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Carrero L, Antequera D, Municio C, Carro E. Circadian rhythm disruption and retinal dysfunction: a bidirectional link in Alzheimer's disease? Neural Regen Res 2024; 19:1967-1972. [PMID: 38227523 DOI: 10.4103/1673-5374.390962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 11/07/2023] [Indexed: 01/17/2024] Open
Abstract
Dysfunction in circadian rhythms is a common occurrence in patients with Alzheimer's disease. A predominant function of the retina is circadian synchronization, carrying information to the brain through the retinohypothalamic tract, which projects to the suprachiasmatic nucleus. Notably, Alzheimer's disease hallmarks, including amyloid-β, are present in the retinas of Alzheimer's disease patients, followed/associated by structural and functional disturbances. However, the mechanistic link between circadian dysfunction and the pathological changes affecting the retina in Alzheimer's disease is not fully understood, although some studies point to the possibility that retinal dysfunction could be considered an early pathological process that directly modulates the circadian rhythm.
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Affiliation(s)
- Laura Carrero
- Group of Neurodegenerative Diseases, Hospital Universitario 12 de Octubre Research Institute (imas12), Madrid, Spain; Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), ISCIII, Madrid, Spain
- PhD Program in Neuroscience, Autonoma de Madrid University, Madrid, Spain
| | - Desireé Antequera
- Neurobiology of Alzheimer's Disease Unit, Functional Unit for Research into Chronic Diseases, Instituto de Salud Carlos III, Madrid, Spain; Network Centre for Biomedical Research in Neurodegenerative Diseases (CIBERNED), ISCIII, Madrid, Spain
| | - Cristina Municio
- Group of Neurodegenerative Diseases, Hospital Universitario 12 de Octubre Research Institute (imas12), Madrid, Spain; Network Center for Biomedical Research in Neurodegenerative Diseases (CIBERNED), ISCIII, Madrid, Spain
| | - Eva Carro
- Neurobiology of Alzheimer's Disease Unit, Functional Unit for Research into Chronic Diseases, Instituto de Salud Carlos III, Madrid, Spain; Network Centre for Biomedical Research in Neurodegenerative Diseases (CIBERNED), ISCIII, Madrid, Spain
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2
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Shen Z, Zhang S, Yu W, Yue M, Hong C. Optical Coherence Tomography Angiography: Revolutionizing Clinical Diagnostics and Treatment in Central Nervous System Disease. Aging Dis 2024:AD.2024.0112. [PMID: 38300645 DOI: 10.14336/ad.2024.0112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 01/12/2024] [Indexed: 02/02/2024] Open
Abstract
Optical coherence tomography angiography (OCTA), as a new generation of non-invasive and efficient fundus imaging technology, can provide non-invasive assessment of vascular lesions in the retina and choroid. In terms of anatomy and development, the retina is referred to as an extension of the central nervous system (CNS). CNS diseases are closely related to changes in fundus structure and blood vessels, and direct visualization of fundus structure and blood vessels provides an effective "window" for CNS research. This has important practical significance for identifying the characteristic changes of various CNS diseases on OCTA in the future, and plays a key role in promoting early screening, diagnosis, and monitoring of disease progression in CNS diseases. This article reviews relevant fundus studies by comparing and summarizing the unique advantages and existing limitations of OCTA in various CNS disease patients, in order to demonstrate the clinical significance of OCTA in the diagnosis and treatment of CNS diseases.
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Affiliation(s)
- Zeqi Shen
- Postgraduate training base Alliance of Wenzhou Medical University (Affiliated People's Hospital), Hangzhou, Zhejiang, China
| | - Sheng Zhang
- Center for Rehabilitation Medicine, Department of Neurology, Zhejiang Provincial People's Hospital (Affiliated People's Hospital), Hangzhou Medical College, Hangzhou, Zhejiang, China
| | - Weitao Yu
- The Second School of Clinical Medicine, Hangzhou Normal University, Hangzhou, Zhejiang, China
| | - Mengmeng Yue
- Postgraduate training base Alliance of Wenzhou Medical University (Affiliated People's Hospital), Hangzhou, Zhejiang, China
| | - Chaoyang Hong
- Center for Rehabilitation Medicine, Department of Ophthalmology, Zhejiang Provincial People's Hospital (Affiliated People's Hospital), Hangzhou Medical College, Hangzhou, Zhejiang, China
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Carazo-Barrios L, Cabrera-Maestre A, Alba-Linero C, Gutiérrez-Bedmar M, Garzón-Maldonado FJ, Serrano V, de la Cruz-Cosme C, García-Casares N. Retinal Neurodegeneration Measured With Optical Coherence Tomography and Neuroimaging in Alzheimer Disease: A Systematic Review. J Neuroophthalmol 2023; 43:116-25. [PMID: 36255105 DOI: 10.1097/WNO.0000000000001673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Optical coherence tomography (OCT) has enabled several retinal alterations to be detected in patients with Alzheimer disease (AD), alterations that could be potential biomarkers. However, the relationship between the retina and other biomarkers of AD has been underresearched. We gathered and analyzed the literature about the relationship between retinal and cerebral alterations detected via neuroimaging in patients with AD, mild cognitive impairment (MCI), and preclinical AD. METHODS This systematic review followed the PRISMA Statement guidelines through the 27 items on its checklist. We searched in PubMed, BVS, Scopus, and the Cochrane Library, using the keywords: Alzheimer's disease, optical coherence tomography, white matter, cortex, atrophy, cortical thickness, neuroimaging, magnetic resonance imaging, and positron emission tomography. We included articles that studied the retina in relation to neuroimaging in patients with AD, MCI, and preclinical AD. We excluded studies without OCT, without neuroimaging, clinical cases, opinion articles, systematic reviews, and animal studies. RESULTS Of a total of 35 articles found, 23 were finally included. Although mixed results were found, most of these corroborate the relationship between retinal and brain disorders. CONCLUSIONS More rigorous research is needed in the field, including homogenized, longitudinal, and prolonged follow-up studies, as well as studies that include all stages of AD. This will enable better understanding of the retina and its implications in AD, leading to the discovery of retinal biomarkers that reflect brain alterations in AD patients in an accessible and noninvasive manner.
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Moussa M, Falfoul Y, Nasri A, El Matri K, Kacem I, Mrabet S, Chebil A, Gharbi A, Gouider R, El Matri L. Optical coherence tomography and angiography in Alzheimer's disease and other cognitive disorders. Eur J Ophthalmol 2023:11206721221148952. [PMID: 36617984 DOI: 10.1177/11206721221148952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
AIMS The aims of this study were to analyze retinal and choroidal changes on optical coherence tomography (OCT) and OCT-Angiography (OCT-A) in Alzheimer's disease (AD) patients and compare them to other forms of major dementia. We also aimed to analyze the correlation between clinical severity of global cognitive deficiency assessed by the mini-mental state exam (MMSE) score and OCT/OCT-A parameters. METHODS Retrospective cross-sectional evaluative study of AD, and age-and gender-matched patients with other dementias. Fundus examination, OCT and OCT-A were compared. RESULTS Ninety-one eyes of AD patients and 53 eyes of patients with other dementias were included. Retinal deposits were found in 6.59% of AD cases. OCT highlighted the presence of hyperreflective deposits and localized areas of outer retina and ellipsoid zone disruption, respectively in 20.87% and 15.38% of AD cases. Hyperreflective foci were noted within inner retinal layers in 4.39% of AD cases. Quantitative analysis revealed a thicker nasal retinal nerve fiber layer (p = 0.001) and ganglion cell complex in superior (p = 0.011) and temporal quadrants (p = 0.009) in eyes of AD patients, compared to other dementias. OCT-A showed a significantly higher fractal dimension of both superficial and deep capillary plexus (p = 0.005), with lower choriocapillaris density (p = 0.003) in AD patients. CONCLUSIONS Structural OCT could highlight the presence of hyperreflective deposits in AD, probably reflecting beta-amyloid deposits, associated to outer retinal disruptions. Quantitative OCT analysis showed structural differences between AD patients and other dementias, and combined OCT-A could identify microvascular changes in AD patients representing new potential differential diagnosis criteria.
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Affiliation(s)
- Mohamed Moussa
- Department of Ophthalmology B, 383447Hedi Raies Institute of Ophthalmology, Tunis, Tunisia
- Faculty of Medicine of Tunis, 37964University of Tunis El Manar, Tunis, Tunisia
| | - Yousra Falfoul
- Department of Ophthalmology B, 383447Hedi Raies Institute of Ophthalmology, Tunis, Tunisia
- Faculty of Medicine of Tunis, 37964University of Tunis El Manar, Tunis, Tunisia
| | - Amina Nasri
- Faculty of Medicine of Tunis, 37964University of Tunis El Manar, Tunis, Tunisia
- Department of Neurology, LR18SP03, Clinical Investigation Center "Neurosciences and Mental Health", Razi University Hospital, Tunis, Manouba, Tunisia
| | - Khaled El Matri
- Department of Ophthalmology B, 383447Hedi Raies Institute of Ophthalmology, Tunis, Tunisia
- Faculty of Medicine of Tunis, 37964University of Tunis El Manar, Tunis, Tunisia
| | - Imen Kacem
- Faculty of Medicine of Tunis, 37964University of Tunis El Manar, Tunis, Tunisia
- Department of Neurology, LR18SP03, Clinical Investigation Center "Neurosciences and Mental Health", Razi University Hospital, Tunis, Manouba, Tunisia
| | - Saloua Mrabet
- Faculty of Medicine of Tunis, 37964University of Tunis El Manar, Tunis, Tunisia
- Department of Neurology, LR18SP03, Clinical Investigation Center "Neurosciences and Mental Health", Razi University Hospital, Tunis, Manouba, Tunisia
| | - Ahmed Chebil
- Department of Ophthalmology B, 383447Hedi Raies Institute of Ophthalmology, Tunis, Tunisia
- Faculty of Medicine of Tunis, 37964University of Tunis El Manar, Tunis, Tunisia
| | - Alya Gharbi
- Faculty of Medicine of Tunis, 37964University of Tunis El Manar, Tunis, Tunisia
- Department of Neurology, LR18SP03, Clinical Investigation Center "Neurosciences and Mental Health", Razi University Hospital, Tunis, Manouba, Tunisia
| | - Riadh Gouider
- Faculty of Medicine of Tunis, 37964University of Tunis El Manar, Tunis, Tunisia
- Department of Neurology, LR18SP03, Clinical Investigation Center "Neurosciences and Mental Health", Razi University Hospital, Tunis, Manouba, Tunisia
| | - Leila El Matri
- Department of Ophthalmology B, 383447Hedi Raies Institute of Ophthalmology, Tunis, Tunisia
- Faculty of Medicine of Tunis, 37964University of Tunis El Manar, Tunis, Tunisia
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Abstract
Recent advances in retinal imaging pathophysiology have shown a new function for biomarkers in Alzheimer's disease diagnosis and prognosis. The significant improvements in Optical coherence tomography (OCT) retinal imaging have led to significant clinical translation, particularly in Alzheimer's disease detection. This systematic review will provide a comprehensive overview of retinal imaging in clinical applications, with a special focus on biomarker analysis for use in Alzheimer's disease detection. Articles on OCT retinal imaging in Alzheimer's disease diagnosis were identified in PubMed, Google Scholar, IEEE Xplore, and Research Gate databases until March 2021. Those studies using simultaneous retinal imaging acquisition were chosen, while those using sequential techniques were rejected. "Alzheimer's disease" and "Dementia" were searched alone and in combination with "OCT" and "retinal imaging". Approximately 1000 publications were searched, and after deleting duplicate articles, 145 relevant studies focused on the diagnosis of Alzheimer's disease utilizing retinal imaging were chosen for study. OCT has recently been demonstrated to be a valuable technique in clinical practice as according to this survey, 57% of the researchers employed optical coherence tomography, 19% used ocular fundus imaging, 13% used scanning laser ophthalmoscopy, and 11% have used multimodal imaging to diagnose Alzheimer disease. Retinal imaging has become an important diagnostic technique for Alzheimer's disease. Given the scarcity of available literature, it is clear that future prospective trials involving larger and more homogeneous groups are necessary, and the work can be expanded by evaluating its significance utilizing a machine-learning platform rather than simply using statistical methodologies.
