Matsuda Megumi, Tsuda Takaharu, Kido Teruhito, Tanaka Hiroaki, Nishiyama Hikaru, Itoh Toshihide, Nakao Kenichi, Hirooka Masashi, Mochizuki Teruhito
CT Research and Collaboration, Siemens Healthcare, Gate City Osaki West Tower, Osaki, Shinagawaku, Tokyo.
Department of Gastroenterology and Metabology, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, Japan.
J Comput Assist Tomogr. 2018 Nov/Dec;42(6):937-943. doi: 10.1097/RCT.0000000000000752.
This study aimed to evaluate the utility of virtual monoenergetic images for detecting washout of small (≤2 cm) hepatocellular carcinoma (HCC) in the equilibrium phase.
We performed 120-kVp-equivalent linear-blended (M120) and monoenergetic reconstructions from 40 to 90 keV by standard (40, 50, 60, 70, 80, 90) and novel noise-reduced (nMERA: 40+, 50+, 60+, 70+, 80+, 90+) monoenergetic reconstruction algorithms. Image quality and tumor visibility of delayed washout of HCCs in the equilibrium phase were compared between standard monoenergetic reconstruction algorithm and nMERA by objective and subjective analyses.
Contrast-to-noise ratio of the tumor at 40+ was the highest, whereas the score of tumor visibility peaked at 50+. The score of overall image quality at 40+ was significantly lower than those on all other image series, and the image quality among other image series were not significantly different.
Virtual monoenergetic image reconstructed with nMERA 50+ was most appropriate to detect washout of small HCCs.
本研究旨在评估虚拟单能图像在检测平衡期小（≤2 cm）肝细胞癌（HCC）洗脱方面的效用。
我们通过标准（40、50、60、70、80、90）和新型降噪（nMERA：40 +、50 +、60 +、70 +、80 +、90 +）单能重建算法进行了120 kVp等效线性混合（M120）和40至90 keV的单能重建。通过客观和主观分析，比较了标准单能重建算法和nMERA在平衡期HCC延迟洗脱的图像质量和肿瘤可见性。
40 +时肿瘤的对比噪声比最高，而肿瘤可见性评分在50 +时达到峰值。40 +时的整体图像质量评分明显低于所有其他图像系列，其他图像系列之间的图像质量无明显差异。
用nMERA 50 +重建的虚拟单能图像最适合检测小HCC的洗脱。
