The effect of temporal impulse response on experimental reduction of photon scatter in time-resolved diffuse optical tomography.
The effect of temporal impulse response on experimental reduction of photon scatter in time-resolved diffuse optical tomography.
复制标题
DOI：
10.1088/0031-9155/58/2/335
复制
发表时间：
2013-01-21
影响因子：
3.5
通讯作者：
Niedre M
中科院分区：
文献类型：
--
作者：
Valim N;Brock J;Leeser M;Niedre M
近年来，新的快速探测器技术已经推动了对早期光子的时间分辨测量的重大重新关注，以提高漫射光学层析成像和荧光介导层析成像的成像分辨率。在实践中，早期光子的选择导致仪器光子密度灵敏度函数（PDSF）比连续波情况明显更窄，从而导致更好的条件重建问题。在这项工作中，我们研究了仪器的时间脉冲响应函数（TIRF）的定量影响的组织模仿光学幻影的实验PDSF。我们使用了多模光纤色散的方法来改变系统TIRF在一个范围内的代表性文献值。PDSF宽度的实质性分歧-高达40% -观察到的实验测量和蒙特卡罗（MC）模型的光子传播的范围内的TIRFs研究。平均而言，在早期，在2 cm宽的成像室的中心平面处，每100 ps仪器TIRF的PDSF加宽约0.3 mm。此外，这种加宽在源侧和检测器侧都是相当的。通过仪器TIRF与MC模拟的卷积证实了结果。这些数据还强调了在执行断层图像重建时校正仪器TIRF的成像PDSF的重要性，以确保准确的数据模型一致性。
New fast detector technology has driven significant renewed interest in time-resolved measurement of early photons in improving imaging resolution in diffuse optical tomography and fluorescence mediated tomography in recent years. In practice, selection of early photons results in significantly narrower instrument photon density sensitivity functions (PDSFs) than the continuous wave case, resulting in a better conditioned reconstruction problem. In this work, we studied the quantitative impact of instrument temporal impulse response function (TIRF) on experimental PDSFs in tissue mimicking optical phantoms. We used a multi-mode fiber dispersion method to vary the system TIRF over a range of representative literature values. Substantial disagreement in PDSF width – by up to 40% - was observed between experimental measurements and Monte Carlo (MC) models of photon propagation over the range of TIRFs studied. On average, PDSFs were broadened by about 0.3 mm at the center plane of the 2 cm wide imaging chamber per 100 ps of instrument TIRF at early times. Further, this broadening was comparable on both the source and detector sides. Results were confirmed by convolution of instrument TIRFs with MC simulations. These data also underscore the importance of correcting imaging PDSFs for instrument TIRF when performing tomographic image reconstruction to ensure accurate data-model agreement.