Department of Diagnostic Radiology, San Gerardo Hospital, Monza, MB, Italy.
Department of Diagnostic Radiology, H Papa Giovanni XXIII, Bergamo, BG, Italy.
Br J Radiol. 2021 Aug 1;94(1124):20201223. doi: 10.1259/bjr.20201223. Epub 2021 Jul 8.
To compare image quality and radiation dose of CT images reconstructed with model-based iterative reconstruction (MBIR) and hybrid-iterative (HIR) algorithm in oncologic patients.
125 oncologic patients underwent both contrast-enhanced low- (100 kV), and standard (120 kV) dose CT, were enrolled. Image quality was assessed by using a 4-point Likert scale. CT attenuation values, expressed in Hounsfield unit (HU), were recorded within a regions of interest (ROI) of liver, spleen, paraspinal muscle, aortic lumen, and subcutaneous fat tissue. Image noise, expressed as standard deviation (SD), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were calculated. Radiation dose were analyzed. Paired Student's -test was used to compare all continuous variables.
The overall median score assessed as image quality for CT images with the MBIR algorithm was significantly higher in comparison with HIR [4 (range 3-4) 3 (3-4), = 0.017].CT attenuation values and SD were significantly higher and lower, respectively, in all anatomic districts in images reconstructed with MBIR in comparison with HIR ones (all < 0.001). SNR and CNR values were higher in CT images reconstructed with MBIR, reaching a significant difference in all districts (all < 0.001). Radiation dose were significantly lower in the MBIR group compared with the HIR group ( < 0.001).
MBIR combined with low-kV setting allows an important dose reduction in whole-body CT imaging, reaching a better image quality both qualitatively and quantitatively.
MBIR with low-dose approach allows a reduction of dose exposure, maintaining high image quality, especially in patients which deserve a longlasting follow-up.
比较基于模型的迭代重建（MBIR）和混合迭代（HIR）算法重建的 CT 图像在肿瘤患者中的图像质量和辐射剂量。
纳入 125 名接受对比增强低剂量（100kV）和标准剂量（120kV）CT 的肿瘤患者。使用 4 分制 Likert 量表评估图像质量。在肝、脾、椎旁肌肉、主动脉腔和皮下脂肪组织的感兴趣区域（ROI）内记录 CT 衰减值（以 Hounsfield 单位（HU）表示）。计算图像噪声（表示为标准差（SD））、信噪比（SNR）和对比噪声比（CNR）。分析辐射剂量。采用配对学生 t 检验比较所有连续变量。
总体中位数评分评估 MBIR 算法的 CT 图像质量明显高于 HIR [4（范围 3-4） 3（3-4）， = 0.017]。MBIR 重建的 CT 图像中所有解剖区的 CT 衰减值明显较高，SD 明显较低（均 < 0.001）。MBIR 重建的 CT 图像中 SNR 和 CNR 值较高，在所有区域均达到显著差异（均 < 0.001）。MBIR 组的辐射剂量明显低于 HIR 组（ < 0.001）。
MBIR 结合低 kV 设置可在全身 CT 成像中实现重要的剂量降低，在定性和定量方面均能达到更好的图像质量。
低剂量 MBIR 方法允许减少剂量暴露，同时保持高图像质量，特别是在需要长期随访的患者中。
