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Kaçar S, Coric D, Ometto G, Montesano G, Denniston AK, Keane PA, Uitdehaag BMJ, Crabb DP, Schoonheim MM, Petzold A, Strijbis EMM. Exploring Vitreous Haze as a Potential Biomarker for Accelerated Glymphatic Outflow and Neurodegeneration in Multiple Sclerosis: A Cross-Sectional Study. Brain Sci 2023; 14:36. [PMID: 38248251 PMCID: PMC10813039 DOI: 10.3390/brainsci14010036] [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] [Received: 11/09/2023] [Revised: 12/08/2023] [Accepted: 12/25/2023] [Indexed: 01/23/2024] Open
Abstract
BACKGROUND The glymphatic system removes neurodegenerative debris. The ocular glymphatic outflow is from the eye to the proximal optic nerve. In multiple sclerosis (MS), atrophy of the optic nerve increases the glymphatic outflow space. Here, we tested whether vitreous haze (VH) can provide novel insights into the relationship between neurodegeneration and the ocular glymphatic system in MS. METHODS This cross-sectional study comprised 315 persons with MS and 87 healthy controls (HCs). VH was quantified from optical coherence tomography (OCT) volume scans. Neurodegeneration was determined on three-dimensional T1 (3DT1) MRI, lesion detection on fluid-attenuated inversion (FLAIR), and layer thickness on OCT. Generalized estimating equations, corrected for age, were used to analyze associations between VH and metrics for neurodegeneration, demographics, and clinical scales. Group differences were determined between mild, moderate, and severe disability. RESULTS On the group level, VH scores were comparable between MS and control (p = 0.629). In MS, VH scores declined with disease duration (β = -0.009, p = 0.004) and age (β = -0.007, p = 0.001). There was no relation between VH scores and higher age in HCs. In MS patients, VH was related to normalized gray (NGMV, β = 0.001, p = 0.011) and white matter volume (NWMV, β = 0.001, p = 0.003), macular ganglion cell-inner plexiform layer thickness (mGCIPL, β = 0.006, p < 0.001), and peripapillary retinal nerve fiber layer thickness (pRNFL, β = 0.004, p = 0.008). VH was significantly lower in severe compared to mild disability (mean difference -28.86%, p = 0.058). CONCLUSIONS There is a correlation between VH on OCT and disease duration, more severe disability and lower brain volumes in MS. Biologically, these relationships suggest accelerated glymphatic clearance with disease-related atrophy.
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Affiliation(s)
- Sezgi Kaçar
- MS Center Amsterdam, Neurology, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, VU University Medical Center, Amsterdam UMC Location VUmc, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands; (D.C.); (B.M.J.U.); (A.P.); (E.M.M.S.)
- Dutch Expertise Center for Neuro-Ophthalmology, VU University Medical Center, 1081 HV Amsterdam, The Netherlands
| | - Danko Coric
- MS Center Amsterdam, Neurology, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, VU University Medical Center, Amsterdam UMC Location VUmc, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands; (D.C.); (B.M.J.U.); (A.P.); (E.M.M.S.)
- Dutch Expertise Center for Neuro-Ophthalmology, VU University Medical Center, 1081 HV Amsterdam, The Netherlands
| | - Giovanni Ometto
- Department of Optometry and Visual Sciences, City, University of London, London WC1E 7HU, UK; (G.O.); (G.M.); (D.P.C.)
| | - Giovanni Montesano
- Department of Optometry and Visual Sciences, City, University of London, London WC1E 7HU, UK; (G.O.); (G.M.); (D.P.C.)
| | - Alastair K. Denniston
- Academic Unit of Ophthalmology, Institute of Inflammation and Ageing, University of Birmingham, Birmingham B15 2TT, UK;
- Department of Ophthalmology, University Hospitals Birmingham NHS Foundation Trust, Birmingham B15 2TT, UK
- NIHR Biomedical Research Centre, Moorfields Eye Hospital and UCL Institute of Ophthalmology, London EC1V 9LF, UK;
| | - Pearse A. Keane
- NIHR Biomedical Research Centre, Moorfields Eye Hospital and UCL Institute of Ophthalmology, London EC1V 9LF, UK;
| | - Bernard M. J. Uitdehaag
- MS Center Amsterdam, Neurology, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, VU University Medical Center, Amsterdam UMC Location VUmc, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands; (D.C.); (B.M.J.U.); (A.P.); (E.M.M.S.)
