title: Hemodynamic response to visual stimulation in newborn infants using functional near-infrared spectroscopy.
abstract: Brain activity is associated with physiological changes, which alter the optical properties of tissue. These changes can be detected by near-infrared spectroscopy (NIRS). Aim of the study was to determine changes in cerebral oxygenation in response to stimulation in the visual cortex in newborn infants during spontaneous sleep in the first days of life. We used an in-house developed multichannel NIRS imaging instrument, the MCP-II, to measure changes in concentration of oxyhemoglobin (O(2)Hb) and deoxyhemoglobin (HHb) in specific brain areas. In 10 out of 15 subjects, a significant increase in O(2)Hb and/or a significant decrease in HHb were found in one or more channels over the occipital cortex. During stimulation, O(2)Hb increased by a mean of 0.98 mumol/l, HHb decreased by a mean 0.17 mumol/l, and total-Hb increased by a mean of 0.81 mumol/l. The hemodynamic response to visual stimulation in the occipital cortex in newborn infants is similar to adults. The increase in O(2)Hb and the simultaneous decrease in HHb during stimulation suggest an increase in cerebral blood flow (CBF) that overcompensates for the increased oxygen consumption (CMRO(2)) in the activated cortical area.
authors.affiliation: Clinic of Neonatology, University Hospital Zurich, Switzerland.
authors.forename: Tanja
authors.initials: T
authors.lastname: Karen
authors.forename: Geert
authors.initials: G
authors.lastname: Morren
authors.forename: Daniel
authors.initials: D
authors.lastname: Haensse
authors.forename: Andrea S
authors.initials: AS
authors.lastname: Bauschatz
authors.forename: Hans Ulrich
authors.initials: HU
authors.lastname: Bucher
authors.forename: Martin
authors.initials: M
authors.lastname: Wolf
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology; D000367:Age Factors; D000375:Aging / Q000502:physiology; D001931:Brain Mapping / Q000379:methods*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D006454:Hemoglobins / Q000032:analysis / Q000378:metabolism; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology; D010108:Oxyhemoglobins / Q000032:analysis / Q000378:metabolism; D010775:Photic Stimulation; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D014793:Visual Cortex / Q000098:blood supply / Q000254:growth & development / Q000378:metabolism*; D014796:Visual Perception / Q000502:physiology*
chemical_list: D006454:Hemoglobins; D010108:Oxyhemoglobins; C100003:deoxyhemoglobin