Study of local cerebral hemodynamics by frequency-domain near-infrared spectroscopy and correlation with simultaneously acquired functional magnetic resonance imaging

Toronov, Vladislav; Webb, Andrew; Choi, Jee Hyun; Wolf, Martin; Safonova, Larisa P.; Wolf, Ursula; Gratton, Enrico

doi:10.1364/oe.9.000417

Cited by 70 publications

(51 citation statements)

References 19 publications

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“…This allows comparisons of the spatial and temporal characteristics of the fMRI signals with optically-derived hemodynamic changes to clarify the contributions of different physiological parameters to the fMRI signals. Several studies of functional activations have been performed in the human motor cortex by simultaneous fMRI and NIRS (Toronov et al, , 2001b(Toronov et al, , 2003a. In particular it was found that, in the human motor cortex, the temporal dependence of the deoxyhemoglobin concentration was the factor most closely related to the BOLD fMRI signal.…”

Section: Introductionmentioning

confidence: 99%

A spatial and temporal comparison of hemodynamic signals measured using optical and functional magnetic resonance imaging during activation in the human primary visual cortex

2007

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Functional near infrared spectro-imaging (fNIRSI) is potentially a very useful technique for obtaining information about the underlying physiology of the blood oxygenation level dependent (BOLD) signal used in functional magnetic resonance imaging (fMRI). In this paper the temporal and spatial statistical characteristics of fNIRSI data are compared to those of simultaneously acquired fMRI data in the human visual cortex during a variable-frequency reversing checkerboard activation paradigm. Changes in the size of activated volume caused by changes in checkerboard reversal frequency allowed a comparison of the behavior of the spatial responses measured by the two imaging methods. fNIRSI and fMRI data were each analyzed using standard correlation and fixed-effect group analyses of variance pathways. The statistical significance of fNIRSI data was found to be much lower than that of the fMRI data, due mainly to the low signal-to-noise of the measurements. Reconstructed images also showed that, while the time-course of changes in the oxy-, deoxy-, and total hemoglobin concentrations all exhibit high correlation with that of the BOLD response, the changes in the volume of tissue measured as "activated" by the BOLD response demonstrate a closer similarity to the corresponding changes in the oxy-and total hemoglobin concentrations than to that of the deoxyhemoglobin.

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Section: Introductionmentioning

confidence: 99%

A spatial and temporal comparison of hemodynamic signals measured using optical and functional magnetic resonance imaging during activation in the human primary visual cortex

2007

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“…(Franceschini et al, 2000;Kennan et al, 2002;Colier et al, 2001;Obrig et al, 2002;Sato et al, 1999;Hoshi et al, 2000) The compatibility of optical imaging with other neuroimaging methods has received wide interest. Optical measurements have been successfully combined with fMRI (Kleinschmidt et al, 1996;Toronov et al, 2001), MEG (Mackert et al, 2002), EEG (Kennan et al, 2002;Israel et al, 2002) and TMS (Oliviero et al, 1999;Iwata et al, 2000;Nissilä et al, 2002b). Figure 13.…”

Section: 31d Practical Applicationsmentioning

confidence: 99%

Diffuse Optical Imaging

Nissilä

Noponen

Heino

et al.

Advances in Electromagnetic Fields in Living Systems

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Diffuse optical imaging is a functional medical imaging modality which takes advantage of the relatively low attenuation of near-infrared light to probe the internal optical properties of tissue. The optical properties are affected by parameters related to physiology such as the concentrations of oxy-and deoxyhemoglobin. Instrumentation that is used for optical imaging is generally able to measure changes in the attenuation of light at several wavelengths, and in the case of time-and frequency-domain instrumentation, the time-of-flight of the photons in tissue.Light propagation in tissue is generally dominated by scattering. Models for photon transport in tissue are generally based on either stochastic approaches or approximations derived from the radiative transfer equation. If a numerical forward model which describes the physical situation with sufficient accuracy exists, inversion methods may be used to determine the internal optical properties based on boundary measurements.Optical imaging has applications in, e.g., functional brain imaging, breast cancer detection, and muscle imaging. It has the important advantages of transportable instrumentation, relatively high tolerance for external electromagnetic interference, non-invasiveness, and applicability for neonatal studies. The methods are not yet in clinical use, and further research is needed to improve the reliability of the experimental techniques, and the accuracy of the models used. In this chapter, we describe the interaction between light and tissue, light propagation models and inversion methods used in optical tomography, and instrumentation and experimental techniques used in optical imaging. The main applications of optical imaging are described in detail, with results from recent literature.

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“…Calculations of Hb and HbO 2 concentration changes have been performed by the well established ''modified Beer-Lambert law'' [12,27,31,35]. There has been some controversy in the literature on whether neuronal activation should be monitored with Hb, HbO 2 , Oxygenation (HbO 2 -Hb), or total Hb (THb = HbO 2 + Hb) [1,7,10,11,15,24,27,28,[32][33][34]36]. While most of these studies stress that HbO 2 reflects neuronal activation more reliably and consistently, some others have shown that this effect is only global.…”

Section: Measurementsmentioning

confidence: 99%

“…We have also observed similar changes during the course of the whole experiment. Such variability or even the absence of the expected cognitive response may be attributed to the differences in the cerebrovascular physiology, attention level, and habituation of the subject [10,33,34].…”

Section: Temporal Iid Conditionsmentioning

confidence: 99%

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Extraction of cognitive activity-related waveforms from functional near-infrared spectroscopy signals

2006

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We address the problem of prototypical waveform extraction in cognitive experiments using functional near-infrared spectroscopy (fNIRS) signals. These waveform responses are evoked with visual stimuli provided in an oddball type experimental protocol. As the statistical signal-processing tool, we consider the linear signal space representation paradigm and use independent component analysis (ICA). The assumptions underlying ICA is discussed in the light of the signal measurement and generation mechanisms in the brain. The ICA-based waveform extraction is validated based both on its conformance to the parametric brain hemodynamic response (BHR) model and to the coherent averaging technique. We assess the intra-subject and inter-subject waveform and parameter variability.

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Study of local cerebral hemodynamics by frequency-domain near-infrared spectroscopy and correlation with simultaneously acquired functional magnetic resonance imaging

Cited by 70 publications

References 19 publications

A spatial and temporal comparison of hemodynamic signals measured using optical and functional magnetic resonance imaging during activation in the human primary visual cortex

A spatial and temporal comparison of hemodynamic signals measured using optical and functional magnetic resonance imaging during activation in the human primary visual cortex

Diffuse Optical Imaging

Extraction of cognitive activity-related waveforms from functional near-infrared spectroscopy signals

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