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Lohia K, Soans RS, Saxena R, Mahajan K, Gandhi TK. Distinct rich and diverse clubs regulate coarse and fine binocular disparity processing: Evidence from stereoscopic task-based fMRI. iScience 2024; 27:109831. [PMID: 38784010 PMCID: PMC11111836 DOI: 10.1016/j.isci.2024.109831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 03/07/2024] [Accepted: 04/24/2024] [Indexed: 05/25/2024] Open
Abstract
While cortical regions involved in processing binocular disparities have been studied extensively, little is known on how the human visual system adapts to changing disparity magnitudes. In this paper, we investigate causal mechanisms of coarse and fine binocular disparity processing using fMRI with a clinically validated, custom anaglyph-based stimulus. We make use of Granger causality and graph measures to reveal the existence of distinct rich and diverse clubs across different disparity magnitudes. We demonstrate that Middle Temporal area (MT) plays a specialized role with overlapping rich and diverse characteristics. Next, we show that subtle interhemispheric differences exist across various brain regions, despite an overall right hemisphere dominance. Finally, we pass the graph measures through the decision tree and found that the diverse clubs outperform rich clubs in decoding disparity magnitudes. Our study sets the stage for conducting further investigations on binocular disparity processing, particularly in the context of neuro-ophthalmic disorders with binocular impairments.
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Affiliation(s)
- Kritika Lohia
- Department of Electrical Engineering, Indian Institute of Technology – Delhi, New Delhi, India
| | - Rijul Saurabh Soans
- Department of Electrical Engineering, Indian Institute of Technology – Delhi, New Delhi, India
- Laboratory of Experimental Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
- Herbert Wertheim School of Optometry and Vision Science, University of California, Berkeley, Berkeley, CA, USA
| | - Rohit Saxena
- Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | | | - Tapan K. Gandhi
- Department of Electrical Engineering, Indian Institute of Technology – Delhi, New Delhi, India
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Wang H, Yan X, Zhang Q, Wu Q, Qiu L, Zhou J, Guo P. Altered small-world and disrupted topological properties of functional connectivity networks in patients with nonarteritic anterior ischemic optic neuropathy. Clin Neurol Neurosurg 2024; 236:108101. [PMID: 38176218 DOI: 10.1016/j.clineuro.2023.108101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Accepted: 12/22/2023] [Indexed: 01/06/2024]
Abstract
BACKGROUND Nonarteritic anterior ischemic optic neuropathy (NAION) is a disease of the optic nerve, but its effect on brain network topology is still unclear.This study aimed to investigate brain network alterations in NAION patients and to explore their relationship with functional impairment. METHODS Resting-state functional MRI data were collected from 23 NAION patients and 23 matched healthy control subjects.We used graph theory analysis to investigate the global and nodal network topological properties,and network-based statistical (NBS) methods were used to explore intergroup differences in functional connectivity (FC) strength. RESULTS Compared to the control group, NAION patients had lower global efficiency, normalized clustering coefficient and small-world values and higher characteristic path length (P < 0.05). In the hub distributions of functional networks, the NAION group had one hub region disappearing and four hub regions appearing in nodal degree centrality (Dc), and two hubs disappearing and one hub region appearing in nodal betweenness centrality (Bc). The NAION group also had enhanced brain FC primarily associated with the frontal, prefrontal, parietal lobes and cerebellum. Furthermore, the right temporal pole, superior temporal gyrus (r = -0.424), the right inferior temporal gyrus (r = -0.414), the right cerebellar lobule Ⅵ (r = 0.450), and the left cerebellar lobule crus Ⅰ (r = 0.584) were significantly correlated with clinical severity. CONCLUSION NAION patients show disruption and redistribution of FC in specific regions of the brain network, which may be associated with visual impairment.
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Affiliation(s)
- Hui Wang
- Department of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Key Laboratory of Ophthalmology and Visual Sciences, Beijing 100730, China
| | - Xiaoling Yan
- Department of Ophthalmology, Dongfang Hospital, Beijing University of Chinese Medicine, Beijing 100078, China
| | - Qiuhuan Zhang
- Department of Radiology, Dongfang Hospital, Beijing University of Chinese Medicine, Beijing 100078, China
| | - Qiong Wu
- Department of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Key Laboratory of Ophthalmology and Visual Sciences, Beijing 100730, China
| | - Lixin Qiu
- Department of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Key Laboratory of Ophthalmology and Visual Sciences, Beijing 100730, China
| | - Jian Zhou
- Department of Ophthalmology, Dongfang Hospital, Beijing University of Chinese Medicine, Beijing 100078, China.
| | - Pengde Guo
- Department of Radiology, Dongfang Hospital, Beijing University of Chinese Medicine, Beijing 100078, China.
