title: Assessment of a multi-layered diffuse correlation spectroscopy method for monitoring cerebral blood flow in adults.
abstract: Diffuse correlation spectroscopy (DCS) is a promising technique for brain monitoring as it can provide a continuous signal that is directly related to cerebral blood flow (CBF); however, signal contamination from extracerebral tissue can cause flow underestimations. The goal of this study was to investigate whether a multi-layered (ML) model that accounts for light propagation through the different tissue layers could successfully separate scalp and brain flow when applied to DCS data acquired at multiple source-detector distances. The method was first validated with phantom experiments. Next, experiments were conducted in a pig model of the adult head with a mean extracerebral tissue thickness of 9.8 ± 0.4 mm. Reductions in CBF were measured by ML DCS and computed tomography perfusion for validation; excellent agreement was observed by a mean difference of 1.2 ± 4.6% (CI95%: -31.1 and 28.6) between the two modalities, which was not significantly different.
authors.affiliation: Imaging Program, Lawson Health Research Institute, London, Ontario N6A 4V2, Canada; Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 3K7, Canada.
authors.forename: Kyle
authors.initials: K
authors.lastname: Verdecchia
authors.affiliation: Imaging Program, Lawson Health Research Institute, London, Ontario N6A 4V2, Canada; Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 3K7, Canada.
authors.forename: Mamadou
authors.initials: M
authors.lastname: Diop
authors.affiliation: Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 3K7, Canada.
authors.forename: Albert
authors.initials: A
authors.lastname: Lee
authors.affiliation: Imaging Program, Lawson Health Research Institute, London, Ontario N6A 4V2, Canada; Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 3K7, Canada.
authors.forename: Laura B
authors.initials: LB
authors.lastname: Morrison
authors.affiliation: Imaging Program, Lawson Health Research Institute, London, Ontario N6A 4V2, Canada; Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 3K7, Canada; Imaging Research Laboratories, Robarts Research Institute, London, Ontario N6G 2V4, Canada.
authors.forename: Ting-Yim
authors.initials: TY
authors.lastname: Lee
authors.affiliation: Imaging Program, Lawson Health Research Institute, London, Ontario N6A 4V2, Canada; Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 3K7, Canada.
authors.forename: Keith
authors.initials: K
authors.lastname: St Lawrence
keywords: (170.1470) Blood or tissue constituent monitoring; (170.3660) Light propagation in tissues; (170.3880) Medical and biological imaging; (170.6935) Tissue characterization