0.0001）。
使用低X射线管电压和IR可在保持图像质量的同时，降低CCTA的碘负荷和有效辐射剂量。
