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Sohns E, Szmulewicz DJ, Tarnutzer AA. Oculomotor and Vestibular Deficits in Friedreich Ataxia - Systematic Review and Meta-Analysis of Quantitative Measurements. CEREBELLUM (LONDON, ENGLAND) 2024:10.1007/s12311-024-01716-8. [PMID: 39066865 DOI: 10.1007/s12311-024-01716-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/25/2024] [Indexed: 07/30/2024]
Abstract
Disease-specific oculomotor assessments play a crucial role in the early diagnosis of hereditary cerebellar ataxias. Whereas several studies have reported on quantitative oculomotor and vestibular measurements in Friedreich's Ataxia (FRDA), the value of specific oculomotor paradigms remains unclear. We aimed to address this knowledge gap through a systematic literature review and providing disease-specific recommendations for a tailored set of eye-movement recordings in FRDA. MEDLINE and Embase were searched for studies reporting on quantitative oculomotor and/or vestibular measurements in FRDA-patients. Data on oculomotor and vestibular parameters were extracted and correlations with a range of clinical parameters were sought. Included studies (n = 17) reported on 185 patients. Abnormalities observed included the presence of saccadic intrusions (143/161) such as square-wave jerks (SWJ, 90/109) and ocular flutter (21/43), impaired eccentric gaze-holding (40/104), abnormal pursuit (81/93) and angular vestibulo-ocular reflex (aVOR) deficits (39/48). For visually-guided saccades (VGS), we frequently observed increases in saccade latency (27/38) and dysmetric saccades (71/93), whereas saccade velocity was more often preserved (37/43). Augmented anti-saccade (AS) latency, downbeat nystagmus and frequent macro-SWJ correlated with disease duration. Increased AS-latency and VGS-latency, frequent macro-SWJ, reduced aVOR-gain and augmented aVOR peak-latency correlated with disease severity. A broad range of oculomotor and vestibular deficits are documented in the literature. Impairments in pursuit, saccades and aVOR-responses are most commonly reported, and as such, should be prioritized as disease markers. Quantitative oculomotor testing in FRDA may facilitate early diagnosis and prove valuable in monitoring disease progression and treatment response.
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Affiliation(s)
- E Sohns
- Faculty of Medicine, University of Zurich, Zurich, Switzerland
| | - D J Szmulewicz
- Balance Disorders & Ataxia Service, Royal Victorian Eye and Ear Hospital, Melbourne, VIC, Australia
- The Bionics Institute, Melbourne, VIC, Australia
- University of Melbourne AU, Melbourne, VIC, Australia
| | - A A Tarnutzer
- Faculty of Medicine, University of Zurich, Zurich, Switzerland.
- Neurology, Cantonal Hospital of Baden, Im Ergel 1, Baden, 5404, Switzerland.
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Grossman SN, Rucker JC. Opsoclonus and ocular flutter: evaluation and management. Curr Opin Ophthalmol 2023; 34:465-469. [PMID: 37603546 DOI: 10.1097/icu.0000000000000998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/23/2023]
Abstract
PURPOSE OF REVIEW Opsoclonus and ocular flutter are saccadic intrusions characterized by spontaneous, back-to-back, fast eye movements (saccades) that oscillate about the midline of central visual fixation without intervening inter-saccadic intervals. When this type of movement occurs exclusively in the horizontal plane, it is called ocular flutter. When it occurs in multiple planes (i.e. horizontal, vertical, and torsional) it is called opsoclonus. The most common etiologic categories are parainfectious and paraneoplastic diseases. Less common are toxic-metabolic, traumatic, or idiopathic origins. The mechanism of these movements relates to dysfunction of brainstem and cerebellar machinery involved in the generation of saccades. In this review, we discuss the characteristics of opsoclonus and ocular flutter, describe approaches to clinical evaluation and management of the patient with opsoclonus and ocular flutter, and review approaches to therapeutic intervention. RECENT FINDINGS Recent publications demonstrated eye position-dependent opsoclonus present only in left gaze, which may be related to dysfunction of frontal eye fields or structures in the cerebellar vermis. SUMMARY Opsoclonus and ocular flutter originate from a broad array of neuropathologies and have value from both a neuroanatomic and etiologic perspective.
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Affiliation(s)
| | - Janet C Rucker
- Department of Neurology
- Department of Ophthalmology, New York University Grossman School of Medicine, New York, New York, USA
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Miraclin AT, Mani AM, Sivadasan A, Nair A, Christina M, Gojer AR, Milton S, Jude Prakash JA, Benjamin RN, Prabhakar AT, Mathew V, Aaron S. Opsoclonus myoclonus ataxia syndrome, ovarian teratoma and anti-NMDAR antibody: an 'unresolved' mystery. BMJ Neurol Open 2023; 5:e000414. [PMID: 37396795 PMCID: PMC10314564 DOI: 10.1136/bmjno-2023-000414] [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] [Accepted: 05/20/2023] [Indexed: 07/04/2023] Open
Abstract
Background Opsoclonus-myoclonus-ataxia syndrome (OMAS) is characterised by the combination of opsoclonus and arrhythmic action myoclonus with axial ataxia and dysarthria. In adults, a majority are paraneoplastic secondary to solid organ tumours and could harbour antibodies against intracellular epitopes; however, certain proportions have detectable antibodies to various neuronal cell surface antigens. Anti-N-methyl-D-aspartate (NMDAR) antibodies and ovarian teratomas have been implicated in OMAS. Methods Report of two cases and review of literature. Results Two middle-aged women presented with subacute-onset, rapidly progressive OMAS and behavioural changes consistent with psychosis. The first patient had detectable antibodies to NMDAR in the cerebrospinal fluid (CSF) alone. Evaluation for ovarian teratoma was negative. The second patient had no detectable antibodies in serum or CSF; however, she had an underlying ovarian teratoma. Patient A was treated with pulse steroids, therapeutic plasma exchange (TPE) followed by bortezomib (BOR) and dexamethasone, while patient B was treated with steroids, TPE followed by surgical resection of ovarian teratoma. Both patients had favourable outcomes and were asymptomatic at the 6 monthly follow-up. Conclusions With coexistent neuropsychiatric manifestations, OMAS can be considered a distinct entity of autoimmune encephalitis, pathogenesis being immune activation against known/unknown neuronal cell surface antigens. The observation of absence of anti-NMDAR antibody in patients with teratoma-associated OMAS and vice versa is intriguing. Further research on the potential role of ovarian teratoma in evoking neuronal autoimmunity and its targets is required. The management challenge in both cases including the potential use of BOR has been highlighted.
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Affiliation(s)
- Angel T Miraclin
- Department of Neurosciences, Christian Medical College Vellore, Vellore, Tamil Nadu, India
| | - Arun Mathai Mani
- Department of Neurosciences, Christian Medical College Vellore, Vellore, Tamil Nadu, India
| | - Ajith Sivadasan
- Department of Neurosciences, Christian Medical College Vellore, Vellore, Tamil Nadu, India
| | - Aditya Nair
- Department of Neurosciences, Christian Medical College Vellore, Vellore, Tamil Nadu, India
| | - Munagapati Christina
- Department of Psychiatry, Christian Medical College Vellore, Vellore, Tamil Nadu, India
| | - Abigail Ruth Gojer
- Department of Psychiatry, Christian Medical College Vellore, Vellore, Tamil Nadu, India
| | - Sharon Milton
- Department of Clinical Pathology, Christian Medical College Vellore, Vellore, Tamil Nadu, India
| | - John A Jude Prakash
- Department of Clinical Microbiology, Christian Medical College Vellore, Vellore, Tamil Nadu, India
| | - Rohit N Benjamin
- Department of Neurosciences, Christian Medical College Vellore, Vellore, Tamil Nadu, India
| | | | - Vivek Mathew
- Department of Neurosciences, Christian Medical College Vellore, Vellore, Tamil Nadu, India
| | - Sanjith Aaron
- Department of Neurosciences, Christian Medical College Vellore, Vellore, Tamil Nadu, India
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Nelson JL, Blume GM, Bansal SK, Kaufman JR, Woods FR, Zhang X, Kattah JC. Postinfectious SARS-CoV-2 Opsoclonus-Myoclonus-Ataxia Syndrome. J Neuroophthalmol 2022; 42:251-255. [PMID: 34974489 DOI: 10.1097/wno.0000000000001498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND The opsoclonus-myoclonus-ataxia syndrome (OMAS) represents a pathophysiology and diagnostic challenge. Although the diverse etiologies likely share a common mechanism to generate ocular, trunk, and limb movements, the underlying cause may be a paraneoplastic syndrome, as the first sign of cancer, or may be a postinfectious complication, and thus, the outcome depends on identifying the trigger mechanism. A recent hypothesis suggests increased GABAA receptor sensitivity in the olivary-oculomotor vermis-fastigial nucleus-premotor saccade burst neuron circuit in the brainstem. Therefore, OMAS management will focus on immunosuppression and modulation of GABAA hypersensitivity with benzodiazepines. METHODS We serially video recorded the eye movements at the bedside of 1 patient with SARS-CoV-2-specific Immunoglobulin G (IgG) serum antibodies, but twice-negative nasopharyngeal reverse transcription polymerase chain reaction (RT-PCR). We tested cerebrospinal fluid (CSF), serum, and nasopharyngeal samples. After brain MRI and chest, abdomen, and pelvis CT scans, we treated our patient with clonazepam and high-dose Solu-MEDROL, followed by a rituximab infusion after her formal eye movement analysis 10 days later. RESULTS The recordings throughout her acute illness demonstrated different eye movement abnormalities. While on high-dose steroids and clonazepam, she initially had macrosaccadic oscillations, followed by brief ocular flutter during convergence the next day; after 10 days, she had bursts of opsoclonus during scotopic conditions with fixation block but otherwise normal eye movements. Concern for a suboptimal response to high-dose Solu-MEDROL motivated an infusion of rituximab, which induced remission. An investigation for a paraneoplastic etiology was negative. CSF testing showed elevated neuron-specific enolase. Serum IgG to Serum SARS-CoV2 IgG was elevated with negative RT-PCR nasopharyngeal testing. CONCLUSION A recent simulation model of macrosaccadic oscillations and OMAS proposes a combined pathology of brainstem and cerebellar because of increased GABAA receptor sensitivity. In this case report, we report 1 patient with elevated CSF neuronal specific enolase, macrosaccadic oscillations, ocular flutter, and OMAS as a SARS-CoV-2 postinfectious complication. Opsoclonus emerged predominantly with fixation block and suppressed with fixation, providing support to modern theories on the mechanism responsible for these ocular oscillations involving cerebellar-brainstem pathogenesis.
