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Biallelic pathogenic variants in theANO10gene cause spinocerebellar ataxia recessive type 10. We report two patients, both compound heterozygous forANO10variants, including two novel variants. Both patients had onset of cerebellar ataxia in adulthood with slow progression and presented corticospinal tract signs, eye movement abnormalities and cognitive executive impairment. One of them had temporal lobe epilepsy and she also carried a heterozygous variant inCACNB4, a potential risk gene for epilepsy. Both patients had pronounced cerebellar atrophy on cerebral magnetic resonance imaging (MRI) and reduced metabolic activity in cerebellum as well as in the frontal lobes on 2-deoxy-2-(18F)fluoro-D-glucose positron emission tomography ((18F)FDG PET) scans. We provide comprehensive clinical, radiological and genetic data on two patients carrying likely pathogenicANO10gene variants. Furthermore, we provide evidence for a cerebellar as well as a frontal involvement on brain (18F)FDG PET scans which has not previously been reported.

Cerebellar ataxia results from damage to the cerebellum and presents as movement incoordination and variability, gait impairment, and slurred speech. Patients with cerebellar ataxia can also have cognitive and mood changes. Although the identification of causes for cerebellar ataxia can be complex, age of presentation, chronicity, family history, and associated movement disorders may provide diagnostic clues. There are many genetic causes for cerebellar ataxia, and the common autosomal dominant and recessive ataxia are due to genetic repeat expansions. Step-by-step approach will lead to the identification of the causes. Symptomatic and potential disease-modifying therapies may benefit patients with cerebellar ataxia.

A 64-year-old man presented with a 6-month history of lightheadedness and intermittent balance and coordination difficulties. Two months before admission, symptoms became more substantial and persistent, with a worsening sense of disequilibrium and unsteady gait. He reported difficulties pronouncing words and mild word-finding difficulties. His wife noted a change in his cognition and memory over the same time. His medical history included well-controlled chronic obstructive pulmonary disease (COPD) secondary to a long history of smoking with associated unintentional 30-lb (13.6-kg) weight loss over the previous 3 years, for which chest CT scanning was performed, revealing no abnormality. On clinical examination, the patient was alert and oriented but had slurred speech. A positive Romberg sign was noted, finger-to-nose and hand rapid alternating movement tests revealed impairment on the right side, and his gait was ataxic. The motor examination revealed normal muscle tone, bulk, and power in the upper and lower extremities. Sensory testing results were normal. Initial MRI of the brain at admission revealed abnormal findings in the left supratentorial brain. Of note, this patient's presentation predated the COVID-19 pandemic. Cerebrospinal fluid (CSF) analysis revealed predominant pleocytosis (23 × 106/L; normal range, [0-5] × 106/L) (78% lymphocytes, 22% monocytes), elevated protein level (1.23 g/L; normal range, 0.19-0.64 g/L), oligoclonal bands (faint one or two), and a high immunoglobulin G (IgG) index (0.130 g/L; normal reference, ≤0.059 g/L). Despite extensive initial work-up for inflammatory, infectious, autoimmune, or neoplastic causes, a definitive diagnosis was not reached. Thus, repeat MRI of the brain was performed 2 weeks after admission.

Sporadic, adult-onset cerebellar ataxia is a disease with multiple etiologies. In addition to cortical cerebellar atrophy (CCA), which is often used for the pathological diagnosis, other terms such as idiopathic late-onset cerebellar ataxia (ILOCA) and sporadic adult-onset ataxia of unknown etiology (SAOA) have been used to refer to this disorder. These names describe key features of the disease, including degeneration limited to the cerebellar cortex (with or without secondary involvement of inferior olivary nuclei), a slowly progressive ataxia, and absence of a clear etiology, such as multiple system atrophy, as well as paraneoplastic, autoimmune, infectious and inherited ataxias. In this Point of View article, we describe two patients with sporadic, adult-onset ataxia with rapidly progressive disease course in addition to extracerebellar symptoms resembling prion disease, including the reevaluation of one patient who was previously reported. Pathological findings are mostly consistent with CCA, but also have degenerative changes in the thalamus. Whole genome sequencing in two patients with rapidly progressive CCA did not reveal any pathogenic variants associated with cerebellar ataxia. Although the underlying etiology behind rapidly progressive CCA is unknown, we suggest that the unique combination of clinical and pathological features of CAA with a short disease course defines a new disease entity, rapidly progressive cerebellar cortical and thalamic degeneration. This viewpoint article draws attention to this rare sporadic cerebellar ataxia with the hope that highlighting clinical and pathologic findings in a typical case will lead to improved recognition and research.

