Bayer Filter Snapshot Hyperspectral Fundus Camera for Human Retinal Imaging

ABSTRACT

Purpose: To demonstrate the versatility and performance of a compact Bayer filter snapshot hyperspectral fundus camera for in-vivo clinical applications including retinal oximetry and macular pigment optical density measurements.

Methods: 12 healthy volunteers were recruited under an Institutional Review Board (IRB) approved protocol. Fundus images were taken with a custom hyperspectral camera with a spectral range of 460–630 nm. We determined retinal vascular oxygen saturation (sO₂) for the healthy population using the captured spectra by least squares curve fitting. Additionally, macular pigment optical density was localized and visualized using multispectral reflectometry from selected wavelengths.

Results: We successfully determined the mean sO₂ of arteries and veins of each subject (ages 21–80) with excellent intrasubject repeatability (1.4% standard deviation). The mean arterial sO₂ for all subjects was 90.9% ± 2.5%, whereas the mean venous sO₂ for all subjects was 64.5% ± 3.5%. The mean artery–vein (A–V) difference in sO₂ varied between 20.5% and 31.9%. In addition, we were able to reveal and quantify macular pigment optical density.

Conclusions: We demonstrated a single imaging tool capable of oxygen saturation and macular pigment density measurements in vivo. The unique combination of broad spectral range, high spectral–spatial resolution, rapid and robust imaging capability, and compact design make this system a valuable tool for multifunction spectral imaging that can be easily performed in a clinic setting.

KEYWORDS:

• Hyperspectral fundus imaging
• oximetry
• macular pigment
• spectroscopy

Funding

This work was supported by funding from the National Institute of Health (1R01EY021470 (A.A. Fawzi), 1R01EY019951(A.A. Fawzi and H.F. Zhang)), the National Science Foundation (CBET-1055379), and the Illinois Society for Prevention of Blindness (J. Kaluzny).

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Additional information

Funding

This work was supported by funding from the National Institute of Health (1R01EY021470 (A.A. Fawzi), 1R01EY019951(A.A. Fawzi and H.F. Zhang)), the National Science Foundation (CBET-1055379), and the Illinois Society for Prevention of Blindness (J. Kaluzny).