小儿心脏双源CT图像质量和辐射剂量多模态对比研究

摘要

目的：探讨在小儿心脏CT冠状动脉造影（ CTA）成像中，双源CT的前瞻性心电门控模式和大螺距Flash模式在成像质量和辐射剂量方面的差异。方法从2014年12月～2015年5月疑似先天性心脏病的小儿患者中，选出两组不同检查模式（ Prospect组和Flash组）的病例，每组30例。两名医师组成共识小组，对图像质量进行5级评分，同时比较两组的CT容积剂量指数（CTDIvol）、剂量长度乘积（DLP）。结果 Prospect组和Flash组的CTDIvol分别为（1．35±0．06） mGy和（3．02±0．17）mGy；两组的DLP分别为（28．3±1．6）mGy・ cm和（67．8±3．8）mGy・ cm。两位评价者在所有患者的图像评价中均最终达成一致结果，所有患者的图像评分均达到了3分以上即均达到诊断要求。结论两种模式的图像质量在诊断儿童先天性心脏病上无明显差异。而前瞻性心电门控模式的辐射剂量要大于Flash模式。双源CTA的Flash模式在小儿心脏检查中具有良好的应用价值。%Objective To compare radiation dose and image quality of different CTA modes for children with complex congeni -tal heart disease .Methods We retrospectively assembled two cohorts from 80 infants who underwent heart CTA from August 2014 to January 2013 with different protocol , each containing 30 patients .Two radiologists assessed image quality with 5-piont scale subjectively.Radiation dose parameters (CTDIvol and DLP) were compared.Results Mean CTDIvol and DLP were 93.02 ±0.17) mGy and (67.8 ±3.8) mGy・ cm for Flash mode, (1.35 ±0.06) mGy and (28.3 ±1.6) mGy・ cm for prospective ECG-triggering mode.Image quality indicated no difference between groups ( Z =-0.403, P =0.715).Conclusion Compared with Flash mode, prospective ECG-triggering mode has the same good image quality for infant cardiac dual-source CT angiogra-phy, meanwhile radiation dose is significantly lower with prospective ECG-triggering mode.