Yang Bin, Li Zheng-Liang, Gao Yi, Yang Ya-Ying, Zhao Wei
Medical Imaging Department, the First Affiliated Hospital, Dali University, Dali Department of Cardiology, Shanghai General Hospital Medical Imaging Department, the First Affiliated Hospital, Kunming Medical University, Kunming, China.
Medicine (Baltimore). 2017 Mar;96(11):e6175. doi: 10.1097/MD.0000000000006175.
To investigate the radiation dose and image quality for iterative reconstruction combined with the CARE kV technique in chest computed tomography (CT) scanning for physical examination.
A total of 130 patients who underwent chest CT scanning were randomly chosen and the quality reference value was set as 80 mAs. The scanning scheme was set and the patients were randomly divided into groups according to the scanning scheme. Sixty patients underwent a chest scan with 100 kV using the CARE kV technique and SAFIRE reconstruction (value=3) (experimental group) and the other 70 patients underwent chest scanning with 120 kV (control group). The mean CT value, image noise (SD), and signal-to-noise ratio (SNR) of the apex of the lung, the level of the descending aorta bifurcation of the trachea, and the middle area of the left atrium were measured. The image quality was assessed on a 5-point scale by two radiologists and results of the two groups were compared. The CT dose index of the volume (CTDIvol), dose length product (DLP), and effective dose (ED) were compared.
All the images for both groups satisfied the diagnosis requirement. There was no statistical difference in the image quality between the two methods (P > 0.05). The mean CT value of the apex of the lung, the level of the descending aorta bifurcation of the trachea, and the middle area of the left atrium were not significantly different for both groups (P > 0.05), while the image noise (SD) and the signal-to-noise ratio (SNR) of the apex of the lung, the level of the descending aorta bifurcation of the trachea, and the middle area of the left atrium were statistically different for both groups (P < 0.05). The CTDIvol was 3.29 ± 1.17 mGy for the experimental group and 5.30 ± 1.53 mGy for the control group. The DLP was 114.9 ± 43.73 mGy cm for the low-dose group and 167.6 ± 44.59 mGy cm for the control group. The ED was 1.61 ± 0.61 mSv for the low-dose group and 2.35 ± 0.62 mSv for the control group (P < 0.05).
The CARE kV technique combined with iterative reconstruction for chest CT scanning for physical examination could reduce the radiation dosage and improve CT image quality, which has a potential clinical value for imaging the thorax.
探讨迭代重建联合CARE kV技术在胸部计算机断层扫描（CT）体检中的辐射剂量及图像质量。
随机选取130例行胸部CT扫描的患者，将质量参考值设定为80 mAs。设定扫描方案，并根据扫描方案将患者随机分组。60例患者采用CARE kV技术及SAFIRE重建（值=3），以100 kV进行胸部扫描（实验组），另外70例患者以120 kV进行胸部扫描（对照组）。测量肺尖、气管降主动脉分叉水平及左心房中部区域的平均CT值、图像噪声（标准差）及信噪比（SNR）。由两名放射科医生采用5分制对图像质量进行评估，并比较两组结果。比较容积CT剂量指数（CTDIvol）、剂量长度乘积（DLP）及有效剂量（ED）。
两组所有图像均满足诊断要求。两种方法的图像质量无统计学差异（P>0.05）。两组肺尖、气管降主动脉分叉水平及左心房中部区域的平均CT值无显著差异（P>0.05），而两组肺尖、气管降主动脉分叉水平及左心房中部区域的图像噪声（标准差）及信噪比（SNR）有统计学差异（P<0.05）。实验组的CTDIvol为3.29±1.17 mGy，对照组为5.30±1.53 mGy。低剂量组的DLP为114.9±43.73 mGy cm，对照组为167.6±44.59 mGy cm。低剂量组的ED为1.61±0.61 mSv，对照组为2.35±0.62 mSv（P<0.05）。
CARE kV技术联合迭代重建用于胸部CT体检扫描可降低辐射剂量并提高CT图像质量，对胸部成像具有潜在临床价值。