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Dong X, Liu L, Du X, Wang Y, Zhang P, Li Z, Bao M. Treating amblyopia using altered reality enhances the fine-scale functional correlations in early visual areas. Hum Brain Mapp 2023; 44:6499-6510. [PMID: 37929783 PMCID: PMC10681636 DOI: 10.1002/hbm.26526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 10/02/2023] [Accepted: 10/13/2023] [Indexed: 11/07/2023] Open
Abstract
Amblyopia is a developmental visual disorder that causes substantial visual deficits. Studies using resting-state functional magnetic resonance imaging have disclosed abnormal brain functional connectivity (FC) both across long-range cortical sites and within the visual cortex in amblyopes, which is considered to be related to impaired visual functions. However, little work has examined whether restoring the vision of amblyopes accompanies with an improvement of FC. Here in adult amblyopes and healthy participants, we compared their brain FC before and after an altered-reality adaptation training. Before the training, the voxel-wise FCs of amblyopia patients were substantially weaker than those of healthy control participants both within and across the early visual areas. After the training, visual acuities improved in amblyopes but not in the control participants. The effect kept strengthening in the subsequent month without further adaptation. Importantly, we observed enhanced voxel-wise FC both within and across the early visual areas of amblyopes. Moreover, the enhancement continued for at least 1 month. These results suggest that the effective treatment can improve both the amblyopes' vision and functional connections in the visual cortex.
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Affiliation(s)
- Xue Dong
- CAS Key Laboratory of Behavioral Science, Institute of PsychologyChinese Academy of SciencesBeijingChina
- Department of PsychologyUniversity of Chinese Academy of SciencesBeijingChina
| | - Lijuan Liu
- Beijing Institute of Ophthalmology, Beijing Tongren HospitalCapital Medical UniversityBeijingChina
| | - Xinxin Du
- CAS Key Laboratory of Behavioral Science, Institute of PsychologyChinese Academy of SciencesBeijingChina
- Department of PsychologyUniversity of Chinese Academy of SciencesBeijingChina
| | - Yue Wang
- State Key Laboratory of Brain and Cognitive Science, Institute of BiophysicsChinese Academy of SciencesBeijingChina
| | - Peng Zhang
- State Key Laboratory of Brain and Cognitive Science, Institute of BiophysicsChinese Academy of SciencesBeijingChina
| | - Zhihao Li
- School of PsychologyShenzhen UniversityShenzhenGuangdongChina
- Department of Psychiatry and Behavioral SciencesEmory UniversityAtlantaGeorgiaUSA
| | - Min Bao
- CAS Key Laboratory of Behavioral Science, Institute of PsychologyChinese Academy of SciencesBeijingChina
- Department of PsychologyUniversity of Chinese Academy of SciencesBeijingChina
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Wang Y, Wu Y, Luo L, Li F. Structural and functional alterations in the brains of patients with anisometropic and strabismic amblyopia: a systematic review of magnetic resonance imaging studies. Neural Regen Res 2023; 18:2348-2356. [PMID: 37282452 PMCID: PMC10360096 DOI: 10.4103/1673-5374.371349] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023] Open
Abstract
Amblyopia is the most common cause of vision loss in children and can persist into adulthood in the absence of effective intervention. Previous clinical and neuroimaging studies have suggested that the neural mechanisms underlying strabismic amblyopia and anisometropic amblyopia may be different. Therefore, we performed a systematic review of magnetic resonance imaging studies investigating brain alterations in patients with these two subtypes of amblyopia; this study is registered with PROSPERO (registration ID: CRD42022349191). We searched three online databases (PubMed, EMBASE, and Web of Science) from inception to April 1, 2022; 39 studies with 633 patients (324 patients with anisometropic amblyopia and 309 patients with strabismic amblyopia) and 580 healthy controls met the inclusion criteria (e.g., case-control designed, peer-reviewed articles) and were included in this review. These studies highlighted that both strabismic amblyopia and anisometropic amblyopia patients showed reduced activation and distorted topological cortical activated maps in the striate and extrastriate cortices during task-based functional magnetic resonance imaging with spatial-frequency stimulus and retinotopic representations, respectively; these may have arisen from abnormal visual experiences. Compensations for amblyopia that are reflected in enhanced spontaneous brain function have been reported in the early visual cortices in the resting state, as well as reduced functional connectivity in the dorsal pathway and structural connections in the ventral pathway in both anisometropic amblyopia and strabismic amblyopia patients. The shared dysfunction of anisometropic amblyopia and strabismic amblyopia patients, relative to controls, is also characterized by reduced spontaneous brain activity in the oculomotor cortex, mainly involving the frontal and parietal eye fields and the cerebellum; this may underlie the neural mechanisms of fixation instability and anomalous saccades in amblyopia. With regards to specific alterations of the two forms of amblyopia, anisometropic amblyopia patients suffer more microstructural impairments in the precortical pathway than strabismic amblyopia patients, as reflected by diffusion tensor imaging, and more significant dysfunction and structural loss in the ventral pathway. Strabismic amblyopia patients experience more attenuation of activation in the extrastriate cortex than in the striate cortex when compared to anisometropic amblyopia patients. Finally, brain structural magnetic resonance imaging alterations tend to be lateralized in the adult anisometropic amblyopia patients, and the patterns of brain alterations are more limited in amblyopic adults than in children. In conclusion, magnetic resonance imaging studies provide important insights into the brain alterations underlying the pathophysiology of amblyopia and demonstrate common and specific alterations in anisometropic amblyopia and strabismic amblyopia patients; these alterations may improve our understanding of the neural mechanisms underlying amblyopia.
