Institute for Biological and Medical Imaging, Technical University of Munich and Helmholtz Center Munich, Ingolstädter Landstrasse 1, 85764 Neuherberg, Germany.
Phys Med Biol. 2011 Sep 21;56(18):6129-48. doi: 10.1088/0031-9155/56/18/021. Epub 2011 Aug 26.
In this paper, it is demonstrated that the effects of acoustic attenuation may play a significant role in establishing the quality of tomographic optoacoustic reconstructions. Accordingly, spatially dependent reduction of signal amplitude leads to quantification errors in the reconstructed distribution of the optical absorption coefficient while signal broadening causes loss of image resolution. Here we propose a correction algorithm for accounting for attenuation effects, which is applicable in both the time and frequency domains. It is further investigated which part of the optoacoustic signal spectrum is practically affected by those effects in realistic imaging scenarios. The validity and benefits of the suggested modelling and correction approaches are experimentally validated in phantom measurements.
本文证明了声衰减的影响可能在建立层析光声重建的质量方面起着重要作用。因此,信号幅度的空间依赖性降低会导致重建的光吸收系数分布中的定量误差,而信号展宽则会导致图像分辨率的损失。在这里,我们提出了一种用于考虑衰减效应的校正算法,该算法可同时应用于时域和频域。进一步研究了在实际成像场景中,这些效应实际影响了光声信号频谱的哪个部分。在体模测量中,实验验证了所提出的建模和校正方法的有效性和益处。