This article is part of the Research Topic Neurovascular imaging

Original Research ARTICLE

Front. Neuroenergetics, 14 July 2010 | http://dx.doi.org/10.3389/fnene.2010.00014

Brain specificity of diffuse optical imaging: improvements from superficial signal regression and tomography

  • 1 Department of Radiology, Washington University in St. Louis, MO, USA
  • 2 Department of Physics, Washington University in St. Louis, MO, USA
  • 3 The Institute of Optics, University of Rochester, Rochester, NY, USA
  • 4 Department of Biomedical Engineering, Washington University in St. Louis, MO, USA

Functional near infrared spectroscopy (fNIRS) is a portable monitor of cerebral hemodynamics with wide clinical potential. However, in fNIRS, the vascular signal from the brain is often obscured by vascular signals present in the scalp and skull. In this paper, we evaluate two methods for improving in vivo data from adult human subjects through the use of high-density diffuse optical tomography (DOT). First, we test whether we can extend superficial regression methods (which utilize the multiple source–detector pair separations) from sparse optode arrays to application with DOT imaging arrays. In order to accomplish this goal, we modify the method to remove physiological artifacts from deeper sampling channels using an average of shallow measurements. Second, DOT provides three-dimensional image reconstructions and should explicitly separate different tissue layers. We test whether DOT’s depth-sectioning can completely remove superficial physiological artifacts. Herein, we assess improvements in signal quality and reproducibility due to these methods using a well-characterized visual paradigm and our high-density DOT system. Both approaches remove noise from the data, resulting in cleaner imaging and more consistent hemodynamic responses. Additionally, the two methods act synergistically, with greater improvements when the approaches are used together.

Keywords: neuroimaging, biomedical optics, near-infrared spectroscopy, diffuse optical tomography, artifact removal, image quality

Citation: Gregg NM, White BR, Zeff BW, Berger AJ and Culver JP (2010) Brain specificity of diffuse optical imaging: improvements from superficial signal regression and tomography. Front. Neuroenerg. 2:14. doi: 10.3389/fnene.2010.00014

Received: 26 February 2010; Paper pending published: 30 March 2010;
Accepted: 11 June 2010; Published online: 14 July 2010

Edited by:

David Boas, Massachusetts General Hospital, USA; Massachusetts Institute of Technology, USA; Harvard Medical School, USA

Reviewed by:

Jens Steinbrink, Charité - Universitätsmedizin Berlin, Germany
Yueli Chen, University of Connecticut, USA

Copyright: © 2010 Gregg, White, Zeff, Berger and Culver. This is an open-access article subject to an exclusive license agreement between the authors and the Frontiers Research Foundation, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are credited.

*Correspondence: Joseph P. Culver, Department of Radiology, Optical Radiology Laboratory, Washington University in St. Louis, 4525 Scott Avenue, Box 8225, St. Louis, MO 63110, USA. e-mail: culverj@wustl.edu