The third-generation dual-source CT+flash mode scan combined with chest circumference index to reduce the radiation dose and iodine intake of coronary CTA
WANG Hailin, CHEN Minjiang, WENG Qiaoyou, LU Chenying, CHENG Shufang, YE Miaoqing, LIN Guihan, JI Jiansong
Department of Radiology, Lishui Central Hospital, Lishui 323000, China
WANG Hailin,CHEN Minjiang,WENG Qiaoyou, et al. The third-generation dual-source CT+flash mode scan combined with chest circumference index to reduce the radiation dose and iodine intake of coronary CTA[J]. JOURNAL OF WEZHOU MEDICAL UNIVERSITY, 2020, 50(1): 36-40.
Abstract：Objective: To explore the clinical application value of third-generation dual-source CT+flash mode scan combined with chest circumference index to reduce the radiation dose and iodine intake of coronary artery CT angiography (CTA). Methods: A total of 160 patients with clinically suspected coronary heart disease requiring coronary CTA examination were continuously selected and examined by trube-flash large pitch scan combined with iterative reconstruction technology. Tube current automatic adjustment technology care Dose 4D was operated. The control group included 60 cases, with tube voltage=120 kV, and the remaining 100 cases were in the low-dose group, which were sub-divided into groups A, B, and C according to the parameters of the chest circumference. Among them, the chest circumference of group A was≤85 cm, the tube voltage was 70 kV; group B was 85-90 cm, tube voltage=80 kV; group C was≥95 cm, tube voltage=90 kV. One-way analysis of variance was used to compare gender, age, BMI, chest circumference, tube voltage, tube current, right coronary CT value, SD value, SNR, CTD, DLP, radiation dose in four groups of patients; the comparison of subjective image quality score was performed by a nonparametric rank sum test. Results: The coronary image quality scores of the conventional group and the low-dose group (group A, group B, and group C) were 3.26±0.23, 3.18±0.19, 3.23±0.31, and 3.21±0.25, respectively. There was no significant difference between the groups (P>0.05), and the image quality met the requirements of clinical diagnosis. There were no significant differences in age, gender and heart rate between the 4 groups (P>0.05). The CT values of the four groups of right coronary artery were (425.94±69.59)Hu, (505.23±41.41) Hu, (463.83±59.68) Hu and (444.70±70.36) Hu, respectively, and there was statistical difference among the low-dose groups and the conventional group (P<0.01). The radiation doses were (1.03±0.15) mSv, (0.36±0.09) mSv, (0.57±0.05) mSv and (0.80±0.10) mSv (P>0.05); the iodine intakes were 18.50 g, 9.45 g, 12.80 g, and 14.40 g, respectively. The radiation dose and iodine intake of the low-dose groups were lower than the conventional group (P<0.01). Conclusion: The third-generation dual-source CT+flash mode scanning combined with chest circumference index can be applied to adjust the tube voltage and meanwhile the contrast agent with low iodine concentration can be taken to adjust the rate and total amount of contrast agent, thus effectively reducing the radiation dose and iodine intake while the image quality is ensured.
