Hamasaki Hiroshi, Shirasaka Takashi, Ushijima Yasuhiro, Akamine Hiroshi, Takayama Yukihisa, Kubo Yuichiro, Ishimatsu Keisuke, Nishie Akihiro, Kato Toyoyuki
Division of Radiology, Department of Medical Technology, Kyushu University Hospital, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
J Belg Soc Radiol. 2021 Sep 14;105(1):43. doi: 10.5334/jbsr.2444. eCollection 2021.
In CT during hepatic arteriography (CTHA), the addition of a noise power spectrum (NPS) model to conventional hybrid iterative reconstruction (HIR) may improve spatial resolution and reduce image noise. This study aims at assessing the image quality provided by HIR with a NPS model at CTHA.
This institutional review board-approved retrospective analysis included 26 patients with hepatocellular carcinomas (HCCs) who underwent CTHA. In all acquisitions, images were reconstructed with filtered back projection (FBP), adaptive iterative dose reduction 3D (AIDR), and AIDR enhanced (eAIDR) with the NPS model. Four radiologists analyzed the signal-to-noise ratio (SNR) of HCC nodules and its associated feeding arteries. The radiologists used a semiquantitative scale (-3 to +3) to rate the subjective image quality comparing both the FBP and eAIDR images with the AIDR images.
The feeding arteries' attenuation was significantly higher in eAIDR compared to AIDR [514.3 ± 121.4 and 448.3 ± 107.3 Hounsfield units (HU), p < 0.05]. The image noise of eAIDR was significantly lower than that of FBP (15.2 ± 2.2 and 28.5 ± 4.8 HU, p < 0.05) and comparable to that of AIDR. The SNR of feeding arteries on eAIDR was significantly higher than on AIDR (34.1 ± 7.9 and 27.4 ± 6.3, p < 0.05). Subjective assessment scores showed that eAIDR provided better visibility of feeding arteries and overall image quality compared to AIDR (p < 0.05). The HCC nodule visibility was not significantly different among the three reconstructions.
In CTHA, eAIDR improved the visibility of feeding arteries associated with HCC nodules without compromising nodule detection.
在肝动脉造影CT（CTHA）中，将噪声功率谱（NPS）模型添加到传统的混合迭代重建（HIR）中可能会提高空间分辨率并降低图像噪声。本研究旨在评估CTHA中使用NPS模型的HIR所提供的图像质量。
这项经机构审查委员会批准的回顾性分析纳入了26例接受CTHA的肝细胞癌（HCC）患者。在所有采集过程中，图像均采用滤波反投影（FBP）、自适应迭代剂量降低3D（AIDR）以及带有NPS模型的AIDR增强（eAIDR）进行重建。四名放射科医生分析了HCC结节及其相关供血动脉的信噪比（SNR）。放射科医生使用半定量量表（-3至+3）对主观图像质量进行评分，将FBP和eAIDR图像与AIDR图像进行比较。
与AIDR相比，eAIDR中供血动脉的衰减明显更高[514.3±121.4和448.3±107.3亨氏单位（HU），p<0.05]。eAIDR的图像噪声明显低于FBP（15.2±2.2和28.5±4.8 HU，p<0.05），与AIDR相当。eAIDR上供血动脉的SNR明显高于AIDR（34.1±7.9和27.4±6.3，p<0.05）。主观评估得分显示，与AIDR相比，eAIDR提供了更好的供血动脉可见性和整体图像质量（p<0.05）。三种重建方法之间HCC结节的可见性没有显著差异。
在CTHA中，eAIDR提高了与HCC结节相关的供血动脉的可见性，而不影响结节的检测。
