Assessment of a multi-layered diffuse correlation spectroscopy method for monitoring cerebral blood flow in adults

Kyle Verdecchia; Mamadou Diop; Albert Lee; Laura B Morrison; Ting-Yim Lee; Keith St Lawrence

doi:10.1364/BOE.7.003659

Assessment of a multi-layered diffuse correlation spectroscopy method for monitoring cerebral blood flow in adults

Biomed Opt Express. 2016 Aug 24;7(9):3659-3674. doi: 10.1364/BOE.7.003659. eCollection 2016 Sep 1.

Authors

Kyle Verdecchia¹, Mamadou Diop¹, Albert Lee², Laura B Morrison¹, Ting-Yim Lee³, Keith St Lawrence¹

Affiliations

¹ Imaging Program, Lawson Health Research Institute, London, Ontario N6A 4V2, Canada; Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 3K7, Canada.
² Department of Medical Biophysics, University of Western Ontario, London, Ontario N6A 3K7, Canada.
³ 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.

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% (CI_95%: -31.1 and 28.6) between the two modalities, which was not significantly different.

Keywords: (170.1470) Blood or tissue constituent monitoring; (170.3660) Light propagation in tissues; (170.3880) Medical and biological imaging; (170.6935) Tissue characterization.