A prospective case controlled study of 32 participants looked at the relationship of retinal blood ﬂow and vessel density to early onset Alzheimer disease (AD) and mild cognitive impairment.1
Patients with early onset AD and mild cognitive impairment were matched 1:1 with a control group. Evaluation of retinal blood ﬂow and vessel density was done with optical coherence tomography angiography.
Patients with early cognitive impairment associated with AD showed a signiﬁcant decline in parafoveal blood ﬂow and vascular density. The authors suggest these parameters when evaluated with optical coherence tomography angiography could have potential utility as an early biomarker in AD.
1. Zhang YS, Zhou N, Knoll BM. 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. 2019;14:e0214685.