Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao, China.
Department of Ultrasound, The Affiliated Hospital of Qingdao University, Qingdao, China.
J Xray Sci Technol. 2018;26(3):463-471. doi: 10.3233/XST-17332.
640-slice coronary CT angiography is becoming an accurate and reliable method of diagnosing coronary heart disease. However, how to reduce the radiation dosage while ensuring the clinically acceptable image quality remains a quite challenging issue.
To evaluate the effect of low tube voltage on radiation dosage under 640-slice coronary CT angiography (CCTA).
Four hundred patients (236 males, 164 females) with coronary heart disease and underwent CCTA using DCVT were classified into A1 (tube voltage: 120 kV; exposure phase window: 30-80%), B1 (120 kV; 70-80%), A2 (100 kV; 30-80%) and B2 group (100 kV; 70-80%), respectively. Image qualities and effective dose (ED) were assessed and compared.
No significant differences were observed among the groups in terms of age, height, weight and body mass index (BMI) (P > 0.05). ED were significantly lower in 100 kV group (P < 0.05). CT values of coronary artery in 100 kV groups were 13.5% and 17.3% higher than 120 kV group. ED in B1 group were 64.5% and 67.0% lower than A1 group. ED in B2 group were 65.4% and 65.2% lower than A2 group.
When using a 640-slice CCTA prospective ECG-gating scanning mode, it is preferable to use a 100 kV tube voltage setting because compared to 120 kV tube voltage protocol, it seems to significantly decrease the mean effective radiation dose, without significantly lowering both the subjective and objective image quality.
640 层冠状动脉 CT 血管造影术已成为一种准确可靠的冠心病诊断方法。然而，如何在保证临床可接受的图像质量的同时降低辐射剂量仍是一个极具挑战性的问题。
评估低管电压对 640 层冠状动脉 CT 血管造影术（CCTA）辐射剂量的影响。
将 400 例冠心病患者（男 236 例，女 164 例）分为 A1 组（管电压：120 kV；曝光相位窗：30-80%）、B1 组（120 kV；70-80%）、A2 组（100 kV；30-80%）和 B2 组（100 kV；70-80%），采用管电压调制技术进行 CCTA。评估并比较图像质量和有效剂量（ED）。
各组患者年龄、身高、体重和体重指数（BMI）比较差异均无统计学意义（P＞0.05）。100 kV 组的 ED 显著降低（P＜0.05）。100 kV 组冠状动脉 CT 值分别比 120 kV 组高 13.5%和 17.3%。B1 组 ED 比 A1 组分别低 64.5%和 67.0%。B2 组 ED 比 A2 组分别低 65.4%和 65.2%。
在使用 640 层 CCTA 前瞻性心电门控扫描模式时，采用 100 kV 管电压设置更为可取，因为与 120 kV 管电压方案相比，它似乎能显著降低平均有效辐射剂量，同时不显著降低主观和客观图像质量。
