Department of Radiology, Charité Universitätsmedizin Berlin, Berlin, Germany.
Department of Nuclear Medicine, Charité Universitätsmedizin Berlin, Berlin, Germany.
Magn Reson Med. 2019 Nov;82(5):1753-1766. doi: 10.1002/mrm.27867. Epub 2019 Jun 22.
To provide nonrigid respiratory motion-corrected DCE-MRI images with isotropic resolution of 1.5 mm, full coverage of abdomen, and covering the entire uptake curve with a temporal resolution of 6 seconds, for the quantitative assessment of hepatic lesions.
3D DCE-MRI data were acquired at 3 T during free breathing for 5 minutes using a 3D T -weighted golden-angle radial phase-encoding sequence. Nonrigid respiratory motion information was extracted and used in motion-corrected image reconstruction to obtain high-quality DCE-MRI images with temporal resolution of 6 seconds and isotropic resolution of 1.5 mm. An extended Tofts model was fitted to the dynamic data sets, yielding quantitative parametric maps of endothelial permeability using the hepatic artery as input function. The proposed approach was evaluated in 11 patients (52 ± 17 years, 5 men) with and without known hepatic lesions, undergoing DCE-MRI.
Respiratory motion produced artifacts and misalignment between dynamic volumes (lesion average motion amplitude of 3.82 ± 1.11 mm). Motion correction minimized artifacts and improved average contrast-to-noise ratio of hepatic lesions in late phase by 47% (p < .01). Quantitative endothelial permeability maps of motion-corrected data demonstrated enhanced visibility of different pathologies (e.g., metastases, hemangiomas, cysts, necrotic tumor substructure) and showed improved contrast-to-noise ratio by 62% (p < .01) compared with uncorrected data.
3D nonrigid motion correction in DCE-MRI improves both visual and quantitative assessment of hepatic lesions by ensuring accurate alignment between 3D DCE images and reducing motion blurring. This approach does not require breath-holds and minimizes scan planning by using a large FOV with isotropic resolution.
提供具有各向同性分辨率 1.5 毫米、腹部完全覆盖和 6 秒时间分辨率的非刚性呼吸运动校正 DCE-MRI 图像，用于肝病变的定量评估。
在 3T 下使用 3D T1 加权黄金角径向相位编码序列在自由呼吸期间采集 5 分钟的 3D DCE-MRI 数据。提取非刚性呼吸运动信息并用于运动校正图像重建，以获得具有 6 秒时间分辨率和 1.5 毫米各向同性分辨率的高质量 DCE-MRI 图像。将扩展的 Tofts 模型拟合到动态数据集，使用肝动脉作为输入函数生成内皮通透性的定量参数图。在 11 名（52 ± 17 岁，5 名男性）已知肝病变和无肝病变的患者中评估了所提出的方法，进行 DCE-MRI。
呼吸运动产生了伪影并导致动态容积之间的错位（病变平均运动幅度为 3.82 ± 1.11 毫米）。运动校正最小化了伪影并将晚期肝病变的平均对比噪声比提高了 47%（p <.01）。运动校正数据的定量内皮通透性图增强了不同病变（例如转移瘤、血管瘤、囊肿、坏死肿瘤亚结构）的可见性，并将对比噪声比提高了 62%（p <.01）与未校正数据相比。
DCE-MRI 中的 3D 非刚性运动校正通过确保 3D DCE 图像之间的准确对准并减少运动模糊，改善了肝病变的视觉和定量评估。该方法不需要屏气，并通过使用具有各向同性分辨率的大视野最小化扫描计划。
