An Inverse Method for the Recovery of Tissue Parameters from Colour Images

Abstract

Abstract. The interpretation of colour images is presented as an inverse problem in which a mapping is sought between image colour vectors and the physiological parameters characterizing a tissue. To ensure the necessary oneto-one correspondence between the image colours and the parameters, the mapping must be unique. This can be established through testing the sign of the determinant of the Jacobian matrix, a multi-dimensional equivalent of a discrete derivative, over the space of all parameter values. Furthermore, an optimisation procedure is employed to find the set of filters for image capture which generate image vectors minimizing the mapping error. This methodology applied to interpretation of skin images shows that the standard RGB system of filters provides for a unique mapping between image values and parameters characterizing the normal skin. It is further shown that an optimal set of filters reduces the error of quantification by a factor of 2, on average.

New closed-form approximation for skin chromophore mapping

“…[12][13][14] It is relatively easy to include the absorption of all important skin chromophores and scattering factors into the model. Notwithstanding the long simulation times, the model has been used for many purposes, such as in the development of the pulse oximeter, 15 melanoma diagnostics, [16][17][18] melanin-and bloodconcentration measurements, 19,20 skin-treatment planning, 21 and determination of the information depth of the skin reflectance. 22 Another often-used method for modeling light transport in skin is the diffusion approximation of the light transport equation.…”

Shape-based multi-spectral optical image reconstruction through genetic algorithm based optimization

“…For instance, Claridge and Preece [8] used a Kubelka-Munk model to simulate the formation of the image of melanoma and presented a method to recover blood and melanin distribution in various skin layers. However, KubelkaMunk model is theoretically established in one-dimensional system with point-based measurements.…”

Desenvolvimento e resultados preliminares de um sistema cromático de iluminação para oftalmoscópios indiretos

“…Um amplo número de técnicas é aplicado com o intuito de analisar imagens biológicas, muitas das quais foram inicialmente desenvolvidas para aplicações de propósito dermatológico (2)(3)(4) . Estudos posteriores têm destacado órgãos internos, particularmente o fígado, que é de grande interesse em estudos bioquímicos e patológicos, devido sua importância em muitas reações metabólicas (5)(6) .…”