10 Sep 20. Featured Paper

The application of optical coherence tomography angiography in cerebral small vessel disease, ischemic stroke, & dementia: a systematic review.

Link to paper in Frontiers Neurology.

Authors

Jun-Fang Zhang, Stewart Wiseman, Maria C. Valdés-Hernández, Fergus N. Doubal, Baljean Dhillon, Yun-Cheng Wu & Joanna M. Wardlaw

Abstract

Objective: To investigate the application of optical coherence tomography angiography (OCTA) in cerebral small vessel disease (SVD), ischemic stroke & dementia.

Methods: We conducted a systematic search in MEDLINE (from inception) & EMBASE (from 1980) to end 2019 for human studies that measured retinal parameters in cerebral SVD, ischemic stroke, & dementia using OCTA.

Results: Fourteen articles (n = 989) provided relevant data.

Ten studies included patients with Alzheimer disease (AD) & mild cognitive impairment (n = 679), two investigated pre-symptomatic AD participants (n = 154), & two investigated monogenic SVD patients with cerebral autosomal dominant arteriopathy with subcortical infarcts & leukoencephalopathy (n = 32) & Fabry disease (n = 124).

Methods to reduce bias & 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, & vessel density (VD) in AD, presymptomatic AD, & SVD patients.

Two (n = 160) of three studies (n = 192) showed association between decreased VD & 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 & different stages of AD, but data are limited & partly confounded by methodological differences.

Larger studies with risk factors adjustment & more consistent OCTA methods are needed to fully exploit this technology.

Keywords

• Alzheimer's disease

• Cerebral small vessel disease

• Dementia

• Ischemic stroke

• Optical coherence tomography angiography

• Retinal vasculature