利用光源附近微区漫反射测量组织微观结构参数γ的方法

Method to Quantitate Parameter γ Related to Tissue Microstructure by Reflectance Measured at Microdomains Close to the Source

提出一种利用光纤探头测量组织微观结构参数γ的方法.根据Intralipid组织模拟液球状分形结构,采用蒙特卡罗模拟方法得到光子经Intralipid漫反射的数据样本,通过对数据进行非线性拟合,建立漫反射率与γ的函数关系.研究发现漫反射率与无量纲的约化散射系数μ_s′ф(ф是散射光的收集孔径)呈线性关系,其斜率是γ的二次函数.实验中以Intralipid为样本得到了不同μ_s′ф下的漫反射率,验证了漫反射率与μ_s′ф的线性关系,并利用其斜率获得了Intralipid的γ值为2.04,分形维数为2.93,各向异性因子为0.816,与文献报道相符,验证了该方法的可行性.

A method of measuring tissue microstructure parameterγwith optical fiber probe was presented.Based on spherical fractal model of Intralipid,the diffuse reflection data of the photon through Intralipid was obtained using Monte Carlo simulation,and the function relationship between diffuse reflectance andγwas established by non-linear fitting of the data.Research shows that the diffuse reflectance is linearly related to the dimensionless reduced scattering coefficientμs′φ(φis selecting aperture)and its slope is a quadratic function ofγ.In the experiment,the diffuse reflectance of differentμs′φwas obtained with Intralipid,the linear relationship between diffuse reflectance andγwas verified.Theγof 2.04,the fractal dimension of 2.93 and the anisotropy factor of 0.816 were obtained by the slope,which were in good agreement with the parameters in literature,verifying the feasibility of the proposed method.