Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, South Korea.
Magn Reson Med. 2020 Mar;83(3):858-871. doi: 10.1002/mrm.27976. Epub 2019 Aug 29.
Quantitative susceptibility mapping (QSM) inevitably suffers from streaking artifacts caused by zeros on the conical surface of the dipole kernel in k-space. This work proposes a novel and accurate QSM reconstruction method based on k-space low-rank Hankel matrix constraint, avoiding the over-smoothing problem and streaking artifacts.
Based on the recent theory of annihilating filter-based low-rank Hankel matrix approach (ALOHA), QSM is formulated as deconvolution under low-rank Hankel matrix constraint in the k-space. The computational complexity and the high memory burden were reduced by successive reconstruction of 2-D planes along 3 independent axes of the 3-D phase image in Fourier domain. Feasibility of the proposed method was tested on a simulated phantom and human data and were compared with existing QSM reconstruction methods.
The proposed ALOHA-QSM effectively reduced streaking artifacts and accurately estimated susceptibility values in deep gray matter structures, compared to the existing QSM methods.
The suggested ALOHA-QSM algorithm successfully solves the 3-dimensional QSM dipole inversion problem using k-space low rank property with no anatomical constraint. ALOHA-QSM can provide detailed brain structures and accurate susceptibility values with no streaking artifacts.
定量磁化率映射(QSM)不可避免地会受到在k 空间中的偶极核圆锥面上的零值引起的条纹伪影的影响。本研究提出了一种基于 k 空间低秩汉克尔矩阵约束的新颖且精确的 QSM 重建方法,避免了过度平滑问题和条纹伪影。
基于最近的基于湮灭滤波器的低秩汉克尔矩阵方法(ALOHA)理论,QSM 被表述为在 k 空间中基于低秩汉克尔矩阵约束的反卷积。通过沿三维相位图像的三个独立轴逐次重建二维平面,降低了计算复杂度和高内存负担。在模拟体模和人体数据上测试了所提出方法的可行性,并与现有的 QSM 重建方法进行了比较。
与现有的 QSM 方法相比,所提出的 ALOHA-QSM 有效地减少了条纹伪影并准确估计了深部灰质结构中的磁化率值。
所提出的 ALOHA-QSM 算法成功地利用 k 空间的低秩特性解决了三维 QSM 偶极子反演问题,无需解剖约束。ALOHA-QSM 可以提供无条纹伪影的详细脑结构和准确的磁化率值。