Tomographic fluorescence imaging in tissue phantoms: a novel reconstruction algorithm and imaging geometry.
A novel image reconstruction algorithm has been developed and demonstrated for fluorescence-enhanced frequency-domain photon migration (FDPM) tomography from measurements of area illumination with modulated excitation light and area collection of emitted fluorescence light using a gain modulated image-intensified charge-coupled device (ICCD) camera. The image reconstruction problem was formulated as a nonlinear least-squares-type simple bounds constrained optimization problem based upon the penalty/modified barrier function (PMBF) method and the coupled diffusion equations. The simple bounds constraints are included in the objective function of the PMBF method and the gradient-based truncated Newton method with trust region is used to minimize the function for the large-scale problem (39919 unknowns, 2973 measurements). Three-dimensional (3-D) images of fluorescence absorption coefficients were reconstructed using the algorithm from experimental reflectance measurements under conditions of perfect and imperfect distribution of fluorophore within a single target. To our knowledge, this is the first time that targets have been reconstructed in three-dimensions from reflectance measurements with a clinically relevant phantom.
Roy
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The Photon Migration Laboratories, Texas A&M University, College Station, TX 77843-3573, USA. rroy@mail.chem.tamu.edu
Thompson
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Godavarty
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Sevick-Muraca
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EM
D000465:Algorithms; D000818:Animals; D001185:Artificial Intelligence; D003238:Connective Tissue / Q000648:ultrastructure*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008856:Microscopy, Fluorescence / Q000295:instrumentation / Q000379:methods*; D009716:Numerical Analysis, Computer-Assisted; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted; D013055:Spectrophotometry, Infrared / Q000295:instrumentation / Q000379:methods*; D041622:Tomography, Optical / Q000295:instrumentation / Q000379:methods*