Perturbation Monte-Carlo based derivative estimation for imaging low-scattering inclusions in a heterogeneous tissue

For near infrared imaging of the neonatal head surrounded by the cerebrospinal fluid layer, we have developed an imaging modality which uses perturbation Monte-Carlo estimation of the Jacobian of the forward model for photon propagation. We have shown that conventional techniques, which use a diffusion approximation for light transport in tissue, fails to give the reconstruction of tissue optical properties. We were able to successfully reconstruct both scattering and absorption inhomogeneities in objects which fall under the transport regime. Results of numerical simulation are presented.