Comparing concurrent measurements of human cerebral blood flow changes using speckle contrast optical spectroscopy and diffuse correlation spectroscopy (Conference Presentation)

Speckle contrast optical spectroscopy (SCOS) is a camera-based diffuse optical technique that is increasingly being applied to measure human cerebral blood flow (CBF) noninvasively. Due to massively parallel speckle detection on the camera, SCOS is expected to offer higher contrast-to-noise ratio (CNR) in human CBF measurements than the current state-of-the-art technique of diffuse correlation spectroscopy (DCS). There is a lack of comparison studies between DCS and SCOS at larger (i.e. >2 cm) source-detector separations (SDS) where brain sensitivity is higher and biases from camera noise become greater in SCOS due to reduced photon flux. We performed concurrent SCOS and DCS measurements at 3 cm SDS during induced changes in human CBF to validate SCOS against DCS and evaluate the impact of SCOS’s CNR advantage.