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Tang QY, Zhong YL, Wang XM, Huang BL, Qin WG, Huang X. Machine Learning Analysis Classifies Patients with Primary Angle-Closure Glaucoma Using Abnormal Brain White Matter Function. Clin Ophthalmol 2024; 18:659-670. [PMID: 38468914 PMCID: PMC10926922 DOI: 10.2147/opth.s451872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Accepted: 02/05/2024] [Indexed: 03/13/2024] Open
Abstract
Objective Primary angle-closure glaucoma (PACG) is a globally prevalent, irreversible eye disease leading to blindness. Previous neuroimaging studies demonstrated that PACG patients were associated with gray matter function changes. However, whether the white matter(WM) function changes in PACG patients remains unknown. The purpose of the study is to investigate WM function changes in the PACG patients. Methods In total, 40 PACG patients and 40 well-matched HCs participated in our study and underwent resting-state functional magnetic resonance imaging (rs-fMRI) scans. We compared between-group differences between PACG patients and HC in the WM function using amplitude of low-frequency fluctuations (ALFF). In addition, the SVM method was applied to the construction of the PACG classification model. Results Compared with the HC group, ALFF was attenuated in right posterior thalamic radiation (include optic radiation), splenium of corpus callosum, and left tapetum in the PACG group, the results are statistically significant (GRF correction, voxel-level P < 0.001, cluster-level P < 0.05). Furthermore, the SVM classification had an accuracy of 80.0% and an area under the curve (AUC) of 0.86 for distinguishing patients with PACG from HC. Conclusion The findings of our study uncover abnormal WM functional alterations in PACG patients and mainly involves vision-related regions. These findings provide new insights into widespread brain damage in PACG from an alternative WM functional perspective.
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Affiliation(s)
- Qiu-Yu Tang
- College of Clinical Medicine, Jiangxi University of Chinese Medicine, Nanchang City, Jiangxi, 330004, People’s Republic of China
| | - Yu-Lin Zhong
- Department of Ophthalmology, Jiangxi Provincial People’s Hospital, The First Affiliated Hospital of Nanchang Medical College, Nanchang, Jiangxi, 330006, People’s Republic of China
| | - Xin-Miao Wang
- School of Ophthalmology and Optometry, Jiangxi Medical College, Nanchang University, Nanchang, Jiangxi, 330000, People’s Republic of China
| | - Bing-Lin Huang
- College of Clinical Medicine, Jiangxi University of Chinese Medicine, Nanchang City, Jiangxi, 330004, People’s Republic of China
| | - Wei-Guo Qin
- Department of Cardiothoracic Surgery, The 908th Hospital of Chinese People’s Liberation Army Joint Logistic Support Force’, Nanchang, People’s Republic of China
| | - Xin Huang
- Department of Ophthalmology, Jiangxi Provincial People’s Hospital, The First Affiliated Hospital of Nanchang Medical College, Nanchang, Jiangxi, 330006, People’s Republic of China
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2
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Pang Y, Tan Z, Chen X, Liao Z, Yang X, Zhong Q, Huang B, Zhong Q, Zhong J, Mo W. Evaluation of preoperative visual pathway impairment in patients with non-functioning pituitary adenoma using diffusion tensor imaging coupled with optical coherence tomography. Front Neurosci 2023; 17:1057781. [PMID: 36845438 PMCID: PMC9947395 DOI: 10.3389/fnins.2023.1057781] [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: 09/30/2022] [Accepted: 01/17/2023] [Indexed: 02/11/2023] Open
Abstract
Objective Optic chiasma compression and associated visual impairment induced by a non-functioning pituitary adenoma (NFPA) is commonly assessed by the optic disk and retina but is inadequate to understand the entire visual pathway impairment. We aim to evaluate the use of optical coherence tomography (OCT) coupled with diffusion tensor imaging (DTI) for the preoperative evaluation of visual pathway impairment. Methods Fifty-three patients with NFPA (categorized into mild and heavy compression subgroups) were subjected to OCT to calculate the thickness of the circumpapillary retinal nerve fiber layer (CP-RNFL), macular ganglion cell complex (GCC), macular ganglion cell layer (GCL), and macular inner plexus layer (IPL), as well as to DTI to calculate the fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values. Results Compared to mild compression, heavy compression caused decreased FA value, increased ADC value of several segments of the visual pathway, thin temporal CP-RNFL, and quadrant macular GCC, IPL, and GCL. Average CP-RNFL thickness, inferior-macular inner-ring IPL and GCC thicknesses, inferior CP-RNFL thickness, and superior CP-RNFL thickness were the best indicators of the impairment of the optic nerve, optic chiasma, optic tract, and optic radiation, respectively. Conclusion DTI and OCT parameters can effectively evaluate visual pathway impairment and are beneficial for the objective preoperative evaluation of visual pathway impairment in patients with NFPA.
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Affiliation(s)
- Yanhua Pang
- Department of Ophthalmology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, China
| | - Zhi Tan
- Department of Radiology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, China
| | - Xinxin Chen
- Teaching and Research Center of Medical Communication Science, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, China
| | - Zhihui Liao
- Department of Ophthalmology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, China
| | - Xin Yang
- Department of Ophthalmology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, China
| | - Qin Zhong
- Department of Radiology, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, China
| | - Baqi Huang
- Department of Neurosurgery, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, China
| | - Qianshuo Zhong
- Department of Neurosurgery, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, China
| | - Jingxiang Zhong
- Department of Ophthalmology, The First Affiliated Hospital of Jinan University, Guangzhou, China,Department of Ophthalmology, The Sixth Affiliated Hospital of Jinan University, Guangzhou, China,*Correspondence: Jingxiang Zhong,
| | - Wei Mo
- Department of Neurosurgery, Affiliated Hospital of Guangdong Medical University, Zhanjiang, Guangdong, China,Wei Mo,
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Wang J, Zhang Y, Meng X, Liu G. Application of diffusion tensor imaging technology in glaucoma diagnosis. Front Neurosci 2023; 17:1125638. [PMID: 36816120 PMCID: PMC9932933 DOI: 10.3389/fnins.2023.1125638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 01/11/2023] [Indexed: 02/05/2023] Open
Abstract
Glaucoma is the first major category of irreversible blinding eye illnesses worldwide. Its leading cause is the death of retinal ganglion cells and their axons, which results in the loss of vision. Research indicates that glaucoma affects the optic nerve and the whole visual pathway. It also reveals that degenerative lesions caused by glaucoma can be found outside the visual pathway. Diffusion tensor imaging (DTI) is a magnetic resonance imaging (MRI) technique that can investigate the complete visual system, including alterations in the optic nerve, optic chiasm, optic tract, lateral geniculate nuclear, and optic radiation. In order to provide a more solid foundation for the degenerative characteristics of glaucoma, this paper will discuss the standard diagnostic techniques for glaucoma through a review of the literature, describe the use of DTI technology in glaucoma in humans and animal models, and introduce these techniques. With the advancement of DTI technology and its coupling with artificial intelligence, DTI represents a potential future for MRI technology in glaucoma research.
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Li R, Li J, Wang Z. Quantitative assessment of the intraorbital segment of the optic nerve in patients with thyroid orbitopathy using diffusion tensor imaging. Acta Radiol 2023; 64:725-731. [PMID: 35291830 DOI: 10.1177/02841851221082419] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND It is difficult to detect optic nerve changes in patients with thyroid-associated ophthalmopathy (TAO) before the development of optic neuropathy. PURPOSE To detect changes in the intraorbital segment of the optic nerve in patients with TAO using diffusion tensor imaging (DTI) and determine any correlations with disease severity. MATERIAL AND METHODS A total of 74 participants (17 normal, 22 mild, and 35 moderate-severe TAO) were organized to be given 3-T DTI to measure fractional anisotropy (FA) and mean diffusivity (MD) for the orbital segments of their optic nerves. All underwent ophthalmological examinations for visual acuity, intraocular pressure, exophthalmos, and fundoscopy, and were assessed based on the Clinical Activity Score (CAS). Univariate analysis of variance and Pearson's correlation coefficients were carried out. RESULTS Patients with moderate-to-severe TAO had significantly lower FA values and higher MD values (P < 0.05). FA values were negatively correlated with CAS but had no obvious correlations with the degree of exophthalmos. MD values had no obvious correlations with CAS or the degree of exophthalmos. CONCLUSION DTI parameters of the intraorbital optic nerves were significantly altered in moderate-to-severe patients before onset of clinical optic nerve dysfunction and may, therefore, be used as an imaging biomarker for assessing the disease.
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Affiliation(s)
- Rui Li
- Beijing Friendship Hospital, 26455Capital Medical University, Beijing, PR China
| | - Jing Li
- Beijing Friendship Hospital, 26455Capital Medical University, Beijing, PR China
| | - Zhenchang Wang
- Beijing Friendship Hospital, 26455Capital Medical University, Beijing, PR China
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Haykal S, Invernizzi A, Carvalho J, Jansonius NM, Cornelissen FW. Microstructural Visual Pathway White Matter Alterations in Primary Open-Angle Glaucoma: A Neurite Orientation Dispersion and Density Imaging Study. AJNR Am J Neuroradiol 2022; 43:756-763. [PMID: 35450857 PMCID: PMC9089264 DOI: 10.3174/ajnr.a7495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 02/26/2022] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE DTI studies of patients with primary open-angle glaucoma have demonstrated that glaucomatous degeneration is not confined to the retina but involves the entire visual pathway. Due to the lack of direct biologic interpretation of DTI parameters, the structural nature of this degeneration is still poorly understood. We used neurite orientation dispersion and density imaging (NODDI) to characterize the microstructural changes in the pregeniculate optic tracts and the postgeniculate optic radiations of patients with primary open-angle glaucoma, to better understand the mechanisms underlying these changes. MATERIALS AND METHODS T1- and multishell diffusion-weighted scans were obtained from 23 patients with primary open-angle glaucoma and 29 controls. NODDI parametric maps were produced from the diffusion-weighted scans, and probabilistic tractography was used to track the optic tracts and optic radiations. NODDI parameters were computed for the tracked pathways, and the measures were compared between both groups. The retinal nerve fiber layer thickness and visual field loss were assessed for the patients with glaucoma. RESULTS The optic tracts of the patients with glaucoma showed a higher orientation dispersion index and a lower neurite density index compared with the controls (P < .001 and P = .001, respectively), while their optic radiations showed a higher orientation dispersion index only (P = .003). CONCLUSIONS The pregeniculate visual pathways of the patients with primary open-angle glaucoma exhibited a loss of both axonal coherence and density, while the postgeniculate pathways exhibited a loss of axonal coherence only. Further longitudinal studies are needed to assess the progression of NODDI alterations in the visual pathways of patients with primary open-angle glaucoma across time.