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Affiliation(s)
- Richa Vij
- School of Computer Science & Engineering, Shri Mata Vaishno Devi University, Katra, Jammu and Kashmir, 182320, India
| | - Sakshi Arora
- School of Computer Science & Engineering, Shri Mata Vaishno Devi University, Katra, Jammu and Kashmir, 182320, India.
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Yeh TC, Kuo CT, Chou YB. Retinal Microvascular Changes in Mild Cognitive Impairment and Alzheimer's Disease: A Systematic Review, Meta-Analysis, and Meta-Regression. Front Aging Neurosci 2022; 14:860759. [PMID: 35572135 PMCID: PMC9096234 DOI: 10.3389/fnagi.2022.860759] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 03/14/2022] [Indexed: 01/03/2023] Open
Abstract
Background The remarkable increase in prevalence and significant morbidity of neurodegenerative diseases pose a tremendous burden for the health care system. Changes in retinal microvasculature metrics associated with Alzheimer's disease (AD) and mild cognitive impairment (MCI) may provide opportunities for early diagnosis and intervention. However, the role of retinal vascular biomarkers remains controversial. We aim to perform a systematic review, meta-analysis and meta-regression to evaluate the comprehensive retinal microvasculature changes in patients with AD and MCI. Methods We conducted a literature search on PubMed, MEDLINE, and EMBASE to identify studies published before May 2021 which assessed the measurements of optical coherence tomography angiography (OCTA) between AD, MCI with healthy control eyes, including foveal avascular zone (FAZ), vessel density (VD) of peripapillary, superficial and deep capillary plexus, and choroidal thickness using a random-effect model. We also performed meta-regression and subgroup analysis and assessed heterogeneity and publication bias to evaluate potential sources of bias. Results Compared with control eyes, VD of superficial capillary plexus was significantly lower in AD [standardized mean difference (SMD): −0.48; 95% CI (−0.70 to −0.27); p = 0.04] and MCI eyes [SMD: −0.42; 95% CI (−0.81 to −0.03); p = 0.03], as well as reduced VD of deep capillary plexus [SMD: −1.19; 95% CI (−2.00 to −0.38]; p < 0.001], [SMD: −0.53; 95% CI (−0.85 to −0.22); p < 0.001]. FAZ was significantly enlarged in AD eyes [SMD: 0.54; 95% CI (0.09 to 0.99); p = 0.02]. The meta-regression analysis showed that the OCTA machine type and macular scan size significantly influenced the variation of VD and FAZ between AD and control eyes (p < 0.05). Conclusion Our results highlight the potential of OCTA as a biomarker to detect early microvasculature deficits in AD and MCI. Notably, the macular scan size and different OCTA machine type could explain the heterogeneity observed in literatures. This information might be useful for future longitudinal study design to evaluate the role of OCTA in monitoring disease progression and treatment efficacy.
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Affiliation(s)
- Tsai-Chu Yeh
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan
- School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Chun-Tung Kuo
- Institute of Health Behaviors and Community Sciences, College of Public Health, National Taiwan University, Taipei, Taiwan
- School of Public Health, National Defense Medical Center, Taipei, Taiwan
| | - Yu-Bai Chou
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan
- School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
- *Correspondence: Yu-Bai Chou
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Klyucherev TO, Olszewski P, Shalimova AA, Chubarev VN, Tarasov VV, Attwood MM, Syvänen S, Schiöth HB. Advances in the development of new biomarkers for Alzheimer's disease. Transl Neurodegener 2022; 11:25. [PMID: 35449079 PMCID: PMC9027827 DOI: 10.1186/s40035-022-00296-z] [Citation(s) in RCA: 51] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 03/28/2022] [Indexed: 12/16/2022] Open
Abstract
Alzheimer's disease (AD) is a complex, heterogeneous, progressive disease and is the most common type of neurodegenerative dementia. The prevalence of AD is expected to increase as the population ages, placing an additional burden on national healthcare systems. There is a large need for new diagnostic tests that can detect AD at an early stage with high specificity at relatively low cost. The development of modern analytical diagnostic tools has made it possible to determine several biomarkers of AD with high specificity, including pathogenic proteins, markers of synaptic dysfunction, and markers of inflammation in the blood. There is a considerable potential in using microRNA (miRNA) as markers of AD, and diagnostic studies based on miRNA panels suggest that AD could potentially be determined with high accuracy for individual patients. Studies of the retina with improved methods of visualization of the fundus are also showing promising results for the potential diagnosis of the disease. This review focuses on the recent developments of blood, plasma, and ocular biomarkers for the diagnosis of AD.
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Affiliation(s)
- Timofey O Klyucherev
- Department of Neuroscience, Functional Pharmacology, University of Uppsala, Uppsala, Sweden.,Department of Pharmacology, Institute of Pharmacy, I. M. Sechenov First Moscow State Medical University, Moscow, Russia
| | - Pawel Olszewski
- Department of Neuroscience, Functional Pharmacology, University of Uppsala, Uppsala, Sweden
| | - Alena A Shalimova
- Department of Neuroscience, Functional Pharmacology, University of Uppsala, Uppsala, Sweden.,Department of Pharmacology, Institute of Pharmacy, I. M. Sechenov First Moscow State Medical University, Moscow, Russia
| | - Vladimir N Chubarev
- Institute of Translational Medicine and Biotechnology, I. M. Sechenov First Moscow State Medical University, Moscow, Russia
| | - Vadim V Tarasov
- Department of Pharmacology, Institute of Pharmacy, I. M. Sechenov First Moscow State Medical University, Moscow, Russia.,Institute of Translational Medicine and Biotechnology, I. M. Sechenov First Moscow State Medical University, Moscow, Russia
| | - Misty M Attwood
- Department of Neuroscience, Functional Pharmacology, University of Uppsala, Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Rudbeck Laboratory, Uppsala University, Uppsala, Sweden
| | - Helgi B Schiöth
- Department of Neuroscience, Functional Pharmacology, University of Uppsala, Uppsala, Sweden.
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Shi H, Koronyo Y, Rentsendorj A, Fuchs DT, Sheyn J, Black KL, Mirzaei N, Koronyo-Hamaoui M. Retinal Vasculopathy in Alzheimer's Disease. Front Neurosci 2021; 15:731614. [PMID: 34630020 PMCID: PMC8493243 DOI: 10.3389/fnins.2021.731614] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Accepted: 08/26/2021] [Indexed: 12/12/2022] Open
Abstract
The retina has been increasingly investigated as a site of Alzheimer’s disease (AD) manifestation for over a decade. Early reports documented degeneration of retinal ganglion cells and their axonal projections. Our group provided the first evidence of the key pathological hallmarks of AD, amyloid β-protein (Aβ) plaques including vascular Aβ deposits, in the retina of AD and mild cognitively impaired (MCI) patients. Subsequent studies validated these findings and further identified electroretinography and vision deficits, retinal (p)tau and inflammation, intracellular Aβ accumulation, and retinal ganglion cell-subtype degeneration surrounding Aβ plaques in these patients. Our data suggest that the brain and retina follow a similar trajectory during AD progression, probably due to their common embryonic origin and anatomical proximity. However, the retina is the only CNS organ feasible for direct, repeated, and non-invasive ophthalmic examination with ultra-high spatial resolution and sensitivity. Neurovascular unit integrity is key to maintaining normal CNS function and cerebral vascular abnormalities are increasingly recognized as early and pivotal factors driving cognitive impairment in AD. Likewise, retinal vascular abnormalities such as changes in vessel density and fractal dimensions, blood flow, foveal avascular zone, curvature tortuosity, and arteriole-to-venule ratio were described in AD patients including early-stage cases. A rapidly growing number of reports have suggested that cerebral and retinal vasculopathy are tightly associated with cognitive deficits in AD patients and animal models. Importantly, we recently identified early and progressive deficiency in retinal vascular platelet-derived growth factor receptor-β (PDGFRβ) expression and pericyte loss that were associated with retinal vascular amyloidosis and cerebral amyloid angiopathy in MCI and AD patients. Other studies utilizing optical coherence tomography (OCT), retinal amyloid-fluorescence imaging and retinal hyperspectral imaging have made significant progress in visualizing and quantifying AD pathology through the retina. With new advances in OCT angiography, OCT leakage, scanning laser microscopy, fluorescein angiography and adaptive optics imaging, future studies focusing on retinal vascular AD pathologies could transform non-invasive pre-clinical AD diagnosis and monitoring.
