Multispectral retinal video‐ophthalmoscope with fiber optic illumination

Abstract

Multispectral imaging is used in various applications including astronomy, industry and agriculture. In retinal imaging, the single-shot multispectral image stack is typically acquired and analyzed. This multispectral analysis can provide information on various structural or metabolic properties. This paper describes the multispectral improvement of a videoophthalmoscope, which can acquire retinal video sequences of the optic nerve head and peripapillary area using various spectral light illumination. The description of the multispectral video imaging is provided and several applications are described. These applications include multispectral retinal photoplethysmography, visualization of spontaneous vein pulsation and multispectral RGB image generation.

Assessment of retinal vein pulsation through video-ophthalmoscopy and simultaneous biosignals acquisition

“…Video-ophthalmoscope (VO) – The monocular video-ophthalmoscope is based on our previous research on binocular video-ophthalmoscopy [ 1 , 2 ]. The setup of the version used in the previous work was modified to a monocular version with the possibility of multispectral measurement [ 22 ]. This device acquires retinal video of the optic nerve head and the peripapillary area with a field of view of 20° × 17° (1224 × 970 pixels).…”

“…The fundus image with a clinical fundus camera (Canon CR-1 with Canon EOS 40D). During measurement with a video-ophthalmoscope, we used various wavelengths [ 22 ], but here we analyzed video sequences, which were acquired with 525 nm. Light with this wavelength provides a good contrast of the blood vessels.…”

“…Frame-to-frame alignment – The previously published approach [ 22 ] was used to align each frame with respect to the first frame (i.e. reference).…”

“…This approach corrects for translational and rotational movements using a combination of phase correlation and tracking of the center lines of the blood vessels. The registration error of this approach is 0.78 ± 0.67 pixels inside the optic disc and 1.39 ± 0.63 pixels outside the optic disc, respectively [ 22 ].…”

1st Spring Biophotonics Conference in Porto

“…Kolar et al describe the improvement made to a multispectral video‐ophtalmoscope so that it can acquire video sequences of the optic nerve head and peripapillary area of the eye when illuminated with various LED sources with emission spectra within the visible range [1]. Some applications of this improved instrument, such as multispectral retinal photoplethysmography, visualization of spontaneous vein pulsation, and multispectral RGB image generation are presented and discussed in the paper.…”