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Affiliation(s)
- Jodi L Nelson
- Department of Neurology (JN, GB, FW, XZ, and JK), University of Illinois College of Medicine Peoria, Illinois Neurologic Institute, OSF St. Francis Medical Center, Peoria, Illinois; Department of Neurology (JK and FW), Illinois Neurologic Institute OSF St. Francis Medical Center, Peoria, Illinois; and Department of Internal Medicine (SB), University of Illinois College of Medicine Peoria, OSF St. Francis Medical Center, Peoria, Illinois
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Kirchner J, Watson TL, Busch NA, Lappe M. Timing and kinematics of horizontal within-blink saccades measured using EOG. J Neurophysiol 2022; 127:1655-1668. [PMID: 35647737 DOI: 10.1152/jn.00076.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Eye blinks are the brief closures of the lid. They are accompanied by a co-contraction of the eye muscles that temporarily pulls the whole eyeball back into its socket. When blinks occur together with execution of saccadic gaze shifts, they interfere with the saccadic premotor circuit, causing these within-blink saccades to be slower than normal and also time-locked to blinks. In order to analyse the trajectory of within-blink saccades, the subtraction of the entangled blink-related eye movement is required. Here we propose a combination of principal component analysis (PCA) and a regression model to subtract the blink-related component of the eye movement based on the respective blink metrics. We used electrooculography (EOG) to measure eye and lid movements of twelve participants who performed saccades with and without blinks. We found that within-blink saccades are slower than without-blink saccades and are tightly coupled in time to blink onset. Surprisingly, in some participants we observed large dynamic overshoots of up to 15° for saccades of only 5° amplitude. This finding challenges the current view that within-blink saccades are programmed as slow, but straight, saccades. We hypothesise that the dynamic overshoots could either be attributed to inhibition of omnipause neurons during blinks, the simultaneous co-contraction of extraocular muscles or a combination of both.
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Affiliation(s)
- Johannes Kirchner
- Institute for Psychology, grid.5949.1University of Münster, Münster, Germany
| | - Tamara Lea Watson
- School of Psychology, The University of Western Sydney, Sydney, Australia
| | - Niko A Busch
- Westfälische Wilhelms-Universität Münster, Münster, Nordrhein-Westfalen, Germany
| | - Markus Lappe
- Otto-Creutzfeldt Center for Cognitive and Behavioural Neuroscience, University of Muenster
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Merati M, Rucker JC, McKeon A, Frucht SJ, Hu J, Balcer LJ, Galetta SL. A Case of Opsoclonus-Myoclonus-Ataxia With Neuronal Intermediate Filament IgG Detected in Cerebrospinal Fluid. J Neuroophthalmol 2022; 42:278-281. [PMID: 35594157 PMCID: PMC9620397 DOI: 10.1097/wno.0000000000001599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
ABSTRACT A 62-year-old man presented with headache, fever, and malaise. He was diagnosed with Anaplasma phagocytophilum, confirmed by serum polymerase chain reaction, and started on oral doxycycline. After 5 days of treatment, the patient began to experience gait imbalance with frequent falls, as well as myoclonus, and confusion. Examination was notable for opsoclonus-myoclonus-ataxia (OMA) and hypometric saccades. Cerebrospinal fluid (CSF) autoimmune encephalitis panel demonstrated a markedly elevated neuronal intermediate filament (NIF) immunoglobulin G antibody titer of 1:16, with positive neurofilament light- and heavy-chain antibodies. These antibodies were suspected to have been triggered by the Anaplasma infection. Repeat CSF examination 8 days later still showed a positive immunofluorescence assay for NIF antibodies, but the CSF titer was now less than 1:2. Body computed tomography imaging was unrevealing for an underlying cancer. Our patient illustrates a postinfectious mechanism for OMA and saccadic hypometria after Anaplasma infection.
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Affiliation(s)
- Melody Merati
- Department of Neurology (MM, JCR, SJF, LJB, SLG), New York University Grossman School of Medicine, New York, New York; Department of Neurology (AM, MDM), Mayo Clinic, Rochester, MN; and Departments of Radiology (JH), Ophthalmology (JCR, LJB, SLG), and Department of Population Health (LJB), New York University Grossman School of Medicine, New York, New York
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7
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Kassavetis P, Kaski D, Anderson T, Hallett M. Eye Movement Disorders in Movement Disorders. Mov Disord Clin Pract 2022; 9:284-295. [PMID: 35402641 PMCID: PMC8974874 DOI: 10.1002/mdc3.13413] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 11/24/2021] [Accepted: 12/03/2021] [Indexed: 11/05/2022] Open
Abstract
Oculomotor assessment is an essential element of the neurological clinical examination and is particularly important when evaluating patients with movements disorders. Most of the brain is involved in oculomotor control, and thus many neurological conditions present with oculomotor abnormalities. Each of the different classes of eye movements and their features can provide important information that can facilitate differential diagnosis. This educational review presents a clinical approach to eye movement abnormalities that are commonly seen in parkinsonism, ataxia, dystonia, myoclonus, tremor, and chorea. In parkinsonism, subtle signs such as prominent square wave jerks, impaired vertical optokinetic nystagmus, and/or the "round the houses" sign suggest early progressive supranuclear gaze palsy before vertical gaze is restricted. In ataxia, nystagmus is common, but other findings such as oculomotor apraxia, supranuclear gaze palsy, impaired fixation, or saccadic pursuit can contribute to diagnoses such as ataxia with oculomotor apraxia, Niemann-Pick type C, or ataxia telangiectasia. Opsoclonus myoclonus and oculopalatal myoclonus present with characteristic phenomenology and are usually easy to identify. The oculomotor exam is usually unremarkable in isolated dystonia, but oculogyric crisis is a medical emergency and should be recognized and treated in a timely manner. Gaze impersistence in a patient with chorea suggests Huntington's disease, but in a patient with dystonia or tremor, Wilson's disease is more likely. Finally, functional eye movements can reinforce the clinical impression of a functional movement disorder.
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Affiliation(s)
- Panagiotis Kassavetis
- National Institute of Neurological Disorders and Stroke, National Institutes of HealthBethesdaMarylandUSA
- Department of NeurologyUniversity of UtahSalt Lake CityUtahUSA
| | - Diego Kaski
- Centre for Vestibular and Behavioural Neurosciences, Department of Clinical and Movement NeurosciencesUniversity College London, Institute of NeurologyLondonUK
| | - Tim Anderson
- New Zealand Brain Research InstituteChristchurchNew Zealand
- Department of MedicineUniversity of OtagoChristchurchNew Zealand
| | - Mark Hallett
- National Institute of Neurological Disorders and Stroke, National Institutes of HealthBethesdaMarylandUSA
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8
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Robinson DA. Neurophysiology, pathology and models of rapid eye movements. PROGRESS IN BRAIN RESEARCH 2022; 267:287-317. [PMID: 35074059 DOI: 10.1016/bs.pbr.2021.10.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
This chapter discusses the premotor neural mechanisms that control horizontal saccadic eye movements. Oculomotoneurons carry a pulse-step signal that underlies the pulse-step force driving the overdamped plant. The pulse and step are both generated by a common signal, arising from medium-lead burst neurons in the pons. Their burst signal encodes saccadic eye velocity, while the number of spikes in the burst relates to the saccade amplitude. The step component, which encodes the eye position, is obtained by neural integration of the burst. Several oculomotor neural disorders can be explained by impairments in the binocular push-pull organization of this pulse-step mechanism. Plasticity of the pulse-step control, e.g., in response to muscle weakening, is mediated by cerebellar vermis and flocculus. Saccadic offset may be controlled, either by active braking, or by an exponential slide signal. The neurophysiology is summarized by a quantitative model, in which the firing rate of burst neurons is controlled by a dynamic negative feedback loop that carries the instantaneous eye position signal from the neural integrator. This signal is compared with a desired eye-position command in the head from higher centers, and the resulting dynamic motor error drives the high-gain burst cells. Instability of the system is prevented by the mutual inhibitory interaction between burst cells and omnipause neurons. The model explains many features of normal saccades, but also accounts for pathologies and abnormalities like dynamic overshoots and saccade oscillations.
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Affiliation(s)
- David A Robinson
- Late Professor of Ophthalmology, Biomedical Engineering and Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, United States
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9
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Neuro-Ophthalmological Findings in Friedreich's Ataxia. J Pers Med 2021; 11:jpm11080708. [PMID: 34442352 PMCID: PMC8398238 DOI: 10.3390/jpm11080708] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 07/08/2021] [Accepted: 07/21/2021] [Indexed: 12/17/2022] Open
Abstract
Friedreich ataxia (FRDA) is a progressive neurodegenerative disease caused by a severe autosomal recessive genetic disorder of the central nervous (CNS) and peripheral nervous system (PNS), affecting children and young adults. Its onset is before 25 years of age, with mean ages of onset and death between 11 and 38 years, respectively. The incidence is 1 in 30,000–50,000 persons. It is caused, in 97% of cases, by a homozygous guanine-adenine-adenine (GAA) trinucleotide mutation in the first intron of the frataxin (FXN) gene on chromosome 9 (9q13–q1.1). The mutation of this gene causes a deficiency of frataxin, which induces an altered inflow of iron into the mitochondria, increasing the nervous system’s vulnerability to oxidative stress. The main clinical signs include spinocerebellar ataxia with sensory loss and disappearance of deep tendon reflexes, cerebellar dysarthria, cardiomyopathy, and scoliosis. Diabetes, hearing loss, and pes cavus may also occur, and although most patients with FRDA do not present with symptomatic visual impairment, 73% present with clinical neuro-ophthalmological alterations such as optic atrophy and altered eye movement, among others. This review provides a brief overview of the main aspects of FRDA and then focuses on the ocular involvement of this pathology and the possible use of retinal biomarkers.
