Spectroscopic imaging of the retinal vessels using a new dual-wavelength

This study aimed to investigate the feasibility of non-invasive evaluating vessel blood oxygenation in the human eye using a dual-wavelength confocal scanning laser ophthalmoscope (cSLO). A cSLO prototype was adapted to use a new combination of two red and infrared wavelengths simultaneously performing a spectral analysis of the status of retinal blood vessel to give the ability to image perfusion in the human eye. This technique was evaluated using measurements made on normal volunteers' eyes. The reproducibility of the measurements of reflected light from the eye was investigated. Spectral measurements of light reflected from retinal vessels were determined and liner relationship of oxygen saturation of blood and spectral transmittance based on Beer-Lambert law was defined. The relative oxygen levels of retinal blood vessels (artery and vein) were successfully determined using these two wavelengths. The technique showed promise in the determination of the relative oxygen saturation levels of the retina in amongst eye subjects.

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