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Affiliation(s)
- S Haykal
- From the Laboratory for Experimental Ophthalmology (S.H., A.I., J.C., F.W.C.)
| | - A Invernizzi
- From the Laboratory for Experimental Ophthalmology (S.H., A.I., J.C., F.W.C.)
| | - J Carvalho
- From the Laboratory for Experimental Ophthalmology (S.H., A.I., J.C., F.W.C.)
| | - N M Jansonius
- Department of Ophthalmology (N.M.J.), University of Groningen, University Medical Center Groningen, Groningen, the Netherlands
| | - F W Cornelissen
- From the Laboratory for Experimental Ophthalmology (S.H., A.I., J.C., F.W.C.)
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Visual Tract Degradation in Bilateral Normal-Tension Glaucoma-Cortical Thickness Maps and Volumetric Study of Visual Pathway Areas. J Clin Med 2022; 11:jcm11071907. [PMID: 35407515 PMCID: PMC8999724 DOI: 10.3390/jcm11071907] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 03/14/2022] [Accepted: 03/26/2022] [Indexed: 02/01/2023] Open
Abstract
The aim of the study was to evaluate changes in the central visual pathways during the early and advanced stages of bilateral normal-tension glaucoma (NTG). METHODS The studied groups constituted patients with bilateral normal-tension glaucoma of the same stage (n = 45) and age-matched healthy volunteers (n = 17). All patients underwent ophthalmic examination and examination on a 1.5 Tesla Magnetic Resonance Scanner (Optima 360, GE Healthcare). Volume and cortical thickness analyses were performed using the open-source automated software package FreeSurfer. RESULTS There was a significant difference in lateral geniculate nuclei volume between the control and advanced glaucoma groups in the right hemisphere (p = 0.03) and in the left hemisphere between the early and advanced glaucoma patients (p = 0.026). The optic chiasm volume differed significantly between the control and advanced NTG groups (p = 0.0003) and between early and advanced glaucoma patients (p = 0.004). Mean cortical thickness analysis revealed a significant increase in values in the advanced glaucoma group in the right Brodmann area 17 (BA17) (p = 0.007) and right BA18 (p = 0.049) as compared to early NTG. In the left BA18 area, the mean thickness of the cortex in the early glaucoma group was significantly lower than in the control group (p = 0.03). CONCLUSIONS The increase in the grey matter thickness in the V1 region with more-advanced glaucoma stages may reflect compensatory hypertrophy. Additionally, the regions of the brain early affected during glaucoma with reduced thickness were the right lateral occipital gyrus and left lingual gyrus. The most prominent change during the course of glaucoma was the increase in grey matter thickness in the right cuneus.
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Mendoza M, Shotbolt M, Faiq MA, Parra C, Chan KC. Advanced Diffusion MRI of the Visual System in Glaucoma: From Experimental Animal Models to Humans. BIOLOGY 2022; 11:454. [PMID: 35336827 PMCID: PMC8945790 DOI: 10.3390/biology11030454] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 03/10/2022] [Indexed: 11/18/2022]
Abstract
Glaucoma is a group of ophthalmologic conditions characterized by progressive retinal ganglion cell death, optic nerve degeneration, and irreversible vision loss. While intraocular pressure is the only clinically modifiable risk factor, glaucoma may continue to progress at controlled intraocular pressure, indicating other major factors in contributing to the disease mechanisms. Recent studies demonstrated the feasibility of advanced diffusion magnetic resonance imaging (dMRI) in visualizing the microstructural integrity of the visual system, opening new possibilities for non-invasive characterization of glaucomatous brain changes for guiding earlier and targeted intervention besides intraocular pressure lowering. In this review, we discuss dMRI methods currently used in visual system investigations, focusing on the eye, optic nerve, optic tract, subcortical visual brain nuclei, optic radiations, and visual cortex. We evaluate how conventional diffusion tensor imaging, higher-order diffusion kurtosis imaging, and other extended dMRI techniques can assess the neuronal and glial integrity of the visual system in both humans and experimental animal models of glaucoma, among other optic neuropathies or neurodegenerative diseases. We also compare the pros and cons of these methods against other imaging modalities. A growing body of dMRI research indicates that this modality holds promise in characterizing early glaucomatous changes in the visual system, determining the disease severity, and identifying potential neurotherapeutic targets, offering more options to slow glaucoma progression and to reduce the prevalence of this world's leading cause of irreversible but preventable blindness.
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Affiliation(s)
- Monica Mendoza
- Department of Biomedical Engineering, Tandon School of Engineering, New York University, New York, NY 11201, USA; (M.M.); (M.S.)
| | - Max Shotbolt
- Department of Biomedical Engineering, Tandon School of Engineering, New York University, New York, NY 11201, USA; (M.M.); (M.S.)
| | - Muneeb A. Faiq
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, NY 10017, USA; (M.A.F.); (C.P.)
| | - Carlos Parra
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, NY 10017, USA; (M.A.F.); (C.P.)
| | - Kevin C. Chan
- Department of Biomedical Engineering, Tandon School of Engineering, New York University, New York, NY 11201, USA; (M.M.); (M.S.)
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, NY 10017, USA; (M.A.F.); (C.P.)
- Department of Radiology, Neuroscience Institute, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, NY 10016, USA
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8
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Pang Y, Tan Z, Mo W, Chen X, Wei J, Guo Q, Zhong Q, Zhong J. A pilot study of combined optical coherence tomography and diffusion tensor imaging method for evaluating microstructural change in the visual pathway of pituitary adenoma patients. BMC Ophthalmol 2022; 22:115. [PMID: 35279128 PMCID: PMC8917617 DOI: 10.1186/s12886-022-02320-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Accepted: 02/19/2022] [Indexed: 02/06/2023] Open
Abstract
Background RNFL thickness measured by optical coherence tomography (OCT) and visual pathway measured by diffusion tensor imaging (DTI) can be used to predict visual field recovery, respectively. However, the relationship between RNFL thickness and visual pathway injury in patients with pituitary adenoma (PA) remains unclear. This study aims to evaluate the combining DTI and OCT methods in observing the microstructural change in the visual pathway in patients with PA. Methods Twenty-nine patients who were diagnosed with PA were included in the study group, and 29 healthy subjects were included as the control group. OCT detected the thickness of circumpapillary retinal nerve fiber layer (CP-RNFL) and ganglion cell layer (GCL). DTI measured the values of fractional anisotropy (FA) and apparent diffusion coefficient (ADC). Correlation between CP-RNFL and GCL thickness and FA and ADC values was analyzed in the study group. Results Compared with the control group, the FA values of the bilateral optic nerve, chiasma, bilateral optic tract, and left optic radiation in the study group were reduced, and the ADC values of the bilateral optic nerve and optic chiasma were increased. Correlation analysis showed that the FA value of the optic chiasma was positively correlated with the average thickness of RNFL, the CP-RNFL thickness in the nasal and temporal retinal quadrants in both eyes, as well as the thickness of macular ring GCL in the nasal, supra, and inferior quadrants. The FA values of the optic nerve, optic chiasma, optic tract, and optic radiation were positively correlated with CP-RNFL thickness in the nasal and temporal quadrants. Conclusion Combined DTI and OCT can provide a comprehensive understanding of the microscopic changes in the structure and function of the whole visual pathway in patients with PA.
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9
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Transneuronal Degeneration in the Visual Pathway of Rats following Acute Retinal Ischemia/Reperfusion. DISEASE MARKERS 2021; 2021:2629150. [PMID: 34917198 PMCID: PMC8670974 DOI: 10.1155/2021/2629150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 11/08/2021] [Indexed: 11/17/2022]
Abstract
The maintenance of visual function not only requires the normal structure and function of neurons but also depends on the effective signal propagation of synapses in visual pathways. Synapses emerge alterations of plasticity in the early stages of neuronal damage and affect signal transmission, which leads to transneuronal degeneration. In the present study, rat model of acute retinal ischemia/reperfusion (RI/R) was established to observe the morphological changes of neuronal soma and synapses in the inner plexiform layer (IPL), outer plexiform layer (OPL), and dorsal lateral geniculate nucleus (dLGN) after retinal injury. We found transneuronal degeneration in the visual pathways following RI/R concretely presented as edema and mitochondrial hyperplasia of neuronal soma in retina, demyelination, and heterotypic protein clusters of axons in LGN. Meanwhile, small immature synapses formed, and there are asynchronous changes between pre- and postsynaptic components in synapses. This evidence demonstrated that transneuronal degeneration exists in RI/R injury, which may be one of the key reasons for the progressive deterioration of visual function after the injury is removed.
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10
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Colbert MK, Ho LC, van der Merwe Y, Yang X, McLellan GJ, Hurley SA, Field AS, Yun H, Du Y, Conner IP, Parra C, Faiq MA, Fingert JH, Wollstein G, Schuman JS, Chan KC. Diffusion Tensor Imaging of Visual Pathway Abnormalities in Five Glaucoma Animal Models. Invest Ophthalmol Vis Sci 2021; 62:21. [PMID: 34410298 PMCID: PMC8383913 DOI: 10.1167/iovs.62.10.21] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Purpose To characterize the visual pathway integrity of five glaucoma animal models using diffusion tensor imaging (DTI). Methods Two experimentally induced and three genetically determined models of glaucoma were evaluated. For inducible models, chronic IOP elevation was achieved via intracameral injection of microbeads or laser photocoagulation of the trabecular meshwork in adult rodent eyes. For genetic models, the DBA/2J mouse model of pigmentary glaucoma, the LTBP2 mutant feline model of congenital glaucoma, and the transgenic TBK1 mouse model of normotensive glaucoma were compared with their respective genetically matched healthy controls. DTI parameters, including fractional anisotropy, axial diffusivity, and radial diffusivity, were evaluated along the optic nerve and optic tract. Results Significantly elevated IOP relative to controls was observed in each animal model except for the transgenic TBK1 mice. Significantly lower fractional anisotropy and higher radial diffusivity were observed along the visual pathways of the microbead- and laser-induced rodent models, the DBA/2J mice, and the LTBP2-mutant cats compared with their respective healthy controls. The DBA/2J mice also exhibited lower axial diffusivity, which was not observed in the other models examined. No apparent DTI change was observed in the transgenic TBK1 mice compared with controls. Conclusions Chronic IOP elevation was accompanied by decreased fractional anisotropy and increased radial diffusivity along the optic nerve or optic tract, suggestive of disrupted microstructural integrity in both inducible and genetic glaucoma animal models. The effects on axial diffusivity differed between models, indicating that this DTI metric may represent different aspects of pathological changes over time and with severity.
