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Sun Y, Zhang L, Ye H, Leng L, Chen Y, Su Y, Ren P, Lu H, Peng G. Potential ocular indicators to distinguish posterior cortical atrophy and typical Alzheimer's disease: a cross-section study using optical coherence tomography angiography. Alzheimers Res Ther 2024; 16:64. [PMID: 38528626 PMCID: PMC10962115 DOI: 10.1186/s13195-024-01431-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 03/18/2024] [Indexed: 03/27/2024]
Abstract
BACKGROUND Posterior cortical atrophy (PCA) is a form of dementia that frequently displays significant visual dysfunction and relatively preserved cognitive and executive functions, thus hindering early diagnosis and treatment. This study aimed to investigate possible fundus markers in PCA patients and compare them with those of typical Alzheimer's disease (AD) patients to seek potential diagnostic patterns. METHODS Age-matched PCA and AD patients and healthy controls (HC) completed optometry, intraocular pressure measurement, neuropsychologic assessments, optical coherence tomography (OCT), and optical coherence tomography angiography (OCTA) examination in one visit. Overall, six outcomes of thicknesses of various retinal layers and seven outcomes of the retinal microvascular network were calculated. After adjusting for age, sex, and years of education, the OCT and OCTA results were analyzed using analysis of covariance and generalized linear models. Correlation analyses were performed using Spearman correlation, and ROC curves were plotted. RESULTS Twelve PCA patients, nineteen AD patients, and thirty HC, aged 45-80 years were included. Fifty HC, thirty AD, and twenty PCA eyes were available for foveal avascular zone (FAZ) area analysis; forty-nine HC, thirty-four AD, and eighteen PCA eyes were available for OCT and OCTA assessments. PCA patients had thinner retinal nerve fiber layer and ganglion cell layer + inner plexiform layer than HC in the 0-3 mm circle and 1-3 mm ring. Few structural differences were observed between the AD group and the other two groups. The flow area of the superficial capillary plexus and the intermediate capillary plexus was smaller in the PCA group than in the HC group in the 0-1 mm circle, 0-3 mm circle. MMSE performed better than any combination of optical parameters in identifying AD and PCA from HC (AUC = 1), while the combination of MoCA, retinal thickness and vascular density of ICP in the 1-3 mm ring, with flow area of ICP in the 0-1 mm circle showed the strongest ability to distinguish PCA from AD (AUC = 0.944). CONCLUSIONS PCA patients exhibited similar impairment patterns to AD patients in the fundus structure and microvascular network. OCTA may aid in the non-invasive detection of AD and PCA, but still remains to be substantiated.
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Affiliation(s)
- Yan Sun
- Department of Neurology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Lumi Zhang
- Department of Neurology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Hui Ye
- Department of Ophthalmology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Lumin Leng
- Department of Neurology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Yi Chen
- Department of Neurology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Yujie Su
- Department of Neurology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Peifang Ren
- Department of Ophthalmology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China
| | - Hong Lu
- Department of Ophthalmology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China.
| | - Guoping Peng
- Department of Neurology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, People's Republic of China.
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Suh A, Ong J, Kamran SA, Waisberg E, Paladugu P, Zaman N, Sarker P, Tavakkoli A, Lee AG. Retina Oculomics in Neurodegenerative Disease. Ann Biomed Eng 2023; 51:2708-2721. [PMID: 37855949 DOI: 10.1007/s10439-023-03365-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 09/05/2023] [Indexed: 10/20/2023]
Abstract
Ophthalmic biomarkers have long played a critical role in diagnosing and managing ocular diseases. Oculomics has emerged as a field that utilizes ocular imaging biomarkers to provide insights into systemic diseases. Advances in diagnostic and imaging technologies including electroretinography, optical coherence tomography (OCT), confocal scanning laser ophthalmoscopy, fluorescence lifetime imaging ophthalmoscopy, and OCT angiography have revolutionized the ability to understand systemic diseases and even detect them earlier than clinical manifestations for earlier intervention. With the advent of increasingly large ophthalmic imaging datasets, machine learning models can be integrated into these ocular imaging biomarkers to provide further insights and prognostic predictions of neurodegenerative disease. In this manuscript, we review the use of ophthalmic imaging to provide insights into neurodegenerative diseases including Alzheimer Disease, Parkinson Disease, Amyotrophic Lateral Sclerosis, and Huntington Disease. We discuss recent advances in ophthalmic technology including eye-tracking technology and integration of artificial intelligence techniques to further provide insights into these neurodegenerative diseases. Ultimately, oculomics opens the opportunity to detect and monitor systemic diseases at a higher acuity. Thus, earlier detection of systemic diseases may allow for timely intervention for improving the quality of life in patients with neurodegenerative disease.
