摘要
目的探讨超低剂量CT肺动脉成像(CTPA)联合深度学习重建(DLR)诊断肺栓塞(PE)的可行性。方法该研究为横断面研究。前瞻性纳入2024年4至7月复旦大学附属中山医院及上海市老年医学中心疑似PE行CTPA检查的患者100例,并根据区组随机化分为常规剂量组(RD组)和超低剂量组(ULD组),计算有效辐射剂量。RD组与ULD组的噪声指数分别设置为10和20,余扫描参数及对比剂注射方案均相同。RD组图像采用混合迭代算法(HIR)重建,ULD组图像分别采用HIR和深度学习重建(DLR)(ULD-HIR亚组、ULD-DLR亚组)。分别对3组图像的图像质量进行主观评价(总体图像噪声、肺动脉显示)和客观评价[图像的信噪比(SNR)、对比噪声比(CNR)]。最后以3名主任医师成立的专家委员会对PE的诊断结果作为金标准,由1名资质较低医师对3组图像的PE诊断率进行独立评估。3组间客观图像质量指标的比较采用单因素方差分析,进一步两两比较采用LSD事后检验;主观评分的比较采用Kruskal-Wallis H检验和Bonferroni法对多重比较结果进行校正。结果RD组与ULD组有效辐射剂量分别为(2.7±0.5)mSv、(0.7±0.2)mSv,差异有统计学意义(t=26.42,P<0.001)。RD组、ULD-HIR亚组及ULD-DLR亚组图像中的各级肺动脉CT值总体差异均无统计学意义(P>0.05)。RD组、ULD-HIR亚组及ULD-DLR亚组各级肺动脉的SNR和CNR总体差异有统计学意义(P<0.001),其中除RD组与ULD-HIR亚组左肺动脉干CNR、SNR值,左肺下叶基底段肺动脉的SNR值差异无统计学意义外(P>0.05),其余指标在组间两两比较中差异均有统计学意义(P<0.05)。RD组、ULD-HIR亚组和ULD-DLR亚组图像肺动脉显示、图像噪声主观评分总体差异有统计学意义(P<0.001),其中ULD-DLR亚组与RD组比较图像肺动脉显示主观评分差异无统计学意义(P>0.05),其余指标在组间两两比较差异均有统计学意义(P<0.05)。RD组、ULD-HIR亚组和ULD-DLR亚组图像在肺动脉主干、叶级及段级PE的诊断率差异无统计学意义(P>0.05)。结论DLR能显著降低CTPA检查的辐射剂量,即使在超低辐射剂量情况下,其图像质量仍优于常规剂量下使用HIR重建的图像,且不影响叶级及段级的PE诊断。
Objective To investigate the feasibility of ultra-low dose(ULD)CT pulmonary angiography(CTPA)combined with deep learning reconstruction(DLR)in the diagnosis of pulmonary embolism(PE).Methods This cross-sectional study prospectively enrolled 100 patients with suspected PE who underwent CTPA examination in Zhongshan Hospital Fudan University,and Shanghai Geriatric Medical Center from April to July 2024,and were randomly divided into the routine dose(RD)group and ULD group according to block randomization.Effective dose(ED)were calculated.The noise index of RD group and ULD group was set to 10 and 20,respectively.Other scanning parameters and contrast agent injection protocol were the same.The CT images of RD group were reconstructed using hybrid iterative reconstruction(HIR),while ULD images were reconstructed with HIR and DLR(ULD-HIR subgroup and ULD-DLR subgroup).The image quality of the three groups of images was subjectively evaluated(overall image noise,pulmonary artery display)and objectively evaluated[signal-to-noise ratio(SNR),contrast-to-noise ratio(CNR)of the images]respectively.Finally,the diagnostic results of PE by the expert committee composed of three chief physicians were taken as the gold standard,and one physician with lower qualifications independently evaluated the diagnostic rate of PE in the three groups of images.Objective image quality parameters across the three groups were compared using ANOVA,with LSD post hoc test was used for multiple comparisons.Subjective scores among the three groups were analyzed using the Kruskal-Wallis H test,with Bonferroni corrected pairwise post hoc test was applied for multiple pairwise comparisons.Results The ED in the RD group and ULD group were(2.7±0.5)mSv and(0.7±0.2)mSv,respectively,and the differences were statistically significant(t=26.42,P<0.001).The overall differences in CT values of pulmonary arteries at all levels in the images of the RD group,the ULD-HIR subgroup,and the ULD-DLR subgroup were not statistically significant(P>0.05).The RD group,ULD-HIR subgroup and ULD-DLR subgroup overall differences in SNR and CNR at all levels pulmonary arteries were statistically significant(P<0.001),in which except for the differences in CNR and SNR values of the left pulmonary arterial trunk in the RD group and the ULD-HIR subgroup,and SNR values of basal segment pulmonary artery of the lower lobe of the left lung,which were not statistically significant(P>0.05),the differences of the rest of the indexes in the pairwise comparisons between the groups were statistically significant(P<0.05).The overall differences in the subjective scores of image pulmonary vascular display and image noise in the RD group,ULD-HIR subgroup and ULD-DLR subgroup were statistically significant(P<0.001),except that the differences in the subjective scores of image pulmonary vascular display in the ULD-DLR subgroup were not statistically significant when compared with that of the RD group(P>0.05)and that of the rest of the metrics in the between-groups two-by-two comparisons were all statistically significant(P<0.05).The difference in diagnostic rates of PE in the pulmonary artery trunk,lobe and segmental levels in the images of the RD group,ULD-HIR subgroup and ULD-DLR subgroup was not statistically significant(P>0.05).Conclusions DLR can significantly reduce the radiation dose of CTPA examination.Even at ultra-low radiation dose,its image quality is still better than HIR reconstruction at conventional doses and preserve diagnostic accuracy of PE at the lobe level and segment level.
作者
陆金娟
沈蕾蕾
毕正宏
周淳
郭怡菁
徐伟健
叶晓丹
曾蒙苏
王明亮
Lu Jinjuan;Shen Leilei;Bi Zhenghong;Zhou Chun;Guo Yijing;Xu Weijian;Ye Xiaodan;Zeng Mengsu;Wang Mingliang(Department of Radiology,Shanghai Geriatric Medical Center(Zhongshan Hospital Fudan University Minhang Campus),Shanghai 201100,China;Department of Radiology,Zhongshan Hospital,Fudan University,Shanghai 200030,China)
出处
《中华放射学杂志》
北大核心
2025年第8期886-893,共8页
Chinese Journal of Radiology
基金
国家自然科学基金(82071990)
上海市抗癌协会“雏鹰”计划(SACA CY22C15)。
关键词
肺栓塞
深度学习重建
CT血管造影
辐射剂量
图像质量
Pulmonary embolism
Deep learning reconstruction
CT angiography
Radiation dose
Image quality
