Department of Nuclear Medicine and Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital, No. 5 Fu-Shin Street, Kwei-Shan, Taoyuan County, Taiwan.
Siemens Shenzhen Magnetic Resonance Ltd. Siemens MR Center, Gaoxin C. Ave., 2nd, Hi-Tech Industrial Park, Shenzhen, 518057, P.R. China.
Magn Reson Med. 2017 Oct;78(4):1383-1391. doi: 10.1002/mrm.26528. Epub 2016 Oct 31.
Total variation (TV) method has been used widely for image restoration and reconstruction. In this work, we propose a TV-based algorithm for parametric image generation in intravoxel incoherent motion (IVIM) diffusion-weighted magnetic resonance imaging (DW-MRI).
We used simulated and real data to investigate whether the proposed TV-based method can provide reliable parametric images. Parametric images of IVIM parameters including perfusion fraction (PF), diffusion coefficient (D), and pseudo-diffusion coefficient (D*) were estimated using DW-MRI data and TV through fitting the IVIM model. The Levenberg-Marquardt (LM) method, which has often been used in the context of IVIM analysis, was employed as the standard method for comparison of the resulting parametric images.
The simulation results show that the proposed method outperforms the LM algorithm in terms of precision, providing a 40-81%, 90-93%, and 68-84% improvement for PF, D and D*, respectively, at signal-to-noise ratio (SNR) of 30. For real data, the proposed method showed an average five-fold, three-fold, and four-fold improvement in the SNR for PF, D and D*, respectively.
We introduced the use of TV to produce parametric images, and demonstrated that the proposed TV-based method is effective in improving the parametric image quality. Magn Reson Med 78:1383-1391, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
全变差（TV）方法已被广泛应用于图像恢复和重建。本研究提出了一种基于 TV 的算法，用于在体素内不相干运动（IVIM）扩散加权磁共振成像（DW-MRI）中生成参数图像。
我们使用模拟和真实数据来研究所提出的基于 TV 的方法是否可以提供可靠的参数图像。使用 DW-MRI 数据和 TV 通过拟合 IVIM 模型，估计 IVIM 参数的参数图像，包括灌注分数（PF）、扩散系数（D）和假性扩散系数（D*）。经常在 IVIM 分析中使用的 Levenberg-Marquardt（LM）方法被用作比较结果参数图像的标准方法。
模拟结果表明，与 LM 算法相比，该方法在精度方面表现更好，在信噪比（SNR）为 30 时，PF、D 和 D的精度分别提高了 40-81%、90-93%和 68-84%。对于真实数据，与 LM 算法相比，该方法在 SNR 方面，PF、D 和 D的平均改善倍数分别为 5 倍、3 倍和 4 倍。
我们引入了使用 TV 生成参数图像的方法，并证明了所提出的基于 TV 的方法在提高参数图像质量方面是有效的。磁共振医学 78:1383-1391, 2017。© 2016 国际磁共振学会。
