Quantitative photoacoustic image reconstruction for molecular imaging
Quantitative photoacoustic image reconstruction for molecular imaging
复制标题
分子成像的定量光声图像重建
DOI：
10.1117/12.644806
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
P. Beard
中科院分区：
文献类型：
--
作者：
Benjamin T Cox;S. Arridge;P. Beard
生物医学光声成像在短激光脉冲后产生组织中初始声压分布或吸收能量密度的图。定量光声成像（QPI）将重建过程进一步推进一步，以产生组织光学系数图。这有两个重要的优点。首先，它消除了内部光分布对图像对比度的畸变影响。其次，通过获得多个波长的图像，它使标准光谱技术能够用于量化特定发色团的浓度，例如，用于测量血液氧合的氧和脱氧血红蛋白——由于不同组织发色团之间的光谱“空间串音”效应，将此类技术直接应用于“常规”重建的吸收能量图是有问题的。与自然发生的发色团一样，染料标记的分子标记物也可用于标记特定分子，如细胞表面受体、酶或药物制剂。在QPI中，采用δ-Eddington散射系数拟合光在散射介质中输运的基于扩散的有限元模型来估计吸收能量分布的光学系数图。本文描述的方法使用递归算法，当散射已知时，可以快速收敛于吸收系数分布。通过增加已知的吸收面积，也可以得到未知的常数散射系数。利用这种方法估计的光学系数图，QPI有可能成为光声分子成像中定量分子标记物浓度的有力工具。
Biomedical photoacoustic imaging produces a map of the initial acoustic pressure distribution, or absorbed energy density, in tissue following a short laser pulse. Quantitative photoacoustic imaging (QPI) takes the reconstruction process one stage further to produce a map of the tissue optical coefficients. This has two important advantages. Firstly, it removes the distorting effect of the internal light distribution on image contrast. Secondly, by obtaining images at multiple wavelengths, it enables standard spectroscopic techniques to be used to quantify the concentrations of specific chromophores, for instance, oxy and deoxy haemoglobin for the measurement of blood oxygenation - applying such techniques directly to "conventionally" reconstructed absorbed energy maps is problematic due to the spectroscopic 'spatial crosstalk' effects between different tissue chromophores. As well as naturally-occurring chromophores, dye-labelled molecular markers can be used to tag specific molecules, such as cell surface receptors, enzymes or pharmaceutical agents. In QPI, a diffusion-based finite element model of light transport in scattering media, with δ-Eddington scattering coefficients, is fitted to the absorbed energy distribution to estimate the optical coefficient maps. The approach described here uses a recursive algorithm and converges quickly on the absorption coefficient distribution, when the scattering is known. By adding an area of known absorption, an unknown constant scattering coefficient may also be recovered. With optical coefficient maps estimated in this way, QPI has the potential to be a powerful tool for quantifying the concentration of molecular markers in photoacoustic molecular imaging.
影响因子：
2.8
作者：
Kruger, Robert A;Kiser, William L;Miller, Kathy D
通讯作者：
Miller, Kathy D