目的 探讨iDose4迭代重建技术 在心肌桥-壁冠状动脉复合体中的应用价 值。方法 选择60例心肌桥-壁冠状动脉 复合体患者为研究对象，其中30例接受 iDose4技术重建，30例患者接受FBP技术 重建。观察256层CT对心肌桥显示情况， 比较FBP技术和iDose4技术辐射剂量、 信号噪声比(signal to noise ratio, SNR)、对比度噪声比(contrast noise ratio, CNR)及图像质量评分。结果 256 层CT共显示检查心肌桥-壁冠状动脉复 合体114处，左前降支中段发病率最高 (59.61%)，右侧冠状动脉主干发病率最低 (1.75%)。心肌桥平均长度(17.2±2.7) mm，厚度(2.4±0.7)mm。iDose4技术辐 射剂量显著低于FBP技术，差异具有统 计学意义(P＜0.05)。iDose4技术SNR及 CNR均显著高于FBP技术，差异具有统计 学意义(P＜0.05)。但两种技术重建图像 质量评分间比较，差异无统计学意义(P ＞0.05)。结论 在壁冠状动脉显示中， iDose4重建技术可以在保证SNR、CNR及图 像质量的基础上降低辐射剂量，值得临床 推广应用。

Objective To explore the application value of iDose4 iterative reconstruction technique in myocardial bridge and mural coronary artery. Methods Sixty patients with myocardial bridge and mural coronary artery complex were chosen as the research object, 30 of them underwent iDose4 reconstruction technique and the rest underwent FBP reconstruction technique. The CT images of myocardial bridge were observed, the radiation dose, signal to noise ratio (SNR), contrast to noise ratio (CNR) and image quality score between FBP technology and iDose4 technology were compared. Results It showed 114 cases of myocardial bridge mural coronary artery complex, the incidence rate of left anterior descending branch is 59.61%, the incidence rate of right coronary artery is 1.75%. The average length of myocardial bridge were (17.2±2.7) mm, thickness was (2.4±0.7) mm. IDose4 radiation dose was significantly lower than that of FBP technology (P<0.05). The SNR and CNR of IDose4 were significantly higher than that of FBP (P<0.05). But the difference of two reconstruction image quality score had no statistical significance (P>0.05). Conclusion In the display of mural coronary artery, IDose4 reconstruction technique can reduce radiation dose on the basis of SNR, CNR and image quality, it is worthy of clinical popularization and application.