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Affiliation(s)
- Yuxia Wang
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan Province, China
| | - Ye Wu
- Department of Ophthalmology, Laboratory of Optometry and Vision Sciences, West China Hospital/West China School of Medicine, Sichuan University, Chengdu, Sichuan Province, China
| | - Lekai Luo
- Department of Radiology, West China Second Hospital of Sichuan University, Chengdu, Sichuan Province, China
| | - Fei Li
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan Province, China
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Meng C, Zhang Y, Wang S. Anisometropic amblyopia: A review of functional and structural changes and treatment. Eur J Ophthalmol 2023; 33:1529-1535. [PMID: 36448184 DOI: 10.1177/11206721221143164] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
Amblyopia is the decreased best-corrected visual acuity (BCVA) in one or both eyes caused by the abnormal processing of visual input during development. One common cause of amblyopia is anisometropia, which has attracted widespread attention. Many structural changes occur in the primary and extrastriate visual areas of the cerebral cortex, as well as in the eyes, in patients with anisometropic amblyopia. Understanding these mechanisms has provided a favorable theoretical basis for treating anisometropic amblyopia. This article reviews the functional and anatomical changes and progress toward the treatment of anisometropic amblyopia.
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Affiliation(s)
- Can Meng
- Corneal Refraction Department, The Second Hospital of Jilin University, Changchun, China
| | - Yan Zhang
- Corneal Refraction Department, The Second Hospital of Jilin University, Changchun, China
| | - Shurong Wang
- Corneal Refraction Department, The Second Hospital of Jilin University, Changchun, China
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Liu F, Wang ZH, Huang W, Xu Y, Sang X, Liu R, Li ZY, Bi YL, Tang L, Peng JY, Wei JR, Miao ZC, Yan JH, Liu S, Yan JH, Liu S. Defects and asymmetries in the visual pathway of non-human primates with natural strabismus and amblyopia. Zool Res 2023; 44:153-168. [PMID: 36484227 PMCID: PMC9841183 DOI: 10.24272/j.issn.2095-8137.2022.254] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Strabismus and amblyopia are common ophthalmologic developmental diseases caused by abnormal visual experiences. However, the underlying pathogenesis and visual defects are still not fully understood. Most studies have used experimental interference to establish disease-associated animal models, while ignoring the natural pathophysiological mechanisms. This study was designed to investigate whether natural strabismus and amblyopia are associated with abnormal neurological defects. We screened one natural strabismic monkey ( Macaca fascicularis) and one natural amblyopic monkey from hundreds of monkeys, and retrospectively analyzed one human strabismus case. Neuroimaging, behavioral, neurophysiological, neurostructural, and genovariation features were systematically evaluated using magnetic resonance imaging (MRI), behavioral tasks, flash visual evoked potentials (FVEP), electroretinogram (ERG), optical coherence tomography (OCT), and whole-genome sequencing (WGS), respectively. Results showed that the strabismic patient and natural strabismic and amblyopic monkeys exhibited similar abnormal asymmetries in brain structure, i.e., ipsilateral impaired right hemisphere. Visual behavior, visual function, retinal structure, and fundus of the monkeys were impaired. Aberrant asymmetry in binocular visual function and structure between the strabismic and amblyopic monkeys was closely related, with greater impairment of the left visual pathway. Several similar known mutant genes for strabismus and amblyopia were also identified. In conclusion, natural strabismus and amblyopia are accompanied by abnormal asymmetries of the visual system, especially visual neurophysiological and neurostructural defects. Our results suggest that future therapeutic and mechanistic studies should consider defects and asymmetries throughout the entire visual system.
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Affiliation(s)
- Feng Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Zhong-Hao Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Wanjing Huang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Ying Xu
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, Guangdong 510632, China
| | - Xuan Sang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Ruifeng Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Zhou-Yue Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Ya-Lan Bi
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus, Cambridge CB10 1SD, UK
| | - Lei Tang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Jing-Yi Peng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Jia-Ru Wei
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China
| | - Zhi-Chao Miao
- European Molecular Biology Laboratory, European Bioinformatics Institute (EMBL-EBI), Wellcome Genome Campus, Cambridge CB10 1SD, UK,Translational Research Institute of Brain and Brain-Like Intelligence and Department of Anesthesiology, Shanghai Fourth People’s Hospital Affiliated to Tongji University School of Medicine, Shanghai 200081, China
| | - Jian-Hua Yan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China,E-mail:
| | - Sheng Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, Guangdong 510060, China,Guangdong Province Key Laboratory of Brain Function and Disease, Guangzhou, Guangdong 510080, China,
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Wang G, Liu L. Amblyopia: progress and promise of functional magnetic resonance imaging. Graefes Arch Clin Exp Ophthalmol 2022; 261:1229-1246. [PMID: 36282454 DOI: 10.1007/s00417-022-05826-z] [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: 12/28/2021] [Revised: 08/14/2022] [Accepted: 09/02/2022] [Indexed: 11/28/2022] Open
Abstract
Amblyopia is a neurodevelopmental disorder characterized by functional deficits in the visual cortex. Functional magnetic resonance imaging (fMRI) is the most commonly used neuroimaging technique for investigating amblyopia. Herein, we systematically searched a PubMed database from inception to December 2021 to highlight the current progress and promises about fMRI technology in amblyopia; amblyopia's neural mechanism, the comparison of different types of amblyopia, and the evaluation of the therapeutic effect were explored. Relevant articles published in English and appropriate cross-references were considered for inclusion, including basic studies, imaging techniques, clinical diagnostic and therapeutic studies, case series, and reviews.
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Affiliation(s)
- Guiqu Wang
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, 610041, China
| | - Longqian Liu
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, 610041, China.