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Affiliation(s)
- Haoshen Shi
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Yosef Koronyo
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Altan Rentsendorj
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Dieu-Trang Fuchs
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Julia Sheyn
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Keith L Black
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Nazanin Mirzaei
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Maya Koronyo-Hamaoui
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States.,Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, United States
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9
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Csincsik L, Quinn N, Yong KXX, Crutch SJ, Peto T, Lengyel I. Retinal phenotyping of variants of Alzheimer's disease using ultra-widefield retinal images. Alzheimers Dement (Amst) 2021; 13:e12232. [PMID: 34458553 PMCID: PMC8377778 DOI: 10.1002/dad2.12232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 06/25/2021] [Accepted: 07/01/2021] [Indexed: 11/19/2022]
Abstract
BACKGROUND Posterior cortical atrophy (PCA) is the most common atypical variant of Alzheimer's disease (AD). Changes associated with PCA in the brain affect the visual cortex, but little is known about retinal changes in PCA. In this study, we explored retinal phenotypic variations in typical AD (tAD) and PCA. METHODS Retinal phenotyping was carried out on ultra-widefield (UWF) images of 69 control, 24 tAD, and 25 PCA participants. RESULTS Individuals with tAD (odds ratio [OR] = 2.76 [confidence interval (CI):1.24 to 6.10], P = .012) and PCA (OR = 3.40 [CI:1.25 to 9.22], P = .016) were more likely phenotyped as hard drusen. tAD (OR = 0.34 [CI:0.12 to 0.92], P = .035) were less likely to have soft drusen compared to control. Almost 3-fold increase in reticular pseudodrusen formation in tAD (OR = 2.93 [CI:1.10 to 7.76], P = .030) compared to control was estimated. DISCUSSION Studying the peripheral retina may contribute to a better understanding of differences in retinal phenotypes of different AD variants.
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Affiliation(s)
- Lajos Csincsik
- Wellcome‐Wolfson Institute for Experimental MedicineQueen's University BelfastBelfastUK
| | - Nicola Quinn
- Centre for Public HealthQueen's University BelfastBelfastUK
| | - Keir X. X. Yong
- Dementia Research CentreUCL Queen Square Institute of NeurologyUniversity College LondonLondonUK
| | - Sebastian J. Crutch
- Dementia Research CentreUCL Queen Square Institute of NeurologyUniversity College LondonLondonUK
| | - Tunde Peto
- Centre for Public HealthQueen's University BelfastBelfastUK
| | - Imre Lengyel
- Wellcome‐Wolfson Institute for Experimental MedicineQueen's University BelfastBelfastUK
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10
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Liu K, Li J, Raghunathan R, Zhao H, Li X, Wong STC. The Progress of Label-Free Optical Imaging in Alzheimer's Disease Screening and Diagnosis. Front Aging Neurosci 2021; 13:699024. [PMID: 34366828 PMCID: PMC8341907 DOI: 10.3389/fnagi.2021.699024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 07/02/2021] [Indexed: 01/13/2023] Open
Abstract
As the major neurodegenerative disease of dementia, Alzheimer's disease (AD) has caused an enormous social and economic burden on society. Currently, AD has neither clear pathogenesis nor effective treatments. Positron emission tomography (PET) and magnetic resonance imaging (MRI) have been verified as potential tools for diagnosing and monitoring Alzheimer's disease. However, the high costs, low spatial resolution, and long acquisition time limit their broad clinical utilization. The gold standard of AD diagnosis routinely used in research is imaging AD biomarkers with dyes or other reagents, which are unsuitable for in vivo studies owing to their potential toxicity and prolonged and costly process of the U.S. Food and Drug Administration (FDA) approval for human use. Furthermore, these exogenous reagents might bring unwarranted interference to mechanistic studies, causing unreliable results. Several label-free optical imaging techniques, such as infrared spectroscopic imaging (IRSI), Raman spectroscopic imaging (RSI), optical coherence tomography (OCT), autofluorescence imaging (AFI), optical harmonic generation imaging (OHGI), etc., have been developed to circumvent this issue and made it possible to offer an accurate and detailed analysis of AD biomarkers. In this review, we present the emerging label-free optical imaging techniques and their applications in AD, along with their potential and challenges in AD diagnosis.
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Affiliation(s)
- Kai Liu
- Translational Biophotonics Laboratory, Systems Medicine and Bioengineering Department, Houston Methodist Cancer Center, Houston, TX, United States
- Department of Gastrointestinal Surgery, The Third Xiangya Hospital of Central South University, Changsha, China
| | - Jiasong Li
- Translational Biophotonics Laboratory, Systems Medicine and Bioengineering Department, Houston Methodist Cancer Center, Houston, TX, United States
- T. T. and W. F. Chao Center for BRAIN, Houston Methodist Hospital, Houston, TX, United States
| | - Raksha Raghunathan
- Translational Biophotonics Laboratory, Systems Medicine and Bioengineering Department, Houston Methodist Cancer Center, Houston, TX, United States
- T. T. and W. F. Chao Center for BRAIN, Houston Methodist Hospital, Houston, TX, United States
| | - Hong Zhao
- Translational Biophotonics Laboratory, Systems Medicine and Bioengineering Department, Houston Methodist Cancer Center, Houston, TX, United States
| | - Xuping Li
- T. T. and W. F. Chao Center for BRAIN, Houston Methodist Hospital, Houston, TX, United States
| | - Stephen T. C. Wong
- Translational Biophotonics Laboratory, Systems Medicine and Bioengineering Department, Houston Methodist Cancer Center, Houston, TX, United States
- T. T. and W. F. Chao Center for BRAIN, Houston Methodist Hospital, Houston, TX, United States
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11
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López-Cuenca I, de Hoz R, Alcántara-Rey C, Salobrar-García E, Elvira-Hurtado L, Fernández-Albarral JA, Barabash A, Ramírez-Toraño F, de Frutos-Lucas J, Salazar JJ, Ramírez AI, Ramírez JM. Foveal Avascular Zone and Choroidal Thickness Are Decreased in Subjects with Hard Drusen and without High Genetic Risk of Developing Alzheimer's Disease. Biomedicines 2021; 9:638. [PMID: 34199664 DOI: 10.3390/biomedicines9060638] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/01/2021] [Accepted: 06/01/2021] [Indexed: 01/08/2023] Open
Abstract
A family history (FH+) of Alzheimer’s disease (AD) and ɛ4 allele of the ApoE gene are the main genetic risk factors for developing AD, whereas ɛ4 allele plays a protective role in age-related macular degeneration. Ocular vascular changes have been reported in both pathologies. We analyzed the choroidal thickness using optical coherence tomography (OCT) and the foveal avascular zone (FAZ) using OCT-angiography and compared the results with ApoE gene expression, AD FH+, and the presence or absence of hard drusen (HD) in 184 cognitively healthy subjects. Choroidal thickness was statistically significantly different in the (FH−, ɛ4−, HD+) group compared with (i) both the (FH−, ɛ4−, HD−) and the (FH+, ɛ4+, HD+) groups in the superior and inferior points at 1500 μm, and (ii) the (FH+, ɛ4−, HD+) group in the superior point at 1500 μm. There were statistically significant differences in the superficial FAZ between the (FH+, ɛ4−, HD+) group and (i) the (FH+, ɛ4−, HD−) group and (ii) the (FH+, ɛ4+, HD−) group. In conclusion, ocular vascular changes are not yet evident in participants with a genetic risk of developing AD.
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12
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Fereshetian S, Agranat JS, Siegel N, Ness S, Stein TD, Subramanian ML. Protein and Imaging Biomarkers in the Eye for Early Detection of Alzheimer's Disease. J Alzheimers Dis Rep 2021; 5:375-387. [PMID: 34189409 PMCID: PMC8203283 DOI: 10.3233/adr-210283] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/26/2021] [Indexed: 12/28/2022] Open
Abstract
Alzheimer's disease (AD) is one of the most common causes of dementia worldwide. Although no formal curative therapy exists for the treatment of AD, considerable research has been performed to identify biomarkers for early detection of this disease, and thus improved subsequent management. Given that the eye can be examined and imaged non-invasively with relative ease, it has emerged as an exciting area of research for evidence of biomarkers and to aid in the early diagnosis of AD. This review explores the current understanding of both protein and retinal imaging biomarkers in the eye. Herein, primary findings in the literature regarding AD biomarkers associated with the lens, retina, and other ocular structures are reviewed.
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Affiliation(s)
- Shaunt Fereshetian
- Boston University School of Medicine, Department of Ophthalmology, Boston, MA, USA
| | - Joshua S. Agranat
- Boston University School of Medicine, Department of Ophthalmology, Boston, MA, USA
- Boston Medical Center, Boston, MA, USA
| | - Nicole Siegel
- Boston University School of Medicine, Department of Ophthalmology, Boston, MA, USA
- Boston Medical Center, Boston, MA, USA
| | - Steven Ness
- Boston University School of Medicine, Department of Ophthalmology, Boston, MA, USA
- Boston Medical Center, Boston, MA, USA
| | - Thor D. Stein
- Boston University Alzheimer’s Disease and CTE Center, Boston University School of Medicine, Boston, MA, USA
- Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston, MA, USA
- VA Boston Healthcare System, Boston, MA, USA
- Department of Veterans Affairs Medical Center, Bedford, MA, USA
| | - Manju L. Subramanian
- Boston University School of Medicine, Department of Ophthalmology, Boston, MA, USA
- Boston Medical Center, Boston, MA, USA
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13
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Srinivasan S, Efron N. Optical coherence tomography in the investigation of systemic neurologic disease. Clin Exp Optom 2021; 102:309-319. [DOI: 10.1111/cxo.12858] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 10/21/2018] [Accepted: 10/28/2018] [Indexed: 11/30/2022] Open
Affiliation(s)
- Sangeetha Srinivasan
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia,
| | - Nathan Efron
- Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia,
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14
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Zhang S, Kwapong WR, Yang T, Liu P, Tuo Q, Cheng Y, Li X, Liu M, Lei P, Wu B. Choriocapillaris Changes Are Correlated With Disease Duration and MoCA Score in Early-Onset Dementia. Front Aging Neurosci 2021; 13:656750. [PMID: 33927609 PMCID: PMC8076507 DOI: 10.3389/fnagi.2021.656750] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Accepted: 03/24/2021] [Indexed: 02/05/2023] Open
Abstract
Purpose: Imaging of the choroid may detect the microvascular changes associated with early-onset dementia (EOD) and may represent an indicator for detection of the disease. We aimed to analyze the in vivo choriocapillaris (CC) flow density in EOD patients using optical coherence tomography angiography (OCTA) and evaluate the association with its clinical measures. Methods: This cross-sectional study used the OCTA to image and analyze the choriocapillaris (CC) of 25 EOD patients and 20 healthy controls. Choriocapillaris flow density in the 3 mm area and 6 mm area was measured by an inbuilt algorithm in the OCT tool. Brain volume using magnetic resonance imaging and cognitive assessment was done and recorded. Results: Significantly reduced capillary flow density of the choriocapillaris was seen in EOD patients when compared to healthy controls in the 3.0 mm (P = 0.001) and 6.0 mm (P < 0.001) area respectively. Montreal Cognitive Assessment (MoCA) scores in EOD patients positively correlated with choriocapillaris flow density in the 3 mm area (Rho = 0.466, P = 0.021). Disease duration of EOD patients also negatively correlated with choriocapillaris density in the 3 mm area (Rho = -0.497, P = 0.008). Discussion: Our report suggests that choriocapillaris damage may be a potential indicator of early-onset dementia. Microvascular impairment may be involved in the early phase of dementia without aging playing a role in its impairment. Clinical Trial Registration: www.ClinicalTrials.gov, ChiCTR2000041386.
