Abstract
Activation of the cerebral cortex induces a localized change in the volume and oxygenation of the blood. Because the change in spectral reflectance of the cortex depends upon the concentration changes in oxy- and deoxy haemoglobin, multi-spectral imaging has been applied to investigate the functional activity of the exposed cortex related to oxy- and deoxy haemoglobin. However, brain tissue is a highly scattering medium, and the reflectance of cortical tissue depends on the mean optical path length of the detected light. The linear spectrographic analysis method without wavelength-dependent path length scaling may produce unreliable results in multi-spectral image analysis. In this study, we propose a method of estimating the wavelength-dependent path length factor from the principal component analysis of the multi-spectral images of the exposed cortex. The optical path-length factor estimated from the first principal component of the multi-spectral image of the cortical model and the absorption spectrum of haemoglobin agrees with that predicted by Monte Carlo simulation. The tendency of the optical path-length factor of the pig brain estimated from the first principal component of the multi-spectral images is almost the same as that of the cortical model.
Original language | English |
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Pages (from-to) | 168-179 |
Number of pages | 12 |
Journal | Proceedings of SPIE - The International Society for Optical Engineering |
Volume | 5138 |
DOIs | |
Publication status | Published - 2003 |
Event | Photon Migration and Diffuse-Light Imaging - Munich, Germany Duration: 2003 Jun 22 → 2003 Jun 23 |
Keywords
- Exposed cortex
- Monte Carlo simulation
- Optical path-length factor
- Principal component analysis
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Computer Science Applications
- Applied Mathematics
- Electrical and Electronic Engineering