Associations Between Retinal Layers and the Brain

Article: The Retina as a Possible Biomarker for Reduced Brain Matter
Source: University of Bonn (Germany)
Published: March 16, 2022
Article: The Retina as a Possible Biomarker for Reduced Brain Matter
Source: German Center for Neurodegenerative Diseases (Germany)
Published: March 15, 2022

SD-OCT of the retina

The retina is an extension of the brain and as such shares many neurological characteristics of brain matter. Researchers in Germany further explored the similarities between the two tissues as a means of using retinal imaging to assess potential biomarkers of brain atrophy. Called the Rhineland Study, this study involved almost 2,872 subjects who participated in retinal scans via spectral domain optical coherence tomography (SD-OCT) and brain scans via magnetic resonance imaging (MRI). Compared to techniques used in earlier studies, SD-OCT is a newer retinal imaging technology and allowed for more detailed imaging of all the retinal layers. The researchers then used computer software to compare the thickness and volume of the various retinal layers with the thickness and volume of brain structures. They found a close positive association between the volume (and microstructural integrity, as assessed by fractional anisotropy) of the inner retinal layers and the so-called white matter of the brain. By contrast, the outer retinal layers were associated with the brain's gray matter. These associations were particularly pronounced in the occipital lobe, where visual processing takes place, and, interestingly, also with volume of the hippocampus where memory is formed and is an area often affected in dementia. Because retinal scans are noninvasive, quick, and relatively accessible, they could be an easy method to detect and monitor brain atrophy and the progression of neurological degenerative diseases. The researchers next plan to expand their studies to larger patient groups and over longer periods to verify the results in clinical settings.

My rating of this study: ⭐⭐

Mauschitz MM, Lohner V, Koch A, et al. "Retinal layer assessments as potential biomarkers for brain atrophy in the Rhineland Study." Scientific Reports.  12:2757. 17 February 2022. https://doi.org/10.1038/s41598-022-06821-4