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Affiliation(s)
- Shuting Zhang
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, China
| | | | - Tang Yang
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, China
| | - Peng Liu
- Department of Emergency, West China Hospital, Sichuan University, Chengdu, China
| | - Qingzhang Tuo
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Yajun Cheng
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, China
| | - Xue Li
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, China
| | - Ming Liu
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, China
| | - Peng Lei
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, China.,State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Bo Wu
- Department of Neurology, West China Hospital, Sichuan University, Chengdu, China
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15
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Csincsik L, Nelson R, Walpert MJ, Peto T, Holland A, Lengyel I. Increased choroidal thickness in adults with Down syndrome. Alzheimers Dement (Amst) 2021; 13:e12170. [PMID: 33748396 PMCID: PMC7967920 DOI: 10.1002/dad2.12170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 02/01/2021] [Accepted: 02/08/2021] [Indexed: 02/06/2023]
Abstract
INTRODUCTION People with Down syndrome (DS) are particularly susceptible to Alzheimer's disease (AD) due to the triplication of the amyloid precursor protein (APP) gene. In this cross-sectional study, we hypothesized that choroidal thinning reported in sporadic AD (sAD) is mirrored in adults with DS. METHODS The posterior pole of the eye for 24 adults with DS and 16 age-matched controls (Ctrl) were imaged with optical coherence tomography. Choroidal thickness (ChT) was measured and analyzed in relation to cognitive status and cerebral amyloid beta (Aβ) load. RESULTS ChT was increased in people with DS (pwDS) compared to Ctrl. This increase was associated with gender differences and positively correlated with cerebral Aβ load in a small subset. There was no significant correlation detected between ChT and age or cognitive status. DISCUSSION In contrast to sAD this study found a significantly thicker choroid in pwDS. Whether these changes are related to Aβ pathology in DS needs further investigation.
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Affiliation(s)
- Lajos Csincsik
- Wellcome‐Wolfson Institute for Experimental MedicineQueen's University BelfastBelfastUK
| | - Rachel Nelson
- Wellcome‐Wolfson Institute for Experimental MedicineQueen's University BelfastBelfastUK
| | - Madeleine J. Walpert
- Department of PsychiatryUniversity of Cambridge, Cambridge Intellectual and Developmental Disabilities Research GroupCambridgeUK
| | - Tunde Peto
- Wellcome‐Wolfson Institute for Experimental MedicineQueen's University BelfastBelfastUK
| | - Anthony Holland
- Department of PsychiatryUniversity of Cambridge, Cambridge Intellectual and Developmental Disabilities Research GroupCambridgeUK
| | - Imre Lengyel
- Wellcome‐Wolfson Institute for Experimental MedicineQueen's University BelfastBelfastUK
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16
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Li M, Li R, Lyu JH, Chen JH, Wang W, Gao ML, Li WJ, De J, Mu HY, Pan WG, Mao PX, Ma X. Relationship Between Alzheimer's Disease and Retinal Choroidal Thickness: A Cross-Sectional Study. J Alzheimers Dis 2021; 80:407-419. [PMID: 33554907 DOI: 10.3233/jad-201142] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
BACKGROUND The choroid is involved directly or indirectly in many pathological conditions such as Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS). OBJECTIVE The objective of this study was to investigate the association between retinal choroidal properties and the pathology of AD by determining choroidal thickness, hippocampus volume, cognitive functions, and plasma BACE1 activity. METHODS In this cross-sectional study, 37 patients with AD and 34 age-matched controls were included. Retinal choroidal thickness was measured via enhanced depth imaging optical coherence tomography. Hippocampal volume was measured via 3.0T MRI. Cognitive functions were evaluated using the Mini-Mental State Examination (MMSE) and Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-Cog). Plasma BACE1 activity was analyzed using a fluorescence substrate-based plasma assay, and regression model were to analyze the data. RESULTS Retinal choroidal thickness was significantly thinner in the AD group than in the control group [(114.81±81.30) μm versus (233.79±38.29) μm, p < 0.05]. Multivariable regression analysis indicated that the ADAS-cog scores (β=-0.772, p = 0.000) and age (β=-0.176, p = 0.015) were independently associated with choroidal thickness. The logistic regression model revealed that the subfoveal choroidal thickness was a significant predictor for AD (OR = 0.984, 95% CI: 0.972-0.997). CONCLUSION There was a general tendency of choroid thinning as the cognitive function declined. Although choroidal thickness was not a potential indicator for early stage AD, it was valuable in monitoring AD progression.
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Affiliation(s)
- Mo Li
- Beijing Anding Hospital, Capital Medical University, Beijing, China.,Center for Cognitive Disorders, Beijing Geriatric Hospital, Beijing, China
| | - Rena Li
- Beijing Anding Hospital, Capital Medical University, Beijing, China.,Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
| | - Ji-Hui Lyu
- Center for Cognitive Disorders, Beijing Geriatric Hospital, Beijing, China.,Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
| | - Jian-Hua Chen
- Department of Ophthalmology, Beijing Geriatric Hospital, Beijing, China
| | - Wei Wang
- Department of Ophthalmology, Beijing Geriatric Hospital, Beijing, China
| | - Mao-Long Gao
- The Geriatric Institute for Clinic and Rehabilitation, Beijing Geriatric Hospital, Beijing, China
| | - Wen-Jie Li
- Center for Cognitive Disorders, Beijing Geriatric Hospital, Beijing, China
| | - Jie De
- Department of Radiology, Beijing Geriatric Hospital, Beijing, China
| | - Han-Yan Mu
- Center for Cognitive Disorders, Beijing Geriatric Hospital, Beijing, China
| | - Wei-Gang Pan
- Beijing Anding Hospital, Capital Medical University, Beijing, China
| | - Pei-Xian Mao
- Beijing Anding Hospital, Capital Medical University, Beijing, China
| | - Xin Ma
- Beijing Anding Hospital, Capital Medical University, Beijing, China.,Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
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17
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Salobrar-Garcia E, Méndez-Hernández C, Hoz R, Ramírez AI, López-Cuenca I, Fernández-Albarral JA, Rojas P, Wang S, García-Feijoo J, Gil P, Salazar JJ, Ramírez JM. Ocular Vascular Changes in Mild Alzheimer's Disease Patients: Foveal Avascular Zone, Choroidal Thickness, and ONH Hemoglobin Analysis. J Pers Med 2020; 10:E231. [PMID: 33203157 DOI: 10.3390/jpm10040231] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 11/04/2020] [Accepted: 11/13/2020] [Indexed: 12/17/2022] Open
Abstract
In Alzheimer’s disease (AD), vascular changes could be caused by amyloid beta (Aβ) aggregates replacing the contractile smooth musculature of the arteriole walls. These changes happen in the brain vascular network, but also in the eye, and are related to decreased vascular density and low blood flow. In patients with Alzheimer’s disease, thinning of the choroid and the retina has been shown. The aim of this prospective study was to assess the retinal and choroidal vascular systems, analyzing the choroidal thickness with optical coherence tomography (OCT), the foveal avascular zone (FAZ) with OCT-angiography (OCTA), and the optic nerve head (ONH) hemoglobin with the Laguna ONhE program, to evaluate which of the two ocular vascular systems shows earlier changes in mild AD patients. These patients, compared to controls, showed a significantly thinner choroid at all the analyzed points, with the exception of the temporal macula (at 1000 and 1500 µm from the fovea). On the other hand, the FAZ and ONH hemoglobin did not show significant differences. In conclusion, a thinner choroid was the main ocular vascular change observed in mild AD patients, while the retinal vessels were not yet affected. Therefore, choroidal thickness could be used an early biomarker in AD.
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18
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Ashok A, Singh N, Chaudhary S, Bellamkonda V, Kritikos AE, Wise AS, Rana N, McDonald D, Ayyagari R. Retinal Degeneration and Alzheimer's Disease: An Evolving Link. Int J Mol Sci 2020; 21:E7290. [PMID: 33023198 DOI: 10.3390/ijms21197290] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 09/15/2020] [Accepted: 09/25/2020] [Indexed: 12/13/2022] Open
Abstract
Age-related macular degeneration (AMD) and glaucoma are degenerative conditions of the retina and a significant cause of irreversible blindness in developed countries. Alzheimer’s disease (AD), the most common dementia of the elderly, is often associated with AMD and glaucoma. The cardinal features of AD include extracellular accumulation of amyloid β (Aβ) and intracellular deposits of hyper-phosphorylated tau (p-tau). Neuroinflammation and brain iron dyshomeostasis accompany Aβ and p-tau deposits and, together, lead to progressive neuronal death and dementia. The accumulation of Aβ and iron in drusen, the hallmark of AMD, and Aβ and p-tau in retinal ganglion cells (RGC), the main retinal cell type implicated in glaucoma, and accompanying inflammation suggest overlapping pathology. Visual abnormalities are prominent in AD and are believed to develop before cognitive decline. Some are caused by degeneration of the visual cortex, while others are due to RGC loss or AMD-associated retinal degeneration. Here, we review recent information on Aβ, p-tau, chronic inflammation, and iron dyshomeostasis as common pathogenic mechanisms linking the three degenerative conditions, and iron chelation as a common therapeutic option for these disorders. Additionally discussed is the role of prion protein, infamous for prion disorders, in Aβ-mediated toxicity and, paradoxically, in neuroprotection.
