论文部分内容阅读
目的探讨体重指数(BMI)适应性电流、电压结合前置门控技术对降低冠状动脉CT血管成像(CCTA)辐射剂量及提高图像噪声均匀度的可行性。资料与方法将120例拟行CCTA检查的患者随机分成A、B两组。A组采用固定电流、电压的回顾性心电门控模式;B组采用BMI适应性电流、电压的前置心电门控模式,记录患者的身高、体重、BMI、电流、电压、噪声值、CT剂量指数(CTDI)、有效剂量(ED)等。图像质量评分采用4点评分法。采用SPSS13.0软件对数据进行统计学处理。结果对A组图像噪声与体重、身高、BMI行回顾性相关分析显示:噪声与BMI呈较显著正相关且相关性最大,相关系数为0.557。A组噪声均值小于B组,但B组噪声均匀度好于A组。A组ED为(21.27±1.53)mSv,B组ED为(6.04±1.45)mSv,两组间剂量差异均有统计学意义(P<0.05)。两组之间图像质量无差异。结论在心率<70次/min且心律稳定时,BMI适应性电流、电压结合前置门控技术可以在提高图像噪声均匀度的同时降低ED 71.6%。
Objective To explore the feasibility of reducing body mass index (BTA) adaptive current and voltage combined with pre-gating in lowering the dose of coronary CT angiography (CCTA) and improving the uniformity of image noise. Materials and Methods 120 patients scheduled for CCTA examination were randomly divided into A and B groups. In group A, a retrospective ECG gating mode with fixed current and voltage was used. In group B, pre-ECG gating mode with BMI adaptive current and voltage was used to record patient’s height, weight, BMI, current, voltage and noise, CT dose index (CTDI), effective dose (ED) and so on. Image quality score using 4 points score. The data were processed by SPSS13.0 software. Results A retrospective analysis of image noise, weight, height and BMI in group A showed that there was a significant positive correlation between noise and BMI and the correlation was the highest, with a correlation coefficient of 0.557. The mean noise of group A is less than that of group B, but the noise uniformity of group B is better than that of group A. The ED in group A was (21.27 ± 1.53) mSv, and that in group B was (6.04 ± 1.45) mSv. There was significant difference in dose between the two groups (P <0.05). There was no difference in image quality between the two groups. Conclusion When heart rate is less than 70 beats / min and heart rate is stable, BMI adaptive current and voltage combined with pre-gating technique can reduce ED 71.6% while improving image noise uniformity.