THz imaging of Alzheimer's disease: Spectroscopic differentiation between normal and diseased tissues

We investigate the THz response of human brain tissue exhibiting Alzheimer's disease. Amyloid plaque buildup, believed to be a possible cause of this disease, is typically diagnosed by immunohistochemical inspection of beta-amyloid in ex vivo biopsy specimens. Using a broadband THz time domain spectrometer system in reflection mode imaging, we demonstrate the possibility of discriminating between major brain tissue components, including white and grey matter as based on their morphological and compositional differences. More importantly, the THz response of beta-amyloid plaque buildup within grey matter is significantly more pronounced and exhibits detectable differences from the otherwise healthy regions. These results offer the possibility of diagnosing Alzheimer's disease using THz imaging, ex vivo as in this study and potentially in vivo as THz imaging technologies continue to improve.