Biomedical Engineering Reference
In-Depth Information
For
in vivo
evaluation, the estimated parameters for the skin model corresponded to
apriori
expectations. We have shown that increasing the wavelength of incoming light
(in the range of 635-830 nm) increases the mean depth probed. Moreover, an increase
of the source-detection fibre separations leads to a higher mean depth and M1 value.
When different wavelengths were compared it was not obtained a clear tendency.
Regarding the rat brain model, the mean depth that photons Doppler shifted travel
was estimated to be 0.15 mm which is in agreement with the literature. In the measure-
ments, the blood flow changes were detected with the micro-probe built which means
that the probe localization (0.15 mm above the measurement area) is correct.
Acknowledgements.
The authors thank the Instituto de Investigação Interdisciplinar
(III) of the University of Coimbra, Acções Integradas Luso-Francesas (PAUILF) and
Fundação para a Ciência e a Tecnologia (FCT), Lisbon, for supporting this work.
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