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Affiliation(s)
- Alex Suh
- Tulane University School of Medicine, New Orleans, LA, USA.
| | - Joshua Ong
- Michigan Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Sharif Amit Kamran
- Human-Machine Perception Laboratory, Department of Computer Science and Engineering, University of Nevada, Reno, Reno, NV, USA
| | - Ethan Waisberg
- University College Dublin School of Medicine, Belfield, Dublin, Ireland
| | - Phani Paladugu
- Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
- Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - Nasif Zaman
- Human-Machine Perception Laboratory, Department of Computer Science and Engineering, University of Nevada, Reno, Reno, NV, USA
| | - Prithul Sarker
- Human-Machine Perception Laboratory, Department of Computer Science and Engineering, University of Nevada, Reno, Reno, NV, USA
| | - Alireza Tavakkoli
- Human-Machine Perception Laboratory, Department of Computer Science and Engineering, University of Nevada, Reno, Reno, NV, USA
| | - Andrew G Lee
- Center for Space Medicine, Baylor College of Medicine, Houston, TX, USA
- Department of Ophthalmology, Blanton Eye Institute, Houston Methodist Hospital, 6560 Fannin St #450, Houston, TX, 77030, USA
- The Houston Methodist Research Institute, Houston Methodist Hospital, Houston, TX, USA
- Departments of Ophthalmology, Neurology and Neurosurgery, Weill Cornell Medicine, New York, NY, USA
- Department of Ophthalmology, University of Texas Medical Branch, Galveston, TX, USA
- University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Texas A&M College of Medicine, Bryan, TX, USA
- Department of Ophthalmology, The University of Iowa Hospitals and Clinics, Iowa City, IA, USA
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Hussain A, Sheikh Z, Subramanian M. The Eye as a Diagnostic Tool for Alzheimer’s Disease. Life (Basel) 2023; 13:life13030726. [PMID: 36983883 PMCID: PMC10052959 DOI: 10.3390/life13030726] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2023] [Revised: 02/23/2023] [Accepted: 03/04/2023] [Indexed: 03/10/2023] Open
Abstract
Alzheimer’s disease (AD) is a progressive neurodegenerative disorder impacting cognition, function, and behavior in the elderly population. While there are currently no disease-modifying agents capable of curing AD, early diagnosis and management in the preclinical stage can significantly improve patient morbidity and life expectancy. Currently, the diagnosis of Alzheimer’s disease is a clinical one, often supplemented by invasive and expensive biomarker testing. Over the last decade, significant advancements have been made in our understanding of AD and the role of ocular tissue as a potential biomarker. Ocular biomarkers hold the potential to provide noninvasive and easily accessible diagnostic and monitoring capabilities. This review summarizes current research for detecting biomarkers of Alzheimer’s disease in ocular tissue.