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Li M, Wu J, Ma W, Zhang Z, Zhang M, Li X, Ling Z, Xu X. Spatiotemporal characteristics of postsaccadic dynamic overshoot in young and elderly subjects. iScience 2021; 24:102764. [PMID: 34308287 PMCID: PMC8283153 DOI: 10.1016/j.isci.2021.102764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 03/14/2021] [Accepted: 06/21/2021] [Indexed: 11/10/2022] Open
Abstract
Saccadic eye movements may not stop steadily but fluctuate briefly, known as saccadic dynamic overshoot (SDO). The reported relationships between SDO and saccadic parameters of main saccade and the effect of aging on SDO are controversial. In addition, it is not clear whether aging-related disease, such as mild cognitive impairment (MCI) and Parkinson disease (PD), causes the specific change of SDO. To address these questions, we analyzed the spatiotemporal features of SDO in young healthy subjects, elderly healthy subjects, and subjects with PD and MCI in three oculomotor tasks. We found two types of SDOs—simple and complex SDO. We confirmed that the frequency and amplitude of SDO were positively correlated with the peak velocity and deceleration of main saccades and increased in elderly subjects; however, they were not significantly different among the three elderly groups. Our results support the previous argument that the oculomotor structure in brainstem and cerebellum directly develop SDO. We classify two types of saccadic dynamic overshoot (SDO): SDOsimple and SDOcomplex Saccades with SDO have higher peak velocity and deceleration than saccades without SDO Elderly subjects show a higher frequency and amplitude of SDO than young subjects Saccades with SDOcomplex occur more frequently in reflexive than voluntary saccades
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Affiliation(s)
- Min Li
- State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Division of Psychology, Beijing Normal University, Beijing 100875, China
| | - Junru Wu
- State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Division of Psychology, Beijing Normal University, Beijing 100875, China
| | - Wenbo Ma
- State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Division of Psychology, Beijing Normal University, Beijing 100875, China
| | - Zhihao Zhang
- State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Division of Psychology, Beijing Normal University, Beijing 100875, China
| | - Mingsha Zhang
- State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Division of Psychology, Beijing Normal University, Beijing 100875, China
| | - Xuemei Li
- Cadre Medical Department, the 1st Clinical Center, General Hospital of PLA, 28 Fu-Xing Road, Haidian District, Beijing 100853, China
| | - Zhipei Ling
- Department of Neurosurgery, General Hospital of PLA, 28 Fu-Xing Road, Haidian District, Beijing 100853, China
| | - Xin Xu
- Department of Neurosurgery, General Hospital of PLA, 28 Fu-Xing Road, Haidian District, Beijing 100853, China
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11
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Southgate DC, Barras N, Kummer L. The effect of three different visual monitoring strategies on the accuracy of leg‐before‐wicket decisions by cricket umpires. Clin Exp Optom 2021; 91:385-93. [DOI: 10.1111/j.1444-0938.2007.00223.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
| | - Neil Barras
- School of Medical Sciences, Royal Melbourne Institute of Technology, Bundoora, Australia E‐mail:
| | - Lyndall Kummer
- School of Medical Sciences, Royal Melbourne Institute of Technology, Bundoora, Australia E‐mail:
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12
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Rucker JC, Rizzo JR, Hudson TE, Horn AKE, Buettner-Ennever JA, Leigh RJ, Optican LM. Dysfunctional mode switching between fixation and saccades: collaborative insights into two unusual clinical disorders. J Comput Neurosci 2021; 49:283-293. [PMID: 33839988 DOI: 10.1007/s10827-021-00785-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 02/01/2021] [Accepted: 02/24/2021] [Indexed: 11/28/2022]
Abstract
Voluntary rapid eye movements (saccades) redirect the fovea toward objects of visual interest. The saccadic system can be considered as a dual-mode system: in one mode the eye is fixating, in the other it is making a saccade. In this review, we consider two examples of dysfunctional saccades, interrupted saccades in late-onset Tay-Sachs disease and gaze-position dependent opsoclonus after concussion, which fail to properly shift between fixation and saccade modes. Insights and benefits gained from bi-directional collaborative exchange between clinical and basic scientists are emphasized. In the case of interrupted saccades, existing mathematical models were sufficiently detailed to provide support for the cause of interrupted saccades. In the case of gaze-position dependent opsoclonus, existing models could not explain the behavior, but further development provided a reasonable hypothesis for the mechanism underlying the behavior. Collaboration between clinical and basic science is a rich source of progress for developing biologically plausible models and understanding neurological disease. Approaching a clinical problem with a specific hypothesis (model) in mind often prompts new experimental tests and provides insights into basic mechanisms.
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Affiliation(s)
- Janet C Rucker
- Departments of Neurology, New York University Grossman School of Medicine, New York, NY, USA. .,Departments of Ophthalmology, New York University Grossman School of Medicine, New York, NY, USA.
| | - John-Ross Rizzo
- Departments of Neurology, New York University Grossman School of Medicine, New York, NY, USA.,Departments of Rehabilitation Medicine, New York University Grossman School of Medicine, New York, NY, USA.,Departments of Biomedical Engineering, New York University Tandon School of Engineering, New York, NY, USA.,Departments of Mechanical and Aerospace Engineering, New York University Tandon School of Engineering, New York, NY, USA
| | - Todd E Hudson
- Departments of Neurology, New York University Grossman School of Medicine, New York, NY, USA.,Departments of Rehabilitation Medicine, New York University Grossman School of Medicine, New York, NY, USA
| | - Anja K E Horn
- Department of Anatomy and Cell Biology I, Ludwig-Maximilians University, Munich, Germany
| | | | - R John Leigh
- Department of Neurology, Case Western Reserve University, Cleveland, OH, USA
| | - Lance M Optican
- Laboratory of Sensorimotor Research, NEI, NIH, DHHS, Bethesda, MD, USA
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Saini L, Dhawan SR, Madaan P, Suthar R, Saini AG, Sahu JK, Sankhyan N. Infection-Associated Opsoclonus: A Retrospective Case Record Analysis and Review of Literature. J Child Neurol 2020; 35:480-484. [PMID: 32216501 DOI: 10.1177/0883073820911327] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Opsoclonus, an uncommon clinical sign, and is often described in the context of opsoclonus myoclonus ataxia syndrome (OMAS). OMAS may be paraneoplastic or postinfectious. However, opsoclonus with or without OMAS may occur in association with a wide gamut of infections. Infection-associated opsoclonus/OMAS (IAO) needs recognition as a separate entity, since it demands relatively brief immunosuppression, symptomatic treatment, and has a better outcome. Case records of children, who presented with opsoclonus to a tertiary-care teaching hospital of North India over a period of 1 year (2017-2018), were reviewed. Those with opsoclonus in the setting of an acute infection/febrile illness (symptomatic opsoclonus; IAO) were included. Of 15 children with opsoclonus, 6 children [median age: 42 months (range: 8 months to 7 years); 2 boys] had opsoclonus associated with an infective or febrile illness. Additional clinical findings in these children included myoclonus (n = 2), ataxia (n = 4) and behavioral abnormalities (n = 4). All these patients had an associated neurologic or nonneurologic illness- scrub typhus (n = 1), tuberculous meningitis (n = 1), mumps encephalitis (n = 1), brainstem encephalitis (n = 1), acute cerebellitis (n = 1), and subacute sclerosing panencephalitis (SSPE, n = 1). Children with acute cerebellitis, brainstem encephalitis, and mumps encephalitis were treated with steroids while those with scrub typhus, tuberculosis, and SSPE were treated with antibiotics, antitubercular therapy, and Isoprinosine, respectively. None of them needed long-term maintenance immunotherapy. The evaluation for tumor was negative in all. Three of the 6 children are functionally normal at the last follow-up. Acute neuro infections may trigger opsoclonus. A careful analysis of clinical data and suitable investigations can help differentiate these children from those with OMAS. This distinction may avoid unwarranted long-term immunosuppression.
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Affiliation(s)
- Lokesh Saini
- Pediatric Neurology Unit, Department of Pediatrics, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
| | - Sumeet R Dhawan
- Pediatric Neurology Unit, Department of Pediatrics, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
| | - Priyanka Madaan
- Pediatric Neurology Unit, Department of Pediatrics, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India.,Council of Scientific and Industrial Research, New Delhi
| | - Renu Suthar
- Pediatric Neurology Unit, Department of Pediatrics, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
| | - Arushi Gahlot Saini
- Pediatric Neurology Unit, Department of Pediatrics, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
| | - Jitendra Kumar Sahu
- Pediatric Neurology Unit, Department of Pediatrics, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
| | - Naveen Sankhyan
- Pediatric Neurology Unit, Department of Pediatrics, Post Graduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
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14
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Lee JY, Kwon E, Kim HJ, Choi JY, Oh HJ, Kim JS. Opsoclonus Following Downbeat Nystagmus in Absence of Visual Fixation in Multiple System Atrophy: Modulation and Mechanisms. THE CEREBELLUM 2019; 20:724-733. [PMID: 31838647 DOI: 10.1007/s12311-019-01090-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report atypical opsoclonus in a patient with multiple system atrophy and propose a mechanism based on the patterns of modulation by visual, vestibular, and saccadic and vergence stimulation. Firstly, the 6-Hz opsoclonus mostly in the vertical plane occurred only after the development of downbeat nystagmus in darkness without visual fixation. Even after a substantial build-up, visual suppression of the opsoclonus was immediate and complete. Furthermore, the latency for re-emergence of opsoclonus in darkness was greater when the duration of preceding visual fixation was longer. Secondly, the effect of preceding downbeat nystagmus on the development of opsoclonus was evaluated by changing the head position. The opsoclonus did not occur in the supine position when the downbeat nystagmus was absent. After horizontal head shaking, the opsoclonus in the vertical plane gradually evolved into horizontal plane and resumed its vertical direction again after vertical head shaking. Thirdly, any opsoclonus was not triggered by imaginary saccades in the supine position. Lastly, combined vergence and saccadic eye movements during the Müller paradigm did not induce opsoclonus. From these findings of modulation, we suggest that the opsoclonus observed in our patient was invoked by vestibular signals. When the function of the omnipause neurons and saccadic system was impaired, the centrally mediated vestibular eye velocity signals may activate the saccadic system to generate opsoclonus. These atypical patterns of opsoclonus, distinct from the classic opsoclonus frequently observed in para-neoplastic or para-infectious disorders, may be an unrevealing sign of degenerative brainstem or cerebellar disorders.
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Affiliation(s)
- Ju-Young Lee
- Dizziness Center and Clinical Neuroscience Center, Seoul National University Bundang Hospital, Seongnam, South Korea.,Department of Neurology, Seoul National University Bundang Hospital, 173-82 Gumi-ro, Bundang-gu, Seongnam, 13620, South Korea
| | - Eunjin Kwon
- Dizziness Center and Clinical Neuroscience Center, Seoul National University Bundang Hospital, Seongnam, South Korea.,Department of Neurology, Seoul National University Bundang Hospital, 173-82 Gumi-ro, Bundang-gu, Seongnam, 13620, South Korea
| | - Hyo-Jung Kim
- Research Administration Team, Seoul National Univertisy Bundang Hospital, Seongnam, South Korea
| | - Jeong-Yoon Choi
- Dizziness Center and Clinical Neuroscience Center, Seoul National University Bundang Hospital, Seongnam, South Korea. .,Department of Neurology, Seoul National University Bundang Hospital, 173-82 Gumi-ro, Bundang-gu, Seongnam, 13620, South Korea. .,Department of Neurology, College of Medicine, Seoul National University, Seoul, South Korea.
| | - Hui Jong Oh
- The MTV (Migraine, Tinnitus, and Vertigo) Clinic, Oh Neurology Center, Daegu, South Korea
| | - Ji-Soo Kim
- Dizziness Center and Clinical Neuroscience Center, Seoul National University Bundang Hospital, Seongnam, South Korea. .,Department of Neurology, Seoul National University Bundang Hospital, 173-82 Gumi-ro, Bundang-gu, Seongnam, 13620, South Korea. .,Department of Neurology, College of Medicine, Seoul National University, Seoul, South Korea.
