Optical filters in medical imaging to improve diagnosis

Abstract

Optical filters improve medical imaging diagnosis by enhancing image contrast and resolution. They block unwanted light and reflections aiming to block interferences, aiming to sharpen the images, to increase contrast and reveal fine details that might be otherwise obscured. Filters can be combined with other imaging methods to provide detailed information and can make a difference in neonatal care, where the use of contrast substances during investigations should be avoided. We combined wavelets and a contrast enhancement algorithm based on histogram equalizing algorithms, which aim to adjust the contrast of the image by modifying the intensity distribution of its histogram, on children lung histograms. Parameters such as contrast factor, clip limit or tile size have been taken into consideration. We noticed that low clip values preserve fine lung textures, being good for fibrosis detection. The proposed algorithm spreads out the most frequent intensity values to enhance areas of lower local contrast. The results are displayed graphically to enable any physician an accurate interpretation of the algorithm’s performances.