第3代双源CT卷积核的选择对肺磨玻璃结节图像质量的影响

目的：探讨第3代双源CT卷积核的合理选择在横断面重建图像中对肺磨玻璃结节(ground-glass nodule，GGN)显示的价值。方法：纳入2018年2月至2019年1月期间，在中南大学湘雅二医院行肺部CT扫描发现肺GGN并手术证实为早期腺癌的患者52例，对其肺部CT数据进行卷积核Bl57，Br54，Br49的3组重建。以GGN处图像的信噪比(signal-to-noise ratio，SNR)、对比噪声比(contrast-to-noise ratio，CNR)和标准差(standard deviation，SD)作为客观图像质量评价标准，主观图像质量由2名放射科医生从总体图像质量、噪声、病变轮廓3个方面进行双盲评分。结果：重建卷积核Br49(SNR：11.36±5.39，CNR：7.19±4.29)，Br54(SNR：8.30±3.35，CNR：5.09±2.86)图像的SNR和CNR明显高于重建卷积核Bl57图像(SNR：4.18±2.10，CNR：3.25±1.78；多重比较均P<0.01)。GGN处SD重建卷积核Br49为61.80±20.17，Br54为80.45±20.31，均明显低于重建卷积核Bl57(137.92±31.11，均P<0.01)。总体图像质量方面，重建卷积核Br54评分5.0(4.5, 5.0)，高于重建卷积核Br49评分3.0(3.0, 4.0)，Br49评分高于Bl57评分3.0(3.0, 3.5)(均P<0.05)；病灶轮廓方面，重建卷积核Br54评分5.0(4.0, 5.0)，高于重建卷积核Br49评分4.0(4.0, 5.0)，Br49图像评分高于Bl57评分3.0(3.0, 3.0)(均P<0.05)；图像噪声方面，卷积核Br49评分3.0(3.0, 3.0)，低于重建卷积核Br54评分4.0(4.0, 4.0)，Br54评分低于Bl57评分5.0(5.0, 5.0)(均P<0.05)。结论：CT卷积核的合理选择对GGN的主观和客观图像质量具有重要作用，建议使用Br54作为肺GGN重建卷积核，这将为医生找寻、诊断GGN提供帮助。

Impact of optional reconstruction kernel on image quality of pulmonary ground glass nodules using the third generation dual-source computed tomography

Objective: To explore the value of the third generation dual-source computed tomography (CT)convolution kernel in display of pulmonary ground-glass nodule (GGN) in transverse imagereconstruction.Methods: A total of 52 lung adenocarcinoma patients with lung CT data were selected fromFebruary 2018 to January 2019 for this study. The pulmonary CT data were reconstructed byconvolutional nucleus B157, Br54, and Br49. The signal-to-noise ratio (SNR), the contrast-to-noiseratio (CNR), and the standard deviation (SD) of the image at the GGN were used as the objectiveevaluation standard of image quality. Subjective image quality was scored by 2 radiologists from 3aspects (overall image quality, noise, and lesion outline).Results: Objective image quality evaluation, SNR and CNR of reconstructed convolution kernelBr49 (SNR: 11.36±5.39, CNR: 7.19±4.29), Br54 (SNR: 8.30±3.35, CNR: 5.09±2.86) are greaterthan those of Bl57 (SNR: 4.18±2.10, CNR: 3.25±1.78; all P<0.01). SD of reconstructed convolutionkernel Br49 (61.80±20.17) and Br54 (80.45±20.31) is smaller than that of Bl57 (137.92±31.11,both P<0.01). In the subjective image quality evaluation, the overall image quality score 5.0(4.5,5.0) of Br54 was higher than that of all other images [Br49: 3.0(3.0, 4.0), Bl57: 3.0(3.0, 3.5); bothP<0.05]. The Br54 image showed that the lesion contour ability score 5.0(4.0, 5.0) was higher thanall other images [Br49: 4.0(4.0, 5.0), Bl57: 3.0(3.0, 3.0); both P<0.05]; Br49 image noise score3.0(3.0, 3.0) is the lowest one [Br54 4.0(4.0, 4.0), Bl57 5.0(5.0, 5.0); both P<0.05].Conclusion: The reasonable selection of CT convolution kernel plays an important role in thesubjective and objective image quality of GGN. It is suggested that Br54 should be used as thereconstruction of convolutional kernel in pulmonary ground glass nodules, which is helpful fordoctors to find and diagnose GGN.