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Affiliation(s)
- Max K Colbert
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, United States
| | - Leon C Ho
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Yolandi van der Merwe
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Xiaoling Yang
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Gillian J McLellan
- Department of Ophthalmology and Visual Sciences, University of Wisconsin - Madison, Madison, Wisconsin, United States.,McPherson Eye Research Institute, University of Wisconsin - Madison, Madison, Wisconsin, United States
| | - Samuel A Hurley
- Department of Radiology, University of Wisconsin - Madison, Madison, Wisconsin, United States
| | - Aaron S Field
- Department of Radiology, University of Wisconsin - Madison, Madison, Wisconsin, United States
| | - Hongmin Yun
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Yiqin Du
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Ian P Conner
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Carlos Parra
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, United States
| | - Muneeb A Faiq
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, United States
| | - John H Fingert
- Department of Ophthalmology and Visual Sciences, University of Iowa College of Medicine, Iowa City, Iowa, United States
| | - Gadi Wollstein
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, United States.,Center for Neural Science, College of Arts and Science, New York University, New York, New York, United States.,Department of Biomedical Engineering, New York University Tandon School of Engineering, Brooklyn, New York, United States
| | - Joel S Schuman
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, United States.,Center for Neural Science, College of Arts and Science, New York University, New York, New York, United States.,Department of Biomedical Engineering, New York University Tandon School of Engineering, Brooklyn, New York, United States.,Neuroscience Institute, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, United States
| | - Kevin C Chan
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, United States.,Center for Neural Science, College of Arts and Science, New York University, New York, New York, United States.,Department of Biomedical Engineering, New York University Tandon School of Engineering, Brooklyn, New York, United States.,Neuroscience Institute, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, United States.,Department of Radiology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, United States
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11
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Trans-synaptic degeneration in the visual pathway: Neural connectivity, pathophysiology, and clinical implications in neurodegenerative disorders. Surv Ophthalmol 2021; 67:411-426. [PMID: 34146577 DOI: 10.1016/j.survophthal.2021.06.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 06/06/2021] [Accepted: 06/07/2021] [Indexed: 12/13/2022]
Abstract
There is a strong interrelationship between eye and brain diseases. It has been shown that neurodegenerative changes can spread bidirectionally in the visual pathway along neuronal projections. For example, damage to retinal ganglion cells in the retina leads to degeneration of the visual cortex (anterograde degeneration) and vice versa (retrograde degeneration). The underlying mechanisms of this process, known as trans-synaptic degeneration (TSD), are unknown, but TSD contributes to the progression of numerous neurodegenerative disorders, leading to clinical and functional deterioration. The hierarchical structure of the visual system comprises of a strong topographic connectivity between the retina and the visual cortex and therefore serves as an ideal model to study the cellular effect, clinical manifestations, and deterioration extent of TSD. With this review we provide comprehensive information about the neural connectivity, synapse function, molecular changes, and pathophysiology of TSD in visual pathways. We then discuss its bidirectional nature and clinical implications in neurodegenerative diseases. A thorough understanding of TSD in the visual pathway can provide insights into progression of neurodegenerative disorders and its potential as a therapeutic target.
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12
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Nuzzi R, Vitale A. Cerebral Modifications in Glaucoma and Macular Degeneration: Analysis of Current Evidence in Literature and Their Implications on Therapeutic Perspectives. Eye Brain 2021; 13:159-173. [PMID: 34168513 PMCID: PMC8216745 DOI: 10.2147/eb.s307551] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 04/14/2021] [Indexed: 01/19/2023] Open
Abstract
Glaucoma and macular degeneration are leading causes of irreversible blindness, significantly compromising the quality of life and having a high economic and social impact. Promising therapeutic approaches aimed at regenerating or bypassing the damaged anatomical-functional components are currently under development: these approaches have generated great expectations, but to be effective require a visual network that, despite the pathology, maintains its integrity up to the higher brain areas. In the light of this, the existing findings concerning how the central nervous system modifies its connections following the pathological damage caused by glaucoma and macular degeneration acquire great interest. This review aims to examine the scientific literature concerning the morphological and functional changes affecting the central nervous system in these pathological conditions, summarizing the evidence in an analytical way, discussing their possible causes and highlighting the potential repercussions on the current therapeutic perspectives.
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Affiliation(s)
- Raffaele Nuzzi
- Eye Clinic, Department of Surgical Sciences, University of Turin, Turin, 10126, Italy
| | - Alessio Vitale
- Eye Clinic, Department of Surgical Sciences, University of Turin, Turin, 10126, Italy
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Takahashi N, Matsunaga N, Natsume T, Kitazawa C, Itani Y, Hama A, Hayashi I, Shimazawa M, Hara H, Takamatsu H. A longitudinal comparison in cynomolgus macaques of the effect of brimonidine on optic nerve neuropathy using diffusion tensor imaging magnetic resonance imaging and spectral domain optical coherence tomography. Heliyon 2021; 7:e06701. [PMID: 33898826 PMCID: PMC8056221 DOI: 10.1016/j.heliyon.2021.e06701] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 01/04/2021] [Accepted: 03/31/2021] [Indexed: 10/26/2022] Open
Abstract
Early detection of optic neuropathy is crucial for initiating treatment that could delay or prevent visual field loss. Preclinical studies have advanced a number of potential neuroprotective strategies to prevent retinal ganglion cell (RGC) degeneration, but none have successfully completed clinical trials. One issue related to the lack of preclinical to clinical translation is the lack of preclinical morphometric assessments that could be used to track neuroprotection, as well as neurodegeneration, over time within the same animal. Thus, to assess whether clinically used morphometric assessments can identify neuroprotection of RGC, the current study compared optic nerve fractional anisotropy (FA) obtained with diffusion tensor imaging (DTI) and retinal nerve fiber layer (RNFL) thickness measured with spectral domain optical coherence tomography (SD-OCT) to observe not only the early progression of RGC axonal degeneration but to also discern which imaging modality identifies signs of neuroprotection during treatment with the alpha-adrenoceptor agonist brimonidine. Elevated and sustained intraocular pressure (IOP) was observed following laser photocoagulation of the trabecular meshwork in one eye of nonhuman primates (NHP). Either brimonidine (0.1%) or control treatment was instilled twice daily for two months. In control-treated eyes, increased IOP, increased vertical cup-to-disc (C/D), reduced rim-to-disc (R/D) ratio, decreased RNFL thickness and decreased FA were observed. While IOP remained elevated during the course of the study, brimonidine tended to delay the progression of RNFL thinning. However, in the same animal, optic nerve FA did not appear to decline. Brimonidine treatment did not affect other measures of RGC axonal degeneration. The current findings demonstrate that early progression of optic neuropathy can be tracked over time in a nonhuman primate model of ocular hypertension using either DTI or SD-OCT. Furthermore, the delayed changes to RNFL thickness and FA appear to be a neuroprotective effect of brimonidine independent of its effect on IOP.
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Affiliation(s)
- Nobuyuki Takahashi
- Pharmacology, Hamamatsu Pharma Research, Inc., 1-3-7, Shinmiyakoda, Kita-ku, Hamamatsu, Shizuoka, 431-2103, Japan
| | - Naoko Matsunaga
- Pharmacology, Hamamatsu Pharma Research, Inc., 1-3-7, Shinmiyakoda, Kita-ku, Hamamatsu, Shizuoka, 431-2103, Japan
| | - Takahiro Natsume
- Pharmacology, Hamamatsu Pharma Research, Inc., 1-3-7, Shinmiyakoda, Kita-ku, Hamamatsu, Shizuoka, 431-2103, Japan
| | - Chinatsu Kitazawa
- Pharmacology, Hamamatsu Pharma Research, Inc., 1-3-7, Shinmiyakoda, Kita-ku, Hamamatsu, Shizuoka, 431-2103, Japan
| | - Yoshitaka Itani
- Pharmacology, Hamamatsu Pharma Research, Inc., 1-3-7, Shinmiyakoda, Kita-ku, Hamamatsu, Shizuoka, 431-2103, Japan
| | - Aldric Hama
- Pharmacology, Hamamatsu Pharma Research, Inc., 1-3-7, Shinmiyakoda, Kita-ku, Hamamatsu, Shizuoka, 431-2103, Japan
| | - Ikuo Hayashi
- Hamamatsu Pharma Research USA, Inc., 4660 La Jolla Village Drive, San Diego, CA, 92122 USA
| | - Masamitsu Shimazawa
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan
| | - Hideaki Hara
- Molecular Pharmacology, Department of Biofunctional Evaluation, Gifu Pharmaceutical University, 1-25-4 Daigaku-nishi, Gifu 501-1196, Japan
| | - Hiroyuki Takamatsu
- Pharmacology, Hamamatsu Pharma Research, Inc., 1-3-7, Shinmiyakoda, Kita-ku, Hamamatsu, Shizuoka, 431-2103, Japan
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14
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Haykal S, Jansonius NM, Cornelissen FW. Progression of Visual Pathway Degeneration in Primary Open-Angle Glaucoma: A Longitudinal Study. Front Hum Neurosci 2021; 15:630898. [PMID: 33854423 PMCID: PMC8039117 DOI: 10.3389/fnhum.2021.630898] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 03/05/2021] [Indexed: 11/18/2022] Open
Abstract
Background: Primary open-angle glaucoma (POAG) patients exhibit widespread white matter (WM) degeneration throughout their visual pathways. Whether this degeneration starts at the pre- or post-geniculate pathways remains unclear. In this longitudinal study, we assess the progression of WM degeneration exhibited by the pre-geniculate optic tracts (OTs) and the post-geniculate optic radiations (ORs) of POAG patients over time, aiming to determine the source and pattern of spread of this degeneration. Methods: Diffusion-weighted MRI scans were acquired for 12 POAG patients and 14 controls at two time-points 5.4 ± 2.1 years apart. Fiber density (FD), an estimate of WM axonal density, was computed for the OTs and ORs of all participants in an unbiased longitudinal population template space. First, FD was compared between POAG patients and the controls at time-point 1 (TP1) and time-point 2 (TP2) independently. Secondly, repeated measures analysis was performed for FD change in POAG patients between the two time-points. Finally, we compared the rate of FD change over time between the two groups. Results: Compared to the controls, POAG patients exhibited significantly lower FD in the left OT at TP1 and in both OTs and the left OR at TP2. POAG patients showed a significant loss of FD between the time-points in the right OT and both ORs, while the left OR showed a significantly higher rate of FD loss in POAG patients compared to the controls. Conclusions: We find longitudinal progression of neurodegenerative WM changes in both the pre- and post-geniculate visual pathways of POAG patients. The pattern of changes suggests that glaucomatous WM degeneration starts at the pre-geniculate pathways and then spreads to the post-geniculate pathways. Furthermore, we find evidence that the trans-synaptic spread of glaucomatous degeneration to the post-geniculate pathways is a prolonged process which continues in the absence of detectable pre-geniculate degenerative progression. This suggests the presence of a time window for salvaging intact post-geniculate pathways, which could prove to be a viable therapeutic target in the future.
