Horizontal Nystagmus Research Articles

A New Case of Mitochondrial RNA Helicase SUPV3L1-Associated Neurodegenerative Disease: Ataxia, Spasticity, Optic Atrophy, and Skin Hypopigmentation (ASOASH)

Background: The SUPV3L1 gene encodes ATP-dependent RNA helicase SUPV3L1, which is a part of the mitochondrial degradosome complex or SUV3. SUPV3L1 unwinds secondary structures of mitochondrial RNA (mtRNA) and facilitates the degradation of mtRNA molecules. A nonsense homozygous variant in the SUPV3L1 gene was recently associated with mitochondrial disease. Our study presents the second documented case of SUPV3L1 pathology in humans. Methods: Whole-genome sequencing was performed on the NovaSeq 6000 platform using pair-end reading. Data analysis was performed with an in-house developed pipeline. Results: The 17-year-old female patient exhibited a diverse array of symptoms, including ataxia, spastic paraparesis, cognitive deficit, optic atrophy, and horizontal gaze-evoked nystagmus. Early onset of symptoms, such as ataxic gait and nystagmus, was noted, with subsequent progression of neurological manifestations. At the time of the observation, the proband had extensive regions of hypopigmented skin patches on the body and extremities, which have progressed over time. Whole-genome sequencing revealed compound heterozygous variants in the SUPV3L1 gene: c.272-2A>G and c.1924A>C; p.(Ser642Arg). RNA analysis demonstrated splicing changes attributable to the c.272-2A>G variant. ELISA assay showed increased Complex I content in the patient’s fibroblasts. This case underscores the phenotypic diversity associated with SUPV3L1 mutations, emphasizing the importance of considering mitochondrial RNA helicase dysfunction in the differential diagnosis of neurodegenerative disorders. Further elucidation of the molecular mechanisms underlying SUPV3L1-associated pathology may provide valuable insights into targeted therapeutic interventions.

Clinical and Video-Oculographic Characteristics of Spinocerebellar Ataxia Type 27B (GAA-FGF14 Ataxia): A Single-Center Retrospective Study

An intronic GAA repeat expansion in the FGF14 gene was recently identified as a common cause of autosomal dominant GAA-FGF14 ataxia (SCA27B). We aimed to characterize in detail the clinical and video-oculographic features in our cohort of SCA27B patients. We genotyped the FGF14 GAA repeat expansion in 52 patients with unsolved late-onset cerebellar ataxia. Brain MRI and nerve conduction study, as well as video-oculographic (VOG) assessment, were performed. Eight patients (15.4%) with pathogenic GAA repeat expansion in the FGF14 gene were found. The median age at onset was 51 years (range—23–63 years). Sensory axonal neuropathy was found in 5/8 patients. Cerebellar atrophy was observed in 5/8 patients, and in one case, pontocerebellar atrophy was found. All tested patients had impaired smooth pursuit, 5/6 patients had impaired vestibulo-ocular reflex suppression, nystagmus, and an increased number of square wave jerks, 4/6 patients had horizontal gaze-evoked nystagmus, 3/6 had spontaneous downbeat nystagmus, and 1/6 had an upbeat one. Video head impulse test gain was lower than 0.8 on both sides in 2/4 patients, along with the presence of overt saccades. Further studies in different cohorts are needed to complete the phenotype of the FGF14-related disorders.

