摘要
目的分析低电压、低浓度对比剂(双低)宝石CT冠状动脉成像的图像质量、辐射剂量,探讨双低扫描在宝石CT冠状动脉成像的可行性。方法纳入2014年1月-3月因怀疑冠状动脉病变行冠状动脉CT血管成像检查的69例患者,将患者随机分为双低组和常规组。双低组34例行双低扫描,对比剂碘浓度为300 mg/m L,管电压100 k V;常规组35例行常规扫描,对比剂碘浓度为370 mg/m L,管电压120 k V。按美国心脏协会冠状动脉改良分段法评价各段及各分支的图像质量。测量升主动脉、左冠状动脉主干及左前降支、左旋支、右冠状动脉近段管腔的CT值及其邻近组织的CT值。记录CT容积剂量指数(CTDIvol)和剂量长度乘积(DLP),计算有效辐射剂量(ED)。结果两组扫描时平均心率、扫描范围比较差异无统计学意义(P>0.05)。双低组患者的CTDIvol、ED较常规组明显降低(P<0.05)。两组患者图像质量的客观评分比较差异无统计学意义(P>0.05)。双低组患者的升主动脉CT值以及左冠状动脉主干(LM)、左前降支(LAD)、左旋支(LCX)、右冠状动脉(RCA)近段管腔的CT值明显高于常规组,双低组的图像噪声明显高于常规组,两组比较差异均有统计学意义(P<0.05)。两组LM、LAD、LCX、RCA近段管腔的信噪比、对比噪声比比较差异无统计学意义(P>0.05)。结论 100 k V联合低浓度对比剂(碘浓度300 mg/m L)不仅能保证图像质量满足诊断要求,同时还可减少辐射剂量和碘注入量。
Objective To assess the image quality and radiation dose of gemstone CT coronary angiography（CCTA） with low tube voltage and low concentration contrast medium. Methods Sixty-nine patients who underwent CCTA from January to March 2014 were randomly divided into group A and B. CCTA was performed in thirty-four patients in group A with tube voltage of 100 k V and concentration of contrast medium of 300 mg I/m L. And thirty-five patients in group B underwent CCTA with 120 k V and 370 mg I/m L. According to upgrading American Heart Association standard all segments and all vessels were evaluated. We measured the CT value of ascending aortic root, left main coronary artery, and the initial segment of left anterior descending branch, left circumflex, right coronary artery, and also adjacent tissues. Besides, we recorded CT dose volume index（CTDIvol） and the dose length product（DLP） and calculated effective radiation dose. Results The image quality scores were not significantly different between two groups（P〉 0.05）. The density in the contrast enhanced vessel lumens in group A were signifcantly higher than that in group B（P〉 0.05）. There was no significant difference in signal to noise ratio and carrier to noise ratio between the two groups（P〈 0.05）. Noise in group A was higher than that in group B（P〈 0.05）. The CTDIvol and effective radiation dose in group A were significantly lower than those in group B（P〈 0.05）. Conclusions The combination of 100 k V with low concentration contrast medium（300 mg I/m L） still maintains the image quality, as well as significantly lowers the radiation dose and the dose of iodine.
出处
《华西医学》
CAS
2015年第11期2085-2089,共5页
West China Medical Journal
关键词
冠状动脉
管电压
对比剂浓度
辐射剂量
Coronary artery
Tube voltage
Contrast medium concentration
Radiation dose
