摘要
目的探讨双源CT的CARE-k V扫描技术在冠状动脉成像（CTCA）的辐射剂量是否符合个体化低剂量要求。方法将接受CTCA检查的200例患者按随机数字法分成两组：A组100例,应用CARE-k V技术智能选择管电压;B组100例,根据患者的体质量指数（BMI）确定管电压,两组均应用CREA Dose 4D技术自动选择管电流。测量并记录两组患者主动脉根部及左冠状动脉主干的CT值,并进一步计算信噪比（CNR）和对比噪声比（SNR）值,以用于客观图像质量评估。然后由两名医师通过4分评价法对两组图像质量进行主观评价,取其均值纳入统计学分析。比较两组CNR、SNR、容积CT剂量指数（CTDIvol）、有效剂量（ED）。结果 A组客观图像质量（左主干CT值和SNR）优于B组（P〈0.05）,主观图像质量差异无统计学意义（P=0.56）;A组较B组CTDIvol降低23.71%[（30.41±18.93）m Gy vs.（39.86±20.13）m Gy,P=0.001],ED降低22.94%[（5.81±2.87）m Sv vs.（7.54±3.94）m Sv,P=0.001]。且A组较B组明显增加了80 k V管电压的应用率（χ~2=14.559,P=0.001）。结论应用CARE-k V智能最佳k V扫描技术进行CTCA,能降低受检者接受的辐射剂量且同时提高图像质量,较BMI能更好地符合个体化辐射剂量需要。
Objective To investigate the effect of CARE-k V on individual radiation dosage and image quality by using dual source CT coronary angiography（ CTCA）. Methods Two hundred patients who were performed CTCA were prospectively studied and divided into two groups according to random number table： Group A（ 100 patients） underwent dual-source CTCA with CARE-k V,tube voltage was selected automatically; group B（ 100patients） underwent CTCA with a body mass index（ BMI）-based tube potential,tube current was selected by CARE Dose 4D in both groups. Quantitative image quality parameter,including image noise,attenuation,signal-noise ratio（ SNR） and carrierto noise ratio（ CNR）,the CT attenuation in a region of interest placed in the aortic root and left main（ LM） were measured. The scores of imaging quality were evaluated by two experienced reviewers,and SNR,CNR,CTDIvol,effect dose（ ED） were compared between the two groups. Results The value of the attenuation and SNR of LM in group A were significantly higher than that in group B（ P〈0. 05）. No significant differences were found on image noise and CNR between group A and group B（ P = 0. 56）. The value of CTDIvol in group A was23. 71% lower than that in group B [（ 30. 41 ± 18. 93） m Gy vs.（ 39. 86 ± 20. 13） m Gy,P = 0. 001 ],and ED was22. 94% lower than that in group [（ 5. 81 ± 2. 87） m Sv vs.（ 7. 54 ± 3. 94） m Sv,P = 0. 001]. The use of tube voltage of 80 k V in group A were significantly more frequent（ χ2= 14. 559,P = 0. 001）. Conclusion The application of CARE-k V in dual source coronary CT angiography can significantly reduce radiation dose and improve image quality,and therefore can meet the need of individual.
出处
《心血管外科杂志（电子版）》
2015年第3期13-17,共5页
Journal of Cardiovascular Surgery(Electronic Edition)
基金
贵州省社会发展攻关项目(黔科合SY字[2011]3057号)
