The event database contains all event-related information for the World of Photonics Congress.
Lecture Hall ICM - Internationales Congress Center München European Conferences on Biomedical Optics (ECBO) > Diffuse Optical Spectroscopy and Imaging > Theory, Algorithms and Computational Tools I
11:30-11:45 h | ICM - Internationales Congress Center München ICM Room 5
Subjects: Biophotonics and Medical Engineering
Chairman: Hamid Dehghani (, The Univ. of Birmingham)
Diffuse correlation spectroscopy (DCS) measures temporal intensity fluctuations of the optical field to noninvasively quantify the sample dynamics. DCS has many promising applications in neuroimaging as it can provide topography of the cortical activation due to neurovascular coupling. However, DCS lacks the photon path-length resolution. So, an information about the sample dynamics is integrated over all photon paths. Consequently, the useful, cortical signal is confounded by photons that traversed skull and scalp. Traditionally, this issue is compensated for by measurement geometries with large source-detector separations, ρ cm. This, however, significantly decrease the sensitivity because the number of detected photons decreases exponentially. To tackle this problem we extend DCS by time-gating, implemented with pulsed laser and time-correlated single photon counting. Then, we use this path-length-resolved or time-domain (TD-) DCS to quantify dynamics in a two-layer turbid phantom, comprising static and dynamic layers. We demonstrate that standard TD DCS processing is incapable to properly quantify dynamics in such a phantom at short ρ (