Investigation of reflectance sampling depth in biological tissues for various common illumination/collection configurations.

Knowledge of light penetration characteristics is very important in almost all studies in biomedical optics. In this work, the reflectance sampling depth in biological tissues was investigated using Monte Carlo simulations for various common illumination/collection configurations. The analysis shows that the average sampling depth can be described by two simple empirical analytical expressions over the entire typical ranges of absorption and scattering properties relevant to in vivo biological tissue, regardless of the specific illumination/collection configuration details.

Reflectance model for acetowhite epithelium.

Application of low concentration acetic acid solution to various types of human epithelia, in vivo, is a well-established technique for the visual identification of neoplastic and potential precancerous lesions, especially in the cervix. An acetic acid application produces a transient whitening effect associated with the aforementioned lesions (acetowhite effect). In this article, a simple semi-empirical tissue reflectance model is presented, which describes the acetowhite effect in terms of the tissue's optical properties and layered structure.

Modeling diffuse reflectance from homogeneous semi-infinite turbid media for biological tissue applications: a Monte Carlo study.

Diffuse reflectance spectroscopy is one of the simplest and widely used techniques for the non-invasive study of biological tissues but no exact analytical solution exists for the problem of diffuse reflectance from turbid media such as biological tissues. In this work, a general treatment of the problem of diffuse reflectance from a homogeneous semi-infinite turbid medium is presented using Monte Carlo simulations. Based on the results of the Monte Carlo method, simple semi-empirical analytical solutions are developed valid for a wide range of collection geometries corresponding to various optical detector diameters.

Simple two-layer reflectance model for biological tissue applications: lower absorbing layer.

A simple two-layer tissue reflectance model is described. This work is a continuation of our investigations on modeling reflectance from two-layered tissues that we recently initiated. In the present article, we describe a variation of a two-layer model that assumes a lower absorbing and scattering layer and an upper scattering-only layer.

Noise and stray light characterization of a compact CCD spectrophotometer used in biomedical applications.

In recent years, new generation spectrophotometers are increasingly used in biomedical applications. Handheld spectrophotometers, offering compactness, versatility, and low cost, have facilitated a broad array of applications in biomedical optics. However, despite the popularity and the diverse range of applications, a detailed characterization of many of these new spectrophotometers in terms of stray light and noise characteristics is missing from the literature.