Near-infrared oximetry of the brain

@article{Madsen1999NearinfraredOO,
  title={Near-infrared oximetry of the brain},
  author={Per Lav Madsen and Niels H Secher},
  journal={Progress in Neurobiology},
  year={1999},
  volume={58},
  pages={541-560}
}
Near-Infrared Spectroscopy
TLDR
In the absence of independent direct measures of path length and cerebral chromophore concentration as well as the influence of skull thickness on photon migration, the putative “absolute” concentrations of oxy- and deoxyhemoglobin produced by some cerebral oximeters should be viewed as unvalidated estimates.
4 Near-Infrared Spectroscopy
TLDR
NIRS technology makes it possible to apply critical safety thresholds with regards to cerebral tissue saturation in order to avoid dangerously low levels with the primary goal being to reduce mortality rates and cognitive deficits due to cerebral hypoxemia.
Near infrared spectroscopy.
TLDR
NIRS technology makes it possible to apply critical safety thresholds with regards to cerebral tissue saturation in order to avoid dangerously low levels with the primary goal being to reduce mortality rates and cognitive deficits due to cerebral hypoxemia.
Near-infrared spectroscopy in evaluation of cerebral oxygenation during vasovagal syncope.
TLDR
Results of the examination have shown that the changes in cerebral oxygenation measured by the NIRS technique are distinctly visible before the syncope, and a gradual decrease of oxyhaemoglobin followed by its sudden drop was observed in all the VVS patients.
Noninvasive measurement of cerebral hemoglobin oxygen saturation using two near infrared spectroscopy approaches.
TLDR
Comparisons of forehead tissue oxygenation index (TOI) with the calculated SvO2 during venous occlusion in 16 adult volunteers using a clinical two-channel SRS oximeter confirmed that cerebral cortex hemoglobin oxygen saturation, measured directly by the SRS method, reflects predominantly the saturation of the intracranial venous compartment of circulation.
Noninvasive measurement of cerebral hemoglobin oxygen saturation using two near infrared spectroscopy approaches
TLDR
Comparisons of forehead tissue oxygenation index (TOI) with the calculated SvO 2 during venous occlusion in 16 adult volunteers using a clinical two-channel SRS oximeter showed that cerebral cortex hemoglobin oxygen saturation, measured directly by the SRS method, reflects predominantly the saturation of the intracranial venous compartment of circulation.
Usefulness of Cerebral Oximetry in TBI by NIRS
TLDR
This paper summarizes the usefulness of monitoring cerebral oximetry by near-infrared spectroscopy in patients with traumatic brain injury, taking into account the advantages and the disadvantages of this technique.
Interference of Cerebral Near-Infrared Oximetry in Patients with Icterus
TLDR
In 48 patients undergoing orthotopic liver transplantation, bilirubin dampens the spectrophotometry-determined cerebral oxygen saturation at 733 and 809 nm, suggesting that tissue pigmentation deposits also absorb light.
Tissue Oxygen Index: Thresholds for Cerebral Ischemia Using Near-Infrared Spectroscopy
TLDR
A drop in TOI is defined that can be adopted as a threshold for severe cerebral ischemia with high sensitivity and specificity and thus improve the clinical use of near infrared spectroscopy.
Principles, techniques, and limitations of near infrared spectroscopy.
TLDR
NIRS is a noninvasive and relatively low-cost optical technique that is becoming a widely used instrument for measuring tissue O2 saturation, changes in hemoglobin volume and, indirectly, brain/muscle blood flow and muscle O2 consumption.
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References

SHOWING 1-10 OF 168 REFERENCES
Cerebral Hemoglobin and Optical Pathlength Influence Near-Infrared Spectroscopy Measurement of Cerebral Oxygen Saturation
TLDR
Data indicate that intersubject variability in NIRS originates, in part, from biologic variations in transcranial optical pathlength and cerebral hemoglobin concentration, and Instruments to account for these factors may improve N IRS cerebral oxygen saturation measurements.
Extracerebral absorption of near infrared light influences the detection of increased cerebral oxygenation monitored by near infrared spectroscopy.
TLDR
This study shows that the Invos 3100 monitor is sensitive to tissue oxygenation but does not reliably detect changes in cerebral oxygenation as a result of profound cerebral hyperaemia.
The Influence of Carbon Dioxide and Body Position on Near-Infrared Spectroscopic Assessment of Cerebral Hemoglobin Oxygen Saturation
TLDR
This work examined the correlation between the spectroscopic signal generated by a prototype cerebral oximeter, and global brain hemoglobin oxygen saturation calculated from arterial and jugular venous bulb oxygen saturations, and found that changes in position did not influence the association between CSf O2 and CScomb O2.
The effect of scalp ischaemia on measurement of cerebral blood volume by near-infrared spectroscopy.
TLDR
It is concluded that, provided the distance between light entry and exit on the surface of the scalp is sufficiently large, changes in scalp blood flow have no effect on NIRS measurement of cerebral haemodynamics.
Validation of transcranial near-infrared spectroscopy for evaluation of cerebral blood flow autoregulation.
TLDR
It is concluded that the cerebral oximeter might be useful in evaluation of the lower limit of cerebral autoregulation, but this method is of no value for estimation of levels of global cerebral oxygen saturation.
Resolving extra- and intracranial signal changes during adult near infrared spectroscopy.
TLDR
NIRS can provide quantified thresholds for severe ischemia in the adult brain provided the extracranial component is removed and was applied to 703 consecutive patients undergoing carotid surgery for high grade stenosis.
Noninvasive, infrared monitoring of cerebral and myocardial oxygen sufficiency and circulatory parameters.
TLDR
Observations by infrared transillumination in the exposed heart and in the brain in cephalo without surgical intervention show that oxygen sufficiency for cytochrome a,a3, function, changes in tissue blood volume, and the average hemoglobin-oxyhemoglobin equilibrium can be recorded effectively and in continuous fashion for research and clinical purposes.
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