University of Wisconsin-Milwaukee, Electrical and Computer Engineering Department, 3200 North Cramer Street, Milwaukee, Wisconsin 53211, United States.
University of Wisconsin-Milwaukee, Psychology Department, 2441 East Hartford Avenue, 207 Garland Hall, Milwaukee, Wisconsin 53211, United States.
J Biomed Opt. 2017 Jan 1;22(1):16003. doi: 10.1117/1.JBO.22.1.016003.
We present our effort in implementing a fluorescence laminar optical tomography scanner which is specifically designed for noninvasive three-dimensional imaging of fluorescence proteins in the brains of small rodents. A laser beam, after passing through a cylindrical lens, scans the brain tissue from the surface while the emission signal is captured by the epi-fluorescence optics and is recorded using an electron multiplication CCD sensor. Image reconstruction algorithms are developed based on Monte Carlo simulation to model light–tissue interaction and generate the sensitivity matrices. To solve the inverse problem, we used the iterative simultaneous algebraic reconstruction technique. The performance of the developed system was evaluated by imaging microfabricated silicon microchannels embedded inside a substrate with optical properties close to the brain as a tissue phantom and ultimately by scanning brain tissue in vivo. Details of the hardware design and reconstruction algorithms are discussed and several experimental results are presented. The developed system can specifically facilitate neuroscience experiments where fluorescence imaging and molecular genetic methods are used to study the dynamics of the brain circuitries.
我们介绍了我们在实现荧光层光学层析扫描仪方面的努力，该扫描仪专门用于对小啮齿动物大脑中的荧光蛋白进行非侵入性的三维成像。激光束经过柱面透镜后，从表面扫描脑组织，而发射信号则通过背向荧光光学器件捕获，并使用电子倍增 CCD 传感器记录。基于蒙特卡罗模拟开发了图像重建算法，以模拟光-组织相互作用并生成灵敏度矩阵。为了解决逆问题，我们使用了迭代同时代数重建技术。通过对具有与脑组织相近光学特性的基底内嵌入的微加工硅微通道进行成像，作为组织体模，最终对活体脑组织进行扫描，评估了所开发系统的性能。讨论了硬件设计和重建算法的细节，并给出了一些实验结果。所开发的系统特别有助于神经科学实验，其中荧光成像和分子遗传方法用于研究大脑回路的动力学。