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Wang L, Hu Z, Chen H, Sheng X, Qin R, Shao P, Yang Z, Yao W, Zhao H, Xu Y, Bai F. Applying Retinal Vascular Structures Characteristics Coupling with Cortical Visual System in Alzheimer's Disease Spectrum Patients. Brain Sci 2023; 13:brainsci13020339. [PMID: 36831883 PMCID: PMC9954049 DOI: 10.3390/brainsci13020339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 02/08/2023] [Accepted: 02/14/2023] [Indexed: 02/19/2023] Open
Abstract
Cortical visual system dysfunction is closely related to the progression of Alzheimer's Disease (AD), while retinal vascular structures play an important role in the integrity of the function of the visual network and are a potential biomarker of AD. This study explored the association between the cortical visual system and retinal vascular structures in AD-spectrum patients, and it established a screening tool to detect preclinical AD based on these parameters identified in a retinal examination. A total of 42 subjects were enrolled and were distributed into two groups: 22 patients with cognitive impairment and 20 healthy controls. All participants underwent neuropsychological tests, optical coherence tomography angiography and resting-state fMRI imaging. Seed-based functional connectivity analysis was used to construct the cortical visual network. The association of functional connectivity of the cortical visual system and retinal vascular structures was further explored in these subjects. This study found that the cognitive impairment group displayed prominently decreased functional connectivity of the cortical visual system mainly involving the right inferior temporal gyrus, left supramarginal gyrus and right postcentral gyrus. Meanwhile, we observed that retinal vascular structure characteristics deteriorated with the decline in functional connectivity in the cortical visual system. Our study provided novel insights into the aberrant cortical visual system in patients with cognitive impairment that strongly emphasized the critical role of retinal vascular structure characteristics, which could be used as potential biomarkers for diagnosing and monitoring the progression of AD.
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Affiliation(s)
- Lianlian Wang
- Department of Neurology, Nanjing Drum Tower Hospital Clinical College of Jiangsu University, Nanjing 210008, China
| | - Zheqi Hu
- Department of Neurology, Nanjing Drum Tower Hospital of the Affiliated Hospital of Nanjing University Medical School, the State Key Laboratory of Pharmaceutical Biotechnology, Institute of Brain Science, Nanjing University, Nanjing 210008, China
| | - Haifeng Chen
- Department of Neurology, Nanjing Drum Tower Hospital of the Affiliated Hospital of Nanjing University Medical School, the State Key Laboratory of Pharmaceutical Biotechnology, Institute of Brain Science, Nanjing University, Nanjing 210008, China
- Jiangsu Province Stroke Center for Diagnosis and Therapy, Nanjing 210008, China
- Nanjing Neuropsychiatry Clinic Medical Center, Nanjing 210008, China
| | - Xiaoning Sheng
- Department of Neurology, Nanjing Drum Tower Hospital of the Affiliated Hospital of Nanjing University Medical School, the State Key Laboratory of Pharmaceutical Biotechnology, Institute of Brain Science, Nanjing University, Nanjing 210008, China
| | - Ruomeng Qin
- Department of Neurology, Nanjing Drum Tower Hospital of the Affiliated Hospital of Nanjing University Medical School, the State Key Laboratory of Pharmaceutical Biotechnology, Institute of Brain Science, Nanjing University, Nanjing 210008, China
- Jiangsu Province Stroke Center for Diagnosis and Therapy, Nanjing 210008, China
- Nanjing Neuropsychiatry Clinic Medical Center, Nanjing 210008, China
| | - Pengfei Shao
