用于定位激发平面的混合高斯方法

Location Method of Excitation Planes Based on Gaussian Mixture Distribution

荧光分子断层成像是一种高稳定性、低副作用的分子影像技术,一直是生物光学领域的研究热点,当激发平面位置与荧光目标位置接近时,光源的重建结果会更好;为了确定激发平面的位置,提出了一种混合高斯方法,该方法首先使用少量激发光源来获得发射光的生物体外表面分布,再使用带剪枝策略的混合高斯模型对该分布进行拟合,最后利用拟合后的峰值自动确定激发平面的个数和位置;基于新激发平面的激发光源可以获得荧光分子断层成像逆问题,进而利用该逆问题对荧光目标进行重建。实验结果表明:基于重新定位的激发平面的荧光分子断层成像光源重建结果在定位精度上显著优于原始激发平面对应的重建结果。

Fluorescence molecular tomography is a robust molecular imaging technology with low side effects which is a very hot topic in photobiology always. The fluorescence molecular tomography has better reconstruction results generally, if the excitation plane is close to the fluorescent targets. To find better excitation planes, we propose a location method of excitation planes based on mixture Gaussian distribution. Firstly, the method uses several excitation sources to obtain the living organism external surface distribution of the emitting light. Secondly, the Gaussian mixture model with pruning strategy is used to fit the distribution. Finally, the number and locations of the excitation planes are automatically determined according to fitted peak values. Fluorescence molecular tomography inverse problems are built based on the excitation light source of new excitation planes, and fluorescent targets are reconstructed using the inverse problems. Experimental results demonstrate that the fluorescence molecular tomograpby reconstruction results depending on the new excitation planes are much better than the results depending on original excitation planes.