Politecnico di Milano, Dipartimento di Fisica e Instituto di Fotonica e Nanotecnologie, Piazza Leonardo da Vinci 32, I-20133 Milan, Italy.
Phys Med Biol. 2012 Jun 21;57(12):3811-32. doi: 10.1088/0031-9155/57/12/3811. Epub 2012 May 29.
In order to reduce both acquisition and reconstruction times, illumination and detection in fluorescence diffuse optical tomography (FDOT) have recently evolved from a point-based to a pattern-based approach. The use of structured illumination, offering the ability to project any pattern of light onto the object, associated with the compression of the acquired fluorescence images has paved the way for a new generation of fast reconstruction algorithms for FDOT. However, the choice of the most appropriate set of source patterns is still an open problem. Here, the use of typical source patterns is investigated on experimental data. Reconstructions of similar qualities are obtained for the different types of source patterns. We found that the performances of structured illumination are limited by the required positivity of the source patterns. To alleviate this problem, we introduce a novel method, namely the virtual source pattern method, which allows for considering any kind of patterns, e.g., with negative and complex intensities. This new method provides a significant increase of the contrast of the reconstruction and also a reduction of the reconstruction error, especially when virtual wavelet source patterns are considered.
为了减少采集和重建时间，荧光漫射光学断层成像术（FDOT）中的照明和检测最近已经从基于点的方法发展为基于模式的方法。使用结构照明，能够将任何模式的光投射到物体上，并与采集的荧光图像的压缩相结合，为 FDOT 的新一代快速重建算法铺平了道路。然而，选择最合适的源模式集仍然是一个未解决的问题。在这里，我们研究了实验数据中典型源模式的使用。对于不同类型的源模式，都可以获得相似质量的重建结果。我们发现，结构照明的性能受到源模式必须为正的限制。为了缓解这个问题，我们引入了一种新的方法，即虚拟源模式方法，它允许考虑任何类型的模式，例如具有负和复数强度的模式。这种新方法显著提高了重建的对比度，并降低了重建误差，尤其是当考虑虚拟小波源模式时。