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19
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López-de-Eguileta A, Lage C, López-García S, Pozueta A, García-Martínez M, Kazimierczak M, Bravo M, de Arcocha-Torres M, Banzo I, Jimenez-Bonilla J, Cerveró A, Goikoetxea A, Rodríguez-Rodríguez E, Sánchez-Juan P, Casado A. Evaluation of choroidal thickness in prodromal Alzheimer's disease defined by amyloid PET. PLoS One 2020; 15:e0239484. [PMID: 32956392 DOI: 10.1371/journal.pone.0239484] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 09/07/2020] [Indexed: 12/27/2022] Open
Abstract
Objective To assess and compare the involvement of choroidal thickness (CT) in patients with mild cognitive impairment (MCI) and dementia due to Alzheimer’s disease (AD) defined by amyloid PET and healthy controls (HC). Methods Sixty-three eyes from 34 AD patients [12 eyes (19.0%) with dementia and 51 eyes (80.9%) with MCI], positive to 11C-labelled Pittsburgh Compound-B with positron emission tomography (11C-PiB PET/CT), and the same number of sex- and age-paired HC were recruited. All participants underwent enhanced depth imaging optical coherence tomography (EDI-OCT) assessing CT at 14 measurements from 2 B-scans. Paired Student t-test was used to compare CT measurements between MCI, dementia and sex- and age-paired HC. A univariate generalized estimating equations model (GEE) test was performed to compare MCI and dementia individually with all HC included. Results Compared with HC, eyes from patients with positive 11C-PiB PET/CT showed a significant CT thinning in 5 selected locations (in foveal thickness in vertical scan, in temporal scan at 1500μm, in superior scan at 500μm and in inferior scan at 1000μm and 1500μm, p = 0.020–0.045) whilst few significant CT reduction data was reported in MCI or dementia individually versus HC. However, the GEE test identified significant CT thinning in AD compared with all HC included (p = 0.015–0.046). Conclusions To our knowledge, the present study is the first measuring CT in eyes from MCI and dementia eyes positive to 11C-PiB PET/CT reporting a significant trend towards CT thinning in MCI patients which became more pronounced in dementia stage. We support further investigation involving larger and prospective OCT studies in AD population characterized with available biomarkers to describe whether choroidal vascular damage occurs specifically in prodromal stages of AD.
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20
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Sekeryapan Gediz B, Ozturk M, Kilinc Hekimsoy H, Yuksel EG, Ozdamar Erol Y. Choroidal Vascularity Index as a Potential Inflammatory Biomarker for Obsessive Compulsive Disorder. Ocul Immunol Inflamm 2020; 30:428-432. [DOI: 10.1080/09273948.2020.1800052] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Berrak Sekeryapan Gediz
- Ophthalmology Department, University of Health Sciences, Ulucanlar Eye Training and Research Hospital, Ankara, Turkey
| | - Mehmet Ozturk
- Psychiatry Department, University of Health Sciences, Ankara Training and Research Hospital, Ankara, Turkey
| | - Hilal Kilinc Hekimsoy
- Ophthalmology Department, University of Health Sciences, Ulucanlar Eye Training and Research Hospital, Ankara, Turkey
| | - Emine Gokcen Yuksel
- Ophthalmology Department, University of Health Sciences, Ulucanlar Eye Training and Research Hospital, Ankara, Turkey
| | - Yasemin Ozdamar Erol
- Ophthalmology Department, University of Health Sciences, Ulucanlar Eye Training and Research Hospital, Ankara, Turkey
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21
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Subramanian ML, Vig V, Chung J, Fiorello MG, Xia W, Zetterberg H, Blennow K, Zetterberg M, Shareef F, Siegel NH, Ness S, Jun GR, Stein TD. Neurofilament light chain in the vitreous humor of the eye. Alzheimers Res Ther 2020; 12:111. [PMID: 32943089 PMCID: PMC7500015 DOI: 10.1186/s13195-020-00677-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 09/01/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND Neurofilament light chain (NfL) is a promising biomarker of neurodegeneration in the cerebrospinal fluid and blood. This study investigated the presence of NfL in the vitreous humor and its associations with amyloid beta, tau, inflammatory cytokines and vascular proteins, apolipoprotein E (APOE) genotypes, Mini-Mental State Examination (MMSE) scores, systemic disease, and ophthalmic diseases. METHODS This is a single-site, prospective, cross-sectional cohort study. Undiluted vitreous fluid (0.5-1.0 mL) was aspirated during vitrectomy, and whole blood was drawn for APOE genotyping. NfL, amyloid beta (Aβ), total Tau (t-Tau), phosphorylated Tau (p-Tau181), inflammatory cytokines, chemokines, and vascular proteins in the vitreous were quantitatively measured by immunoassay. The main outcome measures were the detection of NfL levels in the vitreous humor and its associations with the aforementioned proteins. Linear regression was used to test the associations of NfL with other proteins, APOE genotypes, MMSE scores, and ophthalmic and systemic diseases after adjustment for age, sex, education level, and other eye diseases. RESULTS NfL was detected in all 77 vitreous samples. NfL was not found to be associated with ophthalmic conditions, APOE genotypes, MMSE scores, or systemic disease (p > 0.05). NfL levels were positively associated with increased vitreous levels of Aβ40 (p = 7.7 × 10-5), Aβ42 (p = 2.8 × 10-4), and t-tau (p = 5.5 × 10-7), but not with p-tau181 (p = 0.53). NfL also had significant associations with inflammatory cytokines such as interleukin-15 (IL-15, p = 5.3 × 10-4), IL-16 (p = 2.2 × 10-4), monocyte chemoattractant protein-1 (MCP1, p = 4.1 × 10-4), and vascular proteins such as vascular endothelial growth factor receptor-1 (VEGFR1, p = 2.9 × 10-6), Vegf-C (p = 8.6 × 10-6), vascular cell adhesion molecule-1 (VCAM-1, p = 5.0 × 10-4), Tie-2 (p = 6.3 × 10-4), and intracellular adhesion molecular-1 (ICAM-1, p = 1.6 × 10-4). CONCLUSION NfL is detectable in the vitreous humor of the eye and significantly associated with amyloid beta, t-tau, and select inflammatory and vascular proteins in the vitreous. Additionally, NfL was not associated with patients' clinical eye condition. Our results serve as a foundation for further investigation of NfL in the ocular fluids to inform us about the potential utility of its presence in the eye.
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Affiliation(s)
- Manju L Subramanian
- Department of Ophthalmology, Boston Medical Center, Boston University School of Medicine, 85 E Concord St. #8813, Boston, MA, 02118, USA.
| | - Viha Vig
- Department of Ophthalmology, Boston Medical Center, Boston University School of Medicine, 85 E Concord St. #8813, Boston, MA, 02118, USA
| | - Jaeyoon Chung
- Department of Medicine (Biomedical Genetics Section), Boston University School of Medicine, Boston, MA, USA
| | - Marissa G Fiorello
- Department of Ophthalmology, Boston Medical Center, Boston University School of Medicine, 85 E Concord St. #8813, Boston, MA, 02118, USA
| | - Weiming Xia
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA
- Geriatric Research Education and Clinical Center, Bedford Veterans Affairs Medical Center, Bedford, MA, USA
| | - Henrik Zetterberg
- Department of Psychiatry and Neurochemistry at Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
- Department of Neurodegenerative Diseases, UCL Institute of Neurology, London, UK
- UK Dementia Research Institute at UCL, London, UK
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry at Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
- Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Madeleine Zetterberg
- Department of Clinical Neuroscience at Institute of Neuroscience and Physiology, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
| | - Farah Shareef
- Department of Ophthalmology, University of Illinois at Chicago School of Medicine, Chicago, IL, USA
| | - Nicole H Siegel
- Department of Ophthalmology, Boston Medical Center, Boston University School of Medicine, 85 E Concord St. #8813, Boston, MA, 02118, USA
| | - Steven Ness
- Department of Ophthalmology, Boston Medical Center, Boston University School of Medicine, 85 E Concord St. #8813, Boston, MA, 02118, USA
| | - Gyungah R Jun
- Department of Medicine (Biomedical Genetics Section), Boston University School of Medicine, Boston, MA, USA
| | - Thor D Stein
- Boston University Alzheimer's Disease and CTE Center, Boston University School of Medicine, Boston, MA, USA
- Department of Pathology and Laboratory Medicine, Boston Medical Center, Boston University School of Medicine, Boston, MA, USA
- Department of Veterans Affairs Medical Center, VA Boston Healthcare System, Boston, MA, USA
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22
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Mirzaei N, Shi H, Oviatt M, Doustar J, Rentsendorj A, Fuchs DT, Sheyn J, Black KL, Koronyo Y, Koronyo-Hamaoui M. Alzheimer's Retinopathy: Seeing Disease in the Eyes. Front Neurosci 2020; 14:921. [PMID: 33041751 PMCID: PMC7523471 DOI: 10.3389/fnins.2020.00921] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 08/10/2020] [Indexed: 01/18/2023] Open
Abstract
The neurosensory retina emerges as a prominent site of Alzheimer's disease (AD) pathology. As a CNS extension of the brain, the neuro retina is easily accessible for noninvasive, high-resolution imaging. Studies have shown that along with cognitive decline, patients with mild cognitive impairment (MCI) and AD often suffer from visual impairments, abnormal electroretinogram patterns, and circadian rhythm disturbances that can, at least in part, be attributed to retinal damage. Over a decade ago, our group identified the main pathological hallmark of AD, amyloid β-protein (Aβ) plaques, in the retina of patients including early-stage clinical cases. Subsequent histological, biochemical and in vivo retinal imaging studies in animal models and in humans corroborated these findings and further revealed other signs of AD neuropathology in the retina. Among these signs, hyperphosphorylated tau, neuronal degeneration, retinal thinning, vascular abnormalities and gliosis were documented. Further, linear correlations between the severity of retinal and brain Aβ concentrations and plaque pathology were described. More recently, extensive retinal pericyte loss along with vascular platelet-derived growth factor receptor-β deficiency were discovered in postmortem retinas of MCI and AD patients. This progressive loss was closely associated with increased retinal vascular amyloidosis and predicted cerebral amyloid angiopathy scores. These studies brought excitement to the field of retinal exploration in AD. Indeed, many questions still remain open, such as queries related to the temporal progression of AD-related pathology in the retina compared to the brain, the relations between retinal and cerebral changes and whether retinal signs can predict cognitive decline. The extent to which AD affects the retina, including the susceptibility of certain topographical regions and cell types, is currently under intense investigation. Advances in retinal amyloid imaging, hyperspectral imaging, optical coherence tomography, and OCT-angiography encourage the use of such modalities to achieve more accurate, patient- and user-friendly, noninvasive detection and monitoring of AD. In this review, we summarize the current status in the field while addressing the many unknowns regarding Alzheimer's retinopathy.