| | - David P. Crabb
- Department of Optometry and Visual Sciences, City, University of London, London WC1E 7HU, UK; (G.O.); (G.M.); (D.P.C.)
| | - Menno M. Schoonheim
- Department of Anatomy and Neurosciences, Neuroscience Campus Amsterdam, VU University Medical Center, 1081 HV Amsterdam, The Netherlands;
| | - Axel Petzold
- MS Center Amsterdam, Neurology, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, VU University Medical Center, Amsterdam UMC Location VUmc, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands; (D.C.); (B.M.J.U.); (A.P.); (E.M.M.S.)
- Dutch Expertise Center for Neuro-Ophthalmology, VU University Medical Center, 1081 HV Amsterdam, The Netherlands
- Department of Neurology and Ophthalmology, Moorfields Eye Hospital, City Road, London EC1V 9LF, UK
- The National Hospital for Neurology and Neurosurgery, University College London, London WC1E 7HU, UK
| | - Eva M. M. Strijbis
- MS Center Amsterdam, Neurology, Vrije Universiteit Amsterdam, Amsterdam Neuroscience, VU University Medical Center, Amsterdam UMC Location VUmc, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands; (D.C.); (B.M.J.U.); (A.P.); (E.M.M.S.)
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Olatunji R, Lim TR, Jones B, Tafur M, Mathur S, Lin AW, Bharatha A, Suthiphosuwan S. Delayed Gadolinium Leakage in Ocular Structures on Brain MR Imaging: Prevalence and Associated Factors. AJNR Am J Neuroradiol 2023; 45:90-95. [PMID: 38123939 PMCID: PMC10756574 DOI: 10.3174/ajnr.a8073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 10/25/2023] [Indexed: 12/23/2023]
Abstract
BACKGROUND AND PURPOSE Gadolinium leakage in ocular structures (GLOS) is characterized by hyperintense signal in the chambers of the eye on FLAIR and has been reported in association with blood-ocular barrier breakdown in patients with ischemic strokes. The underlying mechanism of GLOS remains poorly understood; however, some studies suggest it may be part of a physiologic excretion pathway of gadolinium. This study aimed to determine the prevalence of GLOS in an unselected patient population. MATERIALS AND METHODS A retrospective analysis was conducted on 439 patients who underwent brain MR imaging within 7 days of receiving a gadolinium-based contrast agent injection for a prior MR imaging study. Clinical, imaging, and laboratory data were collected. Descriptive and logistic regression analyses were performed. RESULTS GLOS was observed in 26 of 439 patients (6%). The occurrence of GLOS varied with time, with 3 (12%), 14 (54%), 8 (31%), and 1 (4%) patient showing GLOS within 24, 25-72, 73-120, and >120 hours after gadolinium-based contrast agent injection, respectively. Patients with GLOS were older (median age: 72 versus 55 years, P = .001) and had higher median serum creatinine levels (73 versus 64 µmol/L, P = .005) and a lower median estimated glomerular filtration rate (84 versus 101 mL/min/1.73 m2, P < .001). A shorter median time interval between gadolinium-based contrast agent injection and the index brain MR imaging was observed in the group positive for GLOS (62 versus 91 hours, P = .003). Multivariable regression analysis identified the estimated glomerular filtration rate (OR = 0.970; 95% CI, 0.049-0.992; P = .008) and time interval since gadolinium-based contrast agent injection (OR = 0.987; 95% CI, 0.977-0.997; P = .012) as independent factors associated with GLOS. CONCLUSIONS GLOS was observed in only a small percentage of patients receiving gadolinium-based contrast agent within 7 days before brain MR imaging. This phenomenon was noted in patients with normal findings on brain MR imaging and those with various CNS pathologies, and it was associated with lower estimated glomerular filtration rates and shorter time intervals after gadolinium-based contrast agent injection. While GLOS may be a physiologic gadolinium-based contrast agent excretion pathway, the presence of ocular disease was not formally evaluated in the included population. Awareness of GLOS is nonetheless useful for appropriate radiologic interpretation.
