A fundamental limitation of linearized algorithms for diffuse optical tomography.

Diffuse Optical Tomography is rapidly developing as a new imaging modality for characterizing the spatially varying optical properties of media which strongly scatter light (e.g. tissue). Numerous imaging algorithms exist, and more are being developed. Many of these algorithms rely on assumptions which linearize the relationship between the optical contrast and the perturbed signal. We show that this linear approximation makes quantitative imaging of spatially varying optical properties impossible. The explanation for this result is presented and the implication for Diffuse Optical Tomography is discussed.