Density imaging using inverse scattering
Density imaging using inverse scattering
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DOI：
10.1121/1.3050249
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发表时间：
2009-02-01
影响因子：
2.4
通讯作者：
Oelze, Michael L.
中科院分区：
文献类型：
--
作者：
Lavarello, Roberto J.;Oelze, Michael L.
逆散射被认为是最稳健、最精确的超声层析成像方法之一。大多数逆散射公式忽略密度变化，以重建声速和声衰减。文献中的一些研究表明，密度分布也可以使用逆散射公式来恢复。已经确定了两类算法。(1)利用等密度反散射算法在多频率下分离声速和密度贡献。(2)含密度变化的全波方程反演。在这项工作中，研究了每一类具有代表性的算法在圆柱重建中的性能：双频畸变Born迭代法（DF-DBIM）和t矩阵公式。在密度变化适中的情况下，两种算法重构的圆柱体直径可达8个波长，均方根误差均小于30%。然而，为了提供准确的重建，DF-DBIM和t矩阵方法分别需要非常高的信噪比和非常大的带宽。这些限制将在实际实验实现的背景下讨论。(C) 2009美国声学学会。(DOI: 10.1121/1.3050249)
Inverse scattering is considered one of the most robust and accurate ultrasonic tomography methods. Most inverse scattering formulations neglect density changes in order to reconstruct sound speed and acoustic attenuation. Some studies available in literature suggest that density distributions can also be recovered using inverse scattering formulations. Two classes of algorithms have been identified. (1) The separation of sound speed and density contributions from reconstructions using constant density inverse scattering algorithms at multiple frequencies. (2) The inversion of the full wave equation including density changes. In this work, the performance of a representative algorithm for each class has been studied for the reconstruction of circular cylinders: the dual frequency distorted Born iterative method (DF-DBIM) and the T-matrix formulation. Root mean square error values lower than 30% were obtained with both algorithms when reconstructing cylinders up to eight wavelengths in diameter with moderate density changes. However, in order to provide accurate reconstructions the DF-DBIM and T-matrix method required very high signal-to-noise ratios and significantly large bandwidths, respectively. These limitations are discussed in the context of practical experimental implementations. (C) 2009 Acoustical Society of America. [DOI: 10.1121/1.3050249]