【摘要】 报道了基于 32通道时间分辨光学层析成像系统的的差分图像重建结果。实验采用两个光学参数与生物组织体大致相同的圆柱型模拟体 ,分别用于模拟新生儿头部和成人手臂。重建结果表明 :采用差分测量的方法很好地重建出了异质体的位置、尺寸及吸收系数相对于背景的变化 ;模拟和实验重建验证了所发展的二维 ,半三维重建算法的可行性 ;使用平均飞行时间作为数据类型、32个探测通道测量 ,比用强度作为数据类型或 16通道测量更为准确地区分出了两个相距 2 0mm的异质体。结果表明用目前的系统可以定性地重建出异质体的位置、尺寸、吸收系数的变化 ,展示该光学层析成像技术将在监测诸如血液含氧量变化、组织体涉氧新陈代谢等生理过程中具有良好应用前景。也对该种成像方法所存在的问题及进一步改进的措施进行了讨论。更多还原

【Abstract】 Optical image reconstruction of absorption distribution by use of differential time resolved measurements from a 32 channel optical tomography system is reported for two cylindrical phantoms which have optical properties in the range of these expected for living tissue. Images with different heterogeneity locations, sizes, and absorption coefficients have been achieved with good qualities. Simulated and experimental reconstructions show that the 2 D, semi 3 D algorithms are effective. Two heterogeneitis which are 20 mm apart are distinguished more clearly by using mean time as the data type from 32 channel measurement than that by using intensity as data type or from 16 channel measurement. Results suggest that qualitative images can be achieved in terms of heterogeneities locations, sizes, and the change of absorption from this system. Some of the existing problems associated with the multi channel time resolved system are discussed.更多还原