Contrast sensitivity is a useful measure of the ability of an observer to distinguish contrast signals from noise. Although usually applied to human observers, contrast sensitivity can also be defined operationally for individual visual neurons. In a model linear neuron consisting of a filter and noise source, this operational measure is a function of filter gain, noise power spectrum, signal d...

PURPOSE To compare the measurement of contrast sensitivity at a distance in patients submitted to penetrating keratoplasty versus patients submitted to deep anterior lamellar keratoplasty for keratoconus treatment. METHODS Contrast sensitivity of fourteen subjects submitted to penetrating keratoplasty and fourteen subjects submitted to deep anterior lamellar keratoplasty have been analyzed th...

Measuring the contrast sensitivity function (CSF) in the periphery of the eye is complicated. The lengthy measurement time precludes all but the most determined subjects. The aim of this study was to implement and evaluate a faster routine based on the quick CSF method (qCSF) but adapted to work in the periphery. Additionally, normative data is presented on neurally limited peripheral CSFs. A p...

introduction: although extensive research has been conducted on lung cancer markers, a singular clinically applicable marker has not been found yet. the objective of this study was to evaluate the sensitivity and the specificity of carcinoembryonic antigen (cea) mrna and lung-specific x protein (lunx) mrna biomarkers in peripheral blood to detect lung cancer individually and simultaneously. met...