TY  - JOUR
Y1  - 2014/01/15/
A1  - Kolyva, C
A1  - Ghosh, A
A1  - Tachtsidis, I
A1  - Highton, D
A1  - Cooper, CE
A1  - Smith, M
A1  - Elwell, CE
IS  - 1
KW  - Cytochrome c oxidase;
    Hypoxia;
    Hyperoxia;
    Hypocapnia;
    Hypercapnia;
    Near-infrared spectroscopy;
TI  - Cytochrome c oxidase response to changes in cerebral oxygen delivery in the adult brain shows higher brain-specificity than haemoglobin
UR  - http://dx.doi.org/10.1016/j.neuroimage.2013.05.070
SP  - 234
VL  - 85
N2  - The redox state of cerebral mitochondrial cytochrome c oxidase monitored with near-infrared spectroscopy (?[oxCCO]) is a signal with strong potential as a non-invasive, bedside biomarker of cerebral metabolic status. We hypothesised that the higher mitochondrial density of brain compared to skin and skull would lead to evidence of brain-specificity of the ?[oxCCO] signal when measured with a multi-distance near-infrared spectroscopy (NIRS) system. Measurements of ?[oxCCO] as well as of concentration changes in oxygenated (?[HbO2]) and deoxygenated haemoglobin (?[HHb]) were taken at multiple source-detector distances during systemic hypoxia and hypocapnia (decrease in cerebral oxygen delivery), and hyperoxia and hypercapnia (increase in cerebral oxygen delivery) from 15 adult healthy volunteers. Increasing source-detector spacing is associated with increasing light penetration depth and thus higher sensitivity to cerebral changes. An increase in ?[oxCCO] was observed during the challenges that increased cerebral oxygen delivery and the opposite was observed when cerebral oxygen delivery decreased. A consistent pattern of statistically significant increasing amplitude of the ?[oxCCO] response with increasing light penetration depth was observed in all four challenges, a behaviour that was distinctly different from that of the haemoglobin chromophores, which did not show this statistically significant depth gradient. This depth-dependence of the ?[oxCCO] signal corroborates the notion of higher concentrations of CCO being present in cerebral tissue compared to extracranial components and highlights the value of NIRS-derived ?[oxCCO] as a brain-specific signal of cerebral metabolism, superior in this aspect to haemoglobin.
AV  - public
EP  - 244
JF  - Neuroimage
N1  - © 2013 The Authors. Published by Elsevier Inc. All rights reserved. This is an open-access article distributed under the terms of the Creative Commons
Attribution License, which permits unrestricted use, distribution, and reproduction
in any medium, provided the original author and source are credited.
SN  - 1053-8119
ID  - discovery1395037
ER  -