Quantitative evaluation of frequency domain measurements in high density diffuse optical tomography

Abstract

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Dual-Slope Imaging in Frequency-Domain Near-Infrared Spectroscopy

“…This may be somewhat surprising, as one may think that ρ max is the important parameter (this was the naïve and incorrect assumption in Reference 21). Additionally, many methods and arrays in functional Near-InfraRed Spectroscopy (fNIRS) use a very short ρ (i.e., 5 mm to 10 mm) for superficial hemodynamics subtraction [7][8][9][10]12 or multiple ρs including a short one, 4,16,17 which from the perspective of these simulations would hurt S depth since ρ would be decreased. However, these methods do not utilize DS and instead typically attempt to also reconstruct superficial hemodynamics and then remove them, which is not the method used here.…”

“…[7][8][9][10] Recently, there has been a push to implement imaging arrays using FD or TD NIRS to gain φ or higher moments information in an attempt to retrieve optical data that are intrinsically sensitive to deeper tissue. 11,12,[15][16][17] Furthermore, typical implementations of DOI utilize Single-Distance (SD) based source-detector arrangements that consist of source-detector pairs spaced at various distances source-detector distances (ρs) across the SD sets. 4,18 SD measurements are known to be largely sensitive to superficial tissue.…”