Excitation spectroscopy in multispectral optical fluorescence tomography_ methodology, feasibility puter simulation studies.pdf

IOP PUBLISHING PHYSICS IN MEDICINE AND BIOLOGY
Phys. Med. Biol. 54 (2009) 4687–4704 doi:-9155/54/15/004
Excitation spectroscopy in multispectral optical
fluorescence tomography: methodology, feasibility
puter simulation studies
Abhijit J Chaudhari1,2, Sangtae Ahn3, Richard Levenson4,
Ramsey D Badawi2, Simon R Cherry1 and Richard M Leahy3
1 Department of Biomedical Engineering, University of California-Davis, Davis, CA 95616, USA
2 Department of Radiology, UC Davis Medical Center, Sacramento, CA 95817, USA
3 Signal and Image Processing Institute, University of Southern California, Los Angeles,
CA 90089, USA
4 Cambridge Research Instruments, Inc., Woburn, MA 01801, USA
E-mail: ******@ and ******@
Received 12 February 2009, in final form 11 June 2009
Published 10 July 2009
Online at stacks./PMB/54/4687
Abstract
Molecular probes used for in vivo optical fluorescence tomography (OFT)
studies in small animals are typically chosen such that their emission spectra lie
in the 680–850 nm wavelength range. This is because tissue attenuation in this
spectral band is relatively low, allowing optical photons even from deep sites
in tissue to reach the animal surface and consequently be detected by D
camera. The wavelength dependence of tissue optical properties within the
680–850 nm band can be exploited for emitted light by measuring fluorescent
data via multispectral approaches and incorporating the spectral dependence of
these optical properties into the OFT inverse problem—that of reconstructing
underlying 3D fluorescent probe distributions from optical data collected on
the animal surface. However, in the aforementioned spectral band, due to
only small variations in the tissue optical properties, multispectral emission
data, though superior for image pared to achromatic data,
tend to be somewhat redundant. A different spectral approach for OFT is
to capitalize on the larger variations