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Affiliation(s)
- Shereif Haykal
- Laboratory for Experimental Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Nomdo M Jansonius
- Department of Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Frans W Cornelissen
- Laboratory for Experimental Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
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15
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Chow LS, Paley MNJ. Recent advances on optic nerve magnetic resonance imaging and post-processing. Magn Reson Imaging 2021; 79:76-84. [PMID: 33753137 DOI: 10.1016/j.mri.2021.03.014] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 03/17/2021] [Accepted: 03/17/2021] [Indexed: 11/27/2022]
Abstract
The optic nerve is known to be one of the largest nerve bundles in the human central nervous system. There have been many studies of optic nerve imaging and post-processing that have provided insights into pathophysiology of optic neuritis related to multiple sclerosis and neuromyelitis optica spectrum disorder, glaucoma, and Leber's hereditary optic neuropathy. There are many challenges in optic nerve imaging, due to the morphology of the nerve through its course to the optic chiasm, its mobility due to eye movements and the high signal from cerebrospinal fluid and orbital fat surrounding the optic nerve. Recently, many advanced and fast imaging sequences have been used with post-processing techniques in attempts to produce higher resolution images of the optic nerve for evaluating various diseases. Magnetic resonance imaging (MRI) is one of the most common imaging methodologies for the optic nerve. This review paper will focus on recent MRI advances in optic nerve imaging and explain several post-processing techniques being used for analysis of optic nerve images. Finally, some challenges and potential for future optic nerve studies will be discussed.
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Affiliation(s)
- Li Sze Chow
- Department of Electrical and Electronic Engineering, Faculty of Engineering and Built Environment, UCSI University, 1, Jalan Puncak Menara Gading, Taman Connaught, 56000 Cheras, Kuala Lumpur, Malaysia.
| | - Martyn N J Paley
- Department of Infection, Immunity and Cardiovascular Disease, The Medical School, The University of Sheffield, Beech Hill Road, Sheffield S10 2RX, UK.
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16
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Haykal S, Jansonius NM, Cornelissen FW. Investigating changes in axonal density and morphology of glaucomatous optic nerves using fixel-based analysis. Eur J Radiol 2020; 133:109356. [DOI: 10.1016/j.ejrad.2020.109356] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 09/18/2020] [Accepted: 10/11/2020] [Indexed: 12/13/2022]
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17
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Abstract
Glaucoma is a chronic progressive optic neuropathy that causes irreversible loss of visual functions. From the clinical point of view, normal-tension glaucoma (NTG) is regarded in Russian taxonomy as a clinical form of standard primary open-angle glaucoma in which the IOP values stay within the normal range, but the typical progressive visual functions loss is still present. The results of the latest studies put in question the traditional views of NTG pathophysiology that are based solely on intraocular pressure values. New capabilities of diagnostic visualization of central nervous system have considerably broadened our knowledge of the NTG development mechanisms. This article reviews current understanding of the pathogenesis of NTG and its connection to vascular and immune factors, translaminar pressure difference etc. The review also considers the relationship between glaucoma and cognitive defects associated with Alzheimer's and Parkinson's diseases.
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Affiliation(s)
- S Yu Petrov
- Research Institute of Eye Diseases, Moscow, Russia
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18
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Graham KL, Johnson PJ, Barry EF, Pérez Orrico M, Soligo DJ, Lawlor M, White A. Diffusion tensor imaging of the visual pathway in dogs with primary angle-closure glaucoma. Vet Ophthalmol 2020; 24 Suppl 1:63-74. [PMID: 32990378 DOI: 10.1111/vop.12824] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 08/09/2020] [Accepted: 08/14/2020] [Indexed: 12/13/2022]
Abstract
OBJECTIVE To describe measurements of in vivo structures of the visual pathway beyond the retina and optic nerve head associated with canine primary angle-closure glaucoma (PACG). METHODS A prospective pilot study was conducted using magnetic resonance diffusion tensor imaging (DTI) to obtain quantitative measures of the optic nerve, chiasm, tract, and lateral geniculate nucleus (LGN) in dogs with and without PACG. 3-Tesla DTI was performed on six affected dogs and five breed, age- and sex-matched controls. DTI indices of the optic nerve, optic chiasm, optic tracts, and LGN were compared between normal, unilateral PACG, and bilateral PACG groups. Intra-class correlation coefficient (ICC) was calculated to assess intra-observer reliability. RESULTS Quantitative measurements of the optic nerve, optic tract, optic chiasm, and LGN were obtained in all dogs. There was a trend for reduced fractional anisotropy (FA) associated with disease for all structures assessed. Compared to the same structure in normal dogs, FA, and radial diffusivity (RD) of the optic nerve was consistently higher in the unaffected eye in dogs with unilateral PACG. Intra-observer reliability was excellent for measurements of the optic nerve (ICC: 0.92), good for measurements of the optic tract (ICC: 0.89) and acceptable for measures of the optic chiasm (ICC: 0.71) and lateral geniculate nuclei (ICC: 0.76). CONCLUSION Diffusivity and anisotropy measures provide a quantifiable means to evaluate the visual pathway in dogs. DTI has potential to provide in vivo measures of axonal and myelin injury and transsynaptic degeneration in canine PACG.
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Affiliation(s)
- Kathleen L Graham
- Clinical Ophthalmology and Eye Health, University of Sydney, Sydney, NSW, Australia
| | | | - Erica F Barry
- Cornell College of Veterinary Medicine, Ithaca, NY, USA
| | | | | | - Mitchell Lawlor
- Clinical Ophthalmology and Eye Health, University of Sydney, Sydney, NSW, Australia
| | - Andrew White
- Clinical Ophthalmology and Eye Health, University of Sydney, Sydney, NSW, Australia.,Westmead Institute for Medical Research, Westmead, NSW, Australia
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19
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Cheng Y, Huang X, Hu YX, Huang MH, Yang B, Zhou FQ, Wu XR. Comparison of intrinsic brain activity in individuals with low/moderate myopia versus high myopia revealed by the amplitude of low-frequency fluctuations. Acta Radiol 2020; 61:496-507. [PMID: 31398992 DOI: 10.1177/0284185119867633] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Background Previous neuroimaging studies demonstrated that individuals with high myopia are associated with abnormalities in anatomy of the brain. Purpose The purpose of this study was to explore alterations in the intrinsic brain activity by studying the amplitude of low-frequency fluctuations. Material and Methods A total of 64 myopia individuals (41 with high myopia with a refractive error <–600 diopter [D], 23 with low/moderate myopia with a refractive error between –100 and –600 D, and similarly 59 healthy controls with emmetropia closely matched for age) were recruited. The amplitude of low-frequency fluctuations method was conducted to investigate the difference of intrinsic brain activity across three groups. Results Compared with the healthy controls, individuals with low/moderate myopia showed significantly decreased amplitude of low-frequency fluctuation values in the bilateral rectal gyrus, right cerebellum anterior lobe/calcarine, and bilateral thalamus and showed significantly increased amplitude of low-frequency fluctuation values in left white matter (optic radiation), right prefrontal cortex, and left primary motor cortex (M1)/primary somatosensory cortex (S1). In addition, individuals with high myopia showed significantly decreased amplitude of low-frequency fluctuation values in the right cerebellum anterior lobe/calcarine/bilateral parahippocampal gyrus, bilateral posterior cingulate cortex, and bilateral middle cingulate cortex and significantly increased amplitude of low-frequency fluctuation values in left white matter (optic radiation), bilateral frontal parietal cortex, and left M1/S1. Moreover, we found that the amplitude of low-frequency fluctuation values of the different brain areas was closely related to the clinical features in the high myopia group. Conclusion Our results demonstrated that individuals with low/moderate myopia and high myopia had abnormal intrinsic brain activities in various brain regions related to the limbic system, default mode network, and thalamo-occipital pathway.
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Affiliation(s)
- Yi Cheng
- Department of Ophthalmology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi Province, PR China
| | - Xin Huang
- Department of Ophthalmology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi Province, PR China
| | - Yu-Xiang Hu
- Department of Ophthalmology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi Province, PR China
| | - Mu-Hua Huang
- Department of Radiology, The First Affiliated Hospital of Nanchang University, Jiangxi Province Medical Imaging Research Institute, Nanchang, Jiangxi Province, PR China
- Jiangxi Province Medical Imaging Research Institute, Nanchang, Jiangxi Province, PR China
| | - Bo Yang
- Department of Ophthalmology, The People’s Hospital of Xinjiang, Urumqi, PR China
| | - Fu-Qing Zhou
- Department of Radiology, The First Affiliated Hospital of Nanchang University, Jiangxi Province Medical Imaging Research Institute, Nanchang, Jiangxi Province, PR China
- Jiangxi Province Medical Imaging Research Institute, Nanchang, Jiangxi Province, PR China
| | - Xiao-Rong Wu
- Department of Ophthalmology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi Province, PR China
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20
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Haykal S, Curcic-Blake B, Jansonius NM, Cornelissen FW. Fixel-Based Analysis of Visual Pathway White Matter in Primary Open-Angle Glaucoma. ACTA ACUST UNITED AC 2019; 60:3803-3812. [DOI: 10.1167/iovs.19-27447] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Shereif Haykal
- Laboratory for Experimental Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Branislava Curcic-Blake
- Department of Biomedical Sciences of Cells & Systems, University Medical Center Groningen, Groningen, The Netherlands
| | - Nomdo M. Jansonius
- Department of Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Frans W. Cornelissen
- Laboratory for Experimental Ophthalmology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
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21
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Wu CN, Duan SF, Mu XT, Wang Y, Lan PY, Wang XL, Li KC. Assessment of optic nerve and optic tract alterations in patients with orbital space-occupying lesions using probabilistic diffusion tractography. Int J Ophthalmol 2019; 12:1304-1310. [PMID: 31456921 DOI: 10.18240/ijo.2019.08.11] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 05/15/2019] [Indexed: 12/29/2022] Open
Abstract
AIM To investigate the diffusion changes in both the optic nerve and optic tract in orbital space-occupying lesion patients with decreased visual acuity, and its clinical significance using probabilistic diffusion tractography (PDT). METHODS Twenty patients with orbital space-occupying lesions and 25 age- and gender-matched healthy persons were included. All patients and controls underwent routine orbital magnetic resonance imaging and diffusion tensor imaging (DTI), using a 3.0T magnetic resonance scanner (Trio Tim Siemens). After the image data were preprocessed, each DTI parameters of the optic nerve and optic tract was obtained by PDT, including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD). The asymmetry index (AI) of each parameter was calculated. Compared the parameters of the affected side optic nerve and ipsilateral optic tract with the contralateral side by paired sample t-test; compared AI of parameters of optic nerve and optic tract between the patient group and the control group by independent sample t-test. Patients were divided into three subgroups according to the low vision grade standard of WHO, compared the FA and AI of FA between the three subgroups by single factor variance analysis. RESULTS The affected side optic nerve presented significantly decreased FA, increased MD, AD, and RD values compared to the unaffected side (P<0.05). The AI of FA, MD, AD, and RD of optic nerve in the patients was significantly higher than that of the controls (P<0.05). The comparison results of the optic tract showed that there was no significant difference between the patient group and control group in terms of the bilateral optic tracts in patients (P>0.05). The AIs of the FA value of the optic nerve in the eyesight <0.1 subgroup was significantly higher than that in the other groups (P<0.05). CONCLUSION FA, MD, AD, and RD of the affected side optic nerve of the orbital space-occupying lesions have significantly changed, the FA value is the most sensitive. The PDT could be a useful tool to provide valid quantitative markers of optic nerve injuries and evaluate the severity of orbital diseases, which other examinations cannot be acquired.
