When compared with patients with mild cognitive impairment and control subjects, patients with Alzheimer’s disease exhibited significantly reduced macular vessel density, perfusion density and ganglion cell-inner plexiform layer thickness, according to a study.
“Our findings are important because they suggest that one day we may have an inexpensive, quick and noninvasive way to screen asymptomatic persons for Alzheimer’s and then enter them into clinical trials studying novel therapeutics, which may be more effective earlier in the disease process. We may then be able to find a way to delay the onset of, prevent the development of or even reverse Alzheimer’s,” study co-authors Sharon Fekrat, MD, and Dilraj S. Grewal, MD, told Healio.com/OSN.
The cross-sectional study compared retinal microvasculature in the superficial capillary plexus. Vessel density and perfusion density within the ETDRS 6-mm circle, 3-mm circle and 3-mm ring were compared between the patient groups. OCT images were collected with the Cirrus HD-OCT 5000 device with AngioPlex (Carl Zeiss Meditec).
Seventy eyes of 39 subjects with Alzheimer’s, 72 eyes of 37 subjects with mild cognitive impairment and 254 eyes of 133 healthy control participants were imaged and included in the analysis.
When compared with participants with mild cognitive impairment and controls, participants with Alzheimer’s exhibited significantly decreased 3-mm circle vessel density, 3-mm ring vessel density, 3-mm circle perfusion density and 3-mm ring perfusion density.
In addition, participants with Alzheimer’s exhibited significantly reduced 6-mm circle vessel density compared with participants with mild cognitive impairment, whereas participants with Alzheimer’s exhibited significantly reduced 6-mm circle perfusion density compared with control subjects.
Ganglion cell-inner plexiform layer thickness was significantly decreased in patients with Alzheimer’s in the inferior and inferonasal sectors compared with patients with mild cognitive impairment and in the entire, superonasal, inferior and inferonasal sectors compared with control subjects.
“At this time, OCT and OCT angiography cannot be used to diagnose Alzheimer’s. The goal ultimately would be to obtain multimodal images of the retina and optic nerve and create a suite of biomarkers used to predict the risk of Alzheimer’s disease (similar to getting a lipid panel and being able to determine one’s risk of heart disease), stratify the various stages of Alzheimer’s, and monitor the response to a novel treatment in the setting of a clinical trial,” Fekrat and Grewal said. – by Robert Linnehan
Disclosures: Fekrat reports no relevant financial disclosures. Grewal reports he receives financial support from Allergan and Alimera.