The Application of Optical Coherence Tomography Angiography in Cerebral Small Vessel Disease, Ischemic Stroke, and Dementia: A Systematic Review

Abstract

Objective: To investigate the application of optical coherence tomography angiography (OCTA) in cerebral small vessel disease (SVD), ischemic stroke and dementia. Methods: We conducted a systematic search in MEDLINE (from inception) and EMBASE (from 1980) to end 2019 for human studies that measured retinal parameters in cerebral SVD, ischemic stroke, and dementia using OCTA. Results: Fourteen articles ( n = 989) provided relevant data. Ten studies included patients with Alzheimer disease (AD) and mild cognitive impairment ( n = 679), two investigated pre-symptomatic AD participants ( n = 154), and two investigated monogenic SVD patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy ( n = 32) and Fabry disease ( n = 124). Methods to reduce bias and risk factor adjustment were poorly reported. Substantial methodological variations between studies precluded a formal meta-analysis. Quantitative measurements revealed significant yet inconclusive changes in foveal avascular zone, perfusion density, and vessel density (VD) in AD, presymptomatic AD, and SVD patients. Two ( n = 160) of three studies ( n = 192) showed association between decreased VD and increased white matter hyperintensities. In three ( n = 297) of seven studies ( n = 563), better cognitive function was associated with increased VD. One study ( n = 52) suggested increased VD was associated with increased ganglion cell–inner plexiform layer thickness in AD yet with no covariate adjustment. Conclusions: Changes in retinal microvasculature identified using OCTA are associated with monogenic SVD and different stages of AD, but data are limited and partly confounded by methodological differences. Larger studies with risk factors adjustment and more consistent OCTA methods are needed to fully exploit this technology. PROSPERO registration number: CRD42020166929.

Involvement of cerebrovascular abnormalities in the pathogenesis and progression of Alzheimer’s disease: an adrenergic approach

“…Moreover, cAMP/AC independent mechanisms have also been found to be involved in the α2-AR-mediated vasoconstriction. For example, α2-AR can induce the vasoconstriction in the porcine palmar lateral vein via the activation of ERK-dependent signaling pathway and Src tyrosine kinases [ 75 ]. Interestingly, compared to nondemented, low pathology control subjects, AD patients showed a significant increase of α2A-AR activity.…”

“…Worth noting, one study in 2019, found that retinal vasculature did not discriminate AD patients from healthy controls [ 100 ]. However, much more recent experimental data were reported to support the utility of retinal vascular changes as potential marker of AD [ 75 , 101 – 104 ].…”

Choriocapillaris Changes Are Correlated With Disease Duration and MoCA Score in Early-Onset Dementia

“…It is responsible for the blood supply to the outer retina which includes the retinal pigment epithelium (RPE) and photoreceptors, and some portions of the inner retina (McLeod and Lutty, 1994). OCTA has been reported to be a convenient and invasive method to screen and monitor dementia development (Zhang et al, 2020). Our current study used an in-built software in the OCTA tool to assess the choriocapillaris blood flow in EOD patients which helps the reduction of projection artifacts.…”

The Retinal Vessel Density as a New Vascular Biomarker in Multisystem Involvement in Fabry Disease: An Optical Coherence Tomography Angiography Study

“…The retinal and cerebral small vessels share similar embryologic origins, anatomical features, and physiological properties; therefore, the retinal vessels may serve as a research model to detect subclinical cerebrovascular changes associated with FD [ 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 ].…”