Purpose:
To use a hyperspectral imaging (HSI) system as a non-invasive method to measure oxygen delivery to the optic nerve head (ONH) and retinal vessels in human subjects.
Methods:
Fundus images of the optic nerve head, retina, and their overlying vessels were obtained from healthy human subjects using the HSI system. Reflectance light spectroscopy under constant illumination of ONH and retinal areas was performed with HSI. Reflectance oxyhemoglobin and deoxyhemoglobin spectral curves were generated from light reflected from each region of interest at wavelengths ranging from 409 nm to 917 nm. A predetermined algorithm was used to calculate the relative oxygen saturation indices from the different structures.
Results:
The relative saturation indices for the arteriole, venule, and ONH areas were found to be as follows: 3.1, 2.4, and 4.7.
Conclusions:
This study non-invasively measures oxygen saturation levels in the eyes of human subjects. We believe that this novel non-invasive approach to measuring the oxygen levels in the ocular structures of human subjects will contribute to our understanding of how oxygen is provided and used by the eye.
Keywords: oxygen • retina • imaging/image analysis: clinical