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Wang L, Ji Y, Ding H, Tian Q, Fan K, Shi D, Yu C, Qin W. Abnormal cerebral blood flow in patients with Leber's hereditary optic neuropathy. Brain Imaging Behav 2023; 17:471-480. [PMID: 37368154 DOI: 10.1007/s11682-023-00775-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/04/2023] [Indexed: 06/28/2023]
Abstract
PURPOSE The study aimed to unravel abnormal cerebral blood flow (CBF) in patients with Leber's hereditary optic neuropathy (LHON) using arterial spin labeling (ASL) and to investigate the associations among disrupted CBF, disease duration, and neuro-ophthalmological impairment. METHODS ASL perfusion imaging data was collected from 20 patients with acute LHON, 29 patients with chronic LHON, and 37 healthy controls. We used a one-way analysis of covariance to test the intergroup differences in CBF. Linear and nonlinear curve fit models were applied to explore the associations among CBF, disease duration, and neuro-ophthalmological metrics. RESULTS Brain regions differed in LHON patients, including the left sensorimotor and bilateral visual areas (p < 0.05, cluster-wise family-wise error correction). Acute and chronic LHON patients demonstrated lower CBF in bilateral calcarine than the healthy controls. Chronic LHON had lower CBF in the left middle frontal gyrus and sensorimotor cortex, and temporal-partial junction than the healthy controls and acute LHON. A significant logarithmic negative correlation was shown between CBF of left middle frontal gyrus and disease duration. A significant linear positive correlation was found between retinal nerve fiber layer thickness and CBF in left middle frontal gyrus, and negative correlations between loss of variance and CBF in left middle frontal gyrus and sensorimotor cortex (p < 0.05, Bonferroni correction). CONCLUSION LHON patients exhibited reduced CBF in the visual pathway, sensorimotor and higher-tier cognitive areas. Disease duration and neuro-ophthalmological impairments can influence the metabolism of non-visual areas.
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Affiliation(s)
- Ling Wang
- Department of Medical Imaging, Henan Provincial People's Hospital, Zhengzhou, 450003, China
| | - Yi Ji
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Hao Ding
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, 300052, China
- School of Medical Imaging, Tianjin Medical University, Tianjin, 300070, China
| | - Qin Tian
- Department of Medical Imaging, Henan Provincial People's Hospital, Zhengzhou, 450003, China
| | - Ke Fan
- Henan Eye Institute, Henan Eye Hospital, Zhengzhou University People's Hospital, Henan Provincial People's Hospital, Zhengzhou, 450003, China
| | - Dapeng Shi
- Department of Medical Imaging, Henan Provincial People's Hospital, Zhengzhou, 450003, China.
- Department of Medical Imaging, Henan Provincial People's Hospital, Sanquan College of Xinxiang Medical University, Weiwu Road No. 7, Jinshui District, ZhengZhou, Henan Province, China.
| | - Chunshui Yu
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, 300052, China.
- Department of Radiology, Tianjin Medical University General Hospital, Anshan Road No. 154, Heping District, Tianjin, 300052, China.
| | - Wen Qin
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, 300052, China.
- Department of Radiology, Tianjin Medical University General Hospital, Anshan Road No. 154, Heping District, Tianjin, 300052, China.
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Tribble JR, Hui F, Quintero H, El Hajji S, Bell K, Di Polo A, Williams PA. Neuroprotection in glaucoma: Mechanisms beyond intraocular pressure lowering. Mol Aspects Med 2023; 92:101193. [PMID: 37331129 DOI: 10.1016/j.mam.2023.101193] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 05/25/2023] [Accepted: 06/04/2023] [Indexed: 06/20/2023]
Abstract
Glaucoma is a common, complex, multifactorial neurodegenerative disease characterized by progressive dysfunction and then loss of retinal ganglion cells, the output neurons of the retina. Glaucoma is the most common cause of irreversible blindness and affects ∼80 million people worldwide with many more undiagnosed. The major risk factors for glaucoma are genetics, age, and elevated intraocular pressure. Current strategies only target intraocular pressure management and do not directly target the neurodegenerative processes occurring at the level of the retinal ganglion cell. Despite strategies to manage intraocular pressure, as many as 40% of glaucoma patients progress to blindness in at least one eye during their lifetime. As such, neuroprotective strategies that target the retinal ganglion cell and these neurodegenerative processes directly are of great therapeutic need. This review will cover the recent advances from basic biology to on-going clinical trials for neuroprotection in glaucoma covering degenerative mechanisms, metabolism, insulin signaling, mTOR, axon transport, apoptosis, autophagy, and neuroinflammation. With an increased understanding of both the basic and clinical mechanisms of the disease, we are closer than ever to a neuroprotective strategy for glaucoma.
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Affiliation(s)
- James R Tribble
- Department of Clinical Neuroscience, Division of Eye and Vision, St. Erik Eye Hospital, Karolinska Institutet, Stockholm, Sweden
| | - Flora Hui
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia; Department of Optometry & Vision Sciences, The University of Melbourne, Melbourne, Australia
| | - Heberto Quintero
- Department of Neuroscience, University of Montreal, Montreal, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Canada
| | - Sana El Hajji
- Department of Neuroscience, University of Montreal, Montreal, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Canada
| | - Katharina Bell
- NHMRC Clinical Trials Centre, University of Sydney, Australia; Eye ACP Duke-NUS, Singapore
| | - Adriana Di Polo
- Department of Neuroscience, University of Montreal, Montreal, Canada; Neuroscience Division, Centre de recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, Canada
| | - Pete A Williams
- Department of Clinical Neuroscience, Division of Eye and Vision, St. Erik Eye Hospital, Karolinska Institutet, Stockholm, Sweden.
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Ji Y, Wang L, Ding H, Tian Q, Fan K, Shi D, Yu C, Qin W. Aberrant neurovascular coupling in Leber's hereditary optic neuropathy: Evidence from a multi-model MRI analysis. Front Neurosci 2023; 16:1050772. [PMID: 36703998 PMCID: PMC9871937 DOI: 10.3389/fnins.2022.1050772] [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: 09/22/2022] [Accepted: 12/22/2022] [Indexed: 01/12/2023] Open
Abstract
The study aimed to investigate the neurovascular coupling abnormalities in Leber's hereditary optic neuropathy (LHON) and their associations with clinical manifestations. Twenty qualified acute Leber's hereditary optic neuropathy (A-LHON, disease duration ≤ 1 year), 29 chronic Leber's hereditary optic neuropathy (C-LHON, disease duration > 1 year), as well as 37 healthy controls (HCs) were recruited. The neurovascular coupling strength was quantified as the ratio between regional homogeneity (ReHo), which represents intrinsic neuronal activity and relative cerebral blood flow (CBF), representing microcirculatory blood supply. A one-way analysis of variance was used to compare intergroup differences in ReHo/CBF ratio with gender and age as co-variables. Pearson's Correlation was used to clarify the association between ReHo, CBF, and neurovascular coupling strength. Furthermore, we applied linear and exponential non-linear regression models to explore the associations among ReHo/CBF, disease duration, and neuro-ophthalmological metrics. Compared with HCs, A_LHON, and C_LHON patients demonstrated a higher ReHo/CBF ratio than the HCs in the bilateral primary visual cortex (B_CAL), which was accompanied by reduced CBF while preserved ReHo. Besides, only C_LHON had a higher ReHo/CBF ratio and reduced CBF in the left middle temporal gyrus (L_MTG) and left sensorimotor cortex (L_SMC) than the HCs, which was accompanied by increased ReHo in L_MTG (p < 1.85e-3, Bonferroni correction). A-LHON and C-LHON showed a negative Pearson correlation between ReHo/CBF ratio and CBF in B_CAL, L_SMC, and L_MTG. Only C_LHON showed a weak positive correlation between ReHo/CBF ratio and ReHo in L_SMC and L_MTG (p < 0.05, uncorrected). Finally, disease duration was positively correlated with ReHo/CBF ratio of L_SMC (Exponential: Radj2 = 0.23, p = 8.66e-4, Bonferroni correction). No statistical correlation was found between ReHo/CBF ratio and neuro-ophthalmological metrics (p > 0.05, Bonferroni correction). Brain neurovascular "dyscoupling" within and outside the visual system might be an important neurological mechanism of LHON.