The biallelic pathogenic repeat (AAGGG)

VPS13D is a recently described gene. Worldwide, only 15 families with 23 affected individuals have been reported with a VPS13D-based disease. Mutated VPS13D causes a complex phenotype with a hyperkinetic movement disorder and ataxia, especially in childhood onset disease. The clinical phenotype of the rare adult-onset cases consists of cerebellar ataxia and/or spastic paraplegia. Here, we report the extensive clinical, laboratory and genetic findings of two offspring from consanguineous parents, with ages of disease onset at 57 and 49 with VPS13D-based ataxia. Although conventional magnetic resonance imaging showed mild cerebellar and cerebral atrophy, diffusion tensor imaging, applied for the first time for VPS13D patients, revealed prominent atrophy in U fibers and cerebellopontine tracts. Whole exome sequencing analysis revealed a biallelic Ala4210Val mutation in the VPS13D, reported only once in the literature. Complementary screening of our in-house database consisting of 295 ataxia and hereditary spastic paraplegia patients revealed two further ataxia patients with novel VPS13D variants. Screening the control cohort for VPS13D variants revealed one asymptomatic individual carrying a novel VPS13D variant. In this study, the phenotypic spectrum of VPS13D-based disease is expanded with the description of pre-senile onset predominant ataxia. Further, with the additional novel mutations described, the report is expected to contribute to the understanding of the yet elusive phenotype-genotype correlations in the rare VPS13D-based movement disorder.

OBJECTIVE: To evaluate the benefit of vestibular rehabilitation therapy (VRT) in the management of patients with idiopathic cerebellar ataxia with bilateral vestibulopathy (iCABV). BACKGROUND: iCABV is a hindbrain degenerative disorder with impairment of both central and peripheral vestibular pathways. There is combined failure of four compensatory eye movement systems including the vestibulo-ocular reflex (VOR), optokinetic reflex, smooth pursuit and the visually enhanced vestibulo-ocular reflex (VVOR). Phenotypic presentation includes postural and gait instability, oscillopsia and dizziness with active head movement. The benefit of VRT in iCABV patients has not been established. METHODS: A retrospective review was performed on a cohort of twelve patients diagnosed with iCABV in a multidisciplinary neuro-otology clinic. All participated in VRT and completed their suggested course of VRT. The following clinical measures were assessed before starting and after finishing VRT: 1) Dizziness Handicap Inventory (DHI), 2) Activities-Specific Balance Confidence (ABC) Scale, 3) Catastrophization scale, 4) Positive Affective Negative Affective Score (PANAS), 5) Dynamic Gait Index (DGI) and 6) Modified Clinical Test of Sensory Interaction in Balance (mCTSIB). The number of falls historically was recorded in addition to gait speed (ft./sec). RESULTS: Following VRT, patients were found to have improved balance on mCTSIB (condition 4 : 7 vs 18 seconds, P = 0.04) and a better postural stability with a reduced number of falls (p = 0.01). No statistically significant improvement was seen in the DHI, ABC, Catastrophization scale, DGI, PANAS and gait speed (p > 0.05). CONCLUSIONS: iCABV patients who underwent VRT were found to have a better postural stability and reduced risk of falls. VRT was not found to significantly improve patients’ overall subjective perception of their symptoms or their psychological status.