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Affiliation(s)
- Nazanin Mirzaei
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Haoshen Shi
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Mia Oviatt
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Jonah Doustar
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Altan Rentsendorj
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Dieu-Trang Fuchs
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Julia Sheyn
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Keith L. Black
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Yosef Koronyo
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Maya Koronyo-Hamaoui
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA, United States
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, United States
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Gupta VB, Chitranshi N, den Haan J, Mirzaei M, You Y, Lim JK, Basavarajappa D, Godinez A, Di Angelantonio S, Sachdev P, Salekdeh GH, Bouwman F, Graham S, Gupta V. Retinal changes in Alzheimer's disease- integrated prospects of imaging, functional and molecular advances. Prog Retin Eye Res 2020; 82:100899. [PMID: 32890742 DOI: 10.1016/j.preteyeres.2020.100899] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 08/24/2020] [Accepted: 08/27/2020] [Indexed: 12/31/2022]
Abstract
Alzheimer's Disease (AD) is a devastating neurodegenerative disorder of the brain, clinically characterised by cognitive deficits that gradually worsen over time. There is, at present, no established cure, or disease-modifying treatments for AD. As life expectancy increases globally, the number of individuals suffering from the disease is projected to increase substantially. Cumulative evidence indicates that AD neuropathological process is initiated several years, if not decades, before clinical signs are evident in patients, and diagnosis made. While several imaging, cognitive, CSF and blood-based biomarkers have been proposed for the early detection of AD; their sensitivity and specificity in the symptomatic stages is highly variable and it is difficult to justify their use in even earlier, pre-clinical stages of the disease. Research has identified potentially measurable functional, structural, metabolic and vascular changes in the retina during early stages of AD. Retina offers a distinctively accessible insight into brain pathology and current and developing ophthalmic technologies have provided us with the possibility of detecting and characterising subtle, disease-related changes. Recent human and animal model studies have further provided mechanistic insights into the biochemical pathways that are altered in the retina in disease, including amyloid and tau deposition. This information coupled with advances in molecular imaging has allowed attempts to monitor biochemical changes and protein aggregation pathology in the retina in AD. This review summarises the existing knowledge that informs our understanding of the impact of AD on the retina and highlights some of the gaps that need to be addressed. Future research will integrate molecular imaging innovation with functional and structural changes to enhance our knowledge of the AD pathophysiological mechanisms and establish the utility of monitoring retinal changes as a potential biomarker for AD.
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Affiliation(s)
- Veer B Gupta
- School of Medicine, Deakin University, VIC, Australia
| | - Nitin Chitranshi
- Faculty of Medicine Health and Human Sciences, Macquarie University, North Ryde, NSW, 2109, Australia
| | - Jurre den Haan
- Department of Neurology, Alzheimer Center Amsterdam, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam UMC, the Netherlands
| | - Mehdi Mirzaei
- Faculty of Medicine Health and Human Sciences, Macquarie University, North Ryde, NSW, 2109, Australia
| | - Yuyi You
- Faculty of Medicine Health and Human Sciences, Macquarie University, North Ryde, NSW, 2109, Australia
| | - Jeremiah Kh Lim
- Optometry and Vision Science, College of Nursing and Health Sciences, Bedford Park, South Australia, 5042, Australia
| | - Devaraj Basavarajappa
- Faculty of Medicine Health and Human Sciences, Macquarie University, North Ryde, NSW, 2109, Australia
| | - Angela Godinez
- Faculty of Medicine Health and Human Sciences, Macquarie University, North Ryde, NSW, 2109, Australia
| | - Silvia Di Angelantonio
- Center for Life Nanoscience, Istituto Italiano di Tecnologia, Rome, Italy; Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Perminder Sachdev
- Centre for Healthy Brain and Ageing (CHeBA), School of Psychiatry, Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia; Neuropsychiatric Institute, Prince of Wales Hospital, Sydney, New South Wales, Australia
| | - Ghasem H Salekdeh
- Department of Molecular Systems Biology, Cell Science Research Center, Royan, Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
| | - Femke Bouwman
- Department of Neurology, Alzheimer Center Amsterdam, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam UMC, the Netherlands
| | - Stuart Graham
- Faculty of Medicine Health and Human Sciences, Macquarie University, North Ryde, NSW, 2109, Australia; Save Sight Institute, Sydney University, Sydney, NSW, 2000, Australia.
| | - Vivek Gupta
- Faculty of Medicine Health and Human Sciences, Macquarie University, North Ryde, NSW, 2109, Australia.
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24
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Chibhabha F, Yaqi Y, Li F. Retinal involvement in Alzheimer's disease (AD): evidence and current progress on the non-invasive diagnosis and monitoring of AD-related pathology using the eye. Rev Neurosci 2020; 31:/j/revneuro.ahead-of-print/revneuro-2019-0119/revneuro-2019-0119.xml. [PMID: 32804680 DOI: 10.1515/revneuro-2019-0119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Accepted: 06/04/2020] [Indexed: 12/22/2022]
Abstract
Alzheimer's disease (AD) is a common form of age-related dementia that mostly affects the aging population. Clinically, it is a disease characterized by impaired memory and progressive cognitive decline. Although the pathological hallmarks of AD have been traditionally described with a general confinement in the brain, recent studies have shown similar pathological changes in the retina, which is a developmental outgrowth of the forebrain. These AD-related neurodegenerative changes in the retina have been implicated to cause early visual problems in AD even before cognitive impairment becomes apparent. With recent advances in research, the commonly held view that AD-related cerebral pathology causes visual dysfunction through disruption of central visual pathways has been re-examined. Currently, several studies have already explored how AD manifests in the retina and the possibility of using the same retina as a window to non-invasively examine AD-related pathology in the brain. Non-invasive screening of AD through the retina has the potential to improve on early detection and management of the disease since the majority of AD cases are usually diagnosed very late. The purpose of this review is to provide evidence on the involvement of the retina in AD and to suggest a possible direction for future research into the non-invasive screening, diagnosis, and monitoring of AD using the retina.
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Affiliation(s)
- Fidelis Chibhabha
- Department of Anatomy and Neurobiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou510080,China
- Department of Anatomy, Faculty of Medicine, Midlands State University, P. Bag 9055, Senga, Gweru, Zimbabwe
- and Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080,China
| | - Yang Yaqi
- Department of Anatomy and Neurobiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou510080,China
- and Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080,China
| | - Feng Li
- Department of Anatomy and Neurobiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou510080,China
- and Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080,China
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25
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Wright LM, Stein TD, Jun G, Chung J, McConnell K, Fiorello M, Siegel N, Ness S, Xia W, Turner KL, Subramanian ML. Association of Cognitive Function with Amyloid-β and Tau Proteins in the Vitreous Humor. J Alzheimers Dis 2020; 68:1429-1438. [PMID: 30856114 DOI: 10.3233/jad-181104] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND The eye may serve as source for diagnostic testing for early detection of Alzheimer's disease (AD). Examination of amyloid-β (Aβ) and tau protein content in human vitreous and its correlation to neuro-cognition may improve ocular-based AD detection methods. OBJECTIVE To evaluate levels of Aβ and tau protein in human vitreous humor and investigate the clinical predictive role of these proteins as early diagnostic markers of AD. METHODS A prospective, single-center, multi-surgeon cohort study. Vitreous humor samples from 80 eyes were measured quantitatively for Aβ40-42, pTau, and tTau. Linear regression was used to test associations between AD biomarker levels, Mini-Mental State Exam (MMSE), and serum apolipoprotein E (APOE) allele status, with adjustment for age, sex, and education level of patients. RESULTS Lower MMSE scores were significantly associated with lower levels of vitreous Aβ40 (p = 0.015), Aβ42 (p = 0.0066), and tTau (p = 0.0085), and these biomarkers were not associated with any pre-existing eye conditions. Presence of the ɛ4 allele and the ɛ2 allele approached significance with reduced Aβ40 level (p = 0.053) and increased p-Tau level (p = 0.056), respectively. CONCLUSION Patients with poor cognitive function have significantly lower vitreous humor levels of AD-related biomarkers Aβ40, Aβ42, and tTau. These biomarkers do not correlate with underlying eye conditions, suggesting their specificity in association with cognitive change. This is the first study to our knowledge to correlate cognition with AD-related proteins in the vitreous humor. Results suggest ocular proteins may have a role for early dementia detection in individuals at risk for AD.
