title: Influence of probe pressure on the diffuse correlation spectroscopy blood flow signal: extra-cerebral contributions.
abstract: A pilot study explores relative contributions of extra-cerebral (scalp/skull) versus brain (cerebral) tissues to the blood flow index determined by diffuse correlation spectroscopy (DCS). Microvascular DCS flow measurements were made on the head during baseline and breath-holding/hyperventilation tasks, both with and without pressure. Baseline (resting) data enabled estimation of extra-cerebral flow signals and their pressure dependencies. A simple two-component model was used to derive baseline and activated cerebral blood flow (CBF) signals, and the DCS flow indices were also cross-correlated with concurrent Transcranial Doppler Ultrasound (TCD) blood velocity measurements. The study suggests new pressure-dependent experimental paradigms for elucidation of blood flow contributions from extra-cerebral and cerebral tissues.
authors.affiliation: Department of Physics & Astronomy, University of Pennsylvania, 3231 Walnut St., Philadelphia, PA 19104, USA ; Institute of Physics, University of Campinas, 777 Sergio Buarque de Holanda St., Campinas, SP 13083-859, Brazil.
authors.forename: Rickson C
authors.initials: RC
authors.lastname: Mesquita
authors.forename: Steven S
authors.initials: SS
authors.lastname: Schenkel
authors.forename: David L
authors.initials: DL
authors.lastname: Minkoff
authors.forename: Xiangping
authors.initials: X
authors.lastname: Lu
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Favilla
authors.forename: Patrick M
authors.initials: PM
authors.lastname: Vora
authors.forename: David R
authors.initials: DR
authors.lastname: Busch
authors.forename: Malavika
authors.initials: M
authors.lastname: Chandra
authors.forename: Joel H
authors.initials: JH
authors.lastname: Greenberg
authors.forename: John A
authors.initials: JA
authors.lastname: Detre
authors.forename: A G
authors.initials: AG
authors.lastname: Yodh
keywords: (170.2655) Functional monitoring and imaging; (170.3660) Light propagation in tissues; (170.3880) Medical and biological imaging; (170.6480) Spectroscopy, speckle