1. A computer aided diagnostic system, comprising: a data storage configured to receive optical tomographic data representing interrogated tissues of a living animal; a processor configured to retrieve said optical tomographic data from said data storage and estimate volumetric properties of the living animal, said processor being further configured to output display data and/or classification data representing said volumetric properties and/or classifying clinical features of said living animal, wherein the processor is configured to execute instructions to estimate said properties using a method for performing a partial differential equation (PDE)-constrained reduced Hessian sequential quadratic programming (rSQP) optimization in which a constraint is defined by a simplified spherical harmonics approximation of the equation of radiative transfer.