Eyeworld

EW NEWS & OPINION December 2015 21 "The retina is the only place in the body where we can visually analyze the health and function of the systemic vasculature," he said. "Therefore, I think that this is cer- tainly a possibility." That said, when asked if he thinks there might be a role for ophthalmologists to play in fighting dementia, outside of their direct spe- cialty, he responded: "Possibly, but that would be more unlikely." EW References 1. Coppola G, et al. Optical coherence tomog- raphy in Alzheimer's disease: A meta-analysis. PloS One. 2015 Aug 7;10(8):e0134750. 2. Gao L, et al. Neuroprotective effect of memantine on the retinal ganglion cells of APPswe/PS1ΔE9 mice and its immunomod- ulatory mechanisms. Exp Eye Res. 2015 Jun;135:47–58. 3. Gao L, et al. Abnormal retinal nerve fiber layer thickness and macula lutea in patients with mild cognitive impairment and Alzheimer's disease. Arch Gerontol Geriatr. 2015 Jan-Feb;60(1):162–7. 4. Ong Y, et al. Retinal neurodegeneration on optical coherence tomography and cerebral atrophy. Neurosci Lett. 2015 Jan 1;584:12–6. Editors' note: Drs. Coppola, Gao, and Ong have no financial interests related to their studies. Dr. Schimel has no financial interests related to his comments. Contact information Coppola: gianluca.coppola@gmail.com Gao: glx919@163.com Ong: ong.yi.ting@nus.edu.sg Schimel: aschimel@gmail.com visual impairments" in mice, "mak- ing MEM a potential ophthalmic treatment alternative in patients with AD." Although his results were not cited in Dr. Coppola's meta-analysis, Dr. Gao also found in the January/ February issue of Archives of Geron- tology and Geriatrics that "retinal de- generation in AD and MCI patients results in decreased thickness of the RNFL." South of China, in Singapore, researchers there published results in Neuroscience Letters in January 2015 based on Malay patients who under- went OCT scanning. Interestingly, here OCT scans were also correlated with MRI scans. So while RNFL and GC-IPL (ganglion cell-inner plexiform layer) thicknesses were ascertained via OCT, cerebral grey and white matter volumes were being assessed by MRI. "Retinal neuronal damage, as reflected by GC-IPL thinning, was independently associated with grey matter loss in the occipital and temporal lobes, suggesting that retinal OCT may provide insights for assessing neurodegeneration in the brain," according to Yi-Ting Ong, a researcher at the Singapore Eye Research Institute. Back in the U.S., Andrew Schimel, MD, surgical and medi- cal vitreoretinal specialist, Center for Excellence in Eye Care, Miami, agreed that in the future, analyzing the retina could help diagnose con- ditions like Alzheimer's. " Multiple forms of evidence points toward the involvement of retinal ganglion cells and their axons in the optic nerve as a basis of the visual dysfunction in Alzheimer's disease. " –Gianluca Coppola, MD

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