- Department of Optometry and Visual Science, West China Hospital, Sichuan University, Chengdu, 610041, China.
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Sujanthan S, Shmuel A, Mendola JD. Resting-state functional MRI of the visual system for characterization of optic neuropathy. Front Hum Neurosci 2022; 16:943618. [PMID: 36330314 PMCID: PMC9622755 DOI: 10.3389/fnhum.2022.943618] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 09/15/2022] [Indexed: 11/23/2022] Open
Abstract
Optic neuropathy refers to disease of the optic nerve and can result in loss of visual acuity and/or visual field defects. Combining findings from multiple fMRI modalities can offer valuable information for characterizing and managing optic neuropathies. In this article, we review a subset of resting-state functional magnetic resonance imaging (RS-fMRI) studies of optic neuropathies. We consider glaucoma, acute optic neuritis (ON), discuss traumatic optic neuropathy (TON), and explore consistency between findings from RS and visually driven fMRI studies. Consistent with visually driven studies, glaucoma studies at rest also indicated reduced activation in the visual cortex and dorsal visual stream. RS-fMRI further reported varying levels of functional connectivity in the ventral stream depending on disease severity. ON patients show alterations within the visual cortex in both fMRI techniques. Particularly, higher-than-normal RS activity is observed in the acute phase and decreases as the disease progresses. A similar pattern is observed in the visual cortex of TON-like, open globe injury (OGI), patients. Additionally, visually driven and RS-fMRI studies of ON patients show recovery of brain activity in the visual cortex. RS-fMRI suggests recovery of signals in higher-tier visual areas MT and LOC as well. Finally, RS-fMRI has not yet been applied to TON, although reviewing OGI studies suggests that it is feasible. Future RS-fMRI studies of optic neuropathies could prioritize studying the fine scale RS activity of brain areas that visually driven studies have identified. We suggest that a more systematic longitudinal comparison of optic neuropathies with advanced fMRI would provide improved diagnostic and prognostic information.
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Affiliation(s)
- Sujeevini Sujanthan
- Department of Ophthalmology & Visual Sciences, McGill University, Montreal, QC, Canada
- *Correspondence: Sujeevini Sujanthan,
| | - Amir Shmuel
- Departments of Neurology, Neurosurgery, Physiology, and Biomedical Engineering, McGill University, Montreal, QC, Canada
- Montreal Neurological Institute, McGill University, Montreal, QC, Canada
- Amir Shmuel,
| | - Janine Dale Mendola
- Department of Ophthalmology & Visual Sciences, McGill University, Montreal, QC, Canada
- Janine Dale Mendola,
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Chen X, Liao M, Jiang P, Sun H, Liu L, Gong Q. Abnormal effective connectivity in visual cortices underlies stereopsis defects in amblyopia. Neuroimage Clin 2022; 34:103005. [PMID: 35421811 PMCID: PMC9011166 DOI: 10.1016/j.nicl.2022.103005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 02/15/2022] [Accepted: 04/05/2022] [Indexed: 02/08/2023]
Abstract
Abnormal effective connectivity inherent stereopsis defects in amblyopia was studied. A weakened connection from V2v to LO2 relates to stereopsis defects in amblyopia. Higher-order visual cortices may serve as key nodes to the stereopsis defects. An independent longitudinal dataset was used to validate the obtained results.
The neural basis underlying stereopsis defects in patients with amblyopia remains unclear, which hinders the development of clinical therapy. This study aimed to investigate visual network abnormalities in patients with amblyopia and their associations with stereopsis function. Spectral dynamic causal modeling methods were employed for resting-state functional magnetic resonance imaging data to investigate the effective connectivity (EC) among 14 predefined regions of interest in the dorsal and ventral visual pathways. We adopted two independent datasets, including a cross-sectional and a longitudinal dataset. In the cross-sectional dataset, we compared group differences in EC between 31 patients with amblyopia (mean age: 26.39 years old) and 31 healthy controls (mean age: 25.71 years old) and investigated the association between EC and stereoacuity. In addition, we explored EC changes after perceptual learning in a novel longitudinal dataset including 9 patients with amblyopia (mean age: 15.78 years old). We found consistent evidence from the two datasets indicating that the aberrant EC from V2v to LO2 is crucial for the stereoscopic deficits in the patients with amblyopia: it was weaker in the patients than in the controls, showed a positive linear relationship with the stereoscopic function, and increased after perceptual learning in the patients. In addition, higher-level dorsal (V3d, V3A, and V3B) and ventral areas (LO1 and LO2) were important nodes in the network of abnormal ECs associated with stereoscopic deficits in the patients with amblyopia. Our research provides insights into the neural mechanism underlying stereopsis deficits in patients with amblyopia and provides candidate targets for focused stimulus interventions to enhance the efficacy of clinical treatment for the improvement of stereopsis deficiency.