- Department of Neurology, Nanjing Drum Tower Hospital of the Affiliated Hospital of Nanjing University Medical School, the State Key Laboratory of Pharmaceutical Biotechnology, Institute of Brain Science, Nanjing University, Nanjing 210008, China
| | - Zhiyuan Yang
- Department of Neurology, Nanjing Drum Tower Hospital of the Affiliated Hospital of Nanjing University Medical School, the State Key Laboratory of Pharmaceutical Biotechnology, Institute of Brain Science, Nanjing University, Nanjing 210008, China
| | - Weina Yao
- Department of Neurology, Nanjing Drum Tower Hospital Clinical College of Jiangsu University, Nanjing 210008, China
| | - Hui Zhao
- Department of Neurology, Nanjing Drum Tower Hospital of the Affiliated Hospital of Nanjing University Medical School, the State Key Laboratory of Pharmaceutical Biotechnology, Institute of Brain Science, Nanjing University, Nanjing 210008, China
- Jiangsu Province Stroke Center for Diagnosis and Therapy, Nanjing 210008, China
- Nanjing Neuropsychiatry Clinic Medical Center, Nanjing 210008, China
| | - Yun Xu
- Department of Neurology, Nanjing Drum Tower Hospital of the Affiliated Hospital of Nanjing University Medical School, the State Key Laboratory of Pharmaceutical Biotechnology, Institute of Brain Science, Nanjing University, Nanjing 210008, China
- Jiangsu Province Stroke Center for Diagnosis and Therapy, Nanjing 210008, China
- Nanjing Neuropsychiatry Clinic Medical Center, Nanjing 210008, China
| | - Feng Bai
- Department of Neurology, Nanjing Drum Tower Hospital of the Affiliated Hospital of Nanjing University Medical School, the State Key Laboratory of Pharmaceutical Biotechnology, Institute of Brain Science, Nanjing University, Nanjing 210008, China
- Jiangsu Province Stroke Center for Diagnosis and Therapy, Nanjing 210008, China
- Nanjing Neuropsychiatry Clinic Medical Center, Nanjing 210008, China
- Geriatric Medicine Center, Affiliated Taikang Xianlin Drum Tower Hospital, Medical School of Nanjing University, Nanjing 210008, China
- Correspondence: ; Tel.: +86-25-83105960
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Gharbiya M, Visioli G, Trebbastoni A, Albanese GM, Colardo M, D’Antonio F, Segatto M, Lambiase A. Beta-Amyloid Peptide in Tears: An Early Diagnostic Marker of Alzheimer's Disease Correlated with Choroidal Thickness. Int J Mol Sci 2023; 24:ijms24032590. [PMID: 36768913 PMCID: PMC9917300 DOI: 10.3390/ijms24032590] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 01/21/2023] [Accepted: 01/28/2023] [Indexed: 01/31/2023] Open
Abstract
We aimed to evaluate the diagnostic role of Alzheimer's disease (AD) biomarkers in tears as well as their association with retinal and choroidal microstructures. In a cross-sectional study, 35 subjects (age 71.7 ± 6.9 years) were included: 11 with prodromal AD (MCI), 10 with mild-to-moderate AD, and 14 healthy controls. The diagnosis of AD and MCI was confirmed according to a complete neuropsychological evaluation and PET or MRI imaging. After tear sample collection, β-amyloid peptide Aβ1-42 concentration was analyzed using ELISA, whereas C-terminal fragments of the amyloid precursor protein (APP-CTF) and phosphorylated tau (p-tau) were assessed by Western blot. Retinal layers and choroidal thickness (CT) were acquired by spectral-domain optical coherence tomography (SD-OCT). Aβ1-42 levels in tears were able to detect both MCI and AD patients with a specificity of 93% and a sensitivity of 81% (AUC = 0.91). Tear levels of Aβ1-42 were lower, both in the MCI (p < 0.01) and in the AD group (p < 0.001) when compared to healthy controls. Further, Aβ1-42 was correlated with psychometric scores (p < 0.001) and CT (p < 0.01). CT was thinner in the affected patients (p = 0.035). No differences were observed for APP-CTF and p-tau relative abundance in tears. Testing Aβ1-42 levels in tears seems to be a minimally invasive, cost-saving method for early detection and diagnosis of AD.