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15
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Kaur A, Bhagwat C, Madaan P, Saini L, Bhatia A, Singh H, Sankhyan N. Dancing Eyes. J Pediatr 2019; 214:231. [PMID: 31303334 DOI: 10.1016/j.jpeds.2019.06.035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 06/09/2019] [Accepted: 06/11/2019] [Indexed: 10/26/2022]
Affiliation(s)
| | | | | | - Lokesh Saini
- Pediatric Neurology Unit, Department of Pediatrics
| | | | | | - Naveen Sankhyan
- Pediatric Neurology Unit, Department of Pediatrics, Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh, India
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16
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Shaikh AG, Zee DS. Eye Movement Research in the Twenty-First Century-a Window to the Brain, Mind, and More. THE CEREBELLUM 2019; 17:252-258. [PMID: 29260439 DOI: 10.1007/s12311-017-0910-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The study of eye movements not only addresses debilitating neuro-ophthalmological problems but has become an essential tool of basic neuroscience research. Eye movements are a classic way to evaluate brain function-traditionally in disorders affecting the brainstem and cerebellum. Abnormalities of eye movements have localizing value and help narrow the differential diagnosis of complex neurological problems. More recently, using sophisticated behavioral paradigms, measurement of eye movements has also been applied to disorders of the thalamus, basal ganglia, and cerebral cortex. Moreover, in contemporary neuroscience, eye movements play a key role in understanding cognition, behavior, and disorders of the mind. Examples include applications to higher-level decision-making processes as in neuroeconomics and psychiatric and cognitive disorders such as schizophrenia and autism. Eye movements have become valued as objective biomarkers to monitor the natural progression of disease and the effects of therapies. As specific genetic defects are identified for many neurological disorders, ocular motor function often becomes the cornerstone of phenotypic classification and differential diagnosis. Here, we introduce other important applications of eye movement research, including understanding movement disorders affecting the head and limbs. We also emphasize the need to develop standardized test batteries for eye movements of all types including the vestibulo-ocular responses. The evaluation and treatment of patients with cerebellar ataxia are particularly amenable to such an approach.
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Affiliation(s)
- Aasef G Shaikh
- Neurological Institute, University Hospitals Health System, Cleveland, OH, USA. .,Neurology Service, Louis Stokes Cleveland VA Medical Center, Cleveland, OH, USA. .,Department of Neurology, Case Western Reserve University, 11100 Euclid Avenue, Cleveland, OH, 44110, USA.
| | - David S Zee
- Department of Neuroscience, The Johns Hopkins University, Baltimore, MD, USA.,Department of Neurology, The Johns Hopkins University, Baltimore, MD, USA.,Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University, Baltimore, MD, USA.,Department of Ophthalmology, The Johns Hopkins University, Baltimore, MD, USA
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17
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Phokaewvarangkul O, Bhidayasiri R. How to spot ocular abnormalities in progressive supranuclear palsy? A practical review. Transl Neurodegener 2019; 8:20. [PMID: 31333840 PMCID: PMC6617936 DOI: 10.1186/s40035-019-0160-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 06/25/2019] [Indexed: 12/11/2022] Open
Abstract
Background For parkinsonian disorders, progressive supranuclear palsy (PSP) continues to be significant for differential diagnosis. PSP presents a range of ocular abnormalities that have been suggested as optional tools for its early detection, apart from the principal characteristic of postural unsteadiness. Nonetheless, such symptoms may be difficult to identify, particularly during the early onset stage of the disorder. It may also be problematic to recognize these symptoms for general practitioners who lack the required experience or physicians who are not specifically educated and proficient in ophthalmology or neurology. Main body Thus, here, a methodical evaluation was carried out to identify seven oculomotor abnormalities occurring in PSP, comprising square wave jerks, the speed and range of saccades (slow saccades and vertical supranuclear gaze palsy), ‘round the houses’ sign, decreased blink rate, blepharospasm, and apraxia of eyelid opening. Inspections were conducted using direct visual observation. An approach to distinguish these signs during a bedside examination was also established. When presenting in a patient with parkinsonism or dementia, the existence of such ocular abnormalities could increase the risk of PSP. For the distinction between PSP and other parkinsonian disorders, these signs hold significant value for physicians. Conclusion The authors urge all concerned physicians to check for such abnormalities with the naked eye in patients with parkinsonism. This method has advantages, including ease of application, reduced time-consumption, and requirement of minimal resources. It will also help physicians to conduct efficient diagnoses since many patients with PSP could intially present with ocular symptoms in busy outpatient clinics. Electronic supplementary material The online version of this article (10.1186/s40035-019-0160-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Onanong Phokaewvarangkul
- Chulalongkorn Center of Excellence for Parkinson Disease & Related Disorders, Department of Medicine, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand
| | - Roongroj Bhidayasiri
- Chulalongkorn Center of Excellence for Parkinson Disease & Related Disorders, Department of Medicine, Faculty of Medicine, Chulalongkorn University and King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand
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18
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Paraneoplastic Opsoclonus Myoclonus in a Patient with Pancreatic Adenocarcinoma. Case Rep Neurol Med 2019; 2019:3601026. [PMID: 31139479 PMCID: PMC6500640 DOI: 10.1155/2019/3601026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 03/15/2019] [Accepted: 03/27/2019] [Indexed: 11/17/2022] Open
Abstract
Opsoclonus myoclonus syndrome (OMS) is an extremely rare neurological syndrome typically affecting as few as 1 in 10,000,000 people annually. OMS is characterized by the presence of involuntary, saccadic eye movements, as well as ataxia, including gait incoordination, rigidity, and tremor. The origin of OMS is unclear, but a significant percentage of OMS cases are indicative of an underlying malignancy, most commonly neuroblastoma and small cell lung cancer. Here we describe an adult patient with OMS, who was ultimately diagnosed with a small ductal adenocarcinoma of the pancreas. To our knowledge, this is the third published report of an association between OMS and pancreatic malignancy, and the only case where the pancreatic malignancy was detected prior to metastasis or autopsy at death. This case report highlights the importance of careful, aggressive malignancy screening with OMS, as the pancreatic duct cut-off sign may be overlooked if pancreatic malignancy is not suspected.
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19
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Rizzo JR, Hudson TE, Sequeira AJ, Dai W, Chaudhry Y, Martone J, Zee DS, Optican LM, Balcer LJ, Galetta SL, Rucker JC. Eye position-dependent opsoclonus in mild traumatic brain injury. PROGRESS IN BRAIN RESEARCH 2019; 249:65-78. [PMID: 31325998 DOI: 10.1016/bs.pbr.2019.04.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/15/2023]
Abstract
Opsoclonus consists of bursts of involuntary, multidirectional, back-to-back saccades without an intersaccadic interval. We report a 60-year-old man with post-concussive headaches and disequilibrium who had small amplitude opsoclonus in left gaze, along with larger amplitude flutter during convergence. Examination was otherwise normal and brain MRI was unremarkable. Video-oculography demonstrated opsoclonus predominantly in left gaze and during pursuit in the left hemifield, which improved as post-concussive symptoms improved. Existing theories of opsoclonus mechanisms do not account for this eye position-dependence. We discuss theoretical mechanisms of this behavior, including possible dysfunction of frontal eye field and/or cerebellar vermis neurons; review ocular oscillations in traumatic brain injury; and consider the potential relationship between the larger amplitude flutter upon convergence and post-traumatic ocular oscillations.
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Affiliation(s)
- John-Ross Rizzo
- Department of Physical Medicine and Rehabilitation, New York University School of Medicine, New York, NY, United States; Department of Neurology, New York University School of Medicine, New York, NY, United States
| | - Todd E Hudson
- Department of Physical Medicine and Rehabilitation, New York University School of Medicine, New York, NY, United States; Department of Neurology, New York University School of Medicine, New York, NY, United States
| | - Alexandra J Sequeira
- Department of Neurology, New York University School of Medicine, New York, NY, United States
| | - Weiwei Dai
- Department of Neurology, New York University School of Medicine, New York, NY, United States; Department of Electrical and Computer Engineering, New York University Tandon School of Engineering, New York, NY, United States
| | - Yash Chaudhry
- Department of Neurology, New York University School of Medicine, New York, NY, United States
| | - John Martone
- Department of Neurology, New York University School of Medicine, New York, NY, United States
| | - David S Zee
- Department of Neurology, The Johns Hopkins University, Baltimore, MD, United States
| | - Lance M Optican
- Laboratory of Sensorimotor Research, NEI, NIH, DHHS, Bethesda, MD, United States
| | - Laura J Balcer
- Department of Neurology, New York University School of Medicine, New York, NY, United States; Department of Ophthalmology, New York University School of Medicine, New York, NY, United States; Department of Population Health, New York University School of Medicine, New York, NY, United States
| | - Steven L Galetta
- Department of Neurology, New York University School of Medicine, New York, NY, United States; Department of Ophthalmology, New York University School of Medicine, New York, NY, United States
| | - Janet C Rucker
- Department of Neurology, New York University School of Medicine, New York, NY, United States; Department of Ophthalmology, New York University School of Medicine, New York, NY, United States.
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20
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Mahesh KV, Bansal R, Naheed D, Tandyala N, Singh R, Takkar A. Opsoclonus Myoclonus Syndrome Due to an Ovarian Teratoma: A Case Report and Review of Literature. Neuroophthalmology 2019; 44:258-261. [PMID: 33012912 DOI: 10.1080/01658107.2019.1573374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
The importance of ovarian teratoma as a cause of opsoclonus myoclonus ataxia syndrome (OMAS) and other paraneoplastic syndromes continues to be underestimated. A strong suspicion and appropriate diagnosis remain keys to successful outcome of paraneoplastic OMAS with ovarian teratoma. We report a 14-year-old girl with paraneoplastic OMAS in association with an ovarian teratoma who improved completely following resection of tumour as well as immunotherapy and review the literature briefly.
