Combined confocal/en face optical coherence tomography imaging of the human eye fundus in vivo in the 1050 nm spectral region

摘要

The 1020-1080 nm spectral region appears as a viable alternative to the 700-900 nm spectral band for in vivo eye fundus OCT imaging due to a local absorption minimum of water (main constituent of the eye aqueous and vitreous). Light at these wavelengths also experiences less attenuation due to lower scattering and absorption by melanin in the retinal pigment epithelium and choroid, which results in deeper penetration of the probe beam in the choroid. T-scan based en face OCT is a modification of the OCT technique that has the unique capability of acquiring both longitudinal (B-scans) and tranversal (C-scans) OCT images of the eye fundus in real time and allows the addition of a confocal scanning ophthalmoscope channel to the OCT instrument. We report for the first time a combined T-scan based en face OCT and confocal scanning opthalmoscopy system for imaging the human eye fundus in vivo in the 1050 nm region. The instrument allows the visualization of choroidal blood vessels in both the confocal and OCT channels without the use of contrast agents such as indocyanine green (ICG) dye and could prove an alternative tool for diagnosing eye conditions like age related macular degeneration that are preceded by choroidal neovascularisation.