A Rare Case of Early Infantile Neuronal Ceroid Lipofuscinosis: Clinical and Diagnostic Insights

The Aim of the Study: The aim of this work is to show the different specific clinical and paraclinical aspects of ceroid lipofuscinosis in its early infantile form named Santavuori-Haltia disease through a new case.Given its rarety especially in consanguineous populations for better understanding the clinical presentation,progression and management of the disease. Introduction: The neuronal ceroid lipofuscinoses are a group of genetic brain diseases with an autosomal recessive manner characterized by the accumulation of an autofluorescent material in multiple tissues of patients. Clinically, they are progressive decline of mental and motor capacities, epilepsy and visual loss through retinal degeneration . In this work we report the early infantile neuronal ceroid lipofuscinosis or Santavuori-Haltia disease. Report Case: This is a 12-month-old infant from consanguineous parents who has presented with flexion spasms with eyelid clonia since the age of 1 month. The examination found microcephaly, and the neurological examination showed horizontal nystagmus with the absence of ocular pursuit and the presence of a pyramidal and extrapyramidal syndrome. Brain MRI shows delayed myelination. Skin biopsy confirms diagnosis. The Arg122Trp genetic mutation found is the most common one in this disease. Conclusion: Santaviori-Haltia disease is a rare and serious disease, the prognosis is severe, it must be mentioned in the face of psychomotor regression and a picture of encephalopathy. Confirmation of the diagnosis is based on histological and molecular biology data.

Proton pump inhibitor-induced hypomagnesemia, a rare cause of reversible delirium: A case report with literature review.

Hypomagnesemia is associated with multiple electrolyte disturbances such as hypokalemia, hypocalcemia and hypoparathyroidism. Proton pump inhibitors (PPIs) are widely used in gastrointestinal disorders and are generally considered safe by clinicians. However, it is unusual side effect of hypomagnesemia is potentially under-recognized. Delirium is usually thought to be a clue of cerebrovascular disease, and the association between delirium and hypomagnesemia is unexpected. We describe a patient used PPI with hypomagnesemia showed normal parathyroid hormone (PTH) despite hypocalcemia and reversible delirium. To enhance clinicians' vigilance, we performed a literature review on cerebellar syndromes due to hypomagnesemia. A 74-year-old woman was admitted to our hospital with intermittent nausea, vomiting, hand tremors, and delirium. Laboratory analysis showed hypokalemia, hypomagnesemia, and normal parathyroid hormone despite hypocalcemia, physical examination showed horizontal nystagmus and the brain MRI was negative. Surprising, detailed medical history revealed that the etiology was the usage of omeprazole. Omeprazole was discontinued and oral supplementation with magnesium, calcium, and potassium was administered. Delirium quickly disappeared and the serum potassium, magnesium, and calcium levels gradually normalized; at discharge, nystagmus gradually disappeared, and plasma electrolyte levels were stable at follow-up. Hypomagnesemia is associated with a variety of neurological symptoms up to life-threatening conditions if left untreated; as Mg is not present in routine electrolyte panels, hypoparathyroidism, hypokalemia, and delirium may be a clue, and physicians must be alert to consider PPI as a potential cause of unexplained hypomagnesemia, and timely treatment to avoid sequelae.

The clinical characteristics and genotype analysis of LAMB2 gene mutation.

To report a case of steroid-resistant nephrotic syndrome caused by a LAMB2 gene mutation, examine the associated literature, outline the clinical and genetic features of Pierson syndrome, and deepen the clinical comprehension of this condition. The study involved retrospective summary and analysis of the clinical presentations, genetic mutation features, and prognosis of one case involving a LAMB2 gene mutation. PubMed, Medline, Web of Science, CNKI, and Wanfang databases were searched to gather and summarize information on the pathological phenotypes and genotypic alterations associated with LAMB2 mutations. A 9-month-old infant presented with edema and massive proteinuria, along with horizontal nystagmus and miosis, manifesting clinically as steroid-resistant nephrotic syndrome. Ocular symptoms prompted both a kidney biopsy and genetic testing. The biopsy revealed minimal change disease, while genetic testing identified compound heterozygous mutations in the LAMB2 gene: c.1405C > T (p.R469X) and c.1066 T > A (p.C356S), inherited from the father and mother, respectively. These mutations were determined to be novel. The diagnosis was confirmed as a LAMB2 gene mutation. A literature review of 26 cases with LAMB2 mutations indicated these typically presented as steroid-resistant or congenital nephrotic syndrome, with 14 cases also displaying ocular symptoms. Among the 18 cases undergoing kidney biopsy, findings included focal segmental glomerulosclerosis in 10 cases, minimal change disease in 4 cases, diffuse mesangial sclerosis in 2 cases, IgM nephropathy in 1 case, and mesangial proliferation in 1 case. Electron microscopy in 10 cases showed basement membrane splitting. Genetic analysis revealed 15 cases with compound heterozygous mutations, 5 with homozygous mutations, 3 with heterozygous mutations, 2 with frame-shift mutations, and 1 with a truncating mutation. 16 out of the 26 reported cases progressed to end-stage kidney disease. Mutations in the LAMB2 gene primarily manifest as steroid-resistant or congenital nephrotic syndrome, often accompanied by ocular abnormalities, suggesting a strong likelihood of this disease. The results of genetic testing offer a foundational basis for clinical diagnosis. The identification of a new mutation site in this case expands the known spectrum of mutations in the LAMB2 gene. Unfortunately, the prognosis associated with this condition is generally poor.