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Affiliation(s)
- Karthik Vinay Mahesh
- Department of Neurology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Ramandeep Bansal
- Department of Gynecology and Obstetrics, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Darakhshan Naheed
- Department of Neurology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Naresh Tandyala
- Department of Neurology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Ramandeep Singh
- Department of Ophthalmology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Aastha Takkar
- Department of Neurology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
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21
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Abstract
Mathematical models of brain function are built from data covering anatomy, physiology, biophysics and behavior. In almost all cases, many possible models could fit the available data. Theoreticians make assumptions that allow them to constrain the number of possible model structures. However, a model that was more useful clinically would result if the constraints came from lesion studies in animals or clinical disorders. Here, we show a few examples of how clinical disorders have led to improvements in models. We also show a few examples of how models could lead to neural prostheses for patients. The best outcomes result when clinicians, basic scientists and theoreticians work together to understand brain function.
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Affiliation(s)
- Lance M Optican
- Laboratory of Sensorimotor Research, NEI, NIH, DHHS, Bethesda, MD, United States.
| | - Elena Pretegiani
- Laboratory of Sensorimotor Research, NEI, NIH, DHHS, Bethesda, MD, United States
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22
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Mohd Fauzi NA, Abdullah S, Tan AH, Mohd Ramli N, Tan CY, Lim SY. Relapsing encephalopathy with dancing eyes and jerky limbs. Parkinsonism Relat Disord 2019; 75:110-113. [PMID: 30846242 DOI: 10.1016/j.parkreldis.2019.02.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 02/17/2019] [Accepted: 02/18/2019] [Indexed: 10/27/2022]
Abstract
We report a case of relapsing-remitting opsoclonus-myoclonus-ataxia syndrome (OMAS) in a patient with Hashimoto's encephalopathy, diagnosed after comprehensive evaluation. OMAS as a manifestation of Hashimoto's encephalopathy has been reported once previously. It is hoped that recognition of this entity and early initiation of immunotherapy will improve clinical outcomes for patients.
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Affiliation(s)
- Nor Amelia Mohd Fauzi
- Department of Medicine, Faculty of Medicine, Universiti Teknologi MARA Sungai Buloh Campus, Selangor, Malaysia
| | - Suhailah Abdullah
- Division of Neurology, Department of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Ai Huey Tan
- Division of Neurology, Department of Medicine, University of Malaya, Kuala Lumpur, Malaysia; The Mah Pooi Soo and Tan Chin Nam Centre for Parkinson's and Related Disorders, University of Malaya, Kuala Lumpur, Malaysia
| | - Norlisah Mohd Ramli
- Department of Biomedical Imaging, University of Malaya, Kuala Lumpur, Malaysia
| | - Cheng Yin Tan
- Division of Neurology, Department of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Shen-Yang Lim
- Division of Neurology, Department of Medicine, University of Malaya, Kuala Lumpur, Malaysia; The Mah Pooi Soo and Tan Chin Nam Centre for Parkinson's and Related Disorders, University of Malaya, Kuala Lumpur, Malaysia.
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23
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Kudo Y, Sugawara E, Takahashi K, Tanaka F, Johkura K. An attempt to treat ocular flutter and opsoclonus by cerebellar magnetic stimulation. J Neurol Sci 2018; 395:119-120. [PMID: 30312902 DOI: 10.1016/j.jns.2018.10.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Revised: 09/18/2018] [Accepted: 10/03/2018] [Indexed: 11/20/2022]
Affiliation(s)
- Yosuke Kudo
- Department of Neurology, Yokohama Brain and Spine Center, Yokohama, Japan
| | - Eriko Sugawara
- Department of Neurology, Yokohama Brain and Spine Center, Yokohama, Japan
| | - Koji Takahashi
- Department of Clinical Laboratory, Yokohama Brain and Spine Center, Yokohama, Japan
| | - Fumiaki Tanaka
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Ken Johkura
- Department of Neurology, Yokohama Brain and Spine Center, Yokohama, Japan.
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24
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Oh SY, Kim JS, Dieterich M. Update on opsoclonus-myoclonus syndrome in adults. J Neurol 2018; 266:1541-1548. [PMID: 30483882 DOI: 10.1007/s00415-018-9138-7] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 11/17/2018] [Accepted: 11/21/2018] [Indexed: 01/12/2023]
Abstract
Opsoclonus-myoclonus syndrome in adults is a rare and heterogeneous disorder with the clinical features of opsoclonus, myoclonus, ataxia, and behavioral and sleep disturbances. The pathophysiology is thought to be immunological on the basis of paraneoplastic or infectious etiologies. Immunomodulatory therapies should be performed although the response may be incomplete. A number of autoantibodies have been identified against a variety of antigens, but no diagnostic immunological marker has yet been identified. This review focuses on underlying mechanisms of opsoclonus-myoclonus syndrome, including findings that have been identified recently, and provides an update on the clinical features and treatments of this condition.
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Affiliation(s)
- Sun-Young Oh
- Department of Neurology, Chonbuk National University School of Medicine, 20 Geonji-ro, Deokjin-gu, Jeonju, Chonbuk, 561-712, South Korea.
- Research Institute of Clinical Medicine of Chonbuk National University-Biomedical Research Institute of Chonbuk National University Hospital, Jeonju, South Korea.
| | - Ji-Soo Kim
- Department of Neurology, Seoul National University College of Medicine, Seoul, South Korea
- Department of Neurology, Dizziness Center, Clinical Neuroscience Center, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Marianne Dieterich
- Department of Neurology, Ludwig-Maximilians-University, Munich, Germany
- German Center for Vertigo and Balance Disorders (IFBLMU), Ludwig-Maximilians University, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
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25
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Bradshaw MJ, Gilden D, Lavin P, Sriram S. Clinical Reasoning: A 57-year-old woman with ataxia and oscillopsia: Varicella-zoster encephalitis. Neurology 2018; 87:e61-4. [PMID: 27527543 DOI: 10.1212/wnl.0000000000002981] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Michael J Bradshaw
- From the Department of Neurology (M.J.B., P.L., S.S.), Vanderbilt University Medical Center, Nashville, TN; and Department of Neurology and Immunology & Microbiology (D.G.), University of Colorado School of Medicine, Aurora.
| | - Don Gilden
- From the Department of Neurology (M.J.B., P.L., S.S.), Vanderbilt University Medical Center, Nashville, TN; and Department of Neurology and Immunology & Microbiology (D.G.), University of Colorado School of Medicine, Aurora
| | - Patrick Lavin
- From the Department of Neurology (M.J.B., P.L., S.S.), Vanderbilt University Medical Center, Nashville, TN; and Department of Neurology and Immunology & Microbiology (D.G.), University of Colorado School of Medicine, Aurora
| | - Subramaniam Sriram
- From the Department of Neurology (M.J.B., P.L., S.S.), Vanderbilt University Medical Center, Nashville, TN; and Department of Neurology and Immunology & Microbiology (D.G.), University of Colorado School of Medicine, Aurora
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26
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Paraneoplastic seesaw nystagmus and opsoclonus provides evidence for hyperexcitable reciprocally innervating mesencephalic network. J Neurol Sci 2018; 390:239-245. [DOI: 10.1016/j.jns.2018.05.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 04/28/2018] [Accepted: 05/01/2018] [Indexed: 11/18/2022]
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27
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Otero-Millan J, Optican LM, Macknik SL, Martinez-Conde S. Modeling the Triggering of Saccades, Microsaccades, and Saccadic Intrusions. Front Neurol 2018; 9:346. [PMID: 29892256 PMCID: PMC5985689 DOI: 10.3389/fneur.2018.00346] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 04/30/2018] [Indexed: 11/13/2022] Open
Abstract
When we explore a static visual scene, our eyes move in a sequence of fast eye movements called saccades, which are separated by fixation periods of relative eye stability. Based on uncertain sensory and cognitive inputs, the oculomotor system must decide, at every moment, whether to initiate a saccade or to remain in the fixation state. Even when we attempt to maintain our gaze on a small spot, small saccades, called microsaccades, intrude on fixation once or twice per second. Because microsaccades occur at the boundary of the decision to maintain fixation versus starting a saccade, they offer a unique opportunity to study the mechanisms that control saccadic triggering. Abnormal saccadic intrusions can occur during attempted fixation in patients with neurodegenerative disorders. We have implemented a model of the triggering mechanism of saccades, based on known anatomy and physiology, that successfully simulates the generation of saccades of any size-including microsaccades in healthy observers, and the saccadic intrusions that interrupt attempted fixation in parkinsonian patients. The model suggests that noisy neuronal activity in the superior colliculus controls the state of a mutually inhibitory network in the brain stem formed by burst neurons and omnipause neurons. When the neuronal activity is centered at the rostral pole, the system remains at a state of fixation. When activity is perturbed away from this center, a saccade is triggered. This perturbation can be produced either by the intent to move one's gaze or by random fluctuations in activity.
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Affiliation(s)
- Jorge Otero-Millan
- Department of Neurology, Johns Hopkins University, Baltimore, MD, United States
| | - Lance M. Optican
- Laboratory of Sensorimotor Research, National Eye Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD, United States
| | - Stephen L. Macknik
- Department of Ophthalmology, SUNY Downstate Medical Center, Brooklyn, NY, United States
- Department of Neurology, SUNY Downstate Medical Center, Brooklyn, NY, United States
- Department of Physiology and Pharmacology, SUNY Downstate Medical Center, Brooklyn, NY, United States
| | - Susana Martinez-Conde
- Department of Ophthalmology, SUNY Downstate Medical Center, Brooklyn, NY, United States
- Department of Neurology, SUNY Downstate Medical Center, Brooklyn, NY, United States
- Department of Physiology and Pharmacology, SUNY Downstate Medical Center, Brooklyn, NY, United States
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28
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Zee DS. A neurologist and ataxia: using eye movements to learn about the cerebellum. CEREBELLUM & ATAXIAS 2018; 5:2. [PMID: 29445510 PMCID: PMC5804057 DOI: 10.1186/s40673-018-0081-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 01/25/2018] [Indexed: 11/22/2022]
Abstract
The cerebellum, its normal functions and its diseases, and especially its relation to the control of eye movements, has been at the heart of my academic career. Here I review how this came about, with an emphasis on epiphanies, "tipping points" and the influences of mentors, colleagues and trainees. I set a path for young academicians, both clinicians and basic scientists, with some guidelines for developing a productive and rewarding career in neuroscience.
