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Progress in Brain Research 2019Opsoclonus/flutter (O/F) is a rare disorder of the saccadic system. Previously, we modeled O/F that developed in a patient following abuse of anabolic steroids. That...
Opsoclonus/flutter (O/F) is a rare disorder of the saccadic system. Previously, we modeled O/F that developed in a patient following abuse of anabolic steroids. That model, as in all models of the saccadic system, generates commands to make a change in eye position. Recently, we saw a patient who developed a unique form of opsoclonus following a concussion. The patient had postsaccadic ocular flutter in both directions of gaze, and opsoclonus during fixation and pursuit in the left hemifield. A new model of the saccadic system is needed to account for this gaze-position dependent O/F. We started with our prior model, which contains two key elements, mutual inhibition between inhibitory burst neurons on both sides and a prolonged reactivation time of the omnipause neurons (OPNs). We included new inputs to the OPNs from the nucleus prepositus hypoglossi and the frontal eye fields, which contain position-dependent neurons. This provides a mechanism for delaying OPN reactivation, and creating a gaze-position dependence. A simplified pursuit system was also added, the output of which inhibits the OPNs, providing a mechanism for gaze-dependence during pursuit. The rest of the model continues to generate a command to change eye position.
Topics: Brain Stem; Fixation, Ocular; Frontal Lobe; Humans; Models, Neurological; Neural Inhibition; Ocular Motility Disorders; Saccades
PubMed: 31325994
DOI: 10.1016/bs.pbr.2019.01.002 -
Journal of Neuro-ophthalmology : the... Jun 2022The opsoclonus-myoclonus-ataxia syndrome (OMAS) represents a pathophysiology and diagnostic challenge. Although the diverse etiologies likely share a common mechanism to...
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.
Topics: COVID-19; Cerebellar Ataxia; Clonazepam; Female; Humans; Immunoglobulin G; Methylprednisolone Hemisuccinate; Ocular Motility Disorders; Opsoclonus-Myoclonus Syndrome; RNA, Viral; Receptors, GABA-A; Rituximab; SARS-CoV-2
PubMed: 34974489
DOI: 10.1097/WNO.0000000000001498 -
Journal of Neuroimmunology Nov 2020Opsoclonus is an ocular motility disorder characterized by spontaneous, arrhythmic conjugate saccades of varying amplitude occurring in all directions of gaze without...
Opsoclonus is an ocular motility disorder characterized by spontaneous, arrhythmic conjugate saccades of varying amplitude occurring in all directions of gaze without normal intersaccadic interval. Etiological spectrum of opsoclonus encompasses paraneoplastic and neoplastic conditions, infectious and para-infectious encephalitis, autoimmune, metabolic and toxic encephalopathies, drugs, motor neuron diseases, multiple sclerosis and rarely neuromyelitis optica spectrum disorder (NMOSD). Opsoclonus has never been reported as a presenting manifestation heralding NMOSD. We herein report a previously healthy 37-year-old Asian Indian woman who presented with oscillopsia and opsoclonus, followed, 12 h later, by right-sided hemiparesis, right-sided appendicular ataxia, and left-sided lower motor neuron type facial palsy and dysarthria. Brain magnetic resonance imaging revealed hyperintense lesions in brainstem and thalamus in T2-weighted and fluid attenuated inversion recovery-weighted images, quite suggestive of NMOSD. Serum and cerebrospinal fluid samples were positive for anti-aquaporin-4 antibodies, which clinched the diagnosis of seropositive NMOSD. After completion of a course of intravenous methylprednisolone 1 g/day for 5 days, her opsoclonus disappeared completely. There was significant improvement in her speech and weakness within the first week of therapy and no objective deficit after day 20 of admission. After one-and-a-half-year follow-up, the patient was maintaining well on rituximab as secondary prophylaxis without any further attack. Our case highlights that isolated opsoclonus can be the presenting feature of NMOSD.
Topics: Adult; Anti-Inflammatory Agents; Female; Humans; Immunologic Factors; Methylprednisolone; Neuromyelitis Optica; Ocular Motility Disorders; Rituximab
PubMed: 32956950
DOI: 10.1016/j.jneuroim.2020.577394 -
Cerebellum (London, England) Apr 2024Opsoclonus refers to saccadic oscillations without an intersaccadic interval occurring in multiple planes. Opsoclonus mostly indicates dysfunction of the brainstem or...
