Spatially weighted BOLD signal for comparison of functional magnetic resonance imaging and near-infrared imaging of the brain

We introduce a weighted spatial average of the functional magnetic resonance imaging (fMRI) BOLD signal (blood oxygen level-dependent) that is appropriate for comparison with the changes in oxy- and deoxy-hemoglobin concentrations measured with near-infrared spectroscopy (NIRS) during brain activation. Because the BOLD signal shows a spatial dependence (both in shape and amplitude) within the region of activation, the location of the optical probe with respect to the region of BOLD activation should be taken into account for comparison of the BOLD and NIRS signals. Our new method is based on combining weighted contributions of the BOLD signal from each activated voxel, with a weight given by a hitting density function for photons migrating between a given pair of illumination and collection points. We present a case study where we have found that the new spatially weighted BOLD signal shows a high spatial and temporal correlation with the oxy- and deoxy-hemoglobin concentration changes measured with NIRS during a hand-tapping protocol. These findings reinforce the idea that fMRI and NIRS are sensitive to similar underlying hemodynamic changes, and indicate that the proposed weighted BOLD signal is needed for a quantitative comparison of BOLD and NIRS signals.

[1]  Egill Rostrup,et al.  Determination of relative CMRO2 from CBF and BOLD changes: Significant increase of oxygen consumption rate during visual stimulation , 1999, Magnetic resonance in medicine.

[2]  Satoru Miyauchi,et al.  Circulatory basis of fMRI signals: relationship between changes in the hemodynamic parameters and BOLD signal intensity , 2004, NeuroImage.

[3]  J. Haselgrove,et al.  Photon hitting density. , 1993, Applied optics.

[4]  Ravi S. Menon,et al.  Functional brain mapping by blood oxygenation level-dependent contrast magnetic resonance imaging. A comparison of signal characteristics with a biophysical model. , 1993, Biophysical journal.

[5]  David A Boas,et al.  Temporal comparison of functional brain imaging with diffuse optical tomography and fMRI during rat forepaw stimulation , 2003, Physics in medicine and biology.

[6]  Thomas T. Liu,et al.  Discrepancies between BOLD and flow dynamics in primary and supplementary motor areas: application of the balloon model to the interpretation of BOLD transients , 2004, NeuroImage.

[7]  S. Fantini,et al.  Comment on the modified Beer-Lambert law for scattering media. , 2004, Physics in medicine and biology.

[8]  M. Mintun,et al.  Nonoxidative glucose consumption during focal physiologic neural activity. , 1988, Science.

[9]  E. Gratton,et al.  On-line optical imaging of the human brain with 160-ms temporal resolution. , 2000, Optics express.

[10]  Atsushi Maki,et al.  Simultaneous Recording of Event-Related Auditory Oddball Response Using Transcranial Near Infrared Optical Topography and Surface EEG , 2002, NeuroImage.

[11]  E. Gratton,et al.  Study of local cerebral hemodynamics by frequency-domain near-infrared spectroscopy and correlation with simultaneously acquired functional magnetic resonance imaging. , 2001, Optics express.

[12]  Valery V. Tuchin,et al.  OPTICAL BIOMEDICAL DIAGNOSTICS , 2004 .

[13]  David A. Boas,et al.  Factors affecting the accuracy of near-infrared spectroscopy concentration calculations for focal changes in oxygenation parameters , 2003, NeuroImage.

[14]  Martin Wolf,et al.  Different Time Evolution of Oxyhemoglobin and Deoxyhemoglobin Concentration Changes in the Visual and Motor Cortices during Functional Stimulation: A Near-Infrared Spectroscopy Study , 2002, NeuroImage.

[15]  D. Delpy,et al.  Use of the water absorption spectrum to quantify tissue chromophore concentration changes in near-infrared spectroscopy. , 1994, Physics in medicine and biology.

[16]  M. Tamura,et al.  Detection of dynamic changes in cerebral oxygenation coupled to neuronal function during mental work in man , 1993, Neuroscience Letters.

[17]  A Maki,et al.  Wavelength dependence of the precision of noninvasive optical measurement of oxy-, deoxy-, and total-hemoglobin concentration. , 2001, Medical physics.

[18]  J. Mandeville,et al.  The Accuracy of Near Infrared Spectroscopy and Imaging during Focal Changes in Cerebral Hemodynamics , 2001, NeuroImage.

[19]  F. Martelli,et al.  Penetration depth of light re-emitted by a diffusive medium: theoretical and experimental investigation. , 2002, Physics in medicine and biology.

[20]  B. Chance,et al.  A novel method for fast imaging of brain function, non-invasively, with light. , 1998, Optics express.

[21]  J. R. Baker,et al.  The intravascular contribution to fmri signal change: monte carlo modeling and diffusion‐weighted studies in vivo , 1995, Magnetic resonance in medicine.

[22]  E. Gratton,et al.  Near-infrared study of fluctuations in cerebral hemodynamics during rest and motor stimulation: temporal analysis and spatial mapping. , 2000, Medical physics.

[23]  H J Hiddinga,et al.  Viroid-induced phosphorylation of a host protein related to a dsRNA-dependent protein kinase. , 1988, Science.

[24]  B. Chance,et al.  Photon migration in the presence of a single defect: a perturbation analysis. , 1995, Applied optics.

[25]  Vlad Toronov,et al.  The roles of changes in deoxyhemoglobin concentration and regional cerebral blood volume in the fMRI BOLD signal , 2003, NeuroImage.

[26]  R. Buxton,et al.  A Model for the Coupling between Cerebral Blood Flow and Oxygen Metabolism during Neural Stimulation , 1997, Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism.

[27]  Sergio Fantini,et al.  A haemodynamic model for the physiological interpretation of in vivo measurements of the concentration and oxygen saturation of haemoglobin. , 2002, Physics in medicine and biology.

[28]  David A. Boas,et al.  A Quantitative Comparison of Simultaneous BOLD fMRI and NIRS Recordings during Functional Brain Activation , 2002, NeuroImage.

[29]  E. Gratton,et al.  Non-invasive optical monitoring of the newborn piglet brain using continuous-wave and frequency-domain spectroscopy. , 1999, Physics in medicine and biology.

[30]  Toshinori Kato,et al.  Paradoxical correlation between signal in functional magnetic resonance imaging and deoxygenated haemoglobin content in capillaries: a new theoretical explanation , 2002 .

[31]  Atsushi Maki,et al.  Non-invasive assessment of language dominance with near-infrared spectroscopic mapping , 1998, Neuroscience Letters.

[32]  R. Buxton,et al.  Modeling the hemodynamic response to brain activation , 2004, NeuroImage.

[33]  Hellmuth Obrig,et al.  Separability and cross talk: optimizing dual wavelength combinations for near-infrared spectroscopy of the adult head , 2004, NeuroImage.

[34]  R. Buxton,et al.  Dynamics of blood flow and oxygenation changes during brain activation: The balloon model , 1998, Magnetic resonance in medicine.