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New retinal test for early Alzheimer's disease

  • A new test can quickly detect reduced blood capillaries in the back of the eye that are an early indication of Alzheimer's, and shows that it can help distinguish Alzheimer's from MCI.

A study has shown new technology can quickly and non-invasively detect reduced blood capillaries in the back of the eye that are an early indication of Alzheimer's. It also shows that these signs can help distinguish between Alzheimer's and MCI.

The study compared the retinas of 39 Alzheimer's patients, 37 people with MCI, and 133 cognitively healthy people. The Alzheimer's group had loss of small retinal blood vessels at the back of the eye and a specific layer of the retina was thinner when compared to people with MCI and healthy people. The differences in density were statistically significant after researchers controlled for factors including age and sex.

It's been known that patients with Alzheimer's had decreased retinal blood flow and vessel density but it had not been known if these changes were also present in individuals with early Alzheimer's or aMCI.

Larger datasets are required to validate the marker.

https://www.eurekalert.org/pub_releases/2019-04/nu-ere040519.php

https://www.eurekalert.org/pub_releases/2019-03/aaoo-nss030719.php

Reference

Zhang, Y. S., Zhou, N., Knoll, B. M., Samra, S., Ward, M. R., Weintraub, S., & Fawzi, A. A. (2019). Parafoveal vessel loss and correlation between peripapillary vessel density and cognitive performance in amnestic mild cognitive impairment and early Alzheimer’s Disease on optical coherence tomography angiography. PLOS ONE, 14(4), e0214685. Retrieved from https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0214685

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