Ailin Song, Nicholas Johnson, Alexandria Ayala, Atalie C Thompson
{"title":"Optical Coherence Tomography in Patients with Alzheimer's Disease: What Can It Tell Us?","authors":"Ailin Song, Nicholas Johnson, Alexandria Ayala, Atalie C Thompson","doi":"10.2147/EB.S235238","DOIUrl":null,"url":null,"abstract":"<p><strong>Purpose: </strong>Although Alzheimer's disease (AD) is a leading cause of dementia worldwide, its clinical diagnosis remains a challenge. Optical coherence tomography (OCT) and OCT with angiography (OCTA) are non-invasive ophthalmic imaging tools with the potential to detect retinal structural and microvascular changes in patients with AD, which may serve as biomarkers for the disease. In this systematic review, we evaluate whether certain OCT and OCTA parameters are significantly associated with AD and mild cognitive impairment (MCI).</p><p><strong>Methods: </strong>PubMed database was searched using a combination of MeSH terms to identify studies for review. Studies were organized by participant diagnostic groups, type of imaging modality, and OCT/OCTA parameters of interest. Participant demographic data was also collected and baseline descriptive statistics were calculated for the included studies.</p><p><strong>Results: </strong>Seventy-one studies were included for review, representing a total of 6757 patients (2350 AD, 793 MCI, 2902 healthy controls (HC), and 841 others with a range of other neurodegenerative diagnoses). The mean baseline ages were 72.78±3.69, 71.52±2.88, 70.55±3.85 years for AD, MCI and HC groups, respectively. The majority of studies noted significant structural and functional decline in AD patients when compared to HC. Although analysis of MCI groups yielded more mixed results, a similar pattern of decline was often noted amongst patients with MCI relative to HC. OCT and OCTA measurements were also shown to correlate with established measures of AD such as neuropsychological testing or neuroimaging.</p><p><strong>Conclusion: </strong>OCT and OCTA show great potential as non-invasive technologies for the diagnosis of AD. However, further research is needed to determine whether there are AD-specific patterns of structural or microvascular change in the retina and optic nerve that distinguish AD from other neurodegenerative diseases. Development of sensitive and specific OCT/OCTA parameters will be necessary before they can be used to detect AD in clinical settings.</p>","PeriodicalId":51844,"journal":{"name":"Eye and Brain","volume":null,"pages":null},"PeriodicalIF":3.1000,"publicationDate":"2021-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/43/90/eb-13-1.PMC7802785.pdf","citationCount":"24","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Eye and Brain","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.2147/EB.S235238","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"2021/1/1 0:00:00","PubModel":"eCollection","JCR":"Q1","JCRName":"OPHTHALMOLOGY","Score":null,"Total":0}
引用次数: 24
Abstract
Purpose: Although Alzheimer's disease (AD) is a leading cause of dementia worldwide, its clinical diagnosis remains a challenge. Optical coherence tomography (OCT) and OCT with angiography (OCTA) are non-invasive ophthalmic imaging tools with the potential to detect retinal structural and microvascular changes in patients with AD, which may serve as biomarkers for the disease. In this systematic review, we evaluate whether certain OCT and OCTA parameters are significantly associated with AD and mild cognitive impairment (MCI).
Methods: PubMed database was searched using a combination of MeSH terms to identify studies for review. Studies were organized by participant diagnostic groups, type of imaging modality, and OCT/OCTA parameters of interest. Participant demographic data was also collected and baseline descriptive statistics were calculated for the included studies.
Results: Seventy-one studies were included for review, representing a total of 6757 patients (2350 AD, 793 MCI, 2902 healthy controls (HC), and 841 others with a range of other neurodegenerative diagnoses). The mean baseline ages were 72.78±3.69, 71.52±2.88, 70.55±3.85 years for AD, MCI and HC groups, respectively. The majority of studies noted significant structural and functional decline in AD patients when compared to HC. Although analysis of MCI groups yielded more mixed results, a similar pattern of decline was often noted amongst patients with MCI relative to HC. OCT and OCTA measurements were also shown to correlate with established measures of AD such as neuropsychological testing or neuroimaging.
Conclusion: OCT and OCTA show great potential as non-invasive technologies for the diagnosis of AD. However, further research is needed to determine whether there are AD-specific patterns of structural or microvascular change in the retina and optic nerve that distinguish AD from other neurodegenerative diseases. Development of sensitive and specific OCT/OCTA parameters will be necessary before they can be used to detect AD in clinical settings.
期刊介绍:
Eye and Brain is an international, peer-reviewed, open access journal focusing on basic research, clinical findings, and expert reviews in the field of visual science and neuro-ophthalmology. The journal’s unique focus is the link between two well-known visual centres, the eye and the brain, with an emphasis on the importance of such connections. All aspects of clinical and especially basic research on the visual system are addressed within the journal as well as significant future directions in vision research and therapeutic measures. This unique journal focuses on neurological aspects of vision – both physiological and pathological. The scope of the journal spans from the cornea to the associational visual cortex and all the visual centers in between. Topics range from basic biological mechanisms to therapeutic treatment, from simple organisms to humans, and utilizing techniques from molecular biology to behavior. The journal especially welcomes primary research articles or review papers that make the connection between the eye and the brain. Specific areas covered in the journal include: Physiology and pathophysiology of visual centers, Eye movement disorders and strabismus, Cellular, biochemical, and molecular features of the visual system, Structural and functional organization of the eye and of the visual cortex, Metabolic demands of the visual system, Diseases and disorders with neuro-ophthalmic manifestations, Clinical and experimental neuro-ophthalmology and visual system pathologies, Epidemiological studies.