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Affiliation(s)
- Magda Gharbiya
- Department of Sense Organs, Sapienza University of Rome, 155, Viale del Policlinico, 00161 Rome, Italy
- Correspondence: ; Tel.: +39-06-49975389; Fax: +39-06-49975388
| | - Giacomo Visioli
- Department of Sense Organs, Sapienza University of Rome, 155, Viale del Policlinico, 00161 Rome, Italy
| | | | - Giuseppe Maria Albanese
- Department of Sense Organs, Sapienza University of Rome, 155, Viale del Policlinico, 00161 Rome, Italy
| | - Mayra Colardo
- Department of Biosciences and Territory, University of Molise, 86100 Campobasso, Italy
| | - Fabrizia D’Antonio
- Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
| | - Marco Segatto
- Department of Biosciences and Territory, University of Molise, 86100 Campobasso, Italy
| | - Alessandro Lambiase
- Department of Sense Organs, Sapienza University of Rome, 155, Viale del Policlinico, 00161 Rome, Italy
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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: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [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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Vij R, Arora S. A systematic survey of advances in retinal imaging modalities for Alzheimer's disease diagnosis. Metab Brain Dis 2022; 37:2213-2243. [PMID: 35290546 DOI: 10.1007/s11011-022-00927-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 02/04/2022] [Indexed: 01/06/2023]
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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Jeevakumar V, Sefton R, Chan J, Gopinath B, Liew G, Shah TM, Siette J. Association between retinal markers and cognition in older adults: a systematic review. BMJ Open 2022; 12:e054657. [PMID: 35728906 PMCID: PMC9214387 DOI: 10.1136/bmjopen-2021-054657] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVES To appraise the existing literature reporting an association between retinal markers and cognitive impairment in adults aged 65 years and over and to provide directions for future use of retinal scanning as a potential tool for dementia diagnosis. DESIGN Systematic review of peer-reviewed empirical articles investigating the association of retinal markers in assessing cognitive impairment. DATA SOURCES Three electronic databases, Medline, PsycINFO and EMBASE were searched from inception until March 2022. ELIGIBILITY CRITERIA All empirical articles in English investigating the association between retinal markers and cognition in humans aged ≥65 years using various retinal scanning methodologies were included. Studies with no explicit evaluation of retinal scanning and cognitive outcomes were excluded. Risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool. DATA EXTRACTION AND SYNTHESIS Data extraction was conducted by two authors (VJ, RS) and reviewed by another author (JS). Results were synthesised and described narratively. RESULTS Sixty-seven eligible studies examining 6815 older adults were included. Majority of studies were cross-sectional (n=60; 89.6%). Optical coherence tomography (OCT) was the most commonly used retinal scanning methodology to measure the thickness of retinal nerve fibre layer, the ganglion cell complex, choroid and macula. 51.1% of cross-sectional studies using OCT reported an association between the thinning of at least one retinal parameter and poor cognition. Longitudinal studies (n=6) using OCT also mostly identified significant reductions in retinal nerve fibre layer thickness with cognitive decline. Study quality was overall moderate. CONCLUSION Retinal nerve fibre layer thickness is linked with cognitive performance and therefore may have the potential to detect cognitive impairment in older adults. Further longitudinal studies are required to validate our synthesis and understand underlying mechanisms before recommending implementation of OCT as a dementia screening tool in clinical practice. PROSPERO REGISTRATION NUMBER CRD42020176757.
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Affiliation(s)
- Varshanie Jeevakumar
- Australian Institute of Health Innovation, Macquarie University, Macquarie Park, New South Wales, Australia
| | - Rebekah Sefton
- Australian Institute of Health Innovation, Macquarie University, Macquarie Park, New South Wales, Australia
| | - Joyce Chan
- New Look Eyewear, Maitland, New South Wales, Australia
| | - Bamini Gopinath
- Department of Linguistics, Australian Hearing Hub, Macquarie University, Macquarie Park, New South Wales, Australia
| | - Gerald Liew
- Centre for Vision Research, The University of Sydney, Sydney, New South Wales, Australia
| | - Tejal M Shah
- Macquarie Medical School, Macquarie University, North Ryde, New South Wales, Australia
| | - Joyce Siette
- Australian Institute of Health Innovation, Macquarie University, Macquarie Park, New South Wales, Australia
- MARCS Institute for Brain, Behaviour and Development, Western Sydney University, Westmead, New South Wales, Australia
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