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Affiliation(s)
- Yi Ji
- Tianjin Key Lab of Functional Imaging, Department of Radiology, Tianjin Medical University General Hospital, Tianjin, China
| | - Ling Wang
- Department of Medical Imaging, Henan Provincial People’s Hospital, Zhengzhou, China
| | - Hao Ding
- Tianjin Key Lab of Functional Imaging, Department of Radiology, Tianjin Medical University General Hospital, Tianjin, China,School of Medical Imaging, Tianjin Medical University, Tianjin, China
| | - Qin Tian
- Department of Medical Imaging, Henan Provincial People’s Hospital, Zhengzhou, China
| | - Ke Fan
- Henan Eye Institute, Henan Eye Hospital, Henan Provincial People’s Hospital, Zhengzhou University People’s Hospital, Zhengzhou, China
| | - Dapeng Shi
- Department of Medical Imaging, Henan Provincial People’s Hospital, Zhengzhou, China,*Correspondence: Dapeng Shi,
| | - Chunshui Yu
- Tianjin Key Lab of Functional Imaging, Department of Radiology, Tianjin Medical University General Hospital, Tianjin, China,Chunshui Yu,
| | - Wen Qin
- Tianjin Key Lab of Functional Imaging, Department of Radiology, Tianjin Medical University General Hospital, Tianjin, China,Wen Qin,
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Manners DN, Gramegna LL, La Morgia C, Sighinolfi G, Fiscone C, Carbonelli M, Romagnoli M, Carelli V, Tonon C, Lodi R. Multishell Diffusion MR Tractography Yields Morphological and Microstructural Information of the Anterior Optic Pathway: A Proof-of-Concept Study in Patients with Leber’s Hereditary Optic Neuropathy. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19116914. [PMID: 35682499 PMCID: PMC9180110 DOI: 10.3390/ijerph19116914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/23/2022] [Accepted: 05/27/2022] [Indexed: 12/04/2022]
Abstract
Tractography based on multishell diffusion-weighted magnetic resonance imaging (DWI) can be used to estimate the course of myelinated white matter tracts and nerves, yielding valuable information regarding normal anatomy and variability. DWI is sensitive to the local tissue microstructure, so tractography can be used to estimate tissue properties within nerve tracts at a resolution of millimeters. This study aimed to test the applicability of the method using a disease with a well-established pattern of myelinated nerve involvement. Eight patients with LHON and 13 age-matched healthy controls underwent tractography of the anterior optic pathway. Diffusion parameters were compared between groups, and for the patient group correlated with clinical/ophthalmological parameters. Tractography established the course of the anterior optic pathway in both patients and controls. Localized changes in fractional anisotropy were observed, and related to estimates of different tissue compartments within the nerve and tract. The proportion of different compartments correlated with markers of disease severity. The method described allows both anatomical localization and tissue characterization in vivo, permitting both visualization of variation at the individual level and statistical inference at the group level. It provides a valuable adjunct to ex vivo anatomical and histological study of normal variation and disease processes.
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Affiliation(s)
- David Neil Manners
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, 40138 Bologna, Italy; (L.L.G.); (G.S.); (C.F.); (M.C.); (V.C.); (C.T.); (R.L.)
- Correspondence:
| | - Laura Ludovica Gramegna
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, 40138 Bologna, Italy; (L.L.G.); (G.S.); (C.F.); (M.C.); (V.C.); (C.T.); (R.L.)
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bellaria Hospital, 40139 Bologna, Italy; (C.L.M.); (M.R.)
| | - Chiara La Morgia
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bellaria Hospital, 40139 Bologna, Italy; (C.L.M.); (M.R.)
| | - Giovanni Sighinolfi
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, 40138 Bologna, Italy; (L.L.G.); (G.S.); (C.F.); (M.C.); (V.C.); (C.T.); (R.L.)
| | - Cristiana Fiscone
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, 40138 Bologna, Italy; (L.L.G.); (G.S.); (C.F.); (M.C.); (V.C.); (C.T.); (R.L.)
| | - Michele Carbonelli
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, 40138 Bologna, Italy; (L.L.G.); (G.S.); (C.F.); (M.C.); (V.C.); (C.T.); (R.L.)
| | - Martina Romagnoli
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bellaria Hospital, 40139 Bologna, Italy; (C.L.M.); (M.R.)
| | - Valerio Carelli
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, 40138 Bologna, Italy; (L.L.G.); (G.S.); (C.F.); (M.C.); (V.C.); (C.T.); (R.L.)
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bellaria Hospital, 40139 Bologna, Italy; (C.L.M.); (M.R.)
| | - Caterina Tonon
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, 40138 Bologna, Italy; (L.L.G.); (G.S.); (C.F.); (M.C.); (V.C.); (C.T.); (R.L.)
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bellaria Hospital, 40139 Bologna, Italy; (C.L.M.); (M.R.)
| | - Raffaele Lodi
- Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, 40138 Bologna, Italy; (L.L.G.); (G.S.); (C.F.); (M.C.); (V.C.); (C.T.); (R.L.)
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bellaria Hospital, 40139 Bologna, Italy; (C.L.M.); (M.R.)
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Tian Q, Wang L, Zhang Y, Fan K, Liang M, Shi D, Qin W, Ding H. Brain Gray Matter Atrophy and Functional Connectivity Remodeling in Patients With Chronic LHON. Front Neurosci 2022; 16:885770. [PMID: 35645726 PMCID: PMC9135140 DOI: 10.3389/fnins.2022.885770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/19/2022] [Indexed: 11/23/2022] Open
Abstract
Purpose The aim of this study was to investigate the brain gray matter volume (GMV) and spontaneous functional connectivity (FC) changes in patients with chronic Leber's hereditary optic neuropathy (LHON), and their relations with clinical measures. Methods A total of 32 patients with chronic LHON and matched sighted healthy controls (HC) underwent neuro-ophthalmologic examinations and multimodel magnetic resonance imaging (MRI) scans. Voxel-based morphometry (VBM) was used to detect the GMV differences between the LHON and HC. Furthermore, resting-state FC analysis using the VBM-identified clusters as seeds was carried out to detect potential functional reorganization in the LHON. Finally, the associations between the neuroimaging and clinical measures were performed. Results The average peripapillary retinal nerve fiber layer (RNFL) thickness of the chronic LHON was significantly thinner (T = −16.421, p < 0.001), and the mean defect of the visual field was significantly higher (T = 11.28, p < 0.001) than the HC. VBM analysis demonstrated a significantly lower GMV of bilateral calcarine gyri (CGs) in the LHON than in the HC (p < 0.05). Moreover, in comparison with the HC, the LHON had significantly lower FC between the centroid of the identified left CG and ipsilateral superior occipital gyrus (SOG) and higher FC between this cluster and the ipsilateral posterior cingulate gyrus (p < 0.05, corrected). Finally, the GMV of the left CG was negatively correlated with the LHON duration (r = −0.535, p = 0.002), and the FC between the left CG and the ipsilateral posterior cingulate gyrus of the LHON was negatively correlated with the average peripapillary RNFL thickness (r = −0.522, p = 0.003). Conclusion The atrophied primary visual cortex of the chronic LHON may be caused by transneuronal degeneration following the retinal damage. Moreover, our findings suggest that the functional organization of the atrophied primary visual cortex has been reshaped in the chronic LHON.
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Affiliation(s)
- Qin Tian
- Department of Medical Imaging, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, China
| | - Ling Wang
- Department of Medical Imaging, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, China
| | - Yu Zhang
- Department of Radiology, Tianjin Medical University, Tianjin, China
- Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, China
| | - Ke Fan
- Henan Eye Institute, Henan Eye Hospital, Henan Provincial People's Hospital, Zhengzhou University People's Hospital, Zhengzhou, China
| | - Meng Liang
- Department of Radiology, Tianjin Medical University, Tianjin, China
- Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, China
- School of Medical Imaging, Tianjin Medical University, Tianjin, China
| | - Dapeng Shi
- Department of Medical Imaging, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, China
- *Correspondence: Dapeng Shi
| | - Wen Qin
- Department of Radiology, Tianjin Medical University, Tianjin, China
- Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, China
- Wen Qin
| | - Hao Ding
- Department of Radiology, Tianjin Medical University, Tianjin, China
- Tianjin Key Laboratory of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, China
- School of Medical Imaging, Tianjin Medical University, Tianjin, China
- Hao Ding
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Zhao J, Zhang Q, Wang J. Magnetic Resonance Imaging Findings in the Pregeniculate Visual Pathway in Leber Hereditary Optic Neuropathy. J Neuroophthalmol 2022; 42:e153-e158. [PMID: 34417770 PMCID: PMC8834162 DOI: 10.1097/wno.0000000000001383] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Current research has not provided a consistent and qualitative description of MRI features in Leber hereditary optic neuropathy (LHON). Our study aims to investigate the MRI findings in the pregeniculate visual pathway and discuss their clinical significance in LHON. METHODS Orbital MRI was retrospectively analyzed for 53 patients with LHON (101 afflicted eyes) admitted to the Department of Neurology, Beijing Tongren Hospital, Capital Medical University, from 2014 to 2019. We described the imaging abnormalities and discussed their associations with the time interval from the onset of vision loss to the performance of MRI (TIOVP), prevalence of m.11778G>A, and best-corrected visual acuity (BCVA). RESULTS T2 hyperintense signal (HS) was determined in 82 afflicted eyes, with 34 located in the intraorbital segment (IO) of the optic nerve (ON), 26 in the IO concurrent with intracanalicular segment (ICn), 14 in the IO and ICn concurrent with intracranial segment (ICr) of the ON, 4 in the IO, ICn, and ICr concurrent with optic chiasm (OCh), and 4 in the IO, ICn, ICr, and OCh concurrent with optic tract (OTr). MRI was normal in the remaining 19 afflicted eyes. Among the 6 groups, no statistical differences were found in the TIOVP (P = 0.071), prevalence of m.11778G>A (P = 0.234), and BCVA (P = 0.076). As T2 HS extended, the BCVA gradually decreased. Nineteen of the 54 afflicted eyes revealed contrast enhancement, with the TIOVP ranging from 0.25 to 6 months. CONCLUSIONS T2 HS was common in the pregeniculate visual pathway in LHON. It was not correlated with the prevalence of m.11778G>A and did not benefit in disease staging. As it extended, the BCVA gradually decreased. Contrast enhancement was relatively rare, always occurring in the subacute stage.
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Chow-Wing-Bom HT, Callaghan MF, Wang J, Wei S, Dick F, Yu-Wai-Man P, Dekker TM. Neuroimaging in Leber Hereditary Optic Neuropathy: State-of-the-art and future prospects. Neuroimage Clin 2022; 36:103240. [PMID: 36510411 PMCID: PMC9668671 DOI: 10.1016/j.nicl.2022.103240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Revised: 06/14/2022] [Accepted: 10/17/2022] [Indexed: 11/05/2022]
Abstract
Leber Hereditary Optic Neuropathy (LHON) is an inherited mitochondrial retinal disease that causes the degeneration of retinal ganglion cells and leads to drastic loss of visual function. In the last decades, there has been a growing interest in using Magnetic Resonance Imaging (MRI) to better understand mechanisms of LHON beyond the retina. This is partially due to the emergence of gene-therapies for retinal diseases, and the accompanying expanded need for reliably quantifying and monitoring visual processing and treatment efficiency in patient populations. This paper aims to draw a current picture of key findings in this field so far, the challenges of using neuroimaging methods in patients with LHON, and important open questions that MRI can help address about LHON disease mechanisms and prognoses, including how downstream visual brain regions are affected by the disease and treatment and why, and how scope for neural plasticity in these pathways may limit or facilitate recovery.
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Affiliation(s)
- Hugo T Chow-Wing-Bom
- Institute of Ophthalmology, University College London (UCL), London, United Kingdom; Birkbeck/UCL Centre for NeuroImaging, London, United Kingdom.
| | - Martina F Callaghan
- Wellcome Centre for Human Neuroimaging, UCL Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Junqing Wang
- Department of Ophthalmology, The Chinese People's Liberation Army General Hospital, The Chinese People's Liberation Army Medical School, Beijing, China
| | - Shihui Wei
- Department of Ophthalmology, The Chinese People's Liberation Army General Hospital, The Chinese People's Liberation Army Medical School, Beijing, China
| | - Frederic Dick
- Birkbeck/UCL Centre for NeuroImaging, London, United Kingdom; Department of Psychological Sciences, Birkbeck, University of London, United Kingdom; Department of Experimental Psychology, UCL, London, United Kingdom
| | - Patrick Yu-Wai-Man
- Institute of Ophthalmology, University College London (UCL), London, United Kingdom; John van Geest Centre for Brain Repair and MRC Mitochondrial Biology Unit, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom; Cambridge Eye Unit, Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, United Kingdom; Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
| | - Tessa M Dekker
- Institute of Ophthalmology, University College London (UCL), London, United Kingdom; Birkbeck/UCL Centre for NeuroImaging, London, United Kingdom; Department of Experimental Psychology, UCL, London, United Kingdom
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Evangelisti S, La Morgia C, Testa C, Manners DN, Brizi L, Bianchini C, Carbonelli M, Barboni P, Sadun AA, Tonon C, Carelli V, Vandewalle G, Lodi R. Brain functional MRI responses to blue light stimulation in Leber’s hereditary optic neuropathy. Biochem Pharmacol 2021; 191:114488. [DOI: 10.1016/j.bcp.2021.114488] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 02/18/2021] [Accepted: 02/19/2021] [Indexed: 12/20/2022]
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Ptito M, Paré S, Dricot L, Cavaliere C, Tomaiuolo F, Kupers R. A quantitative analysis of the retinofugal projections in congenital and late-onset blindness. NEUROIMAGE-CLINICAL 2021; 32:102809. [PMID: 34509923 PMCID: PMC8435915 DOI: 10.1016/j.nicl.2021.102809] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 07/14/2021] [Accepted: 08/24/2021] [Indexed: 01/22/2023]
Abstract
Congenital (CB) and late blind (LB) affects the integrity brain visual structures. We measured the integrity of the retino-fugal system using structural MRI images. Optic nerve, optic tract, optic chiasm and LGN were reduced by 50 to 60% in CB and LB. There were no differences between CB and LB. In LB, optic nerve volume correlated negatively with blindness duration.
Vision loss early in life has dramatic consequences on the organization of the visual system and hence on structural plasticity of its remnant components. Most of the studies on the anatomical changes in the brain following visual deprivation have focused on the re-organization of the visual cortex and its afferent and efferent projections. In this study, we performed a quantitative analysis of the volume and size of the optic chiasm, optic nerve, optic tract and the lateral geniculate nucleus (LGN), the retino recipient thalamic nucleus. Analysis was carried out on structural T1-weighted MRIs from 22 congenitally blind (CB), 14 late blind (LB) and 29 age -and sex-matched sighted control (SC) subjects. We manually segmented the optic nerve, optic chiasm and optic tract, while LGN volumes were extracted using in-house software. We also measured voxel intensity of optic nerve, optic chiasm and optic tract. Mean volumes of the optic nerve, optic tract and optic chiasm were reduced by 50 to 60% in both CB and LB participants. No significant differences were found between the congenitally and late-onset blind participants for any of the measures. Our data further revealed reduced white matter voxel intensities in optic nerve, optic chiasm and optic tract in blind compared to sighted participants, suggesting decreased myelin content in the atrophied white matter. The LGN was reduced by 50% and 44% in CB and LB, respectively. In LB, optic nerve volume correlated negatively with the blindness duration index; no such correlation was found for optic chiasm, optic tract and LGN. The observation that despite the absence of visual input about half of the subcortical retinofugal projections are structurally preserved raises the question of their functional role. One possibility is that the surviving fibers play a role in the maintenance of circadian rhythms in the blind through the intrinsically photosensitive melanopsin-containing retinal ganglion cells.
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Affiliation(s)
- Maurice Ptito
- School of Optometry, University of Montreal, Montreal, QC, Canada; BRAINlab, University of Copenhagen, Copenhagen, Denmark; Danish Research Center for Magnetic Resonance (DRCMR), Copenhagen University Hospital, Hvidovre, Denmark
| | - Samuel Paré
- School of Optometry, University of Montreal, Montreal, QC, Canada
| | - Laurence Dricot
- Institute of NeuroScience (IoNS), Université catholique de Louvain (UCLouvain), Belgium
| | - Carlo Cavaliere
- IRCCS SDN, Naples, Italy; Coma Science Group, Cyclotron Research Center and Neurology Department, University and University Hospital of Liège, Liège, Belgium
| | - Francesco Tomaiuolo
- Univesità degli Studi di Messina, Dipartimento di Medicina Clinica e Sperimentale
| | - Ron Kupers
- School of Optometry, University of Montreal, Montreal, QC, Canada; BRAINlab, University of Copenhagen, Copenhagen, Denmark; Institute of NeuroScience (IoNS), Université catholique de Louvain (UCLouvain), Belgium.
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Wang L, Ding H, Chen BT, Fan K, Tian Q, Long M, Liang M, Shi D, Yu C, Qin W. Occult primary white matter impairment in Leber hereditary optic neuropathy. Eur J Neurol 2021; 28:2871-2881. [PMID: 34166558 DOI: 10.1111/ene.14995] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 05/17/2021] [Accepted: 06/22/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND PURPOSE Leber hereditary optic neuropathy (LHON) is a disease maternally inherited from mitochondria that predominantly impairs the retinal ganglion cells and their axons. To identify whether occult brain white matter (WM) impairment is involved, a voxel-based analysis (VBA) of diffusion metrics was carried out in LHON patients with normal-appearing brain parenchyma. METHODS Fifty-four symptomatic LHON patients (including 22 acute LHON with vision loss for ≤12 months, and 32 chronic LHON) without any visible brain lesions and 36 healthy controls (HCs) were enrolled in this study. VBA was applied to quantify the WM microstructural changes of LHON patients. Finally, the associations of the severity of WM impairment with disease duration and ophthalmologic deficits were assessed. RESULTS Compared with the HCs, the average retinal nerve fiber layer (RNFL) thickness was significantly reduced in patients with chronic LHON, whereas it was increased in patients with acute LHON (p < 0.05, corrected). VBA identified significantly decreased fractional anisotropy widely in WM in both the acute and chronic LHON patients, including the left anterior thalamic radiation and superior longitudinal fasciculus, and bilateral corticospinal tract, dentate nuclei, inferior longitudinal fasciculus, forceps major, and optic radiation (OR; p < 0.05, corrected). The integrity of most WM structures (except for the OR) was correlated with neither disease duration nor RNFL thickness (p > 0.05, corrected). CONCLUSIONS Occult primary impairment of widespread brain WM is present in LHON patients. The coexisting primary and secondary WM impairment may jointly contribute to the pathological process of LHON.
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Affiliation(s)
- Ling Wang
- Department of Medical Imaging, Henan Provincial People's Hospital, Zhengzhou, China
| | - Hao Ding
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, China.,School of Medical Imaging, Tianjin Medical University, Tianjin, China
| | - Bihong T Chen
- Department of Diagnostic Radiology, City of Hope National Medical Center, Duarte, California, USA
| | - Ke Fan
- Henan Eye Institute, Henan Eye Hospital, Henan Provincial People's Hospital, Zhengzhou, China
| | - Qin Tian
- Department of Medical Imaging, Henan Provincial People's Hospital, Zhengzhou, China
| | - Miaomiao Long
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, China
| | - Meng Liang
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, China.,School of Medical Imaging, Tianjin Medical University, Tianjin, China
| | - Dapeng Shi
- Department of Medical Imaging, Henan Provincial People's Hospital, Zhengzhou, China
| | - Chunshui Yu
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, China
| | - Wen Qin
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin, China
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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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Zhang J, Wang L, Ding H, Fan K, Tian Q, Liang M, Sun Z, Shi D, Qin W. Abnormal large-scale structural rich club organization in Leber's hereditary optic neuropathy. NEUROIMAGE-CLINICAL 2021; 30:102619. [PMID: 33752075 PMCID: PMC8010853 DOI: 10.1016/j.nicl.2021.102619] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 02/23/2021] [Accepted: 03/02/2021] [Indexed: 12/24/2022]
Abstract
LHON patients suffered large-scale structural network disruption. Non-rich club connections may be more vulnerable in the LHON. Both primary and secondary connectivity damage may coexist in the LHON.
Objective The purpose of this study was to investigate whether the large-scale structural rich club organization was abnormal in patients with Leber's hereditary optic neuropathy (LHON) using diffusion tensor imaging (DTI), and the associations among disrupted brain structural connectivity, disease duration, and neuro-ophthalmological impairment. Methods Nineteen acute, 34 chronic LHON patients, and 36 healthy controls (HC) underwent DTI and neuro-ophthalmological measurements. The brain structural network and rich club organization were constructed based on deterministic fiber tracking at the individual level. Then intergroup differences among the acute, chronic LHON patients and healthy controls (HC) in three types of structural connections, including rich club, feeder, and local ones, were compared. Network-based Statistics (NBS) was also used to test the intergroup connectivity differences for each fiber. Several linear and nonlinear curve fit models were applied to explore the associations among large-scale brain structural connectivity, disease duration, and neuro-ophthalmological metrics. Results Compared to the HC, both the acute and chronic LHON patients had consistently significantly lower fractional anisotropy (FA) and higher radial diffusion (RD) for feeder connections (p < 0.05, FDR correction). Acute LHON patients had significantly lower FA and higher RD for local connections (p < 0.05, FDR correction). There was no significant difference in large-scale brain structural connectivity between acute and chronic LHON (p > 0.05, FDR correction). NBS also identified reduced FA of three feeder connections and five local ones linking visual, auditory, and basal ganglia areas in LHON patients (p < 0.05, FDR correction). No structural connections showed linear or nonlinear association with either disease duration or neuro-ophthalmological indicators (p > 0.05, FDR correction). A significant negative correlation was shown between the retinal nerve fiber layer (RNFL) thickness and disease duration (p < 0.05, FDR correction). Conclusions Abnormal rich club organization of the structural network was identified in both the acute and chronic LHON. Furthermore, our findings suggest the coexistence of both primary and secondary connectivity damage in the LHON.
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Affiliation(s)
- Jiahui Zhang
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin 300052, China
| | - Ling Wang
- Department of Medical Imaging, Henan Provincial People's Hospital, Zhengzhou 450003, China
| | - Hao Ding
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin 300052, China; School of Medical Imaging, Tianjin Medical University, Tianjin 300070, China
| | - Ke Fan
- Henan Eye Institute, Henan Eye Hospital, Zhengzhou University People's Hospital, Henan Provincial People's Hospital, Zhengzhou 450003, China
| | - Qin Tian
- Department of Medical Imaging, Henan Provincial People's Hospital, Zhengzhou 450003, China
| | - Meng Liang
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin 300052, China; School of Medical Imaging, Tianjin Medical University, Tianjin 300070, China
| | - Zhihua Sun
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin 300052, China.
| | - Dapeng Shi
- Department of Medical Imaging, Henan Provincial People's Hospital, Zhengzhou 450003, China.
| | - Wen Qin
- Department of Radiology & Tianjin Key Lab of Functional Imaging, Tianjin Medical University General Hospital, Tianjin 300052, China.
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13
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Decreased Volume of Lateral and Medial Geniculate Nuclei in Patients with LHON Disease-7 Tesla MRI Study. J Clin Med 2020; 9:jcm9092914. [PMID: 32927622 PMCID: PMC7565643 DOI: 10.3390/jcm9092914] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 09/04/2020] [Accepted: 09/06/2020] [Indexed: 11/17/2022] Open
Abstract
Leber’s hereditary optic neuropathy (LHON) is a maternally inherited genetic disorder leading to severe and bilateral loss of central vision, with a young male predilection. In recent years, multiple studies examined structural abnormalities in visual white matter tracts such as the optic tract and optic radiation. However, it is still unclear if the disease alters only some parts of the white matter architecture or whether the changes also affect grey matter parts of the visual pathway. This study aimed at improving our understanding of morphometric changes in the lateral (LGN) and medial (MGN) geniculate nuclei and their associations with the clinical picture in LHON by the application of a submillimeter surface-based analysis approach to the ultra-high-field 7T magnetic resonance imaging data. To meet these goals, fifteen LHON patients and fifteen age-matched healthy subjects were examined. A quantitative analysis of the LGN and MGN volume was performed for all individuals. Additionally, morphometric results of LGN and MGN were correlated with variables covering selected aspects of the clinical picture of LHON. In comparison with healthy controls (HC), LHON participants showed a significantly decreased volume of the right LGN and the right MGN. Nevertheless, the volume of the right LGN was strongly correlated with the averaged thickness value of the right retinal nerve fiber layer (RNFL). The abnormalities in the volume of the LHON patients’ thalamic nuclei indicate that the disease can cause changes not only in the white matter areas constituting visual tracts but also in the grey matter structures. Furthermore, the correlation between the changes in the LGN volume and the RNFL, as well as the right optic nerve surface area located proximally to the eyeball, suggest some associations between the atrophy of these structures. However, to fully confirm this observation, longitudinal studies should be conducted.
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14
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Guo L, Davis BM, Ravindran N, Galvao J, Kapoor N, Haamedi N, Shamsher E, Luong V, Fico E, Cordeiro MF. Topical recombinant human Nerve growth factor (rh-NGF) is neuroprotective to retinal ganglion cells by targeting secondary degeneration. Sci Rep 2020; 10:3375. [PMID: 32099056 PMCID: PMC7042238 DOI: 10.1038/s41598-020-60427-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 01/16/2020] [Indexed: 12/13/2022] Open
Abstract
Optic neuropathy is a major cause of irreversible blindness worldwide, and no effective treatment is currently available. Secondary degeneration is believed to be the major contributor to retinal ganglion cell (RGC) death, the endpoint of optic neuropathy. Partial optic nerve transection (pONT) is an established model of optic neuropathy. Although the mechanisms of primary and secondary degeneration have been delineated in this model, until now how this is influenced by therapy is not well-understood. In this article, we describe a clinically translatable topical, neuroprotective treatment (recombinant human nerve growth factor, rh-NGF) predominantly targeting secondary degeneration in a pONT rat model. Topical application of rh-NGF twice daily for 3 weeks significantly improves RGC survival as shown by reduced RGC apoptosis in vivo and increased RGC population in the inferior retina, which is predominantly affected in this model by secondary degeneration. Topical rh-NGF also promotes greater axonal survival and inhibits astrocyte activity in the optic nerve. Collectively, these results suggest that topical rh-NGF exhibits neuroprotective effects on retinal neurons via influencing secondary degeneration process. As topical rh-NGF is already involved in early clinical trials, this highlights its potential in multiple indications in patients, including those affected by glaucomatous optic neuropathy.
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Affiliation(s)
- Li Guo
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom.
| | - Benjamin M Davis
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Nivedita Ravindran
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Joana Galvao
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Neel Kapoor
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Nasrin Haamedi
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Ehtesham Shamsher
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Vy Luong
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom
| | - Elena Fico
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom.,Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, L'Aquila, Italy
| | - M Francesca Cordeiro
- Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom. .,Western Eye Hospital, Imperial College Healthcare NHS Trust, London, United Kingdom.
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15
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Takemura H, Ogawa S, Mezer AA, Horiguchi H, Miyazaki A, Matsumoto K, Shikishima K, Nakano T, Masuda Y. Diffusivity and quantitative T1 profile of human visual white matter tracts after retinal ganglion cell damage. NEUROIMAGE-CLINICAL 2019; 23:101826. [PMID: 31026624 PMCID: PMC6482365 DOI: 10.1016/j.nicl.2019.101826] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 03/27/2019] [Accepted: 04/13/2019] [Indexed: 02/04/2023]
Abstract
In patients with retinal ganglion cell diseases, recent diffusion tensor imaging (DTI) studies have revealed structural abnormalities in visual white matter tracts such as the optic tract, and optic radiation. However, the microstructural origin of these diffusivity changes is unknown as DTI metrics involve multiple biological factors and do not correlate directly with specific microstructural properties. In contrast, recent quantitative T1 (qT1) mapping methods provide tissue property measurements relatively specific to myelin volume fractions in white matter. This study aims to improve our understanding of microstructural changes in visual white matter tracts following retinal ganglion cell damage in Leber's hereditary optic neuropathy (LHON) patients by combining DTI and qT1 measurements. We collected these measurements from seven LHON patients and twenty age-matched control subjects. For all individuals, we identified the optic tract and the optic radiation using probabilistic tractography, and evaluated diffusivity and qT1 profiles along them. Both diffusivity and qT1 measurements in the optic tract differed significantly between LHON patients and controls. In the optic radiation, these changes were observed in diffusivity but were not evident in qT1 measurements. This suggests that myelin loss may not explain trans-synaptic diffusivity changes in the optic radiation as a consequence of retinal ganglion cell disease. Retinal ganglion cell damage affects diffusivity and T1 along visual pathways. DTI metric identified white matter change in both optic tract and optic radiation. T1 measurement in optic radiation did not exhibit abnormality, unlike DTI metric. Myelin loss may not be a major cause of diffusivity change along optic radiation.
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Affiliation(s)
- Hiromasa Takemura
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology, and Osaka University, Suita, Japan; Graduate School of Frontier Biosciences, Osaka University, Suita, Japan.
| | - Shumpei Ogawa
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan; Department of Ophthalmology, Atsugi city hospital, Atsugi, Japan.
| | - Aviv A Mezer
- The Edmond and Lily Safra Center for Brain Science, The Hebrew University of Jerusalem, Israel
| | - Hiroshi Horiguchi
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | | | - Kenji Matsumoto
- Brain Science Institute, Tamagawa University, Machida, Japan
| | - Keigo Shikishima
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Tadashi Nakano
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Yoichiro Masuda
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
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16
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Yoshimine S, Ogawa S, Horiguchi H, Terao M, Miyazaki A, Matsumoto K, Tsuneoka H, Nakano T, Masuda Y, Pestilli F. Age-related macular degeneration affects the optic radiation white matter projecting to locations of retinal damage. Brain Struct Funct 2018; 223:3889-3900. [PMID: 29951918 DOI: 10.1007/s00429-018-1702-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 06/17/2018] [Indexed: 12/16/2022]
Abstract
We investigated the impact of age-related macular degeneration (AMD) on visual acuity and the visual white matter. We combined an adaptive cortical atlas and diffusion-weighted magnetic resonance imaging (dMRI) and tractography to separate optic radiation (OR) projections to different retinal eccentricities in human primary visual cortex. We exploited the known anatomical organization of the OR and clinically relevant data to segment the OR into three primary components projecting to fovea, mid- and far-periphery. We measured white matter tissue properties-fractional anisotropy, linearity, planarity, sphericity-along the aforementioned three components of the optic radiation to compare AMD patients and controls. We found differences in white matter properties specific to OR white matter fascicles projecting to primary visual cortex locations corresponding to the location of retinal damage (fovea). Additionally, we show that the magnitude of white matter properties in AMD patients' correlates with visual acuity. In sum, we demonstrate a specific relation between visual loss, anatomical location of retinal damage and white matter damage in AMD patients. Importantly, we demonstrate that these changes are so profound that can be detected using magnetic resonance imaging data with clinical resolution. The conserved mapping between retinal and white matter damage suggests that retinal neurodegeneration might be a primary cause of white matter degeneration in AMD patients. The results highlight the impact of eye disease on brain tissue, a process that may become an important target to monitor during the course of treatment.
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Affiliation(s)
- Shoyo Yoshimine
- Department of Ophthalmology, The Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo, 105-8461, Japan.
| | - Shumpei Ogawa
- Department of Ophthalmology, The Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo, 105-8461, Japan.,Department of Ophthalmology, Atsugi City Hospital, Kanagawa, Japan
| | - Hiroshi Horiguchi
- Department of Ophthalmology, The Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Masahiko Terao
- Research Institute for Time Studies, Yamaguchi University, Yamaguchi, Japan
| | | | - Kenji Matsumoto
- Tamagawa University Brain Science Institute, Machida, Tokyo, Japan
| | - Hiroshi Tsuneoka
- Department of Ophthalmology, The Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Tadashi Nakano
- Department of Ophthalmology, The Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Yoichiro Masuda
- Department of Ophthalmology, The Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo, 105-8461, Japan
| | - Franco Pestilli
- Department of Psychological and Brain Sciences, Indiana Network Science Institute, Indiana University, Bloomington, IN, 47405, USA. .,Department of Computer Science, Indiana University, Bloomington, USA. .,Department of Intelligent Systems Engineering, Indiana University, Bloomington, USA. .,Program in Neuroscience, Indiana University, Bloomington, USA. .,Program in Cognitive Science, Indiana University, Bloomington, USA. .,School of Optometry, Indiana University, Bloomington, USA.
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17
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Zhang X, Guo X, Zhang N, Cai H, Sun J, Wang Q, Qi Y, Zhang L, Yang L, Shi FD, Yu C. Cerebral Blood Flow Changes in Multiple Sclerosis and Neuromyelitis Optica and Their Correlations With Clinical Disability. Front Neurol 2018; 9:305. [PMID: 29780351 PMCID: PMC5946009 DOI: 10.3389/fneur.2018.00305] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 04/18/2018] [Indexed: 11/13/2022] Open
Abstract
Distinguishing relapsing-remitting multiple sclerosis (RRMS) and neuromyelitis optica (NMO) is clinically important because they differ in prognosis and treatment. This study aimed to identify perfusion abnormalities in RRMS and NMO and their correlations with gray matter volume (GMV) atrophy and clinical parameters. Structural and arterial spin labeling MRI scans were performed in 39 RRMS patients, 62 NMO patients, and 73 healthy controls. The gray matter cerebral blood flow (CBF) values were voxel-wisely compared among the three groups with and without GMV correction. The regional CBF changes were correlated with the Expanded Disability Status Scale scores in the corresponding patient groups. Although multiple brain regions showed CBF differences among the three groups without GMV correction, only three of these regions remained significant after GMV correction. Specifically, both the RRMS and NMO groups showed reduced CBF in the occipital cortex and increased CBF in the right putamen compared to the control group. The RRMS group had increased CBF only in the medial prefrontal cortex compared to the other two groups. The occipital CBF was negatively correlated with clinical disability in the NMO group; however, the CBF in the right putamen was positively correlated with clinical disability in both patient groups. These findings suggest that there are perfusion alterations independent of GMV atrophy in RRMS and NMO patients. The regional CBF in the occipital cortex and putamen could be used as imaging features to objectively assess clinical disability in these patients.
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Affiliation(s)
- Xue Zhang
- Department of Radiology, Tianjin Key Laboratory of Functional Imaging, Tianjin, China
| | - Xi Guo
- Department of Radiology, Tianjin Key Laboratory of Functional Imaging, Tianjin, China
| | - Ningnannan Zhang
- Department of Radiology, Tianjin Key Laboratory of Functional Imaging, Tianjin, China
| | - Huanhuan Cai
- Laboratory of Digital Medical Imaging, Medical Imaging Center, The First Affiliated Hospital, Anhui University of Chinese Medicine, Hefei, China
| | - Jie Sun
- Department of Radiology, Tianjin Key Laboratory of Functional Imaging, Tianjin, China
| | - Qiuhui Wang
- Department of Radiology, Tianjin Key Laboratory of Functional Imaging, Tianjin, China
| | - Yuan Qi
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China
| | - Linjie Zhang
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China
| | - Li Yang
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China
| | - Fu-Dong Shi
- Department of Neurology, Tianjin Medical University General Hospital, Tianjin, China
| | - Chunshui Yu
- Department of Radiology, Tianjin Key Laboratory of Functional Imaging, Tianjin, China
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18
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Quantitative assessment of optic nerve in patients with Leber’s hereditary optic neuropathy using reduced field-of-view diffusion tensor imaging. Eur J Radiol 2017; 93:24-29. [DOI: 10.1016/j.ejrad.2017.05.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 05/21/2017] [Indexed: 11/22/2022]
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19
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Majander A, Robson AG, João C, Holder GE, Chinnery PF, Moore AT, Votruba M, Stockman A, Yu-Wai-Man P. The pattern of retinal ganglion cell dysfunction in Leber hereditary optic neuropathy. Mitochondrion 2017; 36:138-149. [PMID: 28729193 PMCID: PMC5644721 DOI: 10.1016/j.mito.2017.07.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 07/02/2017] [Accepted: 07/14/2017] [Indexed: 02/07/2023]
Abstract
Leber inherited optic neuropathy (LHON) is characterized by subacute bilateral loss of central vision due to dysfunction and loss of retinal ganglion cells (RGCs). Comprehensive visual electrophysiological investigations (including pattern reversal visual evoked potentials, pattern electroretinography and the photopic negative response) performed on 13 patients with acute and chronic LHON indicate early impairment of RGC cell body function and severe axonal dysfunction. Temporal, spatial and chromatic psychophysical tests performed on 7 patients with acute LHON and 4 patients with chronic LHON suggest severe involvement or loss of the midget, parasol and bistratified RGCs associated with all three principal visual pathways.
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Affiliation(s)
- A Majander
- UCL Institute of Ophthalmology, London, UK; Moorfields Eye Hospital, London, UK; Department of Ophthalmology, University of Helsinki, Helsinki University Hospital, Helsinki, Finland.
| | - A G Robson
- UCL Institute of Ophthalmology, London, UK; Moorfields Eye Hospital, London, UK
| | - C João
- UCL Institute of Ophthalmology, London, UK
| | - G E Holder
- UCL Institute of Ophthalmology, London, UK; Moorfields Eye Hospital, London, UK
| | - P F Chinnery
- MRC-Mitochondrial Biology Unit, Cambridge Biomedical Campus, Cambridge, UK; Department of Clinical Neurosciences, Cambridge Biomedical Campus, University of Cambridge, Cambridge, UK
| | - A T Moore
- UCL Institute of Ophthalmology, London, UK; Moorfields Eye Hospital, London, UK; Ophthalmology Department, UCSF School of Medicine, San Francisco, CA, United States
| | - M Votruba
- School of Optometry and Vision Sciences, Cardiff University, and Cardiff Eye Unit, University Hospital Wales, Cardiff, UK
| | - A Stockman
- UCL Institute of Ophthalmology, London, UK
| | - P Yu-Wai-Man
- UCL Institute of Ophthalmology, London, UK; Moorfields Eye Hospital, London, UK; Department of Clinical Neurosciences, Cambridge Biomedical Campus, University of Cambridge, Cambridge, UK; Wellcome Trust Centre for Mitochondrial Research, Newcastle University, and Newcastle Eye Centre, Royal Victoria Infirmary, Newcastle upon Tyne, UK.
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20
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21
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Serial Diffusion Tensor Imaging of the Optic Radiations after Acute Optic Neuritis. J Ophthalmol 2016; 2016:2764538. [PMID: 27555964 PMCID: PMC4983385 DOI: 10.1155/2016/2764538] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 07/06/2016] [Accepted: 07/10/2016] [Indexed: 12/13/2022] Open
Abstract
Previous studies have reported diffusion tensor imaging (DTI) changes within the optic radiations of patients after optic neuritis (ON). We aimed to study optic radiation DTI changes over 12 months following acute ON and to study correlations between DTI parameters and damage to the optic nerve and primary visual cortex (V1). We measured DTI parameters [fractional anisotropy (FA), axial diffusivity (AD), radial diffusivity (RD), and mean diffusivity (MD)] from the optic radiations of 38 acute ON patients at presentation and 6 and 12 months after acute ON. In addition, we measured retinal nerve fibre layer thickness, visual evoked potential amplitude, optic radiation lesion load, and V1 thickness. At baseline, FA was reduced and RD and MD were increased compared to control. Over 12 months, FA reduced in patients at an average rate of −2.6% per annum (control = −0.51%; p = 0.006). Change in FA, RD, and MD correlated with V1 thinning over 12 months (FA: R = 0.450, p = 0.006; RD: R = −0.428, p = 0.009; MD: R = −0.365, p = 0.029). In patients with no optic radiation lesions, AD significantly correlated with RNFL thinning at 12 months (R = 0.489, p = 0.039). In conclusion, DTI can detect optic radiation changes over 12 months following acute ON that correlate with optic nerve and V1 damage.
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22
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Gueven N, Nadikudi M, Daniel A, Chhetri J. Targeting mitochondrial function to treat optic neuropathy. Mitochondrion 2016; 36:7-14. [PMID: 27476756 DOI: 10.1016/j.mito.2016.07.013] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 01/03/2023]
Abstract
Many reports have illustrated a tight connection between vision and mitochondrial function. Not only are most mitochondrial diseases associated with some form of vision impairment, many ophthalmological disorders such as glaucoma, age-related macular degeneration and diabetic retinopathy also show signs of mitochondrial dysfunction. Despite a vast amount of evidence, vision loss is still only treated symptomatically, which is only partially a consequence of resistance to acknowledge that mitochondria could be the common denominator and hence a promising therapeutic target. More importantly, clinical support of this concept is only emerging. Moreover, only a few drug candidates and treatment strategies are in development or approved that selectively aim to restore mitochondrial function. This review rationalizes the currently developed therapeutic approaches that target mitochondrial function by discussing their proposed mode(s) of action and provides an overview on their development status with regards to optic neuropathies.
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Affiliation(s)
- Nuri Gueven
- Pharmacy, School of Medicine, University of Tasmania, Hobart, TAS, Australia.
| | - Monila Nadikudi
- Pharmacy, School of Medicine, University of Tasmania, Hobart, TAS, Australia
| | - Abraham Daniel
- Pharmacy, School of Medicine, University of Tasmania, Hobart, TAS, Australia
| | - Jamuna Chhetri
- Pharmacy, School of Medicine, University of Tasmania, Hobart, TAS, Australia
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Abstract
INTRODUCTION Mitochondria, essential to multicellular life, convert food into ATP to satisfy cellular energy demands. Since different tissues have different energy requirements, mitochondrial density is high in tissues with high metabolic needs, such as the visual system, which is therefore highly susceptible to limited energy supply as a result of mitochondrial dysfunction. AREAS COVERED Vision impairment is a common feature of most mitochondrial diseases. At the same time, there is mounting evidence that mitochondrial impairment contributes to the pathogenesis of major eye diseases such as glaucoma and might also be involved in the reported vision impairment in neurodegenerative disorders such as Alzheimer's disease. EXPERT OPINION Rather than relying on symptomatic treatment, acknowledging the mitochondrial origin of visual disorders in mitochondrial, neurodegenerative and ocular diseases could lead to novel therapeutics that aim to modulate mitochondrial function in order to protect against vision loss. This approach has already shown some promising clinical results in inherited retinal disorders, which supports the idea that targeting mitochondria could also be a treatment option for other optic neuropathies.
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Affiliation(s)
- Jamuna Chhetri
- a Division of Pharmacy, School of Medicine, Faculty of Health , University of Tasmania , Hobart , Australia
| | - Nuri Gueven
- a Division of Pharmacy, School of Medicine, Faculty of Health , University of Tasmania , Hobart , Australia
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Distributed abnormalities of brain white matter architecture in patients with dominant optic atrophy and OPA1 mutations. J Neurol 2015; 262:1216-27. [DOI: 10.1007/s00415-015-7696-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 02/27/2015] [Accepted: 02/27/2015] [Indexed: 01/08/2023]
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Manners DN, Rizzo G, La Morgia C, Tonon C, Testa C, Barboni P, Malucelli E, Valentino ML, Caporali L, Strobbe D, Carelli V, Lodi R. Diffusion Tensor Imaging Mapping of Brain White Matter Pathology in Mitochondrial Optic Neuropathies. AJNR Am J Neuroradiol 2015; 36:1259-65. [PMID: 25792533 DOI: 10.3174/ajnr.a4272] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 12/05/2014] [Indexed: 01/04/2023]
Abstract
BACKGROUND AND PURPOSE Brain white matter is frequently affected in mitochondrial diseases; optic atrophy gene 1-autosomal dominant optic atrophy and Leber hereditary optic neuropathy are the most frequent mitochondrial monosymptomatic optic neuropathies. In this observational study, brain white matter microstructure was characterized by DTI in patients with optic atrophy gene 1-autosomal dominant optic atrophy and Leber hereditary optic neuropathy, in relation to clinical and genetic features. MATERIALS AND METHODS Nineteen patients with optic atrophy gene 1-autosomal dominant optic atrophy and 17 with Leber hereditary optic neuropathy older than 18 years of age, all genetically diagnosed, and 19 healthy volunteers underwent DTI by using a 1.5T MR imaging scanner and neurologic and ophthalmologic assessments. Brain white matter DTI metrics were calculated for all participants, and, in patients, their correlations with genetics and clinical findings were calculated. RESULTS Compared with controls, patients with optic atrophy gene 1-autosomal dominant optic atrophy had an increased mean diffusivity in 29.2% of voxels analyzed within major white matter tracts distributed throughout the brain, while fractional anisotropy was reduced in 30.3% of voxels. For patients with Leber hereditary optic neuropathy, the proportion of altered voxels was only 0.5% and 5.5%, respectively, of which half was found within the optic radiation and 3.5%, in the smaller acoustic radiation. In almost all regions, fractional anisotropy diminished with age in patients with optic atrophy gene 1-autosomal dominant optic atrophy and correlated with average retinal nerve fiber layer thickness in several areas. Mean diffusivity increased in those with a missense mutation. Patients with Leber hereditary optic neuropathy taking idebenone had slightly milder changes. CONCLUSIONS Patients with Leber hereditary optic neuropathy had preferential involvement of the optic and acoustic radiations, consistent with trans-synaptic degeneration, whereas patients with optic atrophy gene 1-autosomal dominant optic atrophy presented with widespread involvement suggestive of a multisystemic, possibly a congenital/developmental, disorder. White matter changes in Leber hereditary optic neuropathy and optic atrophy gene 1-autosomal dominant optic atrophy may be exploitable as biomarkers.
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Affiliation(s)
- D N Manners
- From the Functional MR Unit (D.N.M., G.R., C.Tonon, C.Testa, R.L.)
| | - G Rizzo
- From the Functional MR Unit (D.N.M., G.R., C.Tonon, C.Testa, R.L.) Neurology Unit (G.R., C.L.M., M.L.V., L.C., D.S., V.C.), Department of Biomedical and NeuroMotor Sciences
| | - C La Morgia
- Neurology Unit (G.R., C.L.M., M.L.V., L.C., D.S., V.C.), Department of Biomedical and NeuroMotor Sciences "Istituto di Ricovero e Cura a Carattere Scientifico Istituto delle Scienze Neurologiche di Bologna" (C.L.M., M.L.V., L.C., D.S., V.C.), Bologna, Italy
| | - C Tonon
- From the Functional MR Unit (D.N.M., G.R., C.Tonon, C.Testa, R.L.)
| | - C Testa
- From the Functional MR Unit (D.N.M., G.R., C.Tonon, C.Testa, R.L.)