Introduction: In young children with early onset ataxia (EOA), quantitative rating of ataxia by the Scale for Assessment and Rating of Ataxia (SARA) is longitudinally influenced by the physiological age effect on motor coordination. To enable longitudinal quantitative interpretation of ataxia by SARA in children with EOA, the EPNS ataxia working group has previously determined SARA-scores in typically developing children (4-16 years of age). In toddlers, this information is still lacking. We therefore aimed to investigate the feasibility and reliability of SARA-scores in typically developing toddlers. Methods: In 57 typically developing toddlers (2-4 years), we aimed to determine the: 1. feasibility of SARA -scores, 2. age-related pre-requisites to obtain SARA-scores in toddlers over all domains, 3. SARA-score reliability, 4. mathematical age connection of SARA-scores in toddlers and older children. Results: In typically developing toddlers, the feasibility of SARA is strongly age-dependent (p < .000). After computing compensations for two age-related, unfeasible and therefore un-assessable kinetic subtasks and after allowing the videotaping of non-kinetic SARA sub-task performances at home, the SARA was fully reliably assessable in all (n = 57) toddlers (ICC = 0.732). From two to 16 years of age, SARA-scores were mathematically represented by one continuous, exponentially decreasing trend line approaching the adult-optimum at 16 years of age. Conclusion: In toddlers, SARA-scores are reliably assessable, by using two age-compensations and allowing the videotaping of SARA-performances partly at home. In children with EOA, these data enable longitudinal quantification and interpretation of quantitative ataxia-scores by SARA from 2 years of age throughout childhood.

The link between paraneoplastic neurological syndromes (PNS) and renal cell and bladder cancer (RCC/BC) is rare and uncertain. Our aim was to clinically evaluate, in light of the updated PNS criteria, these uncommon associations.Retrospective nationwide cohort chart review study and systematic review of the literature.After excluding 5 patients due to the diagnosis of another co-occurrent malignancy, 10/18 patients with RCC and 8/18 patients with BC were identified. A total of 31 cases were previously published, yielding an overall series of 27/49 RCC and 22/49 BC patients. There was a predominance of cerebellar syndromes in both cancers (10/27, 37% for RCC; 9/22, 41% for BC), followed by encephalitis in 9/27 (33%) patients with RCC and encephalomyelitis/sensory neuronopathy in 5/22 (23%) patients with BC. The detection of high-risk Abs was more frequent among BC patients (16/19, 84% vs. 3/13, 23% in RCC, p = 0.0009), Ri antibodies being the most frequent thereof. After applying the updated PNS criteria, patients with BC met highest degrees (possible, probable, and definite) of certainty for PNS diagnosis (20/22, 91% vs. 16/27, 59% in RCC, p = 0.021).A second neoplasm should always be ruled out before establishing the diagnosis of PNS in patients with RCC or BC. However, while this association remains dubious for most patients with RCC, a casual role is more probable in patients with BC and high-risk antibodies presenting with cerebellar ataxia, brainstem encephalitis or encephalomyelitis/sensory neuronopathy.

Various disorders can cause acute onset ataxia including those that have toxic/metabolic, traumatic, neoplastic, vascular, demyelinating/dysmyelinating, infectious, postinfectious and genetic features. We present a case of postseptic acute ataxia. A 72-year-old woman was diagnosed with septic shock secondary to acute obstructive suppurative cholangitis. A blood sample for bacterial culture was positive for

Assessment of motor severity in cerebellar ataxia is critical for monitoring disease progression and evaluating the effectiveness of therapeutic interventions. Though wearable sensors have been used to monitor gait tasks in order to enable frequent assessment, existing solutions only estimate gait performance severity rather than comprehensive motor severity. In this study, we propose a new approach that analyzes sub-second movement profiles of the lower-limbs during gait to estimate overall motor severity in cerebellar ataxia.A total of 37 ataxia subjects and 12 healthy subjects performed a 5 m walk-and-turn task with two ankle-worn inertial sensors. Lower-limb movements were decomposed into one-dimensional sub-movements, namely movement elements. Supervised regression models trained on data features of movement elements estimated the Brief Ataxia Rating Scale (BARS) and its sub-scores evaluated by clinicians. The proposed models were also compared to models trained on widely-accepted spatiotemporal gait features.Estimated total BARS showed strong agreement with clinician-evaluated scores with rThe proposed algorithm accurately assessed overall motor severity in cerebellar ataxia using inertial data collected from bilaterally-placed ankle sensors during a simple walk-and-turn task.Our work could support fine-grained monitoring of disease progression and patients' responses to medical/clinical interventions.