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Affiliation(s)
- Xia Chen
- Department of Optometry and Visual Science, West China Hospital, Sichuan University, Chengdu, China
| | - Meng Liao
- Department of Optometry and Visual Science, West China Hospital, Sichuan University, Chengdu, China; Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Ping Jiang
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, China; Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, Chengdu, China; Functional and Molecular Imaging Key Laboratory of Sichuan Province, Chengdu, China.
| | - Huaiqiang Sun
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, China; Imaging Research Core Facilities, West China Hospital of Sichuan University, Chengdu, Sichuan, China
| | - Longqian Liu
- Department of Optometry and Visual Science, West China Hospital, Sichuan University, Chengdu, China; Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China.
| | - Qiyong Gong
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, China; Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, Chengdu, China; Functional and Molecular Imaging Key Laboratory of Sichuan Province, Chengdu, China
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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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Huang H, Wang Y, Zhang L, Zhang Q, Wu X, He H. Psychological disorders of patients with allergic rhinitis in Chengdu, China: Exploratory Research (Preprint). JMIR Form Res 2022; 6:e37101. [DOI: 10.2196/37101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 09/13/2022] [Accepted: 09/27/2022] [Indexed: 11/13/2022] Open
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12
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Dai P, Zhou X, Ou Y, Xiong T, Zhang J, Chen Z, Zou B, Wei X, Wu Y, Xiao M. Altered Effective Connectivity of Children and Young Adults With Unilateral Amblyopia: A Resting-State Functional Magnetic Resonance Imaging Study. Front Neurosci 2021; 15:657576. [PMID: 34295218 PMCID: PMC8290343 DOI: 10.3389/fnins.2021.657576] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Accepted: 05/21/2021] [Indexed: 01/02/2023] Open
Abstract
The altered functional connectivity (FC) in amblyopia has been investigated by many studies, but the specific causality of brain connectivity needs to be explored further to understand the brain activity of amblyopia. We investigated whether the effective connectivity (EC) of children and young adults with amblyopia was altered. The subjects included 16 children and young adults with left eye amblyopia and 17 healthy controls (HCs). The abnormalities between the left/right primary visual cortex (PVC) and the other brain regions were investigated in a voxel-wise manner using the Granger causality analysis (GCA). According to the EC results in the HCs and the distribution of visual pathways, 12 regions of interest (ROIs) were selected to construct an EC network. The alteration of the EC network of the children and young adults with amblyopia was analyzed. In the voxel-wise manner analysis, amblyopia showed significantly decreased EC between the left/right of the PVC and the left middle frontal gyrus/left inferior frontal gyrus compared with the HCs. In the EC network analysis, compared with the HCs, amblyopia showed significantly decreased EC from the left calcarine fissure, posterior cingulate gyrus, left lingual gyrus, right lingual gyrus, and right fusiform gyrus to the right calcarine fissure. Amblyopia also showed significantly decreased EC from the right inferior frontal gyrus and right lingual gyrus to the left superior temporal gyrus compared with the HCs in the EC network analysis. The results may indicate that amblyopia altered the visual feedforward and feedback pathway, and amblyopia may have a greater relevance with the feedback pathway than the feedforward pathway. Amblyopia may also correlate with the feedforward of the third visual pathway.
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Affiliation(s)
- Peishan Dai
- School of Computer Science and Engineering, Central South University, Changsha, China.,Hunan Engineering Research Center of Machine Vision and Intelligent Medicine, Central South University, Changsha, China
| | - Xiaoyan Zhou
- School of Computer Science and Engineering, Central South University, Changsha, China.,Hunan Engineering Research Center of Machine Vision and Intelligent Medicine, Central South University, Changsha, China
| | - Yilin Ou
- School of Computer Science and Engineering, Central South University, Changsha, China.,Hunan Engineering Research Center of Machine Vision and Intelligent Medicine, Central South University, Changsha, China
| | - Tong Xiong
- School of Computer Science and Engineering, Central South University, Changsha, China.,Hunan Engineering Research Center of Machine Vision and Intelligent Medicine, Central South University, Changsha, China
| | - Jinlong Zhang
- School of Computer Science and Engineering, Central South University, Changsha, China.,Hunan Engineering Research Center of Machine Vision and Intelligent Medicine, Central South University, Changsha, China
| | - Zailiang Chen
- School of Computer Science and Engineering, Central South University, Changsha, China.,Hunan Engineering Research Center of Machine Vision and Intelligent Medicine, Central South University, Changsha, China
| | - Beiji Zou
- School of Computer Science and Engineering, Central South University, Changsha, China.,Hunan Engineering Research Center of Machine Vision and Intelligent Medicine, Central South University, Changsha, China
| | - Xin Wei
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha, China.,Hunan Clinical Research Center of Ophthalmic Disease, Changsha, China
| | - Ying Wu
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha, China.,Hunan Clinical Research Center of Ophthalmic Disease, Changsha, China
| | - Manyi Xiao
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha, China.,Hunan Clinical Research Center of Ophthalmic Disease, Changsha, China
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13
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Zhang S, Gao GP, Shi WQ, Li B, Lin Q, Shu HY, Shao Y. Abnormal interhemispheric functional connectivity in patients with strabismic amblyopia: a resting-state fMRI study using voxel-mirrored homotopic connectivity. BMC Ophthalmol 2021; 21:255. [PMID: 34107904 PMCID: PMC8188699 DOI: 10.1186/s12886-021-02015-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Accepted: 05/13/2021] [Indexed: 11/11/2022] Open
Abstract
Background Previous studies have demonstrated that strabismus amblyopia can result in markedly brain function alterations. However, the differences in spontaneous brain activities of strabismus amblyopia (SA) patients still remain unclear. Therefore, the current study intended to employthe voxel-mirrored homotopic connectivity (VMHC) method to investigate the intrinsic brain activity changes in SA patients. Purpose To investigate the changes in cerebral hemispheric functional connections in patients with SA and their relationship with clinical manifestations using the VMHC method. Material and methods In the present study, a total of 17 patients with SA (eight males and nine females) and 17 age- and weight-matched healthy control (HC) groups were enrolled. Based on the VMHC method, all subjects were examined by functional magnetic resonance imaging. The functional interaction between cerebral hemispheres was directly evaluated. The Pearson’s correlation test was used to analyze the clinical features of patients with SA. In addition, their mean VMHC signal values and the receiver operating characteristic curve were used to distinguish patients with SA and HC groups. Results Compared with HC group, patients with SA had higher VMHC values in bilateral cingulum ant, caudate, hippocampus, and cerebellum crus 1. Moreover, the VMHC values of some regions were positively correlated with some clinical manifestations. In addition, receiver operating characteristic curves presented higher diagnostic value in these areas. Conclusion SA subjects showed abnormal brain interhemispheric functional connectivity in visual pathways, which might give some instructive information for understanding the neurological mechanisms of SA patients.