Symptomatic Cerebellar Thrombosed Developmental Venous Anomaly: A Case Report

Abstract Background With the rising prevalence of advanced neuroradiological imaging, detection of incidental developmental venous anomalies (DVAs) is more commonplace. DVAs are rarely symptomatic (<2%). Typically, symptoms arise due to flow-related complications or mechanical effects. Of particular concern is venous thrombosis, a frequent flow-related complication, which can cause venous ischemia or haemorrhage. Thus, early recognition and intervention is important. Methods We describe a case of a 54-year-old male, with background of hypertension, presenting three days after sudden onset headache, ataxia, and diplopia. Initial clinical examination revealed bidirectional horizontal gaze-evoked nystagmus, skew deviation, and decreased temperature sensation of the left face. Ophthalmological examination identified left inferior rectus limitation. Results Initial non-contrast CT brain identified hypoattenuation in the right pons, suggestive of sub-acute infarction. Secondary prevention was initiated. Subsequent MRI performed 5 days later revealed hyperattenuation on T2 and FLAIR in the pons, right middle cerebellar peduncle, and right cerebellar hemisphere without restricted diffusion. SWI sequences identified an abnormal venous structure in the right cerebellum, with increased signal within it, suggestive of thrombus. The patient was diagnosed with a thrombosed DVA with associated venous oedema. Symptoms had resolved on dual antiplatelet therapy, without anticoagulation. Conclusion This case highlights the potential for DVAs, generally considered a benign entity, to become symptomatic with associated parenchymal damage and a rare, but important, stroke mimic. Moreover, it underscores the pivotal role of MRI imaging; while a CT scan might have led to the assumption of a subacute infarct, MR imaging led to a complete re-evaluation of the diagnosis in this case.

CANVAS For A Diagnosis: Can You Hear The Hooves Of Zebras?

