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Updated: May 22, 2026

MRI Mapping of Cerebrovascular Reactivity via Gas Inhalation Challenges
Published on: December 17, 2014
Correlation between the arterial pulse wave of the cerebral microcirculation and CBF during breath holding and
1Department of Neurology, S. Pio Hospital, via C. De Lellis, 66054 Vasto (CH), Italy. stefano.viola@email.it
Objective:
To evaluate if relative changes in the amplitude of the arterial pulse wave of the cerebral microcirculation (APWCM) measured by near-infrared spectroscopy (NIRS) may provide information about relative changes of cerebral blood flow (CBF) in cerebral cortex.
Methods:
In 10 healthy human volunteers, through simultaneous recording of the APWCM amplitude by means of NIRS and the mean blood flow velocity (MBFV) of middle cerebral artery by means of transcranial Doppler (TCD) at rest and during breath holding and hyperventilation, we evaluate a possible correlation between relative changes of the mean APWCM amplitude and relative changes of MBFV.
Results:
We found a significant linear correlation: breath holding: R(2) 0.84, p < 0.001, hyperventilation: R(2) 0.81, p<0.001.
Conclusion:
The relative changes of the mean APWCM amplitude seem able to provide information about relative changes of CBF of cerebral cortex in healthy adult humans during breath holding and hyperventilation.
Significance:
APWCM detected by NIRS, a safe, repeatable, inexpensive technology and at the bedside may improve the study of cerebral cortex microcirculation in neurological diseases.
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