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Affiliation(s)
- David S. Zee
- Departments of Neurology, Ophthalamology, Otolaryngology-Head and Neck Surgery, and Neuroscience, The Johns Hopkins University School of Medicine, The Johns Hopkins Hospital, Path 2-210, Baltimore, MD 21287 USA
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29
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Tarnutzer AA, Straumann D, Salman MS. Neuro-ophthalmologic assessment and investigations in children and adults with cerebellar diseases. THE CEREBELLUM: FROM EMBRYOLOGY TO DIAGNOSTIC INVESTIGATIONS 2018; 154:305-327. [DOI: 10.1016/b978-0-444-63956-1.00019-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Optican LM, Pretegiani E. What stops a saccade? Philos Trans R Soc Lond B Biol Sci 2017; 372:rstb.2016.0194. [PMID: 28242728 DOI: 10.1098/rstb.2016.0194] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/05/2016] [Indexed: 11/12/2022] Open
Abstract
Rapid movements to a target are ballistic; they usually do not last long enough for visual feedback about errors to influence them. Yet, the brain is not simply precomputing movement trajectory. Classical models of movement control involve a feedback loop that subtracts 'where we are now' from 'where we want to be'. That difference is an internal motor error. The feedback loop reduces this error until it reaches zero, stopping the movement. However, neurophysiological studies have shown that movements controlled by the cerebrum (e.g. arm and head movements) and those controlled by the brain stem (e.g. tongue and eye movements) are also controlled, in parallel, by the cerebellum. Thus, there may not be a single error control loop. We propose an alternative to feedback error control, wherein the cerebellum uses adaptive, velocity feedback, integral control to stop the movement on target.This article is part of the themed issue 'Movement suppression: brain mechanisms for stopping and stillness'.
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Affiliation(s)
- Lance M Optican
- Laboratory of Sensorimotor Research, NEI, NIH, 49 Convent Drive, Room 2A50, Bethesda, MD 20892, USA
| | - Elena Pretegiani
- Laboratory of Sensorimotor Research, NEI, NIH, 49 Convent Drive, Room 2A50, Bethesda, MD 20892, USA
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Nakamagoe K, Nohara S, Takahashi Y, Takiguchi M, Kawakami R, Koganezawa T, Tamaoka A. The Successful Application of Plasmapheresis in the Treatment of a Patient with Opsoclonus and Autoantibodies to Glutamate Receptor δ2. Intern Med 2017; 56:2773-2778. [PMID: 28924105 PMCID: PMC5675942 DOI: 10.2169/internalmedicine.6771-15] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Glutamate receptor δ2 (GluRδ2) is expressed in the neuronal postsynaptic densities at the junctions between the Purkinje cells and the parallel fibers. Recent reports have described patients with opsoclonus who possess anti-GluRδ2 antibodies. We report the case of a 53-year-old man with opsoclonus whose cerebrospinal fluid was positive for anti-GluRδ2 antibodies. Electronystagmography revealed abnormal sinusoidal eye movements, which were definitively identified as opsoclonus. The frequency and amplitude of saccadic oscillations diminished after plasmapheresis (PE). The patient's opsoclonus was altered after PE, suggesting that anti-GluRδ2 antibodies may act on the saccade generator in the brainstem via the cerebellum and that they may be involved in the onset of opsoclonus.
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Affiliation(s)
- Kiyotaka Nakamagoe
- Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Japan
| | - Seitaro Nohara
- Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Japan
| | - Yukitoshi Takahashi
- National Epilepsy Center, Shizuoka Institute of Epilepsy and Neurological Disorders, Japan
| | - Mao Takiguchi
- Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Japan
| | - Rio Kawakami
- Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Japan
| | - Tadachika Koganezawa
- Department of Physiology, Division of Biomedical Science, Faculty of Medicine, University of Tsukuba, Japan
| | - Akira Tamaoka
- Department of Neurology, Division of Clinical Medicine, Faculty of Medicine, University of Tsukuba, Japan
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32
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Optican LM, Pretegiani E. A GABAergic Dysfunction in the Olivary-Cerebellar-Brainstem Network May Cause Eye Oscillations and Body Tremor. II. Model Simulations of Saccadic Eye Oscillations. Front Neurol 2017; 8:372. [PMID: 28824529 PMCID: PMC5543285 DOI: 10.3389/fneur.2017.00372] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Accepted: 07/17/2017] [Indexed: 01/15/2023] Open
Abstract
Eye and body oscillations are shared features of several neurological diseases, yet their pathophysiology remains unclear. Recently, we published a report on two tennis players with a novel presentation of eye and body oscillations following self-administration of performance-enhancing substances. Opsoclonus/flutter and limb tremor were diagnosed in both patients. Common causes of opsoclonus/flutter were excluded. High-resolution eye movement recordings from one patient showed novel spindle-shaped, asymmetric saccadic oscillations (at ~3.6 Hz) and ocular tremor (~40-60 Hz). Based on these findings, we proposed that the oscillations are the result of increased GABAA receptor sensitivity in a circuit involving the cerebellum (vermis and fastigial nuclei), the inferior olives, and the brainstem saccade premotor neurons (excitatory and inhibitory burst neurons, and omnipause neurons). We present a mathematical model of the saccadic system, showing that the proposed dysfunction in the network can reproduce the types of saccadic oscillations seen in these patients.
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Affiliation(s)
- Lance M. Optican
- Laboratory of Sensorimotor Research, IRP, National Eye Institute, National Institutes of Health, Bethesda, MD, United States
| | - Elena Pretegiani
- Laboratory of Sensorimotor Research, IRP, National Eye Institute, National Institutes of Health, Bethesda, MD, United States
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33
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Jesus-Ribeiro J, Farinha C, Amorim M, Matos A, Reis A, Lemos J, Castelo-Branco M, Januário C. Visual and ocular motor function in the atypical form of neurodegeneration with brain iron accumulation type I. Br J Ophthalmol 2017; 102:102-108. [PMID: 28487376 DOI: 10.1136/bjophthalmol-2017-310181] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 04/04/2017] [Accepted: 04/06/2017] [Indexed: 11/04/2022]
Abstract
BACKGROUND/AIMS Neurodegeneration with brain iron accumulation (NBIA) type I is a rare disease that can be divided into a classical or atypical variant, according to age of onset and clinical pattern. Neuro-ophthalmological involvement has been documented in the classical variant but only anecdotically in the atypical variant. We sought to describe the visual and ocular motor function in patients with atypical form of NBIA type I. METHODS Cross-sectional study, including patients with genetically confirmed NBIA type I and classified as atypical variant, who underwent ophthalmological examination with best corrected visual acuity (BCVA), optical coherence tomography (OCT), fundus autofluorescence (FAF), electroretinography (ERG), visual evoked potentials (VEP) and video-oculography. RESULTS Seven patients with a mean BCVA of 0.12±0.14 logMAR were included. Only two patients showed structural evidence of advanced retinopathy in OCT and FAF, and there were no cases of optic atrophy. ERG data, however, showed abnormal scotopic and/or photopic responses in all patients. VEP were normal in all three patients. Ocular fixation was markedly unstable (eg, increased rate of saccadic pulses) in the majority of patients (5). Additional mild ocular motor disturbances included low gain pursuit (2), hypermetric saccades (1), low gain optokinetic (2) and caloric and rotatory responses (3). CONCLUSION Functional retinal changes associated with marked instability of ocular fixation should be included in the clinical spectrum of NBIA, particularly in the atypical form.
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Affiliation(s)
- Joana Jesus-Ribeiro
- Department of Neurology, Coimbra University Hospital Center, Coimbra, Portugal
| | - Cláudia Farinha
- Department of Ophthalmology, Coimbra University Hospital Center, Coimbra, Portugal.,Association for Innovation and Biomedical Research on Light and Image, Coimbra, Portugal
| | - Margarida Amorim
- Department of Otorhinolaryngology, Coimbra University Hospital Center, Coimbra, Portugal
| | - Anabela Matos
- Department of Neurology, Coimbra University Hospital Center, Coimbra, Portugal.,Department of Neurophysiology, Coimbra University Hospital Center, Coimbra, Portugal
| | - Aldina Reis
- Institute for Biomedical Imaging and Life Sciences, Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - João Lemos
- Department of Neurology, Coimbra University Hospital Center, Coimbra, Portugal
| | - Miguel Castelo-Branco
- Institute for Biomedical Imaging and Life Sciences, Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Cristina Januário
- Department of Neurology, Coimbra University Hospital Center, Coimbra, Portugal.,Faculty of Medicine, University of Coimbra, Coimbra, Portugal
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34
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Colagiorgio P, Versino M, Colnaghi S, Quaglieri S, Manfrin M, Zamaro E, Mantokoudis G, Zee DS, Ramat S. New insights into vestibular-saccade interaction based on covert corrective saccades in patients with unilateral vestibular deficits. J Neurophysiol 2017; 117:2324-2338. [PMID: 28404827 DOI: 10.1152/jn.00864.2016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 04/10/2017] [Accepted: 04/10/2017] [Indexed: 11/22/2022] Open
Abstract
In response to passive high-acceleration head impulses, patients with low vestibulo-ocular reflex (VOR) gains often produce covert (executed while the head is still moving) corrective saccades in the direction of deficient slow phases. Here we examined 23 patients using passive, and 9 also active, head impulses with acute (< 10 days from onset) unilateral vestibular neuritis and low VOR gains. We found that when corrective saccades are larger than 10°, the slow-phase component of the VOR is inhibited, even though inhibition increases further the time to reacquire the fixation target. We also found that 1) saccades are faster and more accurate if the residual VOR gain is higher, 2) saccades also compensate for the head displacement that occurs during the saccade, and 3) the amplitude-peak velocity relationship of the larger corrective saccades deviates from that of head-fixed saccades of the same size. We propose a mathematical model to account for these findings hypothesizing that covert saccades are driven by a desired gaze position signal based on a prediction of head displacement using vestibular and extravestibular signals, covert saccades are controlled by a gaze feedback loop, and the VOR command is modulated according to predicted saccade amplitude. A central and novel feature of the model is that the brain develops two separate estimates of head rotation, one for generating saccades while the head is moving and the other for generating slow phases. Furthermore, while the model was developed for gaze-stabilizing behavior during passively induced head impulses, it also simulates both active gaze-stabilizing and active gaze-shifting eye movements.NEW & NOTEWORTHY During active or passive head impulses while fixating stationary targets, low vestibulo-ocular gain subjects produce corrective saccades when the head is still moving. The mechanisms driving these covert saccades are poorly understood. We propose a mathematical model showing that the brain develops two separate estimates of head rotation: a lower level one, presumably in the vestibular nuclei, used to generate the slow-phase component of the response, and a higher level one, within a gaze feedback loop, used to drive corrective saccades.