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Affiliation(s)
- Chun-Nan Wu
- Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053, China.,Department of Radiology, the Third Medical Center of Chinese PLA General Hospital, Beijing 100039, China
| | - Shao-Feng Duan
- Division of Nuclear Technology and Applications, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.,Beijing Engineering Research Center of Radiographic Techniques and Equipment, Beijing 100049, China
| | - Xue-Tao Mu
- Department of Radiology, the Third Medical Center of Chinese PLA General Hospital, Beijing 100039, China
| | - Yi Wang
- Orbital Disease Institute, the Third Medical Center of Chinese PLA General Hospital, Beijing 100039, China
| | - Peng-Yu Lan
- Department of Radiology, the Third Medical Center of Chinese PLA General Hospital, Beijing 100039, China
| | - Xiao-Lu Wang
- Department of Otolaryngology, the Third Medical Center of Chinese PLA General Hospital, Beijing 100039, China
| | - Kun-Cheng Li
- Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
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22
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Miller N, Liu Y, Krivochenitser R, Rokers B. Linking neural and clinical measures of glaucoma with diffusion magnetic resonance imaging (dMRI). PLoS One 2019; 14:e0217011. [PMID: 31150402 PMCID: PMC6544345 DOI: 10.1371/journal.pone.0217011] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Accepted: 05/02/2019] [Indexed: 01/25/2023] Open
Abstract
Purpose To link optic nerve (ON) structural properties to clinical markers of glaucoma using advanced, semi-automated diffusion magnetic resonance imaging (dMRI) tractography in human glaucoma patients. Methods We characterized optic neuropathy in patients with unilateral advanced-stage glaucoma (n = 6) using probabilistic dMRI tractography and compared their results to those in healthy controls (n = 6). Results We successfully identified the ONs of glaucoma patients based on dMRI in all patients and confirmed that dMRI measures of the ONs correlated with clinical markers of glaucoma severity. Specifically, we found reduced fractional anisotropy (FA) in the ONs of eyes with advanced, as compared to mild, glaucoma (F(1,10) = 55.474, p < 0.0001, FDR < 0.0005). Furthermore, by comparing the ratios of ON FA in glaucoma patients to those of healthy controls (n = 6), we determined that this difference was beyond that expected from normal anatomical variation (F(1,9) = 20.276, p < 0. 005). Finally, we linked the dMRI measures of ON FA to standard clinical glaucoma measures. ON vertical cup-to-disc ratio (vCD) predicted ON FA (F(1,10) = 11.061, p < 0.01, R2 = 0.66), retinal nerve fiber layer thickness (RNFL) predicted ON FA (F(1,10) = 11.477, p < 0.01, R2 = 0.63) and ON FA predicted perceptual deficits (visual field index [VFI]) (F(1,10) = 15.308, p < 0.005, R2 = 0.52). Conclusion We describe semi-automated methods to detect glaucoma-related structural changes using dMRI and confirm that they correlate with clinical measures of glaucoma.
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Affiliation(s)
- Nathaniel Miller
- Department of Psychology, University of Wisconsin – Madison, Madison, Wisconsin, United States of America
| | - Yao Liu
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, United States of America
- McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, United States of America
| | - Roman Krivochenitser
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, United States of America
| | - Bas Rokers
- Department of Psychology, University of Wisconsin – Madison, Madison, Wisconsin, United States of America
- McPherson Eye Research Institute, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, United States of America
- * E-mail:
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23
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Qu X, Wang Q, Chen W, Li T, Guo J, Wang H, Zhang X, Wang Y, Wang N, Xian J. Combined machine learning and diffusion tensor imaging reveals altered anatomic fiber connectivity of the brain in primary open-angle glaucoma. Brain Res 2019; 1718:83-90. [PMID: 31071304 DOI: 10.1016/j.brainres.2019.05.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Revised: 05/04/2019] [Accepted: 05/05/2019] [Indexed: 11/26/2022]
Abstract
Parameters derived from diffusion tensor imaging (DTI) have been found to be significantly altered in the optic tracts, optic nerves, and optic radiations in patients with primary open-angle glaucoma (POAG). In this study, DTI-derived parameters were further constructed into fiber connectivity, and we investigated anatomical fiber connectivity changes within and beyond the visual pathway in POAG patients. DTI and T1-weighted magnetic resonance images were acquired in 18 POAG patients and 26 healthy controls (HC). White matter tracts based on the Brodmann atlases (BA) were constructed using the deterministic fiber tracking method. The mean fractional anisotropy (FA), fiber number (FN), and mean fiber length (FL) were measured and then evaluated using two-sample t-tests between POAG and HC. The fiber connectivity between regions was taken as the features for classifying HC and POAG using a machine learning method known as naïve Bayesian classification. The mean FA decreased in connections between visual cortex BA17/BA18 and cortex BA23/BA25/BA35/BA36, while it increased in the connections between cortex BA3/BA7/BA9 and BA5/BA6/BA45/BA25 in POAG. Classification using fibers where a significant difference in FN had been identified produced better accuracy (ACC = 0.89) than using FA or FL (ACC = 0.77 and 0.75, respectively). The FN of individual fiber connections with higher accuracy and significant changes in POAG involved brain regions associated with vision (BA19), depression (BA10/BA46/BA25), and memory (BA29). These findings strengthen the hypothesis that POAG involves changes in anatomical connectivity within and beyond the visual pathway. Classification using the machine learning method reveals that mean FN has the potential to be used as a biomarker for detecting white matter microstructure changes in POAG.
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Affiliation(s)
- Xiaoxia Qu
- Department of Radiology, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Qian Wang
- Department of Radiology, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Weiwei Chen
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing Tongren Hospital, Capital Medical University, China
| | - Ting Li
- Department of Radiology, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Jian Guo
- Department of Radiology, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Huaizhou Wang
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing Tongren Hospital, Capital Medical University, China
| | - Xun Zhang
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing Tongren Hospital, Capital Medical University, China
| | - Ying Wang
- Department of Radiology, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Ningli Wang
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing Tongren Hospital, Capital Medical University, China.
| | - Junfang Xian
- Department of Radiology, Beijing Tongren Hospital, Capital Medical University, Beijing, China.
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24
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Hofstetter S, Sabbah N, Mohand-Saïd S, Sahel JA, Habas C, Safran AB, Amedi A. The development of white matter structural changes during the process of deterioration of the visual field. Sci Rep 2019; 9:2085. [PMID: 30765782 PMCID: PMC6375971 DOI: 10.1038/s41598-018-38430-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 12/27/2018] [Indexed: 12/02/2022] Open
Abstract
Emerging evidence suggests that white matter plasticity in the adult brain is preserved after sensory and behavioral modifications. However, little is known about the progression of structural changes during the process of decline in visual input. Here we studied two groups of patients suffering from advanced retinitis pigmentosa with specific deterioration of the visual field: patients who had lost their peripheral visual field, retaining only central (“tunnel”) vision, and blind patients with complete visual field loss. Testing of these homogeneous groups made it possible to assess the extent to which the white matter is affected by loss of partial visual input and whether partially preserved visual input suffices to sustain stability in tracts beyond the primary visual system. Our results showed gradual changes in diffusivity that are indicative of degenerative processes in the primary visual pathway comprising the optic tract and the optic radiation. Interestingly, changes were also found in tracts of the ventral stream and the corticospinal fasciculus, depicting a gradual reorganisation of these tracts consequentially to the gradual loss of visual field coverage (from intact perception to partial vision to complete blindness). This reorganisation may point to microstructural plasticity underlying adaptive behavior and cross-modal integration after partial visual deprivation.
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Affiliation(s)
- Shir Hofstetter
- Department of Medical Neurobiology, The Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, 91220, Jerusalem, Israel. .,The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, 91220, Jerusalem, Israel.
| | - Norman Sabbah
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France
| | - Saddek Mohand-Saïd
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, F-75012, Paris, France
| | - José-Alain Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, F-75012, Paris, France.,Fondation Ophtalmologique A. de Rothschild, F-75019, Paris, France.,Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA
| | - Christophe Habas
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, F-75012, Paris, France.,Centre de Neuro-Imagerie, Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, Paris, F-75012, France
| | - Avinoam B Safran
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DGOS CIC 1423, F-75012, Paris, France.,Department of Clinical Neurosciences, Geneva University School of Medicine, Geneva, Switzerland
| | - Amir Amedi
- Department of Medical Neurobiology, The Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, 91220, Jerusalem, Israel. .,The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, 91220, Jerusalem, Israel. .,Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France. .,The Cognitive Science Program, The Hebrew University of Jerusalem, 91220, Jerusalem, Israel.