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Affiliation(s)
- Richard Olatunji
- From the Division of Diagnostic Neuroradiology (R.O., T.R.L., S.M., A.W.L., A.B., S.S.), Department of Medical Imaging, St. Michael's Hospital, Unity Health Toronto, University of Toronto, Toronto, Ontario, Canada
- Department of Radiology (R.O.), University College Hospital, University of Ibadan, Ibadan, Nigeria
| | - Timothy Reynold Lim
- From the Division of Diagnostic Neuroradiology (R.O., T.R.L., S.M., A.W.L., A.B., S.S.), Department of Medical Imaging, St. Michael's Hospital, Unity Health Toronto, University of Toronto, Toronto, Ontario, Canada
| | - Blair Jones
- Department of Data Science (B.J.), St. Michael's Hospital, Unity Health Toronto, University of Toronto, Toronto, Ontario, Canada
| | - Monica Tafur
- Division of Abdominal and Breast Imaging (M.T.), Department of Medical Imaging, St. Michael's Hospital, Unity Health Toronto, University of Toronto, Toronto, Ontario, Canada
| | - Shobhit Mathur
- From the Division of Diagnostic Neuroradiology (R.O., T.R.L., S.M., A.W.L., A.B., S.S.), Department of Medical Imaging, St. Michael's Hospital, Unity Health Toronto, University of Toronto, Toronto, Ontario, Canada
- Medical Imaging Office of Research & Innovation (S.M.), Li Ka Shing Knowledge Institute, Toronto, Ontario, Canada
| | - Amy W Lin
- From the Division of Diagnostic Neuroradiology (R.O., T.R.L., S.M., A.W.L., A.B., S.S.), Department of Medical Imaging, St. Michael's Hospital, Unity Health Toronto, University of Toronto, Toronto, Ontario, Canada
| | - Aditya Bharatha
- From the Division of Diagnostic Neuroradiology (R.O., T.R.L., S.M., A.W.L., A.B., S.S.), Department of Medical Imaging, St. Michael's Hospital, Unity Health Toronto, University of Toronto, Toronto, Ontario, Canada
| | - Suradech Suthiphosuwan
- From the Division of Diagnostic Neuroradiology (R.O., T.R.L., S.M., A.W.L., A.B., S.S.), Department of Medical Imaging, St. Michael's Hospital, Unity Health Toronto, University of Toronto, Toronto, Ontario, Canada
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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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4
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Sims JR, Chen AM, Sun Z, Deng W, Colwell NA, Colbert MK, Zhu J, Sainulabdeen A, Faiq MA, Bang JW, Chan KC. Role of Structural, Metabolic, and Functional MRI in Monitoring Visual System Impairment and Recovery. J Magn Reson Imaging 2021; 54:1706-1729. [PMID: 33009710 PMCID: PMC8099039 DOI: 10.1002/jmri.27367] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 08/24/2020] [Accepted: 08/27/2020] [Indexed: 12/13/2022] Open
Abstract
The visual system, consisting of the eyes and the visual pathways of the brain, receives and interprets light from the environment so that we can perceive the world around us. A wide variety of disorders can affect human vision, ranging from ocular to neurologic to systemic in nature. While other noninvasive imaging techniques such as optical coherence tomography and ultrasound can image particular sections of the visual system, magnetic resonance imaging (MRI) offers high resolution without depth limitations. MRI also gives superior soft-tissue contrast throughout the entire pathway compared to computed tomography. By leveraging different imaging sequences, MRI is uniquely capable of unveiling the intricate processes of ocular anatomy, tissue physiology, and neurological function in the human visual system from the microscopic to macroscopic levels. In this review we discuss how structural, metabolic, and functional MRI can be used in the clinical assessment of normal and pathologic states in the anatomic structures of the visual system, including the eyes, optic nerves, optic chiasm, optic tracts, visual brain nuclei, optic radiations, and visual cortical areas. We detail a selection of recent clinical applications of MRI at each position along the visual pathways, including the evaluation of pathology, plasticity, and the potential for restoration, as well as its limitations and key areas of ongoing exploration. Our discussion of the current and future developments in MR ocular and neuroimaging highlights its potential impact on our ability to understand visual function in new detail and to improve our protection and treatment of anatomic structures that are integral to this fundamental sensory system. LEVEL OF EVIDENCE 3: TECHNICAL EFFICACY STAGE 3: .