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Affiliation(s)
- Shuang Zhang
- Department of Ophthalmology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Gui-Ping Gao
- Department of Ophthalmology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Wen-Qing Shi
- Department of Ophthalmology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Biao Li
- Department of Ophthalmology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Qi Lin
- Department of Ophthalmology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Hui-Ye Shu
- Department of Ophthalmology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Yi Shao
- Department of Ophthalmology, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China.
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14
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Zhang T, Jiang Q, Xu F, Zhang R, Liu D, Guo D, Wu J, Wen Y, Wang X, Jiang W, Bi H. Alternation of Resting-State Functional Connectivity Between Visual Cortex and Hypothalamus in Guinea Pigs With Experimental Glucocorticoid Enhanced Myopia After the Treatment of Electroacupuncture. Front Neuroinform 2021; 14:579769. [PMID: 33519409 PMCID: PMC7838498 DOI: 10.3389/fninf.2020.579769] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 12/07/2020] [Indexed: 12/12/2022] Open
Abstract
Excessive glucocorticoids (GC) may lead to the aggravation of several basic diseases including myopia, due to plasma hormone imbalances associated with the hypothalamic–pituitary–adrenal axis (HPAA). Electroacupuncture (EA) is an effective therapeutic method to treat many diseases, although it remains unclear whether EA at acupoints on the foot or back would be effective in treating eye diseases. It was recently found that visual cortex activity for responses to visual stimuli with spatial frequency and resting-state functional connectivity (FC) between the supramarginal gyrus and rostrolateral prefrontal cortex was significantly reduced in patients with high myopia. The present study aims to investigate the role of the alternation of resting-state FC among the bilateral visual cortex and hypothalamus in exerting anti-myopia effects of EA in GC-enhanced lens-induced myopic (LIM) guinea pigs such that the mechanisms of EA to treat GC-enhanced myopia at Shenshu (BL23) acupoints can be probed. To confirm the effects of EA, ocular parameters including axial length and GC-associated physiological parameters such as animal appearance, behavior, bodyweight, and levels of four HPAA-associated plasma hormones [free triiodothyronine (FT3), free thyroxine (FT4), estradiol (E2), and testosterone (T)] were also collected. Increased resting-state FC between the left and right visual cortex was detected in GC-enhanced lens-induced myopic guinea pigs with EA at BL23 acupoints (LIM+GC+EA) guinea pigs compared to GC-enhanced lens-induced myopic guinea pigs with EA at sham acupoints (LIM+GC+Sham) guinea pigs, as well as suppressed myopia and recovery of symptoms initially caused by overdose of GC. Recovered symptoms included improved animal appearance, behavior, bodyweight, and HPAA-associated plasma hormone levels were observed after 4 weeks of EA treatment. In contrast, the LIM+GC+Sham group showed decreased FC with elongation of axial length for myopization as compared to the control group and LIM group and exhibited a deterioration in physiological parameters including reduced body weight and balance disruption in the four measured HPAA-associated plasma hormones. Our findings suggest that EA could effectively treat GC-enhanced myopia by increasing resting-state FC between the left and right visual cortices, which may be pivotal to further understanding the application and mechanisms of EA in treating GC-enhanced myopia.
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Affiliation(s)
- Tao Zhang
- The First College of Clinical Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Qian Jiang
- Department of Ophthalmology and Optometry, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Furu Xu
- Department of Ophthalmology and Optometry, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Ruixue Zhang
- Department of Ophthalmology and Optometry, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Dezheng Liu
- Department of Ophthalmology and Optometry, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Dadong Guo
- Shandong Province Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Therapy of Ocular Disease, Eye Institute of Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Jianfeng Wu
- Department of Ophthalmology and Optometry, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Ying Wen
- Affiliated Eye Hospital of Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Xingrong Wang
- Affiliated Eye Hospital of Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Wenjun Jiang
- Shandong Province Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Therapy of Ocular Disease, Eye Institute of Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Hongsheng Bi
- Shandong Province Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Therapy of Ocular Disease, Eye Institute of Shandong University of Traditional Chinese Medicine, Jinan, China
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Levi DM. Amblyopia. HANDBOOK OF CLINICAL NEUROLOGY 2021; 178:13-30. [PMID: 33832673 DOI: 10.1016/b978-0-12-821377-3.00002-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Amblyopia is a neurodevelopmental abnormality that results in physiological alterations in the visual pathways and impaired vision in one eye, less commonly in both. It reflects a broad range of neural, perceptual, oculomotor, and clinical abnormalities that can occur when normal visual development is disrupted early in life. Aside from refractive error, amblyopia is the most common cause of vision loss in infants and young children. It causes a constellation of perceptual deficits in the vision of the amblyopic eye, including a loss of visual acuity, position acuity, and contrast sensitivity, particularly at high spatial frequencies, as well as increased internal noise and prolonged manual and saccadic reaction times. There are also perceptual deficits in the strong eye, such as certain types of motion perception, reflecting altered neural responses and functional connectivity in visual cortex (Ho et al., 2005). Treatment in young children consists of correction of any refractive error and patching of the strong eye. Compliance with patching is challenging and a substantial proportion of amblyopic children fail to achieve normal acuity or stereopsis even after extended periods of treatment. There are a number of promising experimental treatments that may improve compliance and outcomes, such as the playing of action video games with the strong eye patched. Although there may be a sensitive period for optimal effects of treatment, there is evidence that amblyopic adults may still show some benefit of treatment. However, there is as yet no consensus on the treatment of adults with amblyopia.