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Affiliation(s)
- Lauren M Wright
- Department of Ophthalmology, Boston University School of Medicine, Boston Medical Center, Boston, MA, USA
| | - Thor D Stein
- Department of Pathology and Laboratory Medicine, Boston University School of Medicine, Boston Medical Center, Boston, MA, USA.,Department of Veterans Affairs Medical Center, Bedford, MA, USA.,VA Boston Healthcare System, Boston, MA, USA.,Boston University Alzheimer's Disease and CTE Center, Boston University School of Medicine, Boston, MA, USA
| | - Gyungah Jun
- Department of Genetics, Boston University School of Medicine, Boston Medical Center, Boston, MA, USA.,Department of Epidemiology and Biostatistics, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Jaeyoon Chung
- Department of Genetics, Boston University School of Medicine, Boston Medical Center, Boston, MA, USA.,Department of Epidemiology and Biostatistics, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Kate McConnell
- Department of Ophthalmology, Boston University School of Medicine, Boston Medical Center, Boston, MA, USA
| | - Marissa Fiorello
- Department of Ophthalmology, Boston University School of Medicine, Boston Medical Center, Boston, MA, USA
| | - Nicole Siegel
- Department of Ophthalmology, Boston University School of Medicine, Boston Medical Center, Boston, MA, USA
| | - Steven Ness
- Department of Ophthalmology, Boston University School of Medicine, Boston Medical Center, Boston, MA, USA
| | - Weiming Xia
- Boston University Alzheimer's Disease and CTE Center, Boston University School of Medicine, Boston, MA, USA.,Department of Pharmacology and Experimental Therapeutics, Veterans Affairs Medical Center, Bedford, MA, USA
| | - Kelley L Turner
- Department of Ophthalmology, Boston University School of Medicine, Boston Medical Center, Boston, MA, USA
| | - Manju L Subramanian
- Department of Ophthalmology, Boston University School of Medicine, Boston Medical Center, Boston, MA, USA
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26
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DI Staso F, Ciancaglini M, Abdolrahimzadeh S, D'Apolito F, Scuderi G. Optical Coherence Tomography of Choroid in Common Neurological Diseases. In Vivo 2020; 33:1403-1409. [PMID: 31471385 DOI: 10.21873/invivo.11617] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 07/07/2019] [Accepted: 07/12/2019] [Indexed: 01/13/2023]
Abstract
The choroid is involved directly and indirectly in many pathological conditions such as age-related macular degeneration, myopia-related chorioretinal atrophy and central serous chorioretinopathy. Optical coherence tomography (OCT) has gradually become a fundamental part of modern resources in the hands of ophthalmologists. The enhanced depth imaging technique and swept-source OCT make a great contribution to conventional in vivo choroid assessment. This review focuses on the most common neurological conditions in which choroid assessment by OCT may provide help in early diagnosis and be used as an interdisciplinary follow-up tool. In order to avoid evaluation biases and misdiagnosis, the main and most common physiological and para-physiological conditions in which the choroid may show alterations are also reviewed.
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Affiliation(s)
- Federico DI Staso
- Ophthalmology Unit, NESMOS Department, St. Andrea Hospital, Sapienza University of Rome, Rome, Italy
| | - Marco Ciancaglini
- Eye Clinic, San Salvatore Hospital, University of L'Aquila, L'Aquila, Italy
| | - Solmaz Abdolrahimzadeh
- Ophthalmology Unit, NESMOS Department, St. Andrea Hospital, Sapienza University of Rome, Rome, Italy
| | - Fabian D'Apolito
- Ophthalmology Unit, NESMOS Department, St. Andrea Hospital, Sapienza University of Rome, Rome, Italy
| | - Gianluca Scuderi
- Ophthalmology Unit, NESMOS Department, St. Andrea Hospital, Sapienza University of Rome, Rome, Italy
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27
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Yap TE, Balendra SI, Almonte MT, Cordeiro MF. Retinal correlates of neurological disorders. Ther Adv Chronic Dis 2019; 10:2040622319882205. [PMID: 31832125 PMCID: PMC6887800 DOI: 10.1177/2040622319882205] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 09/20/2019] [Indexed: 12/11/2022] Open
Abstract
Considering the retina as an extension of the brain provides a platform from which to study diseases of the nervous system. Taking advantage of the clear optical media of the eye and ever-increasing resolution of modern imaging techniques, retinal morphology can now be visualized at a cellular level in vivo. This has provided a multitude of possible biomarkers and investigative surrogates that may be used to identify, monitor and study diseases until now limited to the brain. In many neurodegenerative conditions, early diagnosis is often very challenging due to the lack of tests with high sensitivity and specificity, but, once made, opens the door to patients accessing the correct treatment that can potentially improve functional outcomes. Using retinal biomarkers in vivo as an additional diagnostic tool may help overcome the need for invasive tests and histological specimens, and offers the opportunity to longitudinally monitor individuals over time. This review aims to summarise retinal biomarkers associated with a range of neurological conditions including Alzheimer’s disease (AD), Parkinson’s disease (PD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS) and prion diseases from a clinical perspective. By comparing their similarities and differences according to primary pathological processes, we hope to show how retinal correlates can aid clinical decisions, and accelerate the study of this rapidly developing area of research.
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Affiliation(s)
- Timothy E Yap
- The Western Eye Hospital, Imperial College Healthcare NHS Trust (ICHNT), London, UK
| | - Shiama I Balendra
- Glaucoma and Retinal Neurodegeneration Group, Department of Visual Neuroscience, UCL Institute of Ophthalmology, London, UK
| | - Melanie T Almonte
- The Imperial College Ophthalmic Research Group (ICORG), Imperial College London, UK
| | - M Francesca Cordeiro
- The Western Eye Hospital, Imperial College Healthcare NHS Trust (ICHNT), London, NW1 5QH, UK
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28
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Asanad S, Ross-Cisneros FN, Barron E, Nassisi M, Sultan W, Karanjia R, Sadun AA. The retinal choroid as an oculovascular biomarker for Alzheimer's dementia: A histopathological study in severe disease. Alzheimers Dement (Amst) 2019; 11:775-783. [PMID: 31737776 PMCID: PMC6849152 DOI: 10.1016/j.dadm.2019.08.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Introduction Previous in vivo optical coherence tomography studies have proposed the retinal choroid as a potential oculovascular biomarker for Alzheimer's disease (AD). However, the clinical use of the choroid as a purported surrogate marker remains poorly understood. We pursued a histopathological approach to assess choroidal thickness and vascular morphology in severe disease. Methods Human postmortem tissues from 8 patients with AD (mean age: 80.1 ± 12.7 years) and from 11 age-matched controls (mean age: 78.4 ± 16.57 years) were analyzed. Thickness, area, and vascularity of the retinal choroid and its sublayers were measured from the nasal and temporal quadrants of the superior retina. Results Nasally, the choroid was thinner in the patients with AD than in the controls (22% thickness reduction; P < .001), but to our surprise, the choroid was thicker in the patients with AD than in the controls (~60% increase; P < .03) within the macula, temporally. The choroidal area was also significantly greater in the patients with AD than in the controls (~60% increase; P < .03). Choroidal thickening in AD was strongly correlated with the stromal vessel number (R2 = 0.96, P < .001). Discussion We found significant differences in the retinal choroid by layer and by region, nasally and temporally with respect to the optic nerve. Intriguingly, the choroid was markedly thicker in the central macular region and was strongly associated with vessel number in the stromal vascular layer. These quantified histological findings in severe disease expand our understanding of vascular pathology in AD and suggest vascularity as a potential biomarker supplementary to thickness when evaluating the retinal choroid in AD.
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Affiliation(s)
- Samuel Asanad
- Doheny Eye Institute, Los Angeles, CA, USA.,Department of Ophthalmology, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, USA
| | | | | | | | | | - Rustum Karanjia
- Doheny Eye Institute, Los Angeles, CA, USA.,Department of Ophthalmology, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, USA.,Department of Ophthalmology, University of Ottawa, Ottawa, Ontario, Canada.,Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - Alfredo A Sadun
- Doheny Eye Institute, Los Angeles, CA, USA.,Department of Ophthalmology, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, USA
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29
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Cheng DL, Thompson L, Snyder PJ. A Potential Association Between Retinal Changes, Subjective Memory Impairment, and Anxiety in Older Adults at Risk for Alzheimer's Disease: A 27-Month Pilot Study. Front Aging Neurosci 2019; 11:288. [PMID: 31736739 PMCID: PMC6830450 DOI: 10.3389/fnagi.2019.00288] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 10/07/2019] [Indexed: 11/13/2022] Open
Abstract
Introduction The utility of subjective memory impairment (SMI) as a risk marker for preclinical Alzheimer's disease (AD) remains unclear; however, recent studies have identified a correlation between retinal biomarkers and onset of preclinical disease. This study examines the relationship between retinal biomarkers that have been associated with cerebral amyloid, an early hallmark of AD, and SMI scores in patients at risk for developing AD. Methods Forty-nine cognitively normal subjects were followed over 27 months and evaluated using a combination of neuropsychological, psychological, and retinal imaging instruments. Subjective memory testing was conducted using the memory assessment clinic questionnaire (MACQ) and Depression, Anxiety, and Stress Scales (DASS). Multivariate linear analysis was conducted using STATA software. Results Positive correlations were found between retinal nerve fiber layer (RNFL) volume and scores obtained from the MAC-Q at 27 months (MAC-Q_27), the DASS questionnaire for anxiety at 27 months (DASS-A_27), and the change in DASS-A over 27 months (dDASSA). There was also a significant positive correlation between these variables and the change in RNFL thickness over 27 months (dRNFL). MACQ_27, DASSA_27, and dDASS-A accounted for 35.7% of RFNL variance at 27 months and 21.5% of dRFNL variance. Discussion These findings suggest that worse subjective memory complaints and anxiety scores may be associated with one of the most commonly used structural anatomical retinal markers of early disease burden in AD. If so, these results lend support to SMI as a valid risk marker for later cognitive decline.
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Affiliation(s)
- Derrick L Cheng
- The Warren Alpert Medical School of Brown University, Providence, RI, United States
| | - Louisa Thompson
- Department of Neurology, Alpert Medical School, Brown University, Providence, RI, United States
| | - Peter J Snyder
- Department of Neurology, Alpert Medical School, Brown University, Providence, RI, United States.,The Interdisciplinary Neuroscience Program, University of Rhode Island, Kingston, RI, United States
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30
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Cabrera DeBuc D, Gaca-Wysocka M, Grzybowski A, Kanclerz P. Identification of Retinal Biomarkers in Alzheimer's Disease Using Optical Coherence Tomography: Recent Insights, Challenges, and Opportunities. J Clin Med 2019; 8:jcm8070996. [PMID: 31323964 PMCID: PMC6678943 DOI: 10.3390/jcm8070996] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Revised: 06/30/2019] [Accepted: 07/04/2019] [Indexed: 12/20/2022] Open
Abstract
This review will highlight recent insights into measuring retinal structure in Alzheimer’s disease (AD). A growing body of evidence indicates that disturbances in retinal blood flow and structure are related to cognitive function, which can severely impair vision. Optical coherence tomography (OCT) is an optical imaging technology that may allow researchers and physicians to gain deeper insights into retinal morphology and clarify the impact of AD on retinal health and function. Direct and noninvasive measurement of retinal morphology using OCT has provided useful diagnostic and therapeutic indications in several central nervous system (CNS) diseases, including AD, multiple sclerosis, and Parkinson disease. Despite several limitations, morphology assessment in the retinal layers is a significant advancement in the understanding of ocular diseases. Nevertheless, additional studies are required to validate the use of OCT in AD and its complications in the eye.
