University College London, Department of Medical Physics and Bioengineering, Malet Place Engineering Building, London, WC1E 6BT, United Kingdom.
J Biomed Opt. 2010 Sep-Oct;15(5):055007. doi: 10.1117/1.3495729.
Ultrasound-modulated optical tomography (UOT) is based on "tagging" light in turbid media with focused ultrasound. In comparison to diffuse optical imaging, UOT can potentially offer a better spatial resolution. The existing Monte Carlo (MC) model for simulating ultrasound-modulated light is central processing unit (CPU) based and has been employed in several UOT related studies. We reimplemented the MC model with a graphics processing unit [(GPU), Nvidia GeForce 9800] that can execute the algorithm up to 125 times faster than its CPU (Intel Core Quad) counterpart for a particular set of optical and acoustic parameters. We also show that the incorporation of ultrasound propagation in photon migration modeling increases the computational time considerably, by a factor of at least 6, in one case, even with a GPU. With slight adjustment to the code, MC simulations were also performed to demonstrate the effect of ultrasonic modulation on the speckle pattern generated by the light model (available as animation). This was computed in 4 s with our GPU implementation as compared to 290 s using the CPU.
超声调制光学断层成像（UOT）基于用聚焦超声对混浊介质中的光进行“标记”。与漫射光学成像相比，UOT 有可能提供更好的空间分辨率。现有的用于模拟超声调制光的蒙特卡罗（MC）模型是基于中央处理器（CPU）的，并已在几项 UOT 相关研究中得到应用。我们使用图形处理单元（GPU，Nvidia GeForce 9800）重新实现了 MC 模型，该模型对于特定的光学和声学参数集，其执行算法的速度比其 CPU（Intel Core Quad）版本快 125 倍。我们还表明，在光子迁移建模中加入超声传播会大大增加计算时间，在一种情况下，即使使用 GPU，也会增加至少 6 倍。通过对代码进行轻微调整，还进行了 MC 模拟，以演示超声调制对由光模型生成的散斑图案的影响（提供动画）。使用我们的 GPU 实现，这在 4 秒内完成，而使用 CPU 则需要 290 秒。