Abstract Background A 75year old male presented to a Movement Disorder Service with complex multimorbidity including: chronic pain, type 2 diabetes mellitus, hypoventilatory obesity syndrome, biliary calculus, moderate aortic stenosis, marked orthostatic hypotension, pulmonary hypertension, coronary artery bypass grafting, permanent pacemaker for complete atrioventricular block, carpal tunnel release bilaterally, polypharmacy and bilateral cataracts. History elucidated a distal to proximal sensory loss over 20years and neuropathic pain without nerve conduction confirmation; and progressively ataxic gait over several years. He also complained of hypophonia, bruxism, excessive daytime somnolence, passages, transitions, visual agnosia, textural illusion, oscillopsia, irritability, inflexibility, hoarding, impulsivity, disorganisation, inattention, apathy, depression and aspontaneity. He was intolerant of nocturnal continuous positive airway pressure device. Epworth score was 21. Methods Examination demonstrated: marked orthostatic hypotension, preserved cognition, hypersomnolence, dyspraxic dysgraphia, palmar and antecubital agraphaesthesia, downbeat horizontal nystagmus at eccentric gaze positions, square wave jerks, bidirectionally impaired head impulse test, dysmetric saccades, asymmetric cerebellar signs in upper and lower limbs, rightward Pisa syndrome, kinesigenic dystonic axial posturing, rightward laterocollis and equivocal Babinski/Oppenheim reflexes. Gait assessment demonstrated sensory and cerebellar ataxic features with marked apraxia. No pes cavus. Results Computed tomography of brain had Fazekas 1 small vessel disease, Medial temporal atrophy score 1, Koedam 1 and age-commensurate cerebral and cerebellar atrophy. RFC1 gene testing confirmed biallelic intronic AAGGG repeat expansion disorder. Conclusion Cerebellar Ataxia Neuropathy and Vestibular Areflexia Syndrome (CANVAS) should be considered in patients with presentations from mid-life of progressive sensory ataxic neuropathy, altered vestibular ocular reflex, gaze evoked nystagmus and prominent dysautonomia. CANVAS is a rare autosomal recessive genetic disorder with a protean presentation. Referral to Genetics Services should be undertaken for family counselling. Keeping an open mind in complex, multimorbid patients to a potentially unifying diagnosis is important to guide prognostication. The rumble of hooves in the distance is not always that of horses.

Obsessive-compulsive disorder as a first manifestation of Ataxia with Oculomotor Apraxia type 2 due to a novel mutation of SETX gene.

Ataxia with oculomotor apraxia type 2 (AOA2) is an autosomal recessive disorder presenting with cerebellar ataxia, sensory-motor axonal neuropathy, oculomotor apraxia, cerebellar atrophy and high alpha-fetoprotein (AFP) serum level. AOA2 is due to coding mutations of the SETX gene, mapped to chromosome 9q34. Seldom noncoding mutations affecting RNA processing have been reported too. To date psychiatric symptoms have never been reported in AOA2. A 19 years-old man came to our attention for progressive gait ataxia debuted five years earlier. His past medical history was unremarkable, while his parents were consanguineous. On neurological examination, he had bilateral horizontal gaze-evoked nystagmus with hypometric saccades and saccadic horizontal smooth pursuit, appendicular ataxia, limbs and trunk myoclonic involuntary movements with hands' dystonic postures and dance of the tendons. Psychological evaluation described intrusive and obsessive thoughts experienced by the patient, then diagnosed as obsessive-compulsive disorder. Blood tests detected an elevated AFP level. Brain MRI showed cerebellar atrophy, while electroneuromyography revealed an axonal sensory-motor polyneuropathy. In the suspicion of a pathology belonging to the autosomal recessive cerebellar ataxias (ARCA) spectrum disorder, a direct search of point mutations by whole-exome sequencing was performed revealing a novel biallelic variant in SETX gene (c.6208+2dupT), which was classified as likely pathogenic. The present case expands the genotypic and phenotypic spectrum of AOA2, reporting a novel likely pathogenic SETX mutation (c.6208+2dupT) and highlighting an early psychiatric involvement in AOA2, suggesting the need for psychiatric assessment in these neurologic patients.

Horizontal nystagmus with velocity-increasing waveforms in delayed post-hypoxic leukoencephalopathy: a case report

Horizontal nystagmus with velocity-increasing waveforms in delayed post-hypoxic leukoencephalopathy: a case report

A acute pontine infarction with one-and-a-half syndrome as the manifestation: A case report.

