双源CT前瞻性心电门控技术在婴幼儿先天性心脏病的成像研究

目的通过对选用前瞻性心电门控扫描技术与回顾性心电门控扫描技术所得到的图像质量和放射剂量的对照研究，探讨双源CT（DSCT）前瞻性心电门控低剂量技术应用于婴幼儿先天性心脏病成像的可行性。方法连续搜集90例临床拟行双源CT胸部大血管检查的婴幼儿患者。随机分为两组，A组（45例）选用前瞻性心电门控扫描模式扫描。B组（45例）采用回顾性心电门控扫描模式扫描。由2名高年资的诊断医师以双盲法分别对A、B组图像进行图像质量评价，两组间图像质量差异用两独立样本Wilcoxon秩和检验进行分析。两组图像图像噪声、辐射剂量参数CTDI、DLP和ED差异用两独立样本均数f检验进行比较。结果A、B两组图像质量差异无统计学意义（H=O．098，P〉0．05）；A、13两组噪声值分别为（13．25±1．27）HU，（13．51±1．41）HU，两组间噪声值差异无统计学意义（t=0．925，P〉0．05）；A、B两组CTDI、DLP、ED分别为（2．70±0．75）mGy、（29．55±10．17）mGy／cm、（0．41±0．14）mSv；（3．81±1．03）mGy、（51．57±14．81）mGy／cm、（O．72±0．20）mSv；A组CTDI、DLP、ED明显低于B组，2组差异有统计学意义（t=5．36，8．13，8．13，P=0．001）。结论双源CT婴幼儿先天性心脏病成像时使用前瞻性心电门控扫描可以有效地减少受检者接受的x射线剂量，同时可以保证图像质量。

The feasibility of prospective electrocardiogram dual-source CT in infants with eongential heart disease

Objective To compare radiation dose and image quality between prospective and retrospective ECG gating CT cardiac angiography （CTCA） with dual-source computed tomography （DSCT） CT scanner. Methods Ninety patiens with suspected congenital heart disease were selected, and randomly devided into two groups. Group A underwent CTA using prospective ECG-gating, while, group B underwent CTA using retrospective ECCgating. Two doctors with high qualifi- cation diagosed respectively on the image quality doule-blindly. Image quality differences between the two groups were e- valuated with two independent sample Wilcoxon rank and inspection test. Two groups of the dose radiation parameters such as CTDI, DLP, and ED differences were evaluated with Student＇s test. Results There were no statistical difference in image quality between group A, B （ H --0. 098, P 〉0.05）. The nosie measurements for roup A, B were （13. 25±1.27） HU, （13.51±1.41） HU, respectively, with t-test of P 〉0.05 indicating no statistical difference. In addition, the CTDI, DLP, Effective dose values were （2.70±0.75） mGY, （29.55±10. 17） mGy/cm, （0.41±0.14） mSv; （3.81± 1.03） mGY, （51.57±14.81） mGy/cm, （0.72±0.20） mSv, respectively, with t test of P〈0.05 with indicating statisti- cally significant lower dosagewith pros-pective ECG gating CTA. Conclusion Prospective ECG gating CTA can effectively reduce the infant＇s radiation dose without compromising image quality.