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25
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You Y, Joseph C, Wang C, Gupta V, Liu S, Yiannikas C, Chua BE, Chitranshi N, Shen T, Dheer Y, Invernizzi A, Borotkanics R, Barnett M, Graham SL, Klistorner A. Demyelination precedes axonal loss in the transneuronal spread of human neurodegenerative disease. Brain 2019; 142:426-442. [DOI: 10.1093/brain/awy338] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 11/20/2018] [Indexed: 11/12/2022] Open
Affiliation(s)
- Yuyi You
- Save Sight Institute, Sydney Medical School, The University of Sydney, Sydney, Australia
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, Macquarie University, Sydney, Australia
| | - Chitra Joseph
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, Macquarie University, Sydney, Australia
| | - Chenyu Wang
- Brain and Mind Centre, Sydney Medical School, The University of Sydney, Sydney, Australia
- Sydney Neuroimaging Analysis Centre, Sydney, Australia
| | - Vivek Gupta
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, Macquarie University, Sydney, Australia
| | - Sidong Liu
- Save Sight Institute, Sydney Medical School, The University of Sydney, Sydney, Australia
- Brain and Mind Centre, Sydney Medical School, The University of Sydney, Sydney, Australia
| | - Con Yiannikas
- Department of Neurology, Royal North Shore Hospital, Sydney, Australia
| | - Brian E Chua
- Glaucoma Unit, Sydney Eye Hospital, Sydney, Australia
| | - Nitin Chitranshi
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, Macquarie University, Sydney, Australia
| | - Ting Shen
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, Macquarie University, Sydney, Australia
| | - Yogita Dheer
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, Macquarie University, Sydney, Australia
| | - Alessandro Invernizzi
- Save Sight Institute, Sydney Medical School, The University of Sydney, Sydney, Australia
- Eye Clinic, Department of Biomedical and Clinical Science ‘L. Sacco’, Luigi Sacco Hospital, University of Milan, Milan, Italy
| | - Robert Borotkanics
- Applied Biostatistics, Johns Hopkins Bloomberg School of Public Health, Johns Hopkins University, USA
- Department of Biostatistics and Epidemiology, Faculty of Medicine and Environmental Sciences, Auckland University of Technology, New Zealand
| | - Michael Barnett
- Brain and Mind Centre, Sydney Medical School, The University of Sydney, Sydney, Australia
- Sydney Neuroimaging Analysis Centre, Sydney, Australia
- Department of Neurology, Royal Prince Alfred Hospital, Sydney, Australia
| | - Stuart L Graham
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, Macquarie University, Sydney, Australia
| | - Alexander Klistorner
- Save Sight Institute, Sydney Medical School, The University of Sydney, Sydney, Australia
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, Macquarie University, Sydney, Australia
- Sydney Neuroimaging Analysis Centre, Sydney, Australia
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26
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Abstract
Glaucoma is a chronic, progressive optic neuropathy characterized by the loss of peripheral vision first and then central vision. Clinically, normal tension glaucoma is considered a special subtype of glaucoma, in which the patient's intraocular pressure is within the normal range, but the patient experiences typical glaucomatous changes. However, increasing evidence has challenged the traditional pathophysiological view of normal tension glaucoma, which is based only on intraocular pressure, and breakthroughs in central nervous system imaging may now greatly increase our knowledge about the mechanisms underlying normal tension glaucoma. In this article, we review the latest progress in understanding the pathogenesis of normal tension glaucoma and in developing imaging techniques to detect it, to strengthen the appreciation for the connection between normal tension glaucoma and the brain.
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Affiliation(s)
- Hui-Jun Zhang
- Department of Ophthalmology, the First Affiliated Hospital of Jinan University, Guangzhou, Guangdong Province, China
| | - Xue-Song Mi
- Department of Ophthalmology, the First Affiliated Hospital of Jinan University, Guangzhou, Guangdong Province, China
| | - Kwok-Fai So
- Guangdong-Hong Kong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, Guangdong Province; State Key Laboratory of Brain and Cognitive Sciences; Department of Ophthalmology, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
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27
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Li M, Ke M, Song Y, Mu K, Zhang H, Chen Z. Diagnostic utility of central damage determination in glaucoma by magnetic resonance imaging: An observational study. Exp Ther Med 2018; 17:1891-1895. [PMID: 30783465 DOI: 10.3892/etm.2018.7134] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 11/30/2018] [Indexed: 11/05/2022] Open
Abstract
The aim of the present study was to investigate the utility of diffusion tensor imaging (DTI) parameters of the central visual pathway and the size of the lateral geniculate nucleus (LGN) in the diagnosis of primary open-angle glaucoma (POAG). To test this, 24 POAG patients and 24 age- and gender-matched controls underwent 3.0 Tesla magnetic resonance imaging examinations, including DTI and LGN structural imaging. Receiver operating characteristic (ROC) curves were generated and Spearman's correlation coefficients were also determined. The results indicated that regarding the discrimination of POAG patients from healthy controls, the fractional anisotropy (FA) values of the optic tract, at a cutoff of ≤0.412, with an area under the ROC curve of 0.931, exhibited the highest sensitivity (79.2%) and specificity (89.6%). The FA values of the optic tract and the optic radiation were significantly correlated with LGN size, while the mean diffusivity values were not. In conclusion, the FA value of the optic tract may be a sensitive and reliable biomarker for glaucoma evaluation.
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Affiliation(s)
- Mu Li
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Manlin Ke
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Yinwei Song
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Ketao Mu
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Hong Zhang
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
| | - Zhiqi Chen
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China
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28
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Diffusion tensor imaging of the optic disc in idiopathic intracranial hypertension. Neuroradiology 2018; 60:1159-1166. [DOI: 10.1007/s00234-018-2078-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 08/07/2018] [Indexed: 12/11/2022]
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29
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Nuzzi R, Dallorto L, Rolle T. Changes of Visual Pathway and Brain Connectivity in Glaucoma: A Systematic Review. Front Neurosci 2018; 12:363. [PMID: 29896087 PMCID: PMC5986964 DOI: 10.3389/fnins.2018.00363] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 05/09/2018] [Indexed: 01/19/2023] Open
Abstract
Background: Glaucoma is a leading cause of irreversible blindness worldwide. The increasing interest in the involvement of the cortical visual pathway in glaucomatous patients is due to the implications in recent therapies, such as neuroprotection and neuroregeneration. Objective: In this review, we outline the current understanding of brain structural, functional, and metabolic changes detected with the modern techniques of neuroimaging in glaucomatous subjects. Methods: We screened MEDLINE, EMBASE, CINAHL, CENTRAL, LILACS, Trip Database, and NICE for original contributions published until 31 October 2017. Studies with at least six patients affected by any type of glaucoma were considered. We included studies using the following neuroimaging techniques: functional Magnetic Resonance Imaging (fMRI), resting-state fMRI (rs-fMRI), magnetic resonance spectroscopy (MRS), voxel- based Morphometry (VBM), surface-based Morphometry (SBM), diffusion tensor MRI (DTI). Results: Over a total of 1,901 studies, 56 case series with a total of 2,381 patients were included. Evidence of neurodegenerative process in glaucomatous patients was found both within and beyond the visual system. Structural alterations in visual cortex (mainly reduced cortex thickness and volume) have been demonstrated with SBM and VBM; these changes were not limited to primary visual cortex but also involved association visual areas. Other brain regions, associated with visual function, demonstrated a certain grade of increased or decreased gray matter volume. Functional and metabolic abnormalities resulted within primary visual cortex in all studies with fMRI and MRS. Studies with rs-fMRI found disrupted connectivity between the primary and higher visual cortex and between visual cortex and associative visual areas in the task-free state of glaucomatous patients. Conclusions: This review contributes to the better understanding of brain abnormalities in glaucoma. It may stimulate further speculation about brain plasticity at a later age and therapeutic strategies, such as the prevention of cortical degeneration in patients with glaucoma. Structural, functional, and metabolic neuroimaging methods provided evidence of changes throughout the visual pathway in glaucomatous patients. Other brain areas, not directly involved in the processing of visual information, also showed alterations.
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Affiliation(s)
- Raffaele Nuzzi
- Eye Clinic, Department of Surgical Sciences, University of Torino, Turin, Italy
| | - Laura Dallorto
- Eye Clinic, Department of Surgical Sciences, University of Torino, Turin, Italy
| | - Teresa Rolle
- Eye Clinic, Department of Surgical Sciences, University of Torino, Turin, Italy
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30
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Tatewaki Y, Mutoh T, Thyreau B, Omodaka K, Murata T, Sekiguchi A, Nakazawa T, Taki Y. Phase Difference-Enhanced Magnetic Resonance (MR) Imaging (PADRE) Technique for the Detection of Age-Related Microstructural Changes in Optic Radiation: Comparison with Diffusion Tensor Imaging (DTI). Med Sci Monit 2017; 23:5495-5503. [PMID: 29151112 PMCID: PMC5704509 DOI: 10.12659/msm.905571] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Background The optic radiation (OR) is a white-matter bundle connecting the lateral geniculate body and the visual cortex. Phase difference-enhanced imaging (PADRE) is a new MRI technique that is able to achieve precise delineation of the OR. The aim of this study was to investigate the effect of age on the volume and signal intensity of the OR using PADRE, and to establish a volumetric reference of the OR from a healthy population, compared with diffusion tensor imaging (DTI). Material/Methods Thirty-nine healthy volunteers underwent MR imaging with PADRE and DTI sequences on a 3.0-T scanner. For the volumetric analysis with PADRE, the OR corresponding to the external sagittal stratum was manually traced, while an automated thresholding method was used for the DTI-based volumetric analysis of the OR. Results The mean right and left OR volumes measured from the PADRE images were 1469.0±242.4 mm3 and 1372.6±310.2 mm3, respectively. Although OR volume showed no significant correlation with age, the normalized OR signal intensity showed a linear correlation with increasing age (r2=0.50–0.53; P<0.01). The OR signal intensity on PADRE and DTI-related quantitative parameters for the OR showed significant correlations (r2=0.46–0.49; P<0.01). Conclusions The PADRE technique revealed exceptional preservation of OR volume, even in later life. Moreover, PADRE was able to detect age-related changes in signal intensity of the OR and may contribute to future analyses of pathological neurodegeneration in patients with glaucoma and multiple sclerosis.