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Affiliation(s)
- Delia Cabrera DeBuc
- Bascom Palmer Eye Institute, Department of Ophthalmology, Miller School of Medicine, University of Miami, Miami, FL 33136, USA.
| | | | - Andrzej Grzybowski
- Department of Ophthalmology, University of Warmia and Mazury, 10-082 Olsztyn, Poland
- Institute for Research in Ophthalmology, Foundation for Ophthalmology Development, 60-554 Poznan, Poland
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31
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Casado A, López-de-Eguileta A, Gaitán J, Fonseca S, Gordo-Vega MA. Peripapillary and macular choroidal thickness before and after phenylephrine instillation. Eye (Lond) 2019; 33:1741-7. [PMID: 31164729 DOI: 10.1038/s41433-019-0478-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Revised: 04/17/2019] [Accepted: 05/01/2019] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVES We investigated the effects of topical phenylephrine 2.5% instillation on choroidal thickness (CT), peripapillary choroidal thickness (pCT) and retinal nerve fibre layer (RNFL). METHODS Healthy control patients underwent enhanced depth imaging (EDI) by spectral-domain optical coherence tomography (OCT) before and 30 min after phenylephrine instillation, using eye-tracking and follow-up software. Changes in 14 different locations of CT, 2 locations of pCT and RNFL were assessed. RESULTS The study included 119 eyes of 62 patients (19 males and 43 females), with a mean age of 59.8 ± 15.3 years (range: 26-88 years). Within 30 min after instillation, the mean subfoveal CT both in vertical and horizontal scan were significantly thinned (p = 0.005 and p = 0.018, respectively). In total, 1500, 1000 and 500 µm temporal CT measurements showed also a significant thinning (p = 0.021, p = 0.037 and p = 0.020, respectively), as well as 500 µm both superior (p = 0.045) and inferior (p = 0.009). 1500, 1000 and 500 µm nasal CT, and 1500 and 1000 µm CT superior and inferior measurements showed no significant thinning after phenylephrine instillation. pCT was significantly thinned after phenylephrine in both superior (p = 0.016) and inferior (p = 0.050) measurements. RNFL analysis did not significantly change after phenylephrine instillation (p = 0.209). CONCLUSIONS A significant thinning of CT and pCT occurred following phenylephrine instillation. Future studies analysing CT and pCT should detail if this mydriatic agent was used or not.
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32
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den Haan J, van de Kreeke JA, van Berckel BN, Barkhof F, Teunissen CE, Scheltens P, Verbraak FD, Bouwman FH. Is retinal vasculature a biomarker in amyloid proven Alzheimer's disease? Alzheimers Dement (Amst) 2019; 11:383-391. [PMID: 31193094 PMCID: PMC6517376 DOI: 10.1016/j.dadm.2019.03.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Introduction The retina is a potential source of noninvasive vascular biomarkers for Alzheimer's disease (AD). We assessed retinal microvasculature in well-characterized AD cases, taking ophthalmological confounders into account. Methods We included 48 amyloid-positive AD patients and 38 amyloid-negative cognitively normal control subjects. All participants underwent ophthalmological screening to exclude interfering ocular disease. Using a multimodal approach, we measured retinal vascular parameters, choroidal thickness, macular vascular density, and foveal avascular zone size. Results We found no disease effects on retinal vascular measures (all β's < |0.15|, all P > .2), adjusted for confounders. Venular tortuosity was inversely associated with Fazekas score in control subjects (β -0.56, P < .01), while vessel density in the outer ring of the macula was inversely associated with Fazekas score in AD cases (β -0.64, P < .01). Discussion In conclusion, retinal vasculature did not discriminate patients with AD from control subjects, despite evident changes on clinical, neuroimaging, and cerebrospinal fluid biomarkers, challenging the use of retinal vasculature measurements as AD biomarker.
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Affiliation(s)
- Jurre den Haan
- Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam UMC, Amsterdam, The Netherlands
| | - Jacoba A van de Kreeke
- Department of Ophthalmology, Vrije Universiteit Amsterdam, Amsterdam UMC, Amsterdam, The Netherlands
| | - Bart N van Berckel
- Department of Radiology and Nuclear Medicine, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam UMC, Amsterdam, The Netherlands
| | - Frederik Barkhof
- Department of Radiology and Nuclear Medicine, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam UMC, Amsterdam, The Netherlands.,UCL institutes of Neurology and Healthcare Engineering, London, UK
| | - Charlotte E Teunissen
- Neurochemistry Lab and Biobank, Department of Clinical Chemistry, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam UMC, Amsterdam, The Netherlands
| | - Philip Scheltens
- Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam UMC, Amsterdam, The Netherlands
| | - Frank D Verbraak
- Department of Ophthalmology, Vrije Universiteit Amsterdam, Amsterdam UMC, Amsterdam, The Netherlands
| | - Femke H Bouwman
- Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam UMC, Amsterdam, The Netherlands
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Cerquera-Jaramillo MA, Nava-Mesa MO, González-Reyes RE, Tellez-Conti C, de-la-Torre A. Visual Features in Alzheimer's Disease: From Basic Mechanisms to Clinical Overview. Neural Plast 2018; 2018:2941783. [PMID: 30405709 PMCID: PMC6204169 DOI: 10.1155/2018/2941783] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 08/07/2018] [Indexed: 12/16/2022] Open
Abstract
Alzheimer's disease (AD) is the leading cause of dementia worldwide. It compromises patients' daily activities owing to progressive cognitive deterioration, which has elevated direct and indirect costs. Although AD has several risk factors, aging is considered the most important. Unfortunately, clinical diagnosis is usually performed at an advanced disease stage when dementia is established, making implementation of successful therapeutic interventions difficult. Current biomarkers tend to be expensive, insufficient, or invasive, raising the need for novel, improved tools aimed at early disease detection. AD is characterized by brain atrophy due to neuronal and synaptic loss, extracellular amyloid plaques composed of amyloid-beta peptide (Aβ), and neurofibrillary tangles of hyperphosphorylated tau protein. The visual system and central nervous system share many functional components. Thus, it is plausible that damage induced by Aβ, tau, and neuroinflammation may be observed in visual components such as the retina, even at an early disease stage. This underscores the importance of implementing ophthalmological examinations, less invasive and expensive than other biomarkers, as useful measures to assess disease progression and severity in individuals with or at risk of AD. Here, we review functional and morphological changes of the retina and visual pathway in AD from pathophysiological and clinical perspectives.
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Affiliation(s)
| | - Mauricio O. Nava-Mesa
- Grupo de Investigación en Neurociencias (NeURos), Escuela de Medicina y Ciencias de la Salud, Universidad del Rosario, Bogotá, Colombia
| | - Rodrigo E. González-Reyes
- Grupo de Investigación en Neurociencias (NeURos), Escuela de Medicina y Ciencias de la Salud, Universidad del Rosario, Bogotá, Colombia
| | - Carlos Tellez-Conti
- Escuela Superior de Oftalmología-Instituto Barraquer de América, Bogotá, Colombia
| | - Alejandra de-la-Torre
- Grupo de Investigación en Neurociencias (NeURos), Escuela de Medicina y Ciencias de la Salud, Universidad del Rosario, Bogotá, Colombia
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Sajdak BS, Bell BA, Lewis TR, Luna G, Cornwell GS, Fisher SK, Merriman DK, Carroll J. Assessment of Outer Retinal Remodeling in the Hibernating 13-Lined Ground Squirrel. Invest Ophthalmol Vis Sci 2018; 59:2538-2547. [PMID: 29847661 PMCID: PMC5967598 DOI: 10.1167/iovs.17-23120] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Accepted: 04/20/2018] [Indexed: 12/25/2022] Open
Abstract
Purpose We examined outer retinal remodeling of the euthermic and torpid cone-dominant 13-lined ground squirrel (13-LGS) retina using optical coherence tomography (OCT) imaging and histology. Methods Retinas and corneas of living 13-LGSs were imaged during euthermic and torpid physiological states using OCT. Retinal layer thickness was measured at the visual streak from registered and averaged vertical B-scans. Following OCT, some retinas were collected immediately for postmortem histologic comparison using light microscopy, immunofluorescence, or transmission electron microscopy. Results Compared to OCT images from euthermic retinae, OCT images of torpid retinae revealed significantly thicker inner and outer nuclear layers, as well as increases in the distances between outer retinal reflectivity bands 1 and 2, and bands 3 and 4. A significant decrease in the distance between bands 2 and 3 also was seen, alongside significant thinning of the choriocapillaris and choroid. OCT image quality was reduced in torpid eyes, partly due to significant thickening of the corneal stroma during this state. Conclusions The torpid retina of the hibernating 13-LGS undergoes structural changes that can be detected by OCT imaging. Comparisons between in vivo OCT and ex vivo histomorphometry may offer insight to the origin of hyperreflective OCT bands within the outer retina of the cone-dominant 13-LGS.
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Affiliation(s)
- Benjamin S. Sajdak
- Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Brent A. Bell
- Cole Eye Institute/Ophthalmic Research, Cleveland Clinic, Cleveland, Ohio, United States
| | - Tylor R. Lewis
- Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Gabriel Luna
- Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, California, United States
| | - Grayson S. Cornwell
- Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, California, United States
| | - Steven K. Fisher
- Neuroscience Research Institute, University of California Santa Barbara, Santa Barbara, California, United States
| | - Dana K. Merriman
- Biology & Microbiology, University of Wisconsin Oshkosh, Oshkosh, Wisconsin, United States
| | - Joseph Carroll
- Cell Biology, Neurobiology and Anatomy, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Biophysics, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
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