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Affiliation(s)
- Paolo Colagiorgio
- Department of Electrical, Computer and Biomedical Engineering, University of Pavia, Pavia, Italy
| | - Maurizio Versino
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy.,Laboratory of Neuro-otology and Neuro-ophthalmology, C. Mondino National Neurological Institute, Pavia, Italy
| | - Silvia Colnaghi
- Department of Public Health, Experimental and Forensic Medicine, University of Pavia, Pavia, Italy.,Inter-Department Multiple Sclerosis Research Centre, C. Mondino National Neurological Institute, Pavia, Italy
| | - Silvia Quaglieri
- UOC Otorinolaringoiatria, Fondazione IRCCS San Matteo and University of Pavia, Pavia, Italy
| | - Marco Manfrin
- UOC Otorinolaringoiatria, Fondazione IRCCS San Matteo and University of Pavia, Pavia, Italy
| | - Ewa Zamaro
- Department of Otorhinolaryngology, Head and Neck Surgery, lnselspital, Bern University Hospital, University of Bern, Bern, Switzerland; and
| | - Georgios Mantokoudis
- Department of Otorhinolaryngology, Head and Neck Surgery, lnselspital, Bern University Hospital, University of Bern, Bern, Switzerland; and
| | - David S Zee
- Department of Neurology, Otolaryngology-Head and Neck Surgery, Neuroscience, Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Stefano Ramat
- Department of Electrical, Computer and Biomedical Engineering, University of Pavia, Pavia, Italy;
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35
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Oh SY, Boegle R, Eulenburg PZ, Ertl M, Kim JS, Dieterich M. Longitudinal multi-modal neuroimaging in opsoclonus–myoclonus syndrome. J Neurol 2017; 264:512-519. [DOI: 10.1007/s00415-016-8389-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 12/20/2016] [Accepted: 12/27/2016] [Indexed: 10/20/2022]
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36
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Are high lags of accommodation in myopic children due to motor deficits? Vision Res 2016; 130:9-21. [PMID: 27876513 DOI: 10.1016/j.visres.2016.11.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Revised: 11/09/2016] [Accepted: 11/14/2016] [Indexed: 11/21/2022]
Abstract
Children with a progressing myopia exhibit an abnormal pattern of high accommodative lags coupled with high accommodative convergence (AC/A) and high accommodative adaptation. This is not predicted by the current models of accommodation and vergence. Reduced accommodative plant gain and reduced sensitivity to blur have been suggested as potential causes for this abnormal behavior. These etiologies were tested by altering parameters (sensory, controller and plant gains) in the Simulink model of accommodation. Predictions were then compared to the static and dynamic blur accommodation (BA) measures taken using a Badal optical system on 12 children (6 emmetropes and 6 myopes, 8-13years) and 6 adults (20-35years). Other critical parameters such as CA/C, AC/A, and accommodative adaptation were also measured. Usable BA responses were classified as either typical or atypical. Typical accommodation data confirmed the abnormal pattern of myopia along with an unchanged CA/C. Main sequence relationship remained invariant between myopic and nonmyopic children. An overall reduction was noted in the response dynamics such as peak velocity and acceleration with age. Neither a reduced plant gain nor reduced blur sensitivity could predict the abnormal accommodative behavior. A model adjustment reflecting a reduced accommodative sensory gain (ASG) coupled with an increased AC cross-link gain and reduced vergence adaptive gain does predict the empirical findings. Empirical measures also showed a greater frequency of errors in accommodative response generation (atypical responses) in both myopic and control children compared to adults.
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37
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Shaikh AG, Wilmot G. Opsoclonus in a patient with increased titers of anti-GAD antibody provides proof for the conductance-based model of saccadic oscillations. J Neurol Sci 2016; 362:169-73. [PMID: 26944142 DOI: 10.1016/j.jns.2016.01.038] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 12/20/2015] [Accepted: 01/18/2016] [Indexed: 11/18/2022]
Abstract
Paucity in gamma-amino butyric acid (GABA) due to blockage in the action of glutamic acid decarboxylase (GAD), as seen in the syndrome of anti-GAD antibody, causes adult onset cerebellar ataxia, muscle rigidity, and episodic spasms. Downbeat nystagmus, saccadic dysmetria, impaired ocular pursuit, and impaired cancelation of vestibular ocular reflex are typical ocular motor deficits in patients with syndrome of anti-GAD antibody. We describe opsoclonus, in addition to downbeat nystagmus, in a patient with increased titers of anti-GAD antibody. Paucity in GABA leading to disinhibition to Purkinje target neurons at deep cerebellar and vestibular nuclei might have caused downbeat nystagmus in our patient. Anti-GAD antibody can also increase levels of glutamate the precursor of GABA and the substrate for the action of GAD. We propose that opsoclonus might be due to increased levels of glutamate and subsequent hyperexcitability of excitatory and inhibitory burst neurons leading to reverberation in their reciprocally innervating circuit.
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Affiliation(s)
- Aasef G Shaikh
- Department of Neurology, Case Western Reserve University, Cleveland, OH, United States; Daroff-DelOsso Ocular Motility Laboratory and Neurology Service, Cleveland VA Medical Center, Cleveland, OH, United States.
| | - George Wilmot
- Department of Neurology, Emory University, Atlanta, GA, United States
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38
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Termsarasab P, Thammongkolchai T, Rucker JC, Frucht SJ. The diagnostic value of saccades in movement disorder patients: a practical guide and review. JOURNAL OF CLINICAL MOVEMENT DISORDERS 2015; 2:14. [PMID: 26788350 PMCID: PMC4710978 DOI: 10.1186/s40734-015-0025-4] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 09/01/2015] [Indexed: 12/11/2022]
Abstract
Saccades are rapid eye movements designed to shift the fovea to objects of visual interest. Abnormalities of saccades offer important clues in the diagnosis of a number of movement disorders. In this review, we explore the anatomy of horizontal and vertical saccades, discuss practical aspects of their examination, and review how saccadic abnormalities in hyperkinetic and hypokinetic movement disorders aid in diagnosis, with video demonstration of classic examples. Documentation of the ease of saccade initiation, range of motion and conjugacy of saccades, speed and accuracy of saccades, dynamic saccadic trajectory, and the presence or absence of saccadic intrusions and oscillations are important components of this exam. We also provide a practical algorithm to demonstrate the value of saccades in the differential diagnosis of the movement disorders patient.
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Affiliation(s)
- Pichet Termsarasab
- Movement Disorder Division, Department of Neurology, Icahn School of Medicine at Mount Sinai, 5 East 98th St, New York, 10029 USA
| | | | - Janet C Rucker
- Division of Neuro-ophthalmology, Department of Neurology, New York University School of Medicine, New York, USA
| | - Steven J Frucht
- Movement Disorder Division, Department of Neurology, Icahn School of Medicine at Mount Sinai, 5 East 98th St, New York, 10029 USA
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39
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Kobayashi M. Unidirectional ocular flutter: report of a case with abnormal saccadic characteristics. Neurol Sci 2014; 36:1273-6. [DOI: 10.1007/s10072-014-2006-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Accepted: 11/06/2014] [Indexed: 11/25/2022]
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40
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Bonnet C, Rusz J, Megrelishvili M, Sieger T, Matoušková O, Okujava M, Brožová H, Nikolai T, Hanuška J, Kapianidze M, Mikeladze N, Botchorishvili N, Khatiashvili I, Janelidze M, Serranová T, Fiala O, Roth J, Bergquist J, Jech R, Rivaud-Péchoux S, Gaymard B, Růžička E. Eye movements in ephedrone-induced parkinsonism. PLoS One 2014; 9:e104784. [PMID: 25117825 PMCID: PMC4130591 DOI: 10.1371/journal.pone.0104784] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2014] [Accepted: 07/16/2014] [Indexed: 12/02/2022] Open
Abstract
Patients with ephedrone parkinsonism (EP) show a complex, rapidly progressive, irreversible, and levodopa non-responsive parkinsonian and dystonic syndrome due to manganese intoxication. Eye movements may help to differentiate parkinsonian syndromes providing insights into which brain networks are affected in the underlying disease, but they have never been systematically studied in EP. Horizontal and vertical eye movements were recorded in 28 EP and compared to 21 Parkinson's disease (PD) patients, and 27 age- and gender-matched healthy subjects using standardized oculomotor tasks with infrared videooculography. EP patients showed slow and hypometric horizontal saccades, an increased occurrence of square wave jerks, long latencies of vertical antisaccades, a high error rate in the horizontal antisaccade task, and made more errors than controls when pro- and antisaccades were mixed. Based on oculomotor performance, a direct differentiation between EP and PD was possible only by the velocity of horizontal saccades. All remaining metrics were similar between both patient groups. EP patients present extensive oculomotor disturbances probably due to manganese-induced damage to the basal ganglia, reflecting their role in oculomotor system.
