超声调制光信号的调制深度与组织光学特性关系

超声调制光学成像技术融合了光学成像和超声成像的优点,已实现对浑浊介质内隐藏异体的成像,是一种很有前景的医学成像技术。通过实验探究超声调制光信号与组织光学特性的关系、超声焦区内外组织的光学特性对调制信号的影响,发现超声对光信号的调制深度与超声焦区组织的光学性质呈简单的线性关系,调制深度随样品散射系数的增大而减小,随样品吸收系数的增大而增大。超声区信号调制深度基本不受超声调制区域外复杂组织的光学特性的影响。这为超声调制光学成像提供必要的图像重构依据。

Relation Between Modulation Depth of Ultrasound-Modulated Optical Signal and Tissue Optical Properties

Ultrasound modulated optical tomography combines the advantages of light imaging with ultrasound and is able to image objects embedded in turbid medium.It is a promising technique.A relation between the modulated optical signal and the optical parameters of tissue inside and outside of the ultrasound zone is given by experiment.It is discovered that the modulation depth is directly relevant to the optical properties of the tissue at the ultrasound focal zone.The modulation depth reduces as the scattering coefficient of sample increases,and increases with the increase of absorption coefficient.The modulation depth of signal in ultrasound zone is not subject to the optical properties of complex tissue outside of the ultrasound zone.All these results will provide necessary basis for the image reconstruction of ultrasound modulated optical tomography.