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Affiliation(s)
- Yasuko Tatewaki
- Department of Nuclear Medicine and Radiology, Institute of Development, Aging, and Cancer, Tohoku University, Sendai, Miyagi, Japan.,Department of Community Medical Supports, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Tohoku, Japan.,Department of Diagnostic Radiology, Tohoku University Hospital, Sendai, Tohoku, Japan
| | - Tatsushi Mutoh
- Department of Nuclear Medicine and Radiology, Institute of Development, Aging, and Cancer, Tohoku University, Sendai, Miyagi, Japan
| | - Benjamin Thyreau
- Department of Community Medical Supports, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Tohoku, Japan
| | - Kazuko Omodaka
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Tohoku, Japan.,Department of Ophthalmic Imaging and Information Analytics, Tohoku University Graduate School of Medicine, Sendai, Tohoku, Japan
| | - Takaki Murata
- Department of Diagnostic Radiology, Tohoku University Hospital, Sendai, Tohoku, Japan
| | - Atsushi Sekiguchi
- Department of Community Medical Supports, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Tohoku, Japan.,Department of Psychosomatic Research, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Toru Nakazawa
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Tohoku, Japan.,Department of Ophthalmic Imaging and Information Analytics, Tohoku University Graduate School of Medicine, Sendai, Tohoku, Japan
| | - Yasuyuki Taki
- Department of Nuclear Medicine and Radiology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi, Japan.,Department of Community Medical Supports, Tohoku Medical Megabank Organization, Tohoku University, Sendai, Tohoku, Japan
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31
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Lawlor M, Danesh-Meyer H, Levin LA, Davagnanam I, De Vita E, Plant GT. Glaucoma and the brain: Trans-synaptic degeneration, structural change, and implications for neuroprotection. Surv Ophthalmol 2017; 63:296-306. [PMID: 28986311 DOI: 10.1016/j.survophthal.2017.09.010] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 09/11/2017] [Accepted: 09/22/2017] [Indexed: 01/20/2023]
Abstract
A recent hypothesis to enter the literature suggests that glaucoma is a neurodegenerative disease. The basis for this has been the finding of central nervous system changes in glaucoma patients on histology and neuroimaging. It is known that retinal ganglion cell pathology of any cause leads to anterograde and retrograde retinal ganglion cell degeneration, as well as trans-synaptic (transneuronal) anterograde degeneration. Trans-synaptic degeneration has been demonstrated in a range of optic neuropathies including optic nerve transection, optic neuritis, and hereditary optic neuropathies. More recently, similar changes have been confirmed in glaucoma patients using the neuroimaging techniques of voxel-based morphometry and diffusion tensor imaging. Some studies have reported brain changes in glaucoma outside the retino-geniculo-cortical pathway; however, these are preliminary and exploratory in nature. Further research is required to identify whether the degenerative brain changes in glaucoma are entirely secondary to the optic neuropathy or whether there is additional primary central nervous system pathology. This has critical implications for neuroprotective and regenerative treatment strategies and our basic understanding of glaucoma.
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Affiliation(s)
- Mitchell Lawlor
- Save Sight Institute, Discipline of Clinical Ophthalmology and Eye Health, University of Sydney, Sydney, New South Wales, Australia; Department of Neuro-Ophthalmology, Moorfields Eye Hospital, London, United Kingdom.
| | - Helen Danesh-Meyer
- Department of Ophthalmology, University of Auckland, Auckland, New Zealand; University of Melbourne, Parkville, Victoria, Australia
| | - Leonard A Levin
- Departments of Ophthalmology and Neurology & Neurosurgery, McGill University, Montreal, Quebec, Canada; Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, Wisconsin, USA
| | - Indran Davagnanam
- Department of Neuro-Ophthalmology, Moorfields Eye Hospital, London, United Kingdom; Academic Neuroradiological Unit, Department of Brain Repair & Rehabilitation, UCL Institute of Neurology, London, United Kingdom; Lysholm Department of Neuroradiology, National Hospital for Neurology and Neurosurgery, UCL Hospitals Foundation Trust, London, United Kingdom
| | - Enrico De Vita
- Academic Neuroradiological Unit, Department of Brain Repair & Rehabilitation, UCL Institute of Neurology, London, United Kingdom; Lysholm Department of Neuroradiology, National Hospital for Neurology and Neurosurgery, UCL Hospitals Foundation Trust, London, United Kingdom; Department of Biomedical Engineering, King's College London, London, United Kingdom
| | - Gordon T Plant
- Department of Neuro-Ophthalmology, Moorfields Eye Hospital, London, United Kingdom; Department of Neuro-Ophthalmology, National Hospital for Neurology and Neurosurgery, London, United Kingdom; The Medical Eye Unit, St Thomas' Hospital, London, United Kingdom
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32
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Boucard CC, Hanekamp S, Ćurčić-Blake B, Ida M, Yoshida M, Cornelissen FW. Neurodegeneration beyond the primary visual pathways in a population with a high incidence of normal-pressure glaucoma. Ophthalmic Physiol Opt 2017; 36:344-53. [PMID: 27112227 DOI: 10.1111/opo.12297] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 03/07/2016] [Indexed: 11/25/2022]
Abstract
PURPOSE Glaucoma is the most common age-related neurodegenerative eye disease in western society. It is an insidious disease that, when untreated or detected too late, leads inevitably to blindness. An outstanding issue is whether glaucoma should be considered exclusively an eye disease or also a brain disease. To further examine it, we used Diffusion Tensor Imaging (DTI) to study white matter integrity in a Japanese glaucoma population. This population has a very high incidence of normal-pressure glaucoma, in which optic nerve damage occurs in the absence of the elevated eye pressure that characterises the more common form of glaucoma. METHODS We performed DTI in 30 participants with normal-pressure glaucoma and 21 age-matched healthy controls. We used voxel-wise tract-based spatial statistics to compare fractional anisotropy and mean diffusivity of the white matter of the brain between patients and control group. Whole-brain and region of interest-based analyses served to find associations between diffusion indices and clinical measures of glaucomatous damage. RESULTS Fractional Anisotropy was significantly lower in glaucoma patients in a cluster in the right occipital lobe (p < 0.05; family-wise error-corrected) comprising fibres of both the optic radiation and the forceps major. Additional analysis confirmed bilateral involvement of the optic radiations and forceps major and additionally revealed damage to the corpus callosum and parietal lobe (p < 0.09; family-wise error-corrected). The region of interest-based analysis revealed a positive association between Fractional Anisotropy of the optic radiation and optic nerve damage. CONCLUSIONS In this specific population, glaucoma is associated with lower Fractional Anisotropy in the optic radiations, forceps major and corpus callosum. We interpret these reductions as evidence for white matter degeneration in these loci. In particular, the degeneration of the corpus callosum suggests the presence of neurodegeneration of the brain beyond what can be explained on the basis of propagated retinal and pre-geniculate damage. We discuss how this finding links to the emerging view that a brain component that is independent from the eye damage plays a role in the aetiology of glaucoma.
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Affiliation(s)
- Christine C Boucard
- Department of Ophthalmology, Jikei University School of Medicine, Tokyo, Japan
| | - Sandra Hanekamp
- Laboratory for Experimental Ophthalmology, University Medical Center Groningen, University of Groningen, The Netherlands
| | - Branislava Ćurčić-Blake
- Department of Neuroscience, University of Groningen, University Medical Center Groningen, The Netherlands
| | - Masahiro Ida
- Department of Radiology, Tokyo Metropolitan Health and Medical Treatment Corporation, Ebara Hospital, Tokyo, Japan
| | - Masaki Yoshida
- Department of Ophthalmology, Jikei University School of Medicine, Tokyo, Japan
| | - Frans W Cornelissen
- Laboratory for Experimental Ophthalmology, University Medical Center Groningen, University of Groningen, The Netherlands
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33
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Zhong YF, Tang ZH, Qiang JW, Wu LJ, Wang R, Wang J, Jin LX, Xiao ZB. Changes in DTI parameters in the optic tracts of macaque monkeys with monocular blindness. Neurosci Lett 2016; 636:248-253. [PMID: 27864005 DOI: 10.1016/j.neulet.2016.11.030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 10/19/2016] [Accepted: 11/14/2016] [Indexed: 12/27/2022]
Abstract
For humans and non-human primates, the alteration of the visual pathway's white matter fibers after visual deprivation has been partially explored. However, the changes in the optic tracts after the transection of the optic nerve have not been well characterized. In the current study, we attempted to investigate the differences in optic tracts between normal and unilateral optic nerve transected macaque monkeys using diffusion tensor imaging (DTI). Four healthy neonatal macaque monkeys were randomly divided into 2 groups, with 2 in each group. Group A served as a control group, and Group B underwent unilateral (right eye) optic nerve transection to produce monocular blindness. Sixteen months (Group B16M) and thirty-two months (Group B32M) after optic nerve transection, diffusion tensor imaging was performed on all monkeys. Then, we compared fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity (RD) in bilateral optic tracts between Group A and Group B and between Group B16M and Group B32M. In both Group B16M and Group B32M, when compared with normal monkeys in Group A, FA was decreased and MD, AD and RD were increased in the bilateral optic tracts of monkeys with monocular blindness. Furthermore, compared with Group B16M, FA was reduced and MD, AD, RD were more obviously increased in the bilateral optic tracts of Group B32M, and noticeable differences in MD, AD and RD were found between the left and right optic tracts in group B32M. We believe that the results of this study would be helpful in investigation of the histological abnormalities of the integrity damage, axonal degeneration and demyelination of optic tracts in macaque monkeys with monocular blindness by DTI parameters in noninvasively and quantitatively.
