基于BMI调节管电压的前瞻性大螺距CT冠状动脉成像研究

Body mass index-adapted tube voltage prospectively ECG-triggered high-pitch coronary CT angiography

目的： CT冠状动脉成像目前已经广泛应用于临床，然而它的高辐射剂量一直受到人们的关注，降低CT冠状动脉检查的辐射剂量有重要的社会意义。文中探讨基于患者BMI调节管电压的前瞻性大螺距CT冠状动脉成像（ CT coronary angiography， CTCA）的可行性。方法选取102例患者并行CTCA检查，其中实验组（72例）采用基于BMI调整管电压，BMI＜23 kg／m2者选择70 kV，BMI 23～25 kg／m2之间者选择80 kV，BMI＞25 kg／m2者行自动管电压选择技术；对照组（30例）采用120 kV前瞻性序列心电门控技术行CTCA。评估并比较2组的主观和客观图像质量及辐射剂量。结果实验组右冠状动脉CT值高于对照组[（562．2±152．3）HU vs （399．6±61．3）HU]；实验组左冠状动脉主干CT值高于对照组[（571．1±159．5）HU vs （380．3±46．2）HU]；实验组前降支CT值高于对照组[（559．4±140．9）HU vs （356．0±39．7）HU]；实验组回旋支的CT值高于对照组[（553．0±168．6）HU vs （348．9±52．3）HU]，差异均有统计学意义（P＜0．001）。而实验组右冠状动脉、左冠状动脉主干、前降支和回旋支的对比噪音比与对照组比较，差异均无统计学意义（P＞0．05）。2组主观图像质量的差异亦无统计学意义（P＝0．604）。实验组的有效剂量明显低于对照组[（0．5±0．5）mSv vs （4．5±1．3）mSv， P＜0．001]。实验组相比于对照组120 kV前瞻性序列扫描CTCA辐射有效剂量降低了88．9％。结论基于患者BMI调节管电压的前瞻性大螺距CTCA具有可行性。

[Abstract ] Objective CT coronary angiography （CTCA） is now generally used in clinical practice, but its high radiation has been drawing constant attention .This study was to assess the feasibility of body mass index （BMI）-adapted tube voltage prospec-tively ECG-triggered high-pitch CTCA . Methods A total of 102 patients with or suspected with coronary heart disease undergoing CTCA were assigned to an experimental group （n=72） and a control group （n=30）, the former with BMI-adapted tube voltage （70 kV for BMI〈23 kg/m2 , 80 kV for BMI 23-25 kg/m2 , and automated tube voltage for BMI 〉25 kg/m2 ） while the latter with 120 kV prospectively ECG-triggered sequential technique .Objective and subjective image quality and radiation dose were evaluated and com -pared between the two groups . Results Compared with the control group , the experimental group showed significant increases in the CT values of the right coronary artery （[399.6 ±61.3] vs [562.2 ±152.3] HU）, left main coronary artery （[380.3 ±46.2] vs [571.1 ±159.5] HU）, left anterior descending artery （[356.0 ±39.7] vs [559.4 ±140.0] HU）, and left circumflex artery