Optical tomography: seeing inside the body

Abstract

The passage of infrared light through biological tissue is essentially a diffusion process. Our goal is to reconstruct the diffusion coefficients inside a volume of tissue. Light pulses are incident onto a volume, and light intensity measurements are taken of the time-dependent responses around the surface of that volume. The analysis is a difficult problem. Our approach is to invert the diffusion equation by using a numerical technique called adjoint differentiation. This technique is generally applicable to deterministic problems that can be modeled numerically by simulation computer codes.

References

• "Model-based image reconstruction from time-resolved diffusion data," S. S. Saquib, et al., Proc. SPIE 3034, pp. 369-380 (1997)
• "Inversion based on computational simulations" K. M. Hanson, et al., in Maximum Entropy and Bayesian Methods, pp. 121-135 (Kluwer Academic, Dordrecht, 1998)
• "Tomographic imaging of biological tissue by time-resolved, model-based, iterative image reconstruction," A. H. Hielscher et al., in Proc. Adv. Opt. Imag. and Phot. Migr (OSA, 1998)
• "Gradient-based iterative image reconstruction scheme for time-resolved optical tomography," A.H. Hielscher et al., IEEE Trans. Med. Imag. 18, pp. 1-10, 1999
• "Two- and three-dimensional optical tomography of finger joints for diagnostics of rheumatoid arthritis," A. D. Klose et al., Proc. SPIE 3566 (1998)

Keywords: optical tomography, diffusion of infrared light, adjoint differentiation, inversion of numerical simulations

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