Sudden ocular dyskinesia is usually associated with ophthalmic diseases and rarely with cerebrovascular diseases. This is a rare case of a patient with a sudden onset of ocular dyskinesia due to occlusion of the anterior inferior cerebellar artery and the spiral modiolar artery. This article describes eye movement disorders associated with cerebrovascular disease, aiming to improve our understanding of cerebrovascular diseases and improve the ability of early diagnosis and differential diagnosis. A 52-year-old man presented with acute pontine cerebral infarction 2 days before presentation. The main symptoms were the inability to adduct and abduct the left eyeball, the ability to abduct but not adduct the right eyeball, and horizontal nystagmus during abduction. Cranial computed tomography in our emergency department suggested cerebral infarction, and magnetic resonance imaging examination after admission confirmed the diagnosis of acute pontine cerebral infarction. This patient was ultimately diagnosed with acute pontine cerebral infarction. He received aspirin, clopidogrel, and butylphthalide, as well as acupuncture and Chinese herbal medicine. After 10 days of treatment, the patient's paralysis of the eye muscles improved significantly. Eye movement disorders are sometimes an early warning sign of impending vertebrobasilar ischemic stroke. Patients with acute ischemic stroke who have early detection of oculomotor disturbances should be promptly imaged, as missed diagnosis may lead to serious consequences or even death. It provided us with a new diagnostic idea.

MRI-confirmed cochlear artery infarct clinically diagnosed in a patient with sickle cell disease: a case report.

To corroborate the vascular etiology of sudden sensorineural hearing loss (SNHL) utilizing magnetic resonance imaging (MRI). A 24-year-old male with a history of sickle cell disease experienced sudden SNHL and right horizontal nystagmus, without accompanying vertigo. Audiometric evaluation revealed left-sided SNHL, predominantly affecting high frequencies. Video head impulse testing demonstrated isolated dysfunction of the left posterior semicircular canal. An urgent brain MRI identified a recent punctiform ischemic stroke in the frontal region. A subsequent MRI, conducted with a 4-hour delay and post-contrast enhancement, highlighted a hyperintense signal within the left cochlear region and the left posterior semicircular canal. The investigative results substantiate an infarction in the territory of the cochlear artery, precipitated by a vaso-occlusive event, thereby reinforcing the vascular hypothesis of cochleovestibular artery syndrome. This case underscores the congruence between clinical observations and delayed post-contrast MRI findings.

A case of bilateral straatsma syndrome

Straatsma syndrome is characterized by a constellation of conditions including amblyopia, nystagmus, and myopia. We present the case of a 10-year-old boy who complained of involuntary back-and-forth eye movements and reduced vision since birth. His visual acuity was measured at 2/60 in both eyes. Examination revealed horizontal pendular nystagmus without ocular misalignment. Fundus examination showed myopic changes, including an anomalous optic disc with extensive myelinated nerve fibers extending from the optic disc along the superior and inferior arcades to the fovea. Axial length measurements were 28.34 mm and 27.96 mm in the right and left eyes, respectively. SD-OCT imaging confirmed thickening of the retinal nerve fiber layer. Treatment included cycloplegic refraction and occlusion therapy, with regular follow-ups every three months utilizing contact lenses with cycloplegic refraction. The etiology of retinal fiber myelination remains unclear; however, it is hypothesized that blurred retinal imaging during critical ocular development stages may lead to axial elongation and subsequent myopia, potentially delaying the development of the lamina cribrosa and facilitating myelination extension.

A novel seated repositioning maneuver for geotropic lateral canal BPPV: efficacy and technique.