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Affiliation(s)
- Jeffrey R. Sims
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, USA
| | - Anna M. Chen
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, USA
- Sackler Institute of Graduate Biomedical Sciences, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, USA
| | - Zhe Sun
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, USA
- Sackler Institute of Graduate Biomedical Sciences, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, USA
| | - Wenyu Deng
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, USA
| | - Nicole A. Colwell
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, USA
| | - Max K. Colbert
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, USA
| | - Jingyuan Zhu
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, USA
- Department of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Anoop Sainulabdeen
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, USA
- Department of Surgery and Radiology, College of Veterinary and Animal Sciences, Kerala Veterinary and Animal Sciences University, Thrissur, India
| | - Muneeb A. Faiq
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, USA
| | - Ji Won Bang
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, USA
| | - Kevin C. Chan
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, USA
- Sackler Institute of Graduate Biomedical Sciences, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, USA
- Department of Radiology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, USA
- Neuroscience Institute, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, New York, USA
- Center for Neural Science, College of Arts and Science, New York University, New York, New York, USA
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5
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Mahan VL. Effects of lactate and carbon monoxide interactions on neuroprotection and neuropreservation. Med Gas Res 2021; 11:158-173. [PMID: 34213499 PMCID: PMC8374456 DOI: 10.4103/2045-9912.318862] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 08/21/2020] [Accepted: 10/23/2020] [Indexed: 11/04/2022] Open
Abstract
Lactate, historically considered a waste product of anerobic metabolism, is a metabolite in whole-body metabolism needed for normal central nervous system (CNS) functions and a potent signaling molecule and hormone in the CNS. Neuronal activity signals normally induce its formation primarily in astrocytes and production is dependent on anerobic and aerobic metabolisms. Functions are dependent on normal dynamic, expansive, and evolving CNS functions. Levels can change under normal physiologic conditions and with CNS pathology. A readily combusted fuel that is sshuttled throughout the body, lactate is used as an energy source and is needed for CNS hemostasis, plasticity, memory, and excitability. Diffusion beyond the neuron active zone impacts activity of neurons and astrocytes in other areas of the brain. Barriergenesis, function of the blood-brain barrier, and buffering between oxidative metabolism and glycolysis and brain metabolism are affected by lactate. Important to neuroprotection, presence or absence is associated with L-lactate and heme oxygenase/carbon monoxide (a gasotransmitter) neuroprotective systems. Effects of carbon monoxide on L-lactate affect neuroprotection - interactions of the gasotransmitter with L-lactate are important to CNS stability, which will be reviewed in this article.
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Affiliation(s)
- Vicki L. Mahan
- Department of Surgery and Pediatrics, Drexel University College of Medicine, Philadelphia, PA, USA
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Abstract
Optic nerve health is essential for proper function of the visual system. However, the pathophysiology of certain neurodegenerative disease processes affecting the optic nerve, such as glaucoma, is not fully understood. Recently, it was hypothesized that a lack of proper clearance of neurotoxins contributes to neurodegenerative diseases. The ability to clear metabolic waste is essential for tissue homeostasis in mammals, including humans. While the brain lacks the traditional lymphatic drainage system identified in other anatomical regions, there is growing evidence of a glymphatic system in the central nervous system, which structurally includes the optic nerve. Named to acknowledge the supportive role of astroglial cells, this perivascular fluid drainage system is essential to remove toxic metabolites from the central nervous system. Herein, we review existing literature describing the physiology and dysfunction of the glymphatic system specifically as it relates to the optic nerve. We summarize key imaging studies demonstrating the existence of a glymphatic system in the optic nerves of wild-type rodents, aquaporin 4-null rodents, and humans; glymphatic imaging studies in diseases where the optic nerve is impaired; and current evidence regarding pharmacological and lifestyle interventions that may help promote glymphatic function to improve optic nerve health. We conclude by highlighting future research directions that could be applied to improve imaging detection and guide therapeutic interventions for diseases affecting the optic nerve.