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Affiliation(s)
- Yu-Feng Zhong
- Department of Radiology, Jinshan Hospital, Shanghai Medical College, Fudan University, Shanghai, China; Department of Radiology, Eye and ENT Hospital of Shanghai Medical College, Fudan University, Shanghai, China
| | - Zuo-Hua Tang
- Department of Radiology, Eye and ENT Hospital of Shanghai Medical College, Fudan University, Shanghai, China.
| | - Jin-Wei Qiang
- Department of Radiology, Jinshan Hospital, Shanghai Medical College, Fudan University, Shanghai, China.
| | - Ling-Jie Wu
- Department of Otolaryngology, Eye and ENT Hospital of Shanghai Medical College, Fudan University, Shanghai, China
| | - Rong Wang
- Department of Radiology, Eye and ENT Hospital of Shanghai Medical College, Fudan University, Shanghai, China
| | - Jie Wang
- Department of Radiotherapy, Eye and ENT Hospital of Shanghai Medical College, Fudan University, Shanghai, China
| | - Li-Xin Jin
- Siemens Ltd. Healthcare Sector, Shanghai, China
| | - Ze-Bin Xiao
- Department of Radiology, Eye and ENT Hospital of Shanghai Medical College, Fudan University, Shanghai, China
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34
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Murphy MC, Conner IP, Teng CY, Lawrence JD, Safiullah Z, Wang B, Bilonick RA, Kim SG, Wollstein G, Schuman JS, Chan KC. Retinal Structures and Visual Cortex Activity are Impaired Prior to Clinical Vision Loss in Glaucoma. Sci Rep 2016; 6:31464. [PMID: 27510406 PMCID: PMC4980591 DOI: 10.1038/srep31464] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 07/18/2016] [Indexed: 12/14/2022] Open
Abstract
Glaucoma is the second leading cause of blindness worldwide and its pathogenesis remains unclear. In this study, we measured the structure, metabolism and function of the visual system by optical coherence tomography and multi-modal magnetic resonance imaging in healthy subjects and glaucoma patients with different degrees of vision loss. We found that inner retinal layer thinning, optic nerve cupping and reduced visual cortex activity occurred before patients showed visual field impairment. The primary visual cortex also exhibited more severe functional deficits than higher-order visual brain areas in glaucoma. Within the visual cortex, choline metabolism was perturbed along with increasing disease severity in the eye, optic radiation and visual field. In summary, this study showed evidence that glaucoma deterioration is already present in the eye and the brain before substantial vision loss can be detected clinically using current testing methods. In addition, cortical cholinergic abnormalities are involved during trans-neuronal degeneration and can be detected non-invasively in glaucoma. The current results can be of impact for identifying early glaucoma mechanisms, detecting and monitoring pathophysiological events and eye-brain-behavior relationships, and guiding vision preservation strategies in the visual system, which may help reduce the burden of this irreversible but preventable neurodegenerative disease.
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Affiliation(s)
- Matthew C Murphy
- NeuroImaging Laboratory, University of Pittsburgh, Pittsburgh, PA, USA.,UPMC Eye Center, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,Louis J. Fox Center for Vision Restoration, University of Pittsburgh, PA, USA
| | - Ian P Conner
- NeuroImaging Laboratory, University of Pittsburgh, Pittsburgh, PA, USA.,UPMC Eye Center, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,Louis J. Fox Center for Vision Restoration, University of Pittsburgh, PA, USA.,Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, PA, USA
| | - Cindy Y Teng
- NeuroImaging Laboratory, University of Pittsburgh, Pittsburgh, PA, USA.,UPMC Eye Center, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Jesse D Lawrence
- NeuroImaging Laboratory, University of Pittsburgh, Pittsburgh, PA, USA.,UPMC Eye Center, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Zaid Safiullah
- NeuroImaging Laboratory, University of Pittsburgh, Pittsburgh, PA, USA.,UPMC Eye Center, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Bo Wang
- UPMC Eye Center, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,Louis J. Fox Center for Vision Restoration, University of Pittsburgh, PA, USA.,Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, PA, USA
| | - Richard A Bilonick
- UPMC Eye Center, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,Department of Biostatistics, Graduate School of Public Health, University of Pittsburgh, PA, USA
| | - Seong-Gi Kim
- NeuroImaging Laboratory, University of Pittsburgh, Pittsburgh, PA, USA.,Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, PA, USA.,McGowan Institute for Regenerative Medicine, University of Pittsburgh, PA, USA.,Center for Neuroscience Imaging Research, Institute for Basic Science, Suwon, Korea.,Department of Biomedical Engineering, Sungkyunkwan University, Suwon, Korea
| | - Gadi Wollstein
- UPMC Eye Center, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,Louis J. Fox Center for Vision Restoration, University of Pittsburgh, PA, USA.,Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, PA, USA
| | - Joel S Schuman
- UPMC Eye Center, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,Louis J. Fox Center for Vision Restoration, University of Pittsburgh, PA, USA.,Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, PA, USA.,McGowan Institute for Regenerative Medicine, University of Pittsburgh, PA, USA.,Clinical and Translational Science Institute, University of Pittsburgh, Pittsburgh, PA, USA.,Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, Pittsburgh, PA, USA
| | - Kevin C Chan
- NeuroImaging Laboratory, University of Pittsburgh, Pittsburgh, PA, USA.,UPMC Eye Center, Ophthalmology and Visual Science Research Center, Department of Ophthalmology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,Louis J. Fox Center for Vision Restoration, University of Pittsburgh, PA, USA.,Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, PA, USA.,McGowan Institute for Regenerative Medicine, University of Pittsburgh, PA, USA.,Center for the Neural Basis of Cognition, University of Pittsburgh and Carnegie Mellon University, Pittsburgh, PA, USA
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Protective effect of magnesium acetyltaurate against endothelin-induced retinal and optic nerve injury. Neuroscience 2016; 325:153-64. [PMID: 27012609 DOI: 10.1016/j.neuroscience.2016.03.041] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 03/14/2016] [Accepted: 03/15/2016] [Indexed: 12/27/2022]
Abstract
Vascular dysregulation has long been recognized as an important pathophysiological factor underlying the development of glaucomatous neuropathy. Endothelin-1 (ET1) has been shown to be a key player due to its potent vasoconstrictive properties that result in retinal ischemia and oxidative stress leading to retinal ganglion cell (RGC) apoptosis and optic nerve (ON) damage. In this study we investigated the protective effects of magnesium acetyltaurate (MgAT) against retinal cell apoptosis and ON damage. MgAT was administered intravitreally prior to, along with or after administration of ET1. Seven days post-injection, animals were euthanized and retinae were subjected to morphometric analysis, TUNEL and caspase-3 staining. ON sections were stained with toluidine blue and were graded for neurodegenerative effects. Oxidative stress was also estimated in isolated retinae. Pre-treatment with MgAT significantly lowered ET1-induced retinal cell apoptosis as measured by retinal morphometry and TUNEL staining. This group of animals also showed significantly lesser caspase-3 activation and significantly reduced retinal oxidative stress compared to the animals that received intravitreal injection of only ET1. Additionally, the axonal degeneration in ON was markedly reduced in MgAT pretreated animals. The animals that received MgAT co- or post-treatment with ET1 also showed improvement in all parameters; however, the effects were not as significant as observed in MgAT pretreated animals. The current study showed that the intravitreal pre-treatment with MgAT reduces caspase-3 activation and prevents retinal cell apoptosis and axon loss in ON induced by ET1. This protective effect of ET1 was associated with reduced retinal oxidative stress.
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In vivo proton magnetic resonance spectroscopy (1H-MRS) evaluation of the metabolite concentration of optic radiation in primary open angle glaucoma. Eur Radiol 2016; 26:4404-4412. [PMID: 26943134 PMCID: PMC5101279 DOI: 10.1007/s00330-016-4279-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 02/04/2016] [Accepted: 02/08/2016] [Indexed: 10/26/2022]
Abstract
OBJECTIVE To compare the metabolite concentration of optic radiation in glaucoma patients with that of healthy subjects using Proton Magnetic Resonance Spectroscopy (1H-MRS). METHODS 1H-MRS utilising the Single-Voxel Spectroscopy (SVS) technique was performed using a 3.0Tesla MRI on 45 optic radiations (15 from healthy subjects, 15 from mild glaucoma patients, and 15 from severe glaucoma patients). A standardised Volume of Interest (VOI) of 20 × 20 × 20 mm was placed in the region of optic radiation. Mild and severe glaucoma patients were categorised based on the Hodapp-Parrish-Anderson (HPA) classification. Mean and multiple group comparisons for metabolite concentration and metabolite concentration ratio between glaucoma grades and healthy subjects were obtained using one-way ANOVA. RESULTS The metabolite concentration and metabolite concentration ratio between the optic radiations of glaucoma patients and healthy subjects did not demonstrate any significant difference (p > 0.05). CONCLUSION Our findings show no significant alteration of metabolite concentration associated with neurodegeneration that could be measured by single-voxel 1H-MRS in optic radiation among glaucoma patients. KEY POINTS • Glaucoma disease has a neurodegenerative component. • Metabolite changes have been observed in the neurodegenerative process in the brain. • Using SVS, no metabolite changes in optic radiation were attributed to glaucoma.
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Hajiabadi M, Alimohamadi M, Fahlbusch R. Decision Making for Patients With Concomitant Pituitary Macroadenoma and Ophthalmologic Comorbidity: A Clinical Controversy. World Neurosurg 2015; 84:147-53. [PMID: 25769486 DOI: 10.1016/j.wneu.2015.02.043] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 02/21/2015] [Accepted: 02/24/2015] [Indexed: 11/28/2022]
Abstract
BACKGROUND Coexisting complex visual field defects and serious ophthalmologic comorbidities make the management of the pituitary macroadenomas more challenging. Diffusion tensor imaging (DTI) magnetic resonance imaging that tracks neural fibers in the white matter has been used recently to visualize the impact of different pathologies on cranial nerves. This study explains application of anterior optic pathway tractography for patients with ophthalmologic comorbidities and pituitary adenoma. METHODS Two patients with atypical visual field defects caused by nonfunctional pituitary macroadenoma and simultaneous ophthalmologic morbidities (one glaucoma and the other giant cell arteritis) were selected for surgical decompression of the anterior optic apparatus. Standard perimetry and optic pathway DTI were done preoperatively, intraoperatively, and 3 months after surgery. RESULTS The nontypical pattern of visual field defect could not differentiate between the ophthalmologic disease and the chiasmatic compression attributable to pituitary macroadenoma as the main cause. Preoperative visual pathway DTI tractography showed lack of decussating chiasmatic fibers in both of the patients. DTI tractography revealed the reappearance of these fibers intraoperatively in one and postoperatively in the other one. Three months after surgery, the visual field and acuity improved and DTI tractography confirmed presence of crossing chiasmatic fibers. CONCLUSION Visual pathway DTI tractography is a promising adjunct to the standard perimetry in preoperative assessment of pituitary macroadenoma with serious ophthalmologic comorbidities. It also may be useful in the intraoperative determination of the optic pathway decompression and for following the visual outcome of these patients after surgery.
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Affiliation(s)
- Mohamadreza Hajiabadi
- International Neuroscience Institute, Hannover, Germany; Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran; Iranian International Neuroscience Institute, Tehran University of Medical Sciences (TUMS), Tehran, Iran.
| | - Maysam Alimohamadi
- International Neuroscience Institute, Hannover, Germany; Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran; Iranian International Neuroscience Institute, Tehran University of Medical Sciences (TUMS), Tehran, Iran
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Brain imaging in glaucoma from clinical studies to clinical practice. PROGRESS IN BRAIN RESEARCH 2015; 221:159-75. [DOI: 10.1016/bs.pbr.2015.06.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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