This study introduces and evaluates the sitting lateral canal maneuver (SLCM), a novel seated repositioning technique for treating geotropic lateral canal benign paroxysmal positional vertigo (BPPV). We conducted a retrospective chart review at the Hospital of Salerno, focusing on 26 patients diagnosed with geotropic LC-BPPV between 2021 and 2022. The SLCM was applied, and its efficacy was assessed based on the resolution of nystagmus and vertigo symptoms. A 95% confidence interval was calculated to estimate the success rate. The SLCM demonstrated a high success rate, with 22 out of 26 patients (approximately 85%, 22/26 patients) showing positive outcomes. The 95% confidence interval for the success rate ranged from approximately 65.02-100%. These findings suggest that SLCM is a potentially effective intervention for LC-BPPV, especially beneficial for patients who find traditional supine or lateral maneuvers uncomfortable. The SLCM represents a promising alternative to traditional BPPV maneuvers, especially for patients requiring a seated approach. While the initial results are encouraging, further research with larger sample sizes and longer follow-up periods is needed to validate its efficacy and explore its full potential in the management of LC-BPPV. This study represents a Level IV source of evidence, as defined by the evidence-based practice guidelines. It is a retrospective chart review that involves a moderate cohort of patients diagnosed with geotropic horizontal positional nystagmus consistent with lateral canal benign paroxysmal positional vertigo (LC-BPPV). While the study provides valuable insights into the efficacy of the sitting lateral canal maneuver (SLCM) and contributes to the existing literature on BPPV management, it is important to note the inherent limitations associated with this level of evidence.

Visual Fixation of Skull-Vibration-Induced Nystagmus in Patients with Peripheral Vestibulopathy.

Nystagmus induced by applying an intense vibratory stimulus to the skull (SVIN) indicates vestibular functional asymmetry. In unilateral vestibular loss, a 100 Hz bone-conducted vibration given to either mastoid immediately causes a primarily horizontal nystagmus. The test is performed in darkness to avoid visual fixation (VF) but there are no data about how much VF affects the often-intense SVIN. The aim is to analyze the amount of reduction in SVIN when VF is allowed during testing. Thus, all patients seen in a tertiary hospital for vertigo or dizziness with positive SVIN were included. SVIN was recorded for 10 s for each condition: without VF (aSVINwo) and with VF (aSVINw). We obtained an aSVINwo and an aSVINw as average slow-phase velocities (SPV) without and with VF. VF index (FISVIN) was calculated as the ratio of SPV. Among the 124 patients included, spontaneous nystagmus (SN) was found in 25% and the median slow phase velocity (mSPV) (without VF) of SN was 2.6 ± 2.4°/s. Mean FISVIN was 0.27 ± 0.29. FISVIN was 0 in 42 patients, and FISVIN between 0 and 1 was found in 82 (mean FISVIN 0.39 ± 0.02). Fixation suppression was found in all patients with SVIN in cases of peripheral vestibulopathy. FISVIN clearly delineates two populations of patients: with or without a complete visual reduction in nystagmus.

LGG-03. PREDICTIVE VALUE OF ACQUIRED NYSTAGMUS FOR PEDIATRIC BRAIN TUMOR ASSOCIATED VISUAL IMPAIRMENT: A RETROSPECTIVE STUDY

Abstract BACKGROUND Visual impairment (VI), defined as visual acuity (VA) loss or visual field (VF) defects, is common in pediatric brain tumors of the optic pathway and may impact the quality of life. VI is a challenge to establish, especially in young children. However, pediatric brain tumor patients might concurrently have acquired nystagmus (AN), which can easily be observed. The aim of this study was to investigate whether AN is predictive of VI in pediatric brain tumor patients. If correlated, AN could be an early warning sign for brain tumor related VI, warranting MRI scanning to prevent further visual deterioration, thus decreasing morbidity and mortality. METHODS Data on tumor characteristics, VA (in LogMAR), VF, (type of) AN and other ophthalmic investigations were collected from the medical records of pediatric brain tumor patients in the Máxima Pediatric Brain Tumor Ophthalmology cohort (MP-BT-O cohort). These characteristics between children with (nystagmus group) and without (control group) AN were compared to determine the predictors of VI. RESULTS The MP-BT-O cohort consists of 389 children (≤18y) with a brain tumor who had visual assessment, 95 children had AN (24.4%). The mean best corrected visual acuity (BCVA) was 0.10 LogMAR [CI 0.06-0.14] in the control and 0.50 LogMAR [CI 0.35-0.66] in the nystagmus group (p<0.001). Nystagmus type was found to be a significant predictor of VI (p<0.001). Specifically horizontal AN (a decrease in BCVA of 0.75 LogMAR, p<0.001) and mixed AN (a decrease in BCVA of 0.61 LogMAR, p<0.001) were independent predictors of VI, corrected for tumor location (p=0.04) and age at diagnosis (an increase in BCVA of -0.02 LogMAR per year, p<0.001). CONCLUSIONS Acquired nystagmus, especially horizontal and mixed nystagmus, is an independent predictor of VI in pediatric brain tumor patients and should be interpreted as a warning sign for the presence of VI.

Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease (MOGAD) Initially Presenting as Septic Meningoencephalitis in a 16-Year-Old Male.

We describe a case of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) in a 16-year-old patient who initially presented with clinical features of septic meningoencephalitis. This case outlines the importance of considering a diagnosis of MOGAD in patients who fail to improve with appropriate antimicrobial therapy or show a positive clinical response to glucocorticoids (often used in treatment of meningococcal meningitis). We emphasise the importance of recognising that an infectious prodrome can precede MOGAD. A 16-year-old male was admitted with vomiting, fever, headache, photophobia and altered mental state. He was treated for meningoencephalitis with initial clinical improvement. Lumbar puncture findings were suggestive of viral meningoencephalitis. During admission the patient went through several periods of transient clinical and biochemical improvement, alternating with periods of symptomatic relapse. On day 17 of admission, he was transferred to a tertiary centre for suspected autoimmune disseminated meningoencephalitis (ADEM) and two days later, he suffered a catastrophic neurological decline with new dysarthria, dysphagia, aphasia, horizontal nystagmus and facial paralysis. He made a remarkable neurological recovery after commencing treatment with IV immunoglobulin, IV methylprednisolone and plasma exchange, with complete resolution of symptoms. MOGAD can run a variable course and present soon after a central nervous system infection, making the diagnosis more challenging. Nonetheless, patients can achieve a full neurological recovery with early recognition, diagnosis and treatment of this rare entity. Autoimmune encephalitis can be preceded by an infectious prodrome which makes the diagnosis more challenging.Autoimmune encephalitis can run a subacute and fluctuating course with transient periods of symptomatic improvement preceding a rapid neurological decline.Glucocorticoids often used in treatment of patients with meningococcal meningitis may lead to transient symptomatic improvement in patients with autoimmune encephalitis, masking the diagnosis.MRI findings of demyelination in autoimmune encephalitis may lag behind clinical symptoms by days to weeks.

Sustained bias of spatial attention in a 3 T MRI scanner

When lying inside a MRI scanner and even in the absence of any motion, the static magnetic field of MRI scanners induces a magneto-hydrodynamic stimulation of subjects’ vestibular organ (MVS). MVS thereby not only causes a horizontal vestibular nystagmus but also induces a horizontal bias in spatial attention. In this study, we aimed to determine the time course of MVS-induced biases in both VOR and spatial attention inside a 3 T MRI-scanner as well as their respective aftereffects after participants left the scanner. Eye movements and overt spatial attention in a visual search task were assessed in healthy volunteers before, during, and after a one-hour MVS period. All participants exhibited a VOR inside the scanner, which declined over time but never vanished completely. Importantly, there was also an MVS-induced horizontal bias in spatial attention and exploration, which persisted throughout the entire hour within the scanner. Upon exiting the scanner, we observed aftereffects in the opposite direction manifested in both the VOR and in spatial attention, which were statistically no longer detectable after 7 min. Sustained MVS effects on spatial attention have important implications for the design and interpretation of fMRI-studies and for the development of therapeutic interventions counteracting spatial neglect.