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Affiliation(s)
- Cecilia Bonnet
- Department of Neurology and Centre of Clinical Neuroscience, Charles University in Prague, 1st Faculty of Medicine and General University Hospital, Prague, Czech Republic
| | - Jan Rusz
- Department of Neurology and Centre of Clinical Neuroscience, Charles University in Prague, 1st Faculty of Medicine and General University Hospital, Prague, Czech Republic; Department of Circuit Theory, Faculty of Electrical Engineering, Czech Technical University, Prague, Czech Republic
| | - Marika Megrelishvili
- Department of Neurology, S. Khechinashvili University Clinic, Tbilisi, Georgia; Institute of Medical Research, Ilia State University, Tbilisi, Georgia
| | - Tomáš Sieger
- Department of Neurology and Centre of Clinical Neuroscience, Charles University in Prague, 1st Faculty of Medicine and General University Hospital, Prague, Czech Republic; Department of Cybernetics, Faculty of Electrical Engineering, Czech Technical University, Prague, Czech Republic
| | - Olga Matoušková
- Department of Neurology and Centre of Clinical Neuroscience, Charles University in Prague, 1st Faculty of Medicine and General University Hospital, Prague, Czech Republic; Institute of Pharmacology, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Prague, Czech Republic
| | | | - Hana Brožová
- Department of Neurology and Centre of Clinical Neuroscience, Charles University in Prague, 1st Faculty of Medicine and General University Hospital, Prague, Czech Republic
| | - Tomáš Nikolai
- Department of Neurology and Centre of Clinical Neuroscience, Charles University in Prague, 1st Faculty of Medicine and General University Hospital, Prague, Czech Republic
| | - Jaromír Hanuška
- Department of Neurology and Centre of Clinical Neuroscience, Charles University in Prague, 1st Faculty of Medicine and General University Hospital, Prague, Czech Republic
| | - Mariam Kapianidze
- Department of Neurology, S. Khechinashvili University Clinic, Tbilisi, Georgia
| | - Nina Mikeladze
- Department of Neurology, S. Khechinashvili University Clinic, Tbilisi, Georgia
| | - Nazi Botchorishvili
- Department of Neurology, S. Khechinashvili University Clinic, Tbilisi, Georgia
| | - Irine Khatiashvili
- Department of Neurology, S. Khechinashvili University Clinic, Tbilisi, Georgia
| | - Marina Janelidze
- Department of Neurology, S. Khechinashvili University Clinic, Tbilisi, Georgia
| | - Tereza Serranová
- Department of Neurology and Centre of Clinical Neuroscience, Charles University in Prague, 1st Faculty of Medicine and General University Hospital, Prague, Czech Republic
| | - Ondřej Fiala
- Department of Neurology and Centre of Clinical Neuroscience, Charles University in Prague, 1st Faculty of Medicine and General University Hospital, Prague, Czech Republic
| | - Jan Roth
- Department of Neurology and Centre of Clinical Neuroscience, Charles University in Prague, 1st Faculty of Medicine and General University Hospital, Prague, Czech Republic
| | - Jonas Bergquist
- Analytical Chemistry and Neurochemistry, Department of Chemistry, Biomedical Center and SciLife Lab, Uppsala University, Uppsala, Sweden
| | - Robert Jech
- Department of Neurology and Centre of Clinical Neuroscience, Charles University in Prague, 1st Faculty of Medicine and General University Hospital, Prague, Czech Republic
| | - Sophie Rivaud-Péchoux
- CRICM UPMC/INSERM UMR_S975, CNRS UMR7225, ICM, Pitié-Salpêtrière Hospital, Paris, France; Pierre et Marie Curie Paris-6 University, Paris, France
| | - Bertrand Gaymard
- CRICM UPMC/INSERM UMR_S975, CNRS UMR7225, ICM, Pitié-Salpêtrière Hospital, Paris, France; Pierre et Marie Curie Paris-6 University, Paris, France
| | - Evžen Růžička
- Department of Neurology and Centre of Clinical Neuroscience, Charles University in Prague, 1st Faculty of Medicine and General University Hospital, Prague, Czech Republic
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Abstract
Saccadic oscillations are continuous back-to-back saccades that cause excessive image motion across fovea and threaten clear vision. Acquired processes, related to immune or metabolic mechanisms, are common culprits. Saccadic oscillations are also seen in degenerative cerebellar disease or as a part of a familial syndrome of saccadic oscillations and limb tremor. Some normal individuals have innate ability to voluntarily trigger saccadic oscillations (i.e. voluntary nystagmus). Contemporary theory for the pathogenesis for saccadic oscillations has emphasized hyperexcitable or disinhibited state of the brainstem saccadic burst neuron membrane. This review discusses etiologies and treatment of saccadic oscillations in light of novel cell membrane based theory.
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Affiliation(s)
- Aasef G Shaikh
- Department of Neurology, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, OH
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42
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Kalman filtering naturally accounts for visually guided and predictive smooth pursuit dynamics. J Neurosci 2013; 33:17301-13. [PMID: 24174663 DOI: 10.1523/jneurosci.2321-13.2013] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The brain makes use of noisy sensory inputs to produce eye, head, or arm motion. In most instances, the brain combines this sensory information with predictions about future events. Here, we propose that Kalman filtering can account for the dynamics of both visually guided and predictive motor behaviors within one simple unifying mechanism. Our model relies on two Kalman filters: (1) one processing visual information about retinal input; and (2) one maintaining a dynamic internal memory of target motion. The outputs of both Kalman filters are then combined in a statistically optimal manner, i.e., weighted with respect to their reliability. The model was tested on data from several smooth pursuit experiments and reproduced all major characteristics of visually guided and predictive smooth pursuit. This contrasts with the common belief that anticipatory pursuit, pursuit maintenance during target blanking, and zero-lag pursuit of sinusoidally moving targets all result from different control systems. This is the first instance of a model integrating all aspects of pursuit dynamics within one coherent and simple model and without switching between different parallel mechanisms. Our model suggests that the brain circuitry generating a pursuit command might be simpler than previously believed and only implement the functional equivalents of two Kalman filters whose outputs are optimally combined. It provides a general framework of how the brain can combine continuous sensory information with a dynamic internal memory and transform it into motor commands.
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Matalia J, J Chillal G, Brodsky MC. Positional vertical opsoclonus: a transient phenomenon in normal healthy twins. J AAPOS 2013; 17:537-8. [PMID: 24054037 DOI: 10.1016/j.jaapos.2013.05.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 04/15/2013] [Accepted: 05/04/2013] [Indexed: 11/25/2022]
Abstract
Opsoclonus is characterized by rapid bursts of involuntary, multidirectional, saccades without an intersaccadic interval. Three types of opsoclonus that occur in infancy have been identified, 2 of which are associated with a systemic or neurologic condition. The third is a benign condition that occurs transiently in healthy neonates and preterm babies. We report a case of 2 healthy twins who presented with transient opsoclonus, which was confined only to the vertical plane and manifested only in a supine position. Opsoclonus disappeared when the cheek was tapped. These eye movements began at 3 months and completely resolved by 6 months of age.
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Affiliation(s)
- Jyoti Matalia
- Department of Pediatric Ophthalmology, Narayana Nethralaya 2, Narayana Health City, Bommsandra, Bangalore, India.
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Daye PM, Optican LM, Roze E, Gaymard B, Pouget P. Neuromimetic model of saccades for localizing deficits in an atypical eye-movement pathology. J Transl Med 2013; 11:125. [PMID: 23694702 PMCID: PMC3672089 DOI: 10.1186/1479-5876-11-125] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Accepted: 05/15/2013] [Indexed: 11/30/2022] Open
Abstract
Background When patients with ocular motor deficits come to the clinic, in numerous situations it is hard to relate their behavior to one or several deficient neural structures. We sought to demonstrate that neuromimetic models of the ocular motor brainstem could be used to test assumptions of the neural deficits linked to a patient’s behavior. Methods Eye movements of a patient with unexplained neurological pathology were recorded. We analyzed the patient’s behavior in terms of a neuromimetic saccadic model of the ocular motor brainstem to formulate a pathophysiological hypothesis. Results Our patient exhibited unusual ocular motor disorders including increased saccadic peak velocities (up to ≈1000 deg/s), dynamic saccadic overshoot, left-right asymmetrical post-saccadic drift and saccadic oscillations. We show that our model accurately reproduced the observed disorders allowing us to hypothesize that those disorders originated from a deficit in the cerebellum. Conclusion Our study suggests that neuromimetic models could be a good complement to traditional clinical tools. Our behavioral analyses combined with the model simulations localized four different features of abnormal eye movements to cerebellar dysfunction. Importantly, this assumption is consistent with clinical symptoms.
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Affiliation(s)
- Pierre M Daye
- Laboratory of Sensorimotor Research, National Institutes of Health, Bethesda, Maryland, USA.
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Duval C. Ocular tremor in Parkinson's disease: The debate is not over. Mov Disord 2013; 28:713-4. [DOI: 10.1002/mds.25514] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 04/02/2013] [Accepted: 04/16/2013] [Indexed: 11/10/2022] Open
Affiliation(s)
- Christian Duval
- Centre de Recherche de l'Institut Universitaire de Gériatrie de Montréal; Montréal Québec Canada
- Département de Kinanthropologie; Université du Québec à Montréal; Montréal Québec Canada
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Rosenberg ML, Fernandez-Villa A, McKinney J. Stimulus Sensitive Constant Micro Macro Square-Wave Jerks in a Comatose Patient. Neuroophthalmology 2013; 37:73-77. [PMID: 28163759 DOI: 10.3109/01658107.2012.753916] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2011] [Revised: 09/09/2012] [Accepted: 09/24/2012] [Indexed: 11/13/2022] Open
Abstract
Saccades are generally thought of as being cortically generated and not seen in comatose patients. We describe a patient, comatose secondary to a large intracerebral hemorrhage, who developed constant rhythmic small amplitude square-wave jerks with an intersaccadic interval of 130 ms. Despite the patient's comatose state the eye movements would stop transiently in response to auditory or tactile stimulation and then quickly regain their previous amplitude. The case suggests that the presence of repetitive saccades in the form of square-wave jerks does not indicate consciousness.
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Affiliation(s)
| | | | - James McKinney
- UMDNJ-Robert Wood Johnson Medical School (JM) New Brunswick NJ USA
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Salazar R, Mehta C, Zaher N, Miller D. Opsoclonus as a manifestation of Hashimoto’s encephalopathy. J Clin Neurosci 2012; 19:1465-6. [DOI: 10.1016/j.jocn.2012.02.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2012] [Accepted: 02/26/2012] [Indexed: 10/28/2022]
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Jen JC, Lopez I, Baloh RW. Opsoclonus: Clinical and immunological features. J Neurol Sci 2012; 320:61-5. [DOI: 10.1016/j.jns.2012.06.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Revised: 06/12/2012] [Accepted: 06/27/2012] [Indexed: 11/26/2022]
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Glycine receptor antibodies are detected in progressive encephalomyelitis with rigidity and myoclonus (PERM) but not in saccadic oscillations. J Neurol 2012; 259:1566-73. [PMID: 22215239 DOI: 10.1007/s00415-011-6377-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2011] [Accepted: 12/12/2011] [Indexed: 10/14/2022]
Abstract
Glycine receptor (GlyR) antibodies were recently identified in a few patients with progressive encephalomyelitis with rigidity and myoclonus (PERM); none of these patients had antibodies against glutamic acid decarboxylase (GAD). An inhibitory glycinergic transmission defect has also been implicated in the mechanism underlying saccadic oscillations, including ocular flutter or opsoclonus; GlyR antibodies have not been reported in these patients. The purpose was to determine whether GlyR antibodies are found in patients with PERM, ocular flutter syndrome (OFS), and opsoclonus-myoclonus syndrome (OMS). GlyR antibodies were first measured in archived sera and CSF from five patients, including one patient with GAD antibody-positive PERM, two patients with OFS, and two patients with OMS. GlyR antibodies were also measured in archived sera from nine other adult patients with OMS. GlyR antibodies and GAD antibodies were both found at high titers in the serum and CSF of the patient with PERM, and their levels paralleled disease activity over time. GlyR antibodies were not found at significant levels in 13 patients with saccadic oscillations. GlyR and GAD antibodies can co-exist in PERM and follow the clinical course. Although saccadic oscillations are a feature of this condition, GlyR antibodies are not commonly found in patients with isolated saccadic oscillations.
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