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Affiliation(s)
- Dennis M Levi
- School of Optometry & Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, United States.
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16
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Abstract
Recent work has transformed our ideas about the neural mechanisms, behavioral consequences and effective therapies for amblyopia. Since the 1700's, the clinical treatment for amblyopia has consisted of patching or penalizing the strong eye, to force the "lazy" amblyopic eye, to work. This treatment has generally been limited to infants and young children during a sensitive period of development. Over the last 20 years we have learned much about the nature and neural mechanisms underlying the loss of spatial and binocular vision in amblyopia, and that a degree of neural plasticity persists well beyond the sensitive period. Importantly, the last decade has seen a resurgence of research into new approaches to the treatment of amblyopia both in children and adults, which emphasize that monocular therapies may not be the most effective for the fundamentally binocular disorder that is amblyopia. These approaches include perceptual learning, video game play and binocular methods aimed at reducing inhibition of the amblyopic eye by the strong fellow eye, and enhancing binocular fusion and stereopsis. This review focuses on the what we've learned over the past 20 years or so, and will highlight both the successes of these new treatment approaches in labs around the world, and their failures in clinical trials. Reconciling these results raises important new questions that may help to focus future directions.
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Affiliation(s)
- Dennis M Levi
- University of California, Berkeley, School of Optometry & Helen Wills Neuroscience Institute, Berkeley, CA, USA.
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17
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Lu Z, Huang Y, Lu Q, Feng L, Nguchu BA, Wang Y, Wang H, Li G, Zhou Y, Qiu B, Zhou J, Wang X. Abnormal intra-network architecture in extra-striate cortices in amblyopia: a resting state fMRI study. EYE AND VISION 2019; 6:20. [PMID: 31334295 PMCID: PMC6615160 DOI: 10.1186/s40662-019-0145-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 06/13/2019] [Indexed: 11/18/2022]
Abstract
Background Amblyopia (lazy eye) is one of the most common causes of monocular visual impairment. Intensive investigation has shown that amblyopes suffer from a range of deficits not only in the primary visual cortex but also the extra-striate visual cortex. However, amblyopic brain processing deficits in large-scale information networks especially in the visual network remain unclear. Methods Through resting state functional magnetic resonance imaging (rs-fMRI), we studied the functional connectivity and efficiency of the brain visual processing networks in 18 anisometropic amblyopic patients and 18 healthy controls (HCs). Results We found a loss of functional correlation within the higher visual network (HVN) and the visuospatial network (VSN) in amblyopes. Additionally, compared with HCs, amblyopic patients exhibited disruptions in local efficiency in the V3v (third visual cortex, ventral part) and V4 (fourth visual cortex) of the HVN, as well as in the PFt, hIP3 (human intraparietal area 3), and BA7p (Brodmann area 7 posterior) of the VSN. No significant alterations were found in the primary visual network (PVN). Conclusion Our results indicate that amblyopia results in an intrinsic decrease of both network functional correlations and local efficiencies in the extra-striate visual networks.
