Multi-frequency diffuse optical tomography for cancer detection

Previous work has validated that the accuracy of absorption coefficient can be improved using frequency-domain (FD) DOT measurements with multiple modulation frequencies. In this paper, we investigate the use of multi-frequency FD-DOT to improve the recovery accuracy of scattering coefficient, which is of great interest to cancer study. A new method called the clustered sparsity reconstruction (CSR) is proposed to reconstruct the absorption and scattering coefficients jointly. We conduct numerical simulations for FD-DOT image reconstruction with multi-modulation frequencies. The numerical results show that the recovery accuracy of scattering coefficient can be significantly improved using multi-frequency data and the proposed CSR method. It is interesting to demonstrate that the combination of two modulation frequencies results in the best reconstruction accuracy in terms of contrast-to-noise ratio (CNR) and root-mean-square error (RMSE), while more number of modulation frequencies does not improve the image quality much.