What is the advantage over other analytical methods?
Stiebing: Unlike fluorescence spectroscopy, for example, Raman spectroscopy does not need dyes to achieve coloration. We can also bypass the typical histological staining of ex vivo slices and have been able to demonstrate that we can identify the individual layers of the retina based on cross sections. This makes Raman spectroscopy a method that can also be used for in vivo diagnosis.
Compared to other retinal examination methods, Raman spectroscopy also provides additional, detailed biochemical information, while standard tests such as optical coherence tomography (OCT) primarily diagnose morphological changes. Raman spectroscopy thus gives physicians information that was not previously available.
Where does the idea of examining the retina come from?
Jahn: Scientific literature suggests that there are biochemical changes in the early stages of retinal disease that do not lead to any structural change. Raman spectroscopy provides information on the biochemical composition of biological tissues, making it a method that could visualize these changes. Like the brain, the retina is made up of nervous tissue. The optic nerve is a group of nerve fibers that connect the eye to the brain. Hence, the hypothesis is that progressive neurodegenerative diseases such as Alzheimer's disease also manifest in the retina. There is increasing evidence of this in scientific literature.
That is why the idea behind the MOON project was to combine the advantages of standard optical coherence tomography (OCT) with Raman spectroscopy to create a comprehensive, detailed view of the retina.
A device that combines Raman spectroscopy with OCT is currently in development. What is your role in this process?
Stiebing: Our project partners at the Medical University of Vienna have applied for device approval, which should be accepted soon. The device can subsequently be tested in vivo on the first patients. We continue to collaborate closely together and leverage our expertise in Raman spectroscopy analysis in hopes that this will also shed light on the diagnostic benefits.