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Affiliation(s)
- Zhuo Lu
- 1Center for Biomedical Engineering, University of Science and Technology of China, Hefei, Anhui 230027 People's Republic of China
| | - Yufeng Huang
- 2Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027 People's Republic of China.,3CAS Key Laboratory of Brain Function and Diseases and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027 People's Republic of China.,4Shenyang Aerospace University, Shenyang, Liaoning 110136 People's Republic of China
| | - Qilin Lu
- 2Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027 People's Republic of China.,3CAS Key Laboratory of Brain Function and Diseases and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027 People's Republic of China
| | - Lixia Feng
- 5Department of Ophthalmology, First Affiliated Hospital of Anhui Medical University, Hefei, Anhui People's Republic of China
| | - Benedictor Alexander Nguchu
- 1Center for Biomedical Engineering, University of Science and Technology of China, Hefei, Anhui 230027 People's Republic of China
| | - Yanming Wang
- 1Center for Biomedical Engineering, University of Science and Technology of China, Hefei, Anhui 230027 People's Republic of China
| | - Huijuan Wang
- 1Center for Biomedical Engineering, University of Science and Technology of China, Hefei, Anhui 230027 People's Republic of China
| | - Geng Li
- Asia Pediatric Ophthalmologist Association, Rm 2006, CC Wu Bldg., 302-308 Hennessy Rd., Wanchai, Hong Kong, People's Republic of China
| | - Yifeng Zhou
- 2Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027 People's Republic of China.,3CAS Key Laboratory of Brain Function and Diseases and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027 People's Republic of China
| | - Bensheng Qiu
- 1Center for Biomedical Engineering, University of Science and Technology of China, Hefei, Anhui 230027 People's Republic of China
| | - Jiawei Zhou
- 7School of Ophthalmology and Optometry and Eye hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325003 People's Republic of China
| | - Xiaoxiao Wang
- 1Center for Biomedical Engineering, University of Science and Technology of China, Hefei, Anhui 230027 People's Republic of China.,2Hefei National Laboratory for Physical Sciences at the Microscale and School of Life Science, University of Science and Technology of China, Hefei, Anhui 230027 People's Republic of China.,3CAS Key Laboratory of Brain Function and Diseases and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027 People's Republic of China
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18
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Visuomotor Behaviour in Amblyopia: Deficits and Compensatory Adaptations. Neural Plast 2019; 2019:6817839. [PMID: 31281344 PMCID: PMC6590572 DOI: 10.1155/2019/6817839] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 05/28/2019] [Indexed: 01/04/2023] Open
Abstract
Amblyopia is a neurodevelopmental visual disorder arising from decorrelated binocular experience during the critical periods of development. The hallmark of amblyopia is reduced visual acuity and impairment in binocular vision. The consequences of amblyopia on various sensory and perceptual functions have been studied extensively over the past 50 years. Historically, relatively fewer studies examined the impact of amblyopia on visuomotor behaviours; however, research in this area has flourished over the past 10 years. Therefore, the aim of this review paper is to provide a comprehensive review of current knowledge about the effects of amblyopia on eye movements, upper limb reaching and grasping movements, as well as balance and gait. Accumulating evidence indicates that amblyopia is associated with considerable deficits in visuomotor behaviour during amblyopic eye viewing, as well as adaptations in behaviour during binocular and fellow eye viewing in adults and children. Importantly, due to amblyopia heterogeneity, visuomotor development in children and motor skill performance in adults may be significantly influenced by the etiology and clinical features, such as visual acuity and stereoacuity. Studies with larger cohorts of children and adults are needed to disentangle the unique contribution of these clinical characteristics to the development and performance of visuomotor behaviours.
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Thompson B, Maehara G, Goddard E, Farivar R, Mansouri B, Hess RF. Long-Range Interocular Suppression in Adults with Strabismic Amblyopia: A Pilot fMRI Study. Vision (Basel) 2019; 3:vision3010002. [PMID: 31735803 PMCID: PMC6802762 DOI: 10.3390/vision3010002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 12/15/2018] [Accepted: 12/31/2018] [Indexed: 11/24/2022] Open
Abstract
Interocular suppression plays an important role in the visual deficits experienced by individuals with amblyopia. Most neurophysiological and functional MRI studies of suppression in amblyopia have used dichoptic stimuli that overlap within the visual field. However, suppression of the amblyopic eye also occurs when the dichoptic stimuli do not overlap, a phenomenon we refer to as long-range suppression. We used functional MRI to test the hypothesis that long-range suppression reduces neural activity in V1, V2 and V3 in adults with amblyopia, indicative of an early, active inhibition mechanism. Five adults with amblyopia and five controls viewed monocular and dichoptic quadrant stimuli during fMRI. Three of five participants with amblyopia experienced complete perceptual suppression of the quadrants presented to their amblyopic eye under dichoptic viewing. The blood oxygen level dependant (BOLD) responses within retinotopic regions corresponding to amblyopic and fellow eye stimuli were analyzed for response magnitude, time to peak, effective connectivity and stimulus classification. Dichoptic viewing slightly reduced the BOLD response magnitude in amblyopic eye retinotopic regions in V1 and reduced the time to peak response; however, the same effects were also present in the non-dominant eye of controls. Effective connectivity was unaffected by suppression, and the results of a classification analysis did not differ significantly between the control and amblyopia groups. Overall, we did not observe a neural signature of long-range amblyopic eye suppression in V1, V2 or V3 using functional MRI in this initial study. This type of suppression may involve higher level processing areas within the brain.
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Affiliation(s)
- Benjamin Thompson
- School of Optometry and Vision Science, University of Waterloo, Waterloo, ON N2L 3G1, Canada
- McGill Vision Research, Department of Ophthalmology and Visual Sciences, McGill University, Montreal, QC H4A 3S5, Canada
- School of Optometry and Vision Science, University of Auckland, Auckland 1142, New Zealand
- Correspondence: ; Tel.: +1-519-888-4567 (39398)
| | - Goro Maehara
- Department of Human Sciences, Kanagawa University, Yokohama 221-8686, Japan
| | - Erin Goddard
- McGill Vision Research, Department of Ophthalmology and Visual Sciences, McGill University, Montreal, QC H4A 3S5, Canada
| | - Reza Farivar
- McGill Vision Research, Department of Ophthalmology and Visual Sciences, McGill University, Montreal, QC H4A 3S5, Canada
| | - Behzad Mansouri
- Department of Ophthalmology, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Robert F. Hess
- McGill Vision Research, Department of Ophthalmology and Visual Sciences, McGill University, Montreal, QC H4A 3S5, Canada
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