Ataxia is one of the most common pediatric movement disorders and can be caused by a large number of congenital and acquired diseases affecting the cerebellum or the vestibular or sensory system. It is mainly characterized by gait abnormalities, dysmetria, intention tremor, dysdiadochokinesia, dysarthria, and nystagmus. In young children, ataxia may manifest as the inability or refusal to walk. The diagnostic approach begins with a careful clinical history including the temporal evolution of ataxia and the inquiry of additional symptoms, is followed by a meticulous physical examination, and, depending on the results, is complemented by laboratory assays, electroencephalography, nerve conduction velocity, lumbar puncture, toxicology screening, genetic testing, and neuroimaging. Neuroimaging plays a pivotal role in either providing the final diagnosis, narrowing the differential diagnosis, or planning targeted further workup. In this review, we will focus on the most common form of ataxia in childhood, cerebellar ataxia (CA). We will discuss and summarize the neuroimaging findings of either the most common or the most important causes of CA in childhood or present causes of pediatric CA with pathognomonic findings on MRI. The various pediatric CAs will be categorized and presented according to (a) the cause of ataxia (acquired/disruptive vs. inherited/genetic) and (b) the temporal evolution of symptoms (acute/subacute, chronic, progressive, nonprogressive, and recurrent). In addition, several illustrative cases with their key imaging findings will be presented.

Dengue fever has been associated with several neurological complications, cerebellar involvement being among the rarest of them. Here, we describe the case of a 70-year-old female who presented a cerebellar syndrome during the first day of an arboviral infection, posteriorly confirmed as dengue fever. Among the seven other cases in which the relationship between dengue virus and ataxia was reported, only in one cerebellar presentation occurred as early. Onset, course, and prognosis, as well as the adequate investigation and management of these patients, are discussed. While the disease pattern is not better characterized by future studies, differential diagnosis and close follow-up are essential tools for guaranteeing good outcomes.

Primary coenzyme Q10 (CoQ10) deficiency, a recessive disorder associated with various defects of CoQ10 biosynthesis and widely varying clinical presentation, is customarily managed by oral Q10 supplementation but the benefit is debated.To address this question, we mapped individual responses in two patients with COQ8A-related ataxia following coenzyme Q10 supplementation using noninvasive imaging. MetabolicPost-treatment change in energy metabolite levels differed in the two patients, with higher energy levels and improved dysarthria and leg coordination in one, and decreased energy levels without clinical benefit in the other.Our results suggest that the cerebellar bioenergetic state may predict treatment response in COQ8A-related ataxia and highlight the potential of pathophysiology-orientated neuroimaging evidence to inform treatment decisions.

Ataxia-Telangiectasia (A-T) is an autosomal recessive neurodegenerative disease associated with cerebellar ataxia and extrapyramidal features. A-T has a complex and diverse phenotype with varying rates of disease progression. The development of robust natural history studies and therapeutic trials relies on the accurate recording of phenotype using relevant and validated severity of illness indexes. We compared the commonly used Scale for the Assessment and Rating of Ataxia (SARA) and the disease-specific A-T Neurological Examination Scale Toolkit (A-T NEST), in our adult A-T cohort. We found a strong correlation between A-T NEST and the established SARA score, validating the use of A-T NEST and SARA in capturing the natural history of A-T patients.

This 18-year-old boy presented to the hospital with symptoms of cerebellar dysfunction preceded by an acute febrile illness with rash. Examination showed evidence of left-sided cerebellar dysfunction and polyneuropathy. Empirical treatment for leptospirosis and scrub typhus was initiated. MRI was normal. Other organ dysfunctions in the form of thrombocytopenia and transaminitis were also observed. He recovered without sequelae. A diagnosis of acute cerebellar ataxia and polyneuropathy due to scrub typhus was made.

