Tatsugami Fuminari, Higaki Toru, Kawashita Ikuo, Fujioka Chikako, Nakamura Yuko, Takahashi Shinya, Awai Kazuo
Department of Diagnostic Radiology, Hiroshima University, Hiroshima, Japan.
Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima City, Hiroshima, Japan.
Acta Radiol. 2024 Dec;65(12):1569-1575. doi: 10.1177/02841851241288507. Epub 2024 Oct 22.
Low-keV virtual monoenergetic images (VMIs) of dual-energy computed tomography (CT) enhances iodine contrast for detecting small arteries like the Adamkiewicz artery (AKA), but image noise can be problematic. Deep-learning image reconstruction (DLIR) effectively reduces noise without sacrificing image quality.
To evaluate whether DLIR on low-keV VMIs of dual-energy CT scans improves the visualization of the AKA.
We enrolled 29 patients who underwent CT angiography before aortic repair. VMIs obtained at 70 and 40 keV were reconstructed using hybrid iterative reconstruction (HIR), and 40 keV VMIs were reconstructed using DLIR. The image noise of the spinal cord, the maximum CT values of the anterior spinal artery (ASA), and the contrast-to-noise ratio (CNR) of the ASA were compared. The overall image quality and the delineation of the AKA were evaluated on a 4-point score (1 = poor, 4 = excellent).
The mean image noise of the spinal cord was significantly lower on 40-keV DLIR than on 40-keV HIR scans; they were significantly higher than on 70-keV HIR images. The CNR of the ASA was highest on the 40-keV DLIR images among the three reconstruction images. The mean image quality scores for 40-keV DLIR and 70-keV HIR scans were comparable, and higher than of 40-keV HIR images. The mean delineation scores for 40-keV HIR and 40-keV DLIR scans were significantly higher than for 70-keV HIR images.
Visualization of the AKA was significantly better on low-keV VMIs subjected to DLIR than conventional HIR images.
双能计算机断层扫描（CT）的低keV虚拟单能图像（VMI）可增强碘对比度，用于检测诸如Adamkiewicz动脉（AKA）等小动脉，但图像噪声可能会成为问题。深度学习图像重建（DLIR）可有效降低噪声而不牺牲图像质量。
评估双能CT扫描的低keV VMI上的DLIR是否能改善AKA的可视化。
我们纳入了29例在主动脉修复术前接受CT血管造影的患者。使用混合迭代重建（HIR）重建70和40 keV时获得的VMI，使用DLIR重建40 keV的VMI。比较脊髓的图像噪声、脊髓前动脉（ASA）的最大CT值以及ASA的对比噪声比（CNR）。根据4分制（1 =差，4 =优）评估整体图像质量和AKA的清晰度。
40 keV DLIR扫描时脊髓的平均图像噪声显著低于40 keV HIR扫描；它们显著高于70 keV HIR图像。在三种重建图像中，40 keV DLIR图像上ASA的CNR最高。40 keV DLIR和70 keV HIR扫描的平均图像质量得分相当，且高于40 keV HIR图像。40 keV HIR和40 keV DLIR扫描的平均清晰度得分显著高于70 keV HIR图像。
与传统HIR图像相比，DLIR处理的低keV VMI上AKA的可视化明显更好。
