Abstract
We performed reflectance measurements with a time-resolved white-light spectroscopy system to monitor concentrations changes in a two-layer liquid phantom with optical properties similar to human tissues. By varying the concentrations of three inks with different spectral features, we changed the absorption coefficient of the upper and lower layer to simulate either haemodynamics changes in the muscle covered by adipose layer, or functional brain activation with systemic response in the scalp. Data were analyzed by a time-resolved spectrally constrained fitting method based on a homogeneous model of photon diffusion. Although this approach is based on a homogeneous model and employs a single 2cm source-detector distance, the technique is able to monitor changes in the lower layer, while it is scarcely affected by variation in the upper layer. Preliminary in vivo measurements have been performed on one healthy volunteer to monitor oxy- and deoxy-haemoglobin changes in the muscle during arterial occlusion and in the brain during a motor task. Even if the overall sensitivity of the technique is reduced, in vivo results are in general agreement with the findings of dedicated system for tissue oximetry.
© 2007 SPIE
PDF ArticleMore Like This
Rinaldo Cubeddu, Cosimo D’Andrea, Antonio Pifferi, Paola Taroni, Alessandro Torricelli, and Gianluca Valentini
MG1 Biomedical Optical Spectroscopy and Diagnostics (BIOMED) 2000
C. D’Andrea, A. Bassi, J. Swartling, A. Pifferi, A. Torricelli, and R. Cubeddu
ThA1 European Conference on Biomedical Optics (ECBO) 2005
Alessandro Torricelli, Davide Contini, Lorenzo Spinelli, Rinaldo Cubeddu, Franco Molteni, Simona Ferrante, Alessandra Pedrocchi, and Giancarlo Ferrigno
6629_57 European Conference on Biomedical Optics (ECBO) 2007