Data de publicació electrònica: 04-03-2023 The Ataxia Global Initiative (AGI) is a worldwide multi-stakeholder research platform to systematically enhance trial-readiness in degenerative ataxias. The next-generation sequencing (NGS) working group of the AGI aims to improve methods, platforms, and international standards for ataxia NGS analysis and data sharing, ultimately allowing to increase the number of genetically ataxia patients amenable for natural history and treatment trials. Despite extensive implementation of NGS for ataxia patients in clinical and research settings, the diagnostic gap remains sizeable, as approximately 50% of patients with hereditary ataxia remain genetically undiagnosed. One current shortcoming is the fragmentation of patients and NGS datasets on different analysis platforms and databases around the world. The AGI NGS working group in collaboration with the AGI associated research platforms—CAGC, GENESIS, and RD-Connect GPAP—provides clinicians and scientists access to user-friendly and adaptable interfaces to analyze genome-scale patient data. These platforms also foster collaboration within the ataxia community. These efforts and tools have led to the diagnosis of > 500 ataxia patients and the discovery of > 30 novel ataxia genes. Here, the AGI NGS working group presents their consensus recommendations for NGS data sharing initiatives in the ataxia field, focusing on harmonized NGS variant analysis and standardized clinical and metadata collection, combined with collaborative data and analysis tool sharing across platforms. Open Access funding enabled and organized by Projekt DEAL. This work was supported by the Horizon 2020 research and innovation programme (grant 779257 Solve-RD to MS and SB), and the European Joint Programme on Rare Diseases (grant 825575 EJP RD to SB) under the EJP RD COFUND-EJP No. 825575 (PROSPAX consortium, to MS and—as an associated partner—SZ). DB is supported by a Postdoctoral Fellowship from the Alexander von Humboldt Foundation.

Autosomal recessive spinocerebellar ataxia type 8 (ARCA1/SCAR8) is caused by mutations of the SYNE1 gene. The disease was initially described in families from Quebec (Canada) with a phenotype of pure cerebellar syndrome, but in recent years has been reported with a more variable clinical phenotype in other countries. Cases have recently been described of muscular dystrophy, arthrogryposis, and cardiomyopathy due to SYNE1 mutations. To describe clinical and molecular findings from 4 patients (3 men and one woman) diagnosed with ARCA1/SCAR8 from 3 Spanish families from different regions. We describe the clinical, paraclinical, and genetic results from 4 patients diagnosed with ARCA1/SCAR8 at different Spanish neurology departments. Onset occurred in the third or fourth decade of live in all patients. After 15 years of progression, 3 patients presented pure cerebellar syndrome, similar to the Canadian patients; the fourth patient, with over 30 years' progression, presented vertical gaze palsy, pyramidal signs, and moderate cognitive impairment. In all patients, MRI studies showed cerebellar atrophy. The genetic study revealed distinct pathogenic SYNE1 mutations in each family. ARCA1/SCAR8 can be found worldwide and may be caused by many distinct mutations in the SYNE1 gene. The disease may manifest with a complex phenotype of varying severity.

Parkinsonian diseases and cerebellar ataxia among movement disorders, are representative diseases which present with distinct pathological gaits. We proposed a machine learning system that can differentiate Parkinson's disease (PD), cerebellar ataxia and progressive supranuclear palsy Richardson syndrome (PSP-RS) based on postural instability and gait analysis.We screened 1467 gait (GAITRite) and postural instability (Pedoscan) analyses performed in Samsung Medical Center from January 2019 to December 2020. PD, probable PSP-RS, and cerebellar ataxia (i.e., probable MSA-C, hereditary ataxia, and sporadic adult-onset ataxia) were included in the study. The gated recurrent units for GaitRite and the deep neural network for Pedoscan were applied. The enhanced weight voting ensemble (EWVE) method was applied to incorporate the two modalities.We included 551 PD, 38 PSP-RS, 113 cerebellar ataxia and among them, 71 were MSA-C. Pedoscan-based and Gait-based model showed high sensitivity but low specificity in differentiating atypical parkinsonism from PD. The EWVE showed significantly improved specificity and reliable performance in differentiation between PD vs. ataxia patients (AUC 0.974 ± 0.036, sensitivity 0.829 ± 0.217, specificity 0.969 ± 0.038), PD vs. MSA-C (AUC 0.975 ± 0.020, sensitivity 0.823 ± 0.162, specificity 0.932 ± 0.030) and PD vs. PSP-RS (AUC 0.963 ± 0.028, sensitivity 0.555 ± 0.157, specificity 0.936 ± 0.031).We proposed reliable Pedoscan-based, Gait-based and EWVE model in differentiating gait disorders by integrating information from gait and postural instability. This model can provide diagnosis guidelines to primary caregivers and assist in differential diagnosis of PD from atypical parkinsonism for neurologists.