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Affiliation(s)
- Anisha Kasi
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, NY, USA
| | - Crystal Liu
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, NY, USA
| | - Muneeb A Faiq
- Department of Ophthalmology, NYU Grossman School of Medicine, NYU Langone Health, New York University, New York, NY, USA
| | - Kevin C Chan
- Department of Ophthalmology; Department of Radiology; Neuroscience Institute, NYU Grossman School of Medicine, NYU Langone Health; Center for Neural Science, College of Arts and Science, New York University, New York, NY, USA
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7
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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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8
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In vivo MRI evaluation of early postnatal development in normal and impaired rat eyes. Sci Rep 2021; 11:15513. [PMID: 34330952 PMCID: PMC8324881 DOI: 10.1038/s41598-021-93991-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Accepted: 07/01/2021] [Indexed: 11/08/2022] Open
Abstract
This study employed in vivo 7-T magnetic resonance imaging (MRI) to evaluate the postnatal ocular growth patterns under normal development or neonatal impairments in Sprague-Dawley rats. Using T2-weighted imaging on healthy rats from postnatal day (P) 1 (newborn) to P60 (adult), the volumes of the anterior chamber and posterior chamber (ACPC), lens, and vitreous humor increased logistically with ACPC expanding by 33-fold and the others by fivefold. Intravitreal potassium dichromate injection at P1, P7, and P14 led to T1-weighted signal enhancement in the developing retina by 188-289%. Upon unilateral hypoxic-ischemic encephalopathy at P7, monocular deprivation at P15, and monocular enucleation at P1, T2-weighted imaging of the adult rats showed decreased ocular volumes to different extents. In summary, in vivo high-field MRI allows for non-invasive evaluation of early postnatal development in the normal and impaired rat eyes. Chromium-enhanced MRI appeared effective in examining the developing retina before natural eyelid opening at P14 with relevance to lipid metabolism. The reduced ocular volumes upon neonatal visual impairments provided evidence to the emerging problems of why some impaired visual outcomes cannot be solely predicted by neurological assessments and suggested the need to look into both the eye and the brain under such conditions.
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Vanhove M, Wagner JM, Noppen B, Jonckx B, Vermassen E, Stitt AW. Systemic exposure following intravitreal administration of therapeutic agents: an integrated pharmacokinetic approach. 2. THR-687. J Pharmacokinet Pharmacodyn 2021; 48:837-849. [PMID: 34302261 PMCID: PMC8604881 DOI: 10.1007/s10928-021-09774-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 07/07/2021] [Indexed: 11/28/2022]
Abstract
Intravitreal (IVT) injection remains the preferred administration route of pharmacological agents intended for the treatment of back of the eye diseases such as diabetic macular edema (DME) and neovascular age-related macular degeneration (nvAMD). The procedure enables drugs to be delivered locally at high concentrations whilst limiting whole body exposure and associated risk of systemic adverse events. Nevertheless, intravitreally-delivered drugs do enter the general circulation and achieving an accurate understanding of systemic exposure is pivotal for the evaluation and development of drugs administered in the eye. We report here the full pharmacokinetic properties of THR-687, a pan RGD integrin antagonist currently in clinical development for the treatment of DME, in both rabbit and minipig. Pharmacokinetic characterization included description of vitreal elimination, of systemic pharmacokinetics, and of systemic exposure following IVT administration. For the latter, we present a novel pharmacokinetic model that assumes clear partition between the vitreous humor compartment itself where the drug is administered and the central systemic compartment. We also propose an analytical solution to the system of differential equations that represent the pharmacokinetic model, thereby allowing data analysis with standard nonlinear regression analysis. The model accurately describes circulating levels of THR-687 following IVT administration in relevant animal models, and we suggest that this approach is relevant to a range of drugs and analysis of subsequent systemic exposure.
