RGB Camera-Based Imaging of Oxygen Saturation and Hemoglobin Concentration in Ocular Fundus

Abstract

We propose a red, green, blue (RGB)-based oximetry to assess the ocular fundus and determine its oxygen saturation (SO2) and hemoglobin concentration. The oxygenated hemoglobin concentration, deoxygenated hemoglobin concentration, and SO2 were estimated employing a method that combines Monte Carlo simulation of light transport in the fundus tissue with a multiple regression analysis. In this study, a single-layer model of the ocular fundus was employed for the Monte Carlo simulation. We constructed an experimental apparatus for measuring the fundus of a rat's eye using an RGB detector and investigated the physiological response that occurs upon a change in the fraction of inspired oxygen (FiO2). The resultant images of oxygenated hemoglobin concentration, deoxygenated hemoglobin concentration, total hemoglobin concentration, and SO2 indicated that the response was caused by the defective oxygenation of the blood. The results of the present study indicate the possibility of oximetry based on the RGB images of a fundus.