Impaired cerebellar Purkinje neuron firing resulting from reduced expression of large-conductance calcium-activated potassium (BK) channels is a consistent feature in models of inherited neurodegenerative spinocerebellar ataxia (SCA). Restoring BK channel expression improves motor function and delays cerebellar degeneration, indicating that BK channels are an attractive therapeutic target. Current BK channel activators lack specificity and potency and are therefore poor templates for future drug development. We implemented an automated patch clamp platform for high-throughput drug discovery of BK channel activators using the Nanion SyncroPatch 384PE system. We screened over 15,000 compounds for their ability to increase BK channel current amplitude under conditions of lower intracellular calcium that is present in disease. We identified several novel BK channel activators that were then retested on the SyncroPatch 384PE to generate concentration-response curves (CRCs). Compounds with favorable CRCs were subsequently tested for their ability to improve irregular cerebellar Purkinje neuron spiking, characteristic of BK channel dysfunction in SCA1 mice. We identified a novel BK channel activator, 4-chloro-N-(5-chloro-2-cyanophenyl)-3-(trifluoromethyl)benzene-1-sulfonamide (herein renamed BK-20), that exhibited a more potent half-maximal activation of BK current (pAC50 = 4.64) than NS-1619 (pAC50 = 3.7) at a free internal calcium concentration of 270 nM in a heterologous expression system and improved spiking regularity in SCA1 Purkinje neurons. BK-20 had no activity on small-conductance calcium-activated potassium (SK)1–3 channels but interestingly was a potent blocker of the T-type calcium channel, Cav3.1 (IC(50) = 1.05 μM). Our work describes both a novel compound for further drug development in disorders with irregular Purkinje spiking and a unique platform for drug discovery in degenerative ataxias. SIGNIFICANCE STATEMENT: Motor impairment associated with altered Purkinje cell spiking due to dysregulation of large-conductance calcium-activated potassium (BK) channel expression and function is a shared feature of disease in many degenerative ataxias. BK channel activators represent an outstanding therapeutic agent for ataxia. We have developed a high-throughput platform to screen for BK channel activators and identified a novel compound that can serve as a template for future drug development for the treatment of these disabling disorders.

The antiseizure medication phenytoin has been associated with changes in the cerebellum, cerebellar signs, and permanent cerebellar damage. We have systematically reviewed the clinical and radiological features, and their correlation.We identified sixty case reports and case series of the effects of phenytoin on the cerebellum by searching Medline and Embase and relevant reference lists. The reports described 92 [median 1, range 1-5] cases, documented median age 28 [2.7-78] years. Eighty-one cases described one or more clinical sign of ataxia (present in 96%), dysarthria (63%), and nystagmus (70%). The neurological outcome (in 76 cases): 10 (13%) recovered by 12 months; 55 (72%) suffered residual disability; and 11 (14%) died. Median serum phenytoin concentration (48 cases) was 50 (interquartile range 31-66) mg/L; only three values were below 20 mg/L. The radiological findings included cerebellar atrophy in 41 of 61 patients (67%) with at least one scan.Evidence mainly comes from case reports, and is inevitably biased. Most patients with cerebellar dysfunction have phenytoin concentrations above the reference range. Clinical signs of ataxia can persist without radiological evidence of cerebellar atrophy, and cerebellar atrophy is seen without any clinical evidence of cerebellar dysfunction.

Background and ObjectivesIndividuals with cerebellar ataxia (CA) can develop impulsive behavioral symptoms, often resulting in negative interpersonal consequences, detrimentally affecting their quality of life. Limited evidence exists concerning impulsivity in CA and its associated behavioral changes. We assessed impulsive traits in CA using the Barratt Impulsivity Scale (BIS-11) and compared them with those of Parkinson disease (PD) to investigate the differences in the impulsive trait profiles between CA and PD.MethodsWe conducted a dual-center cross-sectional study with individuals with CA and PD enrolled through consecutive sampling from movement disorders clinics at Columbia University Medical Center and Vanderbilt University Medical Center, respectively. Age-matched controls were recruited at the respective institutions. Participants were excluded if they had prior or comorbid neurologic and psychiatric diseases known to be associated with impulsivity. All participants completed the BIS-11 questionnaire as a measure of impulsive traits. We used a general linear model and a least absolute shrinkage and selection operation regression to compare the total, subscale, and individual items of the BIS-11 scores between groups. Subgroup analyses were performed to isolate cerebellar contributions to impulsivity from potential effects of extracerebellar pathology and dopaminergic dysfunction or medications.ResultsA total of 190 participants—90 age-matched controls, 50 participants with CA, and 50 with PD—completed the assessments. Persons with CA reported 9.7% higher BIS-11 scores than controls (p < 0.001), while persons with PD reported 24.9% higher scores than controls (p < 0.001). In CA, the most affected domain of impulsivity was nonplanning. In contrast, persons with PD noted greater impulsivity across the nonplanning, attentional, and motor domains.DiscussionImpulsivity in CA is uniquely driven by the nonplanning trait, unlike in PD. This suggests that the cerebellum and basal ganglia may differentially govern impulsive behaviors with the cerebellum contributing to the brain circuitry of impulsivity in a domain-specific manner.