| | - P Barboni
- Studio Oculistico d'Azeglio (P.B.), Bologna, Italy
| | - E Malucelli
- Department of Pharmacy and Biotechnology (E.M.), University of Bologna, Bologna, Italy
| | - M L Valentino
- Neurology Unit (G.R., C.L.M., M.L.V., L.C., D.S., V.C.), Department of Biomedical and NeuroMotor Sciences "Istituto di Ricovero e Cura a Carattere Scientifico Istituto delle Scienze Neurologiche di Bologna" (C.L.M., M.L.V., L.C., D.S., V.C.), Bologna, Italy
| | - L Caporali
- Neurology Unit (G.R., C.L.M., M.L.V., L.C., D.S., V.C.), Department of Biomedical and NeuroMotor Sciences "Istituto di Ricovero e Cura a Carattere Scientifico Istituto delle Scienze Neurologiche di Bologna" (C.L.M., M.L.V., L.C., D.S., V.C.), Bologna, Italy
| | - D Strobbe
- Neurology Unit (G.R., C.L.M., M.L.V., L.C., D.S., V.C.), Department of Biomedical and NeuroMotor Sciences "Istituto di Ricovero e Cura a Carattere Scientifico Istituto delle Scienze Neurologiche di Bologna" (C.L.M., M.L.V., L.C., D.S., V.C.), Bologna, Italy
| | - V Carelli
- Neurology Unit (G.R., C.L.M., M.L.V., L.C., D.S., V.C.), Department of Biomedical and NeuroMotor Sciences "Istituto di Ricovero e Cura a Carattere Scientifico Istituto delle Scienze Neurologiche di Bologna" (C.L.M., M.L.V., L.C., D.S., V.C.), Bologna, Italy
| | - R Lodi
- From the Functional MR Unit (D.N.M., G.R., C.Tonon, C.Testa, R.L.)
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Nucci C, Martucci A, Cesareo M, Garaci F, Morrone LA, Russo R, Corasaniti MT, Bagetta G, Mancino R. Links among glaucoma, neurodegenerative, and vascular diseases of the central nervous system. PROGRESS IN BRAIN RESEARCH 2015; 221:49-65. [DOI: 10.1016/bs.pbr.2015.04.010] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Direct optic nerve sheath (DONS) application of Schwann cells prolongs retinal ganglion cell survival in vivo. Cell Death Dis 2014; 5:e1460. [PMID: 25321467 PMCID: PMC4237238 DOI: 10.1038/cddis.2014.399] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 08/06/2014] [Accepted: 08/08/2014] [Indexed: 01/10/2023]
Abstract
Cell-based therapies are increasingly recognized as a potential strategy to treat retinal neurodegenerative disease. Their administration, however, is normally indirect and complex, often with an inability to assess in real time their effects on cell death and their migration/integration into the host retina. In the present study, using a partial optic nerve transection (pONT) rat model, we describe a new method of Schwann cell (SC) delivery (direct application to injured optic nerve sheath, SC/DONS), which was compared with intravitreal SC delivery (SC/IVT). Both SC/DONS and SC/IVT were able to be assessed in vivo using imaging to visualize retinal ganglion cell (RGC) apoptosis and SC retinal integration. RGC death in the pONT model was best fitted to the one-phase exponential decay model. Although both SC/DONS and SC/IVT altered the temporal course of RGC degeneration in pONT, SC/DONS resulted in delayed but long-lasting effects on RGC protection, compared with SC/IVT treatment. In addition, their effects on primary and secondary degeneration, and axonal regeneration, were also investigated, by histology, whole retinal counting, and modelling of RGC loss. SC/DONS was found to significantly reduce RGC apoptosis in vivo and significantly increase RGC survival by targeting secondary rather than primary degeneration. Both SC/DONS and SC/IVT were found to promote RGC axonal regrowth after optic nerve injury, with evidence of GAP-43 expression in RGC somas and axons. SC/DONS may have the potential in the treatment of optic neuropathies, such as glaucoma. We show that SC transplantation can be monitored in real time and that the protective effects of SCs are associated with targeting secondary degeneration, with implications for translating cell-based therapies to the clinic.
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Ogawa S, Takemura H, Horiguchi H, Terao M, Haji T, Pestilli F, Yeatman JD, Tsuneoka H, Wandell BA, Masuda Y. White matter consequences of retinal receptor and ganglion cell damage. Invest Ophthalmol Vis Sci 2014; 55:6976-86. [PMID: 25257055 DOI: 10.1167/iovs.14-14737] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Patients with Leber hereditary optic neuropathy (LHON) and cone-rod dystrophy (CRD) have central vision loss; but CRD damages the retinal photoreceptor layer, and LHON damages the retinal ganglion cell (RGC) layer. Using diffusion MRI, we measured how these two types of retinal damage affect the optic tract (ganglion cell axons) and optic radiation (geniculo-striate axons). METHODS Adult onset CRD (n = 5), LHON (n = 6), and healthy controls (n = 14) participated in the study. We used probabilistic fiber tractography to identify the optic tract and the optic radiation. We compared axial and radial diffusivity at many positions along the optic tract and the optic radiation. RESULTS In both types of patients, diffusion measures within the optic tract and the optic radiation differ from controls. The optic tract change is principally a decrease in axial diffusivity; the optic radiation change is principally an increase in radial diffusivity. CONCLUSIONS Both photoreceptor layer (CRD) and retinal ganglion cell (LHON) retinal disease causes substantial change in the visual white matter. These changes can be measured using diffusion MRI. The diffusion changes measured in the optic tract and the optic radiation differ, suggesting that they are caused by different biological mechanisms.
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Affiliation(s)
- Shumpei Ogawa
- Department of Psychology, Stanford University, Stanford, California, United States Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Hiromasa Takemura
- Department of Psychology, Stanford University, Stanford, California, United States Department of Psychology, The University of Tokyo, Tokyo, Japan
| | - Hiroshi Horiguchi
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Masahiko Terao
- Department of Psychology, The University of Tokyo, Tokyo, Japan Tamagawa University Brain Science Institute, Machida, Japan
| | - Tomoki Haji
- Department of Ophthalmology, Atsugi City Hospital, Kanagawa, Japan
| | - Franco Pestilli
- Department of Psychology, Stanford University, Stanford, California, United States
| | - Jason D Yeatman
- Department of Psychology, Stanford University, Stanford, California, United States
| | - Hiroshi Tsuneoka
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan
| | - Brian A Wandell
- Department of Psychology, Stanford University, Stanford, California, United States
| | - Yoichiro Masuda
- Department of Ophthalmology, The Jikei University School of Medicine, Tokyo, Japan The Japan Society for the Promotion of Science, Tokyo, Japan
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Sánchez-Catasús CA, Cabrera-Gomez J, Almaguer Melián W, Giroud Benítez JL, Rodríguez Rojas R, Bayard JB, Galán L, Sánchez RG, Fuentes NP, Valdes-Sosa P. Brain Tissue Volumes and Perfusion Change with the Number of Optic Neuritis Attacks in Relapsing Neuromyelitis Optica: A Voxel-Based Correlation Study. PLoS One 2013; 8:e66271. [PMID: 23824339 PMCID: PMC3688888 DOI: 10.1371/journal.pone.0066271] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 05/03/2013] [Indexed: 12/16/2022] Open
Abstract
Recent neuroimaging studies show that brain abnormalities in neuromyelitis optica (NMO) are more frequent than earlier described. Yet, more research considering multiple aspects of NMO is necessary to better understand these abnormalities. A clinical feature of relapsing NMO (RNMO) is that the incremental disability is attack-related. Therefore, association between the attack-related process and neuroimaging might be expected. On the other hand, the immunopathological analysis of NMO lesions has suggested that CNS microvasculature could be an early disease target, which could alter brain perfusion. Brain tissue volume changes accompanying perfusion alteration could also be expected throughout the attack-related process. The aim of this study was to investigate in RNMO patients, by voxel-based correlation analysis, the assumed associations between regional brain white (WMV) and grey matter volumes (GMV) and/or perfusion on one side, and the number of optic neuritis (ON) attacks, myelitis attacks and/or total attacks on the other side. For this purpose, high resolution T1-weighted MRI and perfusion SPECT imaging were obtained in 15 RNMO patients. The results showed negative regional correlations of WMV, GMV and perfusion with the number of ON attacks, involving important components of the visual system, which could be relevant for the comprehension of incremental visual disability in RNMO. We also found positive regional correlation of perfusion with the number of ON attacks, mostly overlapping the brain area where the WMV showed negative correlation. This provides evidence that brain microvasculature is an early disease target and suggests that perfusion alteration could be important in the development of brain structural abnormalities in RNMO.
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