Opsoclonus refers to saccadic oscillations without an intersaccadic interval occurring in multiple planes. Opsoclonus mostly indicates dysfunction of the brainstem or cerebellum. We report opsoclonus induced by horizontal head-shaking without other signs of brainstem or cerebellar dysfunction in two patients with vestibular migraine (VM). The development of opsoclonus after horizontal head-shaking indicates unstable or hyperactive neural circuits between the excitatory and inhibitory saccadic premotor burst neurons in these patients with VM.
Topics: Humans; Ocular Motility Disorders; Saccades; Brain Stem; Cerebellum; Vertigo; Migraine Disorders
PubMed: 37227606
DOI: 10.1007/s12311-023-01571-z -
Cerebellum (London, England) Oct 2021We 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...
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.
Topics: Humans; Multiple System Atrophy; Nystagmus, Pathologic; Ocular Motility Disorders; Saccades; Vestibule, Labyrinth
PubMed: 31838647
DOI: 10.1007/s12311-019-01090-w -
Revue Neurologique 1991A 32 year old patient with unexplained cough developed an opsoclonus-ataxic-myoclonic syndrome. Chest X-ray film were normal at this onset but became pathologic, and the... (Review)
Review
A 32 year old patient with unexplained cough developed an opsoclonus-ataxic-myoclonic syndrome. Chest X-ray film were normal at this onset but became pathologic, and the diagnosis of multisystemic sarcoidosis was made. The possibility of sarcoidosis being the cause of the opsoclonus is discussed.
Topics: Adult; Ataxia; Humans; Male; Myoclonus; Nervous System Diseases; Ocular Motility Disorders; Sarcoidosis
PubMed: 1763259
DOI: No ID Found -
European Journal of Paediatric... May 2009Opsoclonus-myoclonus syndrome is a rare paraneoplastic disorder, often associated with malignancies including neuroblastoma (NB), the most common solid tumor of... (Review)
Review
Opsoclonus-myoclonus syndrome is a rare paraneoplastic disorder, often associated with malignancies including neuroblastoma (NB), the most common solid tumor of childhood derived from the sympathetic nervous system. The pathogenesis of this syndrome is still undefined but is suspected to be the result of an autoimmune response. In this respect, different autoantibodies binding to neurons or cerebellar Purkinje cells have been detected in OMS-associated NB. In addition, immunohistochemical analysis of NB affecting children with OMS demonstrated the presence of interstitial or perivascular lymphoid infiltrates resembling secondary lymphoid follicles. Immunophenotyping of these lymphoid cells showed the existence of a mesh of CD21(+) follicular dendritic cells, numerous CD20(+) B lymphocytes in the germinal center and the mantle zone of the follicle and few CD3(+) T lymphocytes in a perifollicular area. Since information is lacking about the mechanism involved in ectopic lymphoid neogenesis of OMS-associated NB, we are currently investigating the role of different chemokines and their cognate receptors in the recruitment of lymphoid cells within tumor mass of OMS-associated NB. Here, we review some recent data about the pathogenesis of OMS-associated with NB.
Topics: Autoantibodies; Chemokines; Child; Humans; Immunophenotyping; Lymphocytes; Myoclonus; Neuroblastoma; Ocular Motility Disorders; Opsoclonus-Myoclonus Syndrome
PubMed: 18571942
DOI: 10.1016/j.ejpn.2008.04.012 -
The New England Journal of Medicine Oct 1968
Topics: Electroencephalography; Humans; Infant; Male; Myoclonus; Neuroblastoma; Ocular Motility Disorders; Opsoclonus-Myoclonus Syndrome
PubMed: 20617606
DOI: 10.1056/NEJM196810242791716 -
JAMA Otolaryngology-- Head & Neck... Aug 2017
Topics: Adult; Disease Progression; Eye Movements; Female; Humans; Ocular Motility Disorders; Oculomotor Muscles; Smartphone; Videotape Recording
PubMed: 28570724
DOI: 10.1001/jamaoto.2017.0510 -
Ryoikibetsu Shokogun Shirizu 1999
Review
Topics: Cerebellar Ataxia; Diagnosis, Differential; Humans; Myoclonus; Ocular Motility Disorders; Prognosis; Syndrome
PubMed: 10434631
DOI: No ID Found