Hereditary ataxias are a group of devastating neurological disorders that affect coordination of gait and are often associated with poor coordination of hands, speech, and eye movements. Ataxia with Ocular Apraxia type 1 (AOA1) (OMIM: 606350.0006) is characterized by slowly progressive symptoms of childhood-onset and pathogenic mutations in APTX; the only known cause underpinning AOA1. APTX encodes the protein Aprataxin, composed of three domains sharing homology with proteins involved in DNA damage, signaling, and repair. We present four siblings from an endogamic family in a rural, isolated town of Colombia with ataxia and ocular apraxia of childhood-onset and confirmed molecular diagnosis of AOA1, homozygous for the W279* p.Trp279Ter mutation. We predicted the mutated APTX with Alpha Fold to demonstrate the effects of this stop-gain mutation that deletes three beta helices encoded by amino acid 270 to 339 rescinding the C2H2-type zinc fingers (Znf) (C2H2 Znf) DNA-binding and DNA-repair domain and the whole tridimensional structure of the APTX. All siblings exhibited different ages of onset (4, 6, 8, and 11 y/o) and heterogeneous patterns of dysarthria (ranging from absence to mild-moderate dysarthria). Neuropsychological evaluation showed no neurocognitive impairment in three siblings, but one sibling showed temporospatial disorientation, semantic and phonologic fluency impairment, episodic memory affection, constructional apraxia, moderate anomia, low executive function, and symptoms of depression. This heterogeneous phenotype suggests genetic interactions can shape the natural history of AOA1. To our knowledge, this report represents the most extensive series of siblings affected with AOA1 in Latin America, and the genetic analysis completed adds important knowledge to outline this family’s disease and general complex phenotype of hereditary ataxias.

The aim of this consensus paper is to discuss the roles of the cerebellum in human gait, as well as its assessment and therapy. Cerebellar vermis is critical for postural control. The cerebellum ensures the mapping of sensory information into temporally relevant motor commands. Mental imagery of gait involves intrinsically connected fronto-parietal networks comprising the cerebellum. Muscular activities in cerebellar patients show impaired timing of discharges, affecting the patterning of the synergies subserving locomotion. Ataxia of stance/gait is amongst the first cerebellar deficits in cerebellar disorders such as degenerative ataxias and is a disabling symptom with a high risk of falls. Prolonged discharges and increased muscle coactivation may be related to compensatory mechanisms and enhanced body sway, respectively. Essential tremor is frequently associated with mild gait ataxia. There is growing evidence for an important role of the cerebellar cortex in the pathogenesis of essential tremor. In multiple sclerosis, balance and gait are affected due to cerebellar and spinal cord involvement, as a result of disseminated demyelination and neurodegeneration impairing proprioception. In orthostatic tremor, patients often show mild-to-moderate limb and gait ataxia. The tremor generator is likely located in the posterior fossa. Tandem gait is impaired in the early stages of cerebellar disorders and may be particularly useful in the evaluation of pre-ataxic stages of progressive ataxias. Impaired inter-joint coordination and enhanced variability of gait temporal and kinetic parameters can be grasped by wearable devices such as accelerometers. Kinect is a promising low cost technology to obtain reliable measurements and remote assessments of gait. Deep learning methods are being developed in order to help clinicians in the diagnosis and decision-making process. Locomotor adaptation is impaired in cerebellar patients. Coordinative training aims to improve the coordