Firbank M, Okada E, Delpy D T
Department of Medical Physics and Bioengineering, University College London, UK.
Phys Med Biol. 1997 Mar;42(3):465-77. doi: 10.1088/0031-9155/42/3/002.
This paper derives an analytical model for investigating the effect of the distribution of absorbers upon light attenuation in a scattering medium. Results from this are found to agree with those of Monte Carlo simulations. The implications of this model are then examined for their likely effect upon the measurement of cerebral blood volume (CBV) using near-infrared (NIR) spectroscopy. We conclude that, given the small diameter of the majority of cerebral blood vessels, the distribution of the blood will have little effect upon the measurement of CBV. Where changes to the blood volume occur in the larger (> 0.2 mm diameter) vessels on the surface of the brain, NIR spectroscopy is likely to underestimate the change.
本文推导了一个分析模型，用于研究吸收体分布对散射介质中光衰减的影响。结果表明，该模型结果与蒙特卡罗模拟结果一致。然后，研究了该模型对使用近红外（NIR）光谱测量脑血容量（CBV）可能产生的影响。我们得出结论，鉴于大多数脑血管直径较小，血液分布对CBV测量的影响很小。当大脑表面较大（直径>0.2毫米）血管的血容量发生变化时，近红外光谱可能会低估这种变化。