The phenotypic spectrum of PTCD3 deficiency

AbstractThe PTCD3 gene product (protein PTCD3 or MRPS39) forms the entry channel of the mitochondrial small ribosomal subunit and binds to single‐stranded mRNA. Here, we expand on the clinical manifestations of PTCD3 pathogenic variants by describing an early‐onset patient with Leigh‐like syndrome and two patients with milder form of disease, with combined oxidative phosphorylation deficiency. A 34‐year‐old male and his 33‐year‐old sister both have horizontal nystagmus, pronounced rough tremor, truncal ataxia, dysmetria, spasticity and hyperreflexia. The basal respiration rate decreased significantly for the male patient and his mother (p < 0.0001) compared to the controls. The whole genome sequencing analysis revealed two heterozygous variants in the PTCD3: c.1182T>A, p.(Tyr394Ter) and c.805C>T, p.(His269Tyr). Tyr394Ter variant ablates the C‐terminal half of the protein, including a significant portion of the central fold. In silico modelling for the variant His269Tyr shows that the inclusion of the slightly larger tyrosine sidechain is well tolerated, with no significant change in either the position or the movement of the surrounding area. The third case is a 9‐year‐old boy, who has a global developmental delay, central hypotonia, hyperreflexia and abnormal MRI. PTCD3 pathogenic variant c.538+4A>G was identified by whole exome sequencing. To test the variant's effect on splicing, an RT‐PCR experiment was performed, which revealed skipping of an out‐of‐frame exon 7.

Pelizaeus disease Merzbacher like: About an observation

Pelizaeus-Merzbacher disease (PM) is an X-linked leukodystrophy causing developmental delay, nystagmus, hypotonia, spasticity and variable intellectual deficit. Three forms are described according to age of onset and severity: neonatal forms (+ severe), classical form (moderate, first 2 months of life) and transient form (the least serious 2-3 years). Prevalence is estimated at 1/400,000. We report the sighting of a 12-year-old and 8-month-old girl, with no significant history, from a non-indigenous marriage. Presents since the age of 5 months a bilateral horizontal nystagmus, myoclonia and a psychomotor retardation and whose examination revealed a pyramidal syndrome and a discreet hepatomegaly. The biological balance objectivéhyperlactatemie, hyperammoniémieet Chromatography of Amino Acids in urine showed an increase in glycine, alanine and tyrosine with Amino Acid chromatography in the blood and chromatography of Organic Acids normal. MRI brain objectified a demyelinating aspect of the white substance and atrophy of the corpus callosum. PEV pathological retina-cortical conduction, PEA altered left, Muscle biopsy absence of shredded red fibers and genetic study confirms PelizaeusMerzbacher disease like.

Visual disturbances in a 12-year-old male patient with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes syndrome

Abstract: Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a rare condition. Here, we present a case of a male patient with a very unique combination of symptoms that started at the age of 12. Transient symptoms manifested after 4 days of high fever and included lethargy, a loss of appetite, and an inability to recognize faces. After that, the patient was symptom-free for 4 years before he was hospitalized again with a working diagnosis of acute disseminated encephalomyelitis. The ophthalmic symptoms at this stage were photophobia and discrete horizontal nystagmus. One year later, the patient had another seizure and during hospitalization, predominantly displayed cerebral symptoms such as dystaxia, dysmetria, generalized muscle hypotrophy, and absent myotonic reflexes. Like before, an ophthalmic examination demonstrated a best-corrected visual acuity of 1.0 and a normal anterior segment. A fundus examination revealed a slightly rarefied retina, along with areas of perifoveal and parapapillary atrophy, in addition to increased vascular tortuosity. Optical coherence tomography scans of the macula and the optic disc depicted a mild thinning of the retinal layers. Visual field testing showed an isopter contraction with a predominant loss of the temporal visual field in both eyes. A genetic serum analysis was positive for mitochondrial mutation m.3243A>G, and a diagnosis of MELAS was confirmed. The treatment included anticonvulsive drugs and dietary precautions. Patients with MELAS syndrome can manifest a wide range of visual disturbances, meaning that a detailed ophthalmic examination is required.