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Affiliation(s)
- Marc Vanhove
- Oxurion N.V, Gaston Geenslaan 1, 3001, leuven, Belgium.
| | - Jean-Marc Wagner
- Haute École de la Province de Liège, Avenue Montesquieu 6, 4101, Seraing, Belgium
| | | | - Bart Jonckx
- Oxurion N.V, Gaston Geenslaan 1, 3001, leuven, Belgium
| | | | - Alan W Stitt
- Oxurion N.V, Gaston Geenslaan 1, 3001, leuven, Belgium
- Centre for Experimental Medicine, Queen's University Belfast, Belfast, Northern Ireland, UK
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10
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Wu H, Luo B, Yuan G, Wang Q, Liu P, Zhao Y, Zhai L, Ma Y, Lv W, Zhang J. The diagnostic value of the IDEAL-T2WI sequence in dysthyroid optic neuropathy: a quantitative analysis of the optic nerve and cerebrospinal fluid in the optic nerve sheath. Eur Radiol 2021; 31:7419-7428. [PMID: 33993334 DOI: 10.1007/s00330-021-08030-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 04/05/2021] [Accepted: 04/29/2021] [Indexed: 12/22/2022]
Abstract
OBJECTIVES To evaluate the optic nerve and CSF in the optic nerve sheath as imaging markers of dysthyroid optic neuropathy (DON). METHODS In this single-centre retrospective study, orbital images of 30 consecutive participants (54 orbits) with DON, 30 patients (60 orbits) with thyroid-associated ophthalmopathy (TAO) without DON, and 19 healthy controls (HCs; 38 orbits) were analysed. The diameter and cross-sectional area of the optic nerve and its sheath, water fraction of the optic nerve, and volume of the fluid in the optic nerve sheath were measured and compared. The associations between MR parameters and clinical measures were assessed using correlation analysis. RESULTS The diameter and water fraction of the optic nerve (3 mm and 6 mm behind the eyeball), optic nerve subarachnoid space (ONSS) (3 mm and 6 mm behind the eyeball), and subarachnoid fluid volume in the optic nerve sheath were significantly greater in the DON group than in the TAO group (p < 0.01) or HC group (p < 0.01). ROC analysis showed that ONSS 3 mm behind the eyeball (ONSS3) was a robust predictor of DON (AUC = 0.957, sensitivity = 0.907, specificity = 0.9). Water fraction of the optic nerve 3 mm behind the eyeball (water fraction3) had the best specificity (0.967). Water fraction3, fluid volume in the optic nerve sheath, and optic nerve diameter (3 mm behind the eyeball) were correlated with clinical measures (i.e. clinical activity score, mean defect, and pattern standard deviation). CONCLUSIONS Increased water fraction of the optic nerve and ONSS3 are promising and easily accessible radiological markers for diagnosing DON. KEY POINTS • The water fraction of the optic nerve and optic nerve subarachnoid space (ONSS) are greater in patients with dysthyroid optic neuropathy (DON) than in patients with thyroid-associated ophthalmopathy (TAO) without DON. • The optic nerve and the cerebrospinal fluid in the optic nerve sheath measures are associated with visual dysfunction. • The water fraction of the optic nerve and ONSS may be promising imaging markers for diagnosing DON.
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Affiliation(s)
- Hongyu Wu
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Ban Luo
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Gang Yuan
- Department of Endocrinology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Qiuxia Wang
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Ping Liu
- Department of Medical Imaging, Guangdong Second Provincial General Hospital, Guangzhou, China
| | - Yali Zhao
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Linhan Zhai
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China
| | - Yanqiang Ma
- Ultrasound Medical Center, Lanzhou University Sencond Hospital, Lanzhou University, Lanzhou, 730030, Gansu, China
| | - Wenzhi Lv
- Department of Artificial Intelligence, Julei Technology Company, Wuhan, 430030, Hubei, China
| | - Jing Zhang
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, Hubei, China.
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11
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Ganau M, Iqbal M, Ligarotti GKI, Syrmos N. Breakthrough in the assessment of cerebral perfusion and vascular permeability after brain trauma through the adoption of dynamic indocyanine green-enhanced near-infrared spectroscopy. Quant Imaging Med Surg 2020; 10:2081-2084. [PMID: 33141119 DOI: 10.21037/qims-20-905] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Mario Ganau
- Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford University, UK
| | - Mohammad Iqbal
- Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford University, UK
| | | | - Nikolaos Syrmos
- Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
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