From the Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University Tuebingen, Tuebingen.
MR Applications Predevelopment, Siemens Healthcare GmbH, Erlangen, Germany.
Invest Radiol. 2021 Jul 1;56(7):465-470. doi: 10.1097/RLI.0000000000000761.
The aim of this study was to investigate the impact of a novel edge enhancement and iterative denoising algorithm in 1.5-T T1-weighted dynamic contrast-enhanced (DCE) gradient echo (GRE) magnetic resonance imaging of the abdomen on image quality, noise levels, diagnostic confidence, and lesion detectability.
Fifty patients who underwent a clinically indicated magnetic resonance imaging with DCE imaging of the abdomen between June and August 2020 were included in this retrospective, monocentric, institutional review board-approved study. For DCE imaging, a series of 3 volume interpolated breath-hold examinations (VIBEs) was performed. The raw data of all DCE imaging studies were processed twice, once using standard reconstruction (DCES) and again using an edge enhancement and iterative denoising approach (DCEDE). All imaging studies were randomly reviewed by 2 radiologists independently regarding noise levels, arterial contrast, sharpness of vessels, overall image quality, and diagnostic confidence using a Likert scale ranging from 1 to 4, with 4 being the best. Furthermore, lesion detectability was evaluated using the same ranking system.
All 50 imaging studies were successfully reconstructed with both methods. Interreader agreement (Cohen κ) was substantial to perfect for both readers. Arterial contrast and sharpness of vessels were rated superior by both readers with a median of 4 in DCEDE versus a median of 3 in DCES (P < 0.001). Furthermore, noise levels as well as overall image quality were rated higher with a median of 4 in DCEDE compared with a median of 3 in DCES (P < 0.001). Lesion detectability was evaluated to be superior in DCEDE with a median of 4 versus DCES with a median of 3 (P < 0.001). Consequently, diagnostic confidence was also rated to be superior in DCEDE with a median of 4 versus DCES with a median of 3 (P < 0.001).
Iterative denoising and edge enhancement are feasible in DCE imaging of the abdomen providing superior arterial contrast, noise levels, and overall image quality. Furthermore, lesion detectability and diagnostic confidence were significantly improved using this novel reconstruction method. Further reduction of acquisition time might be possible via reduction of increased noise levels using this presented method.
本研究旨在探讨一种新的边缘增强和迭代去噪算法在腹部 1.5-T T1 加权动态对比增强（DCE）梯度回波（GRE）磁共振成像中的应用对图像质量、噪声水平、诊断信心和病灶检出率的影响。
本回顾性、单中心、机构审查委员会批准的研究共纳入 2020 年 6 月至 8 月期间因临床需要行腹部磁共振成像（含 DCE 成像）的 50 例患者。DCE 成像采用一系列 3 容积内插屏气检查（VIBE）完成。所有 DCE 成像研究的原始数据均采用标准重建（DCES）和边缘增强迭代去噪法（DCEDE）各重建 1 次。由 2 名放射科医师对所有成像研究的噪声水平、动脉对比度、血管锐利度、整体图像质量和诊断信心进行随机回顾，采用 1-4 分的 Likert 评分系统进行评估，4 分为最佳。此外，还采用相同的评分系统评估病灶检出率。
两种方法均成功重建了所有 50 例成像研究。两名观察者之间的一致性（Cohen κ）均为强至极好。两名观察者均认为动脉对比度和血管锐利度在 DCEDE 重建中评分更高（中位数 4 分，DCES 重建中中位数 3 分；P＜0.001）。此外，DCEDE 重建的噪声水平和整体图像质量评分也更高（中位数 4 分，DCES 重建中中位数 3 分；P＜0.001）。DCEDE 重建的病灶检出率评分更高（中位数 4 分，DCES 重建中中位数 3 分；P＜0.001），诊断信心评分也更高（中位数 4 分，DCES 重建中中位数 3 分；P＜0.001）。
腹部 DCE 成像中迭代去噪和边缘增强是可行的，可提高动脉对比度、噪声水平和整体图像质量。此外，使用这种新的重建方法可显著提高病灶检出率和诊断信心。通过使用该方法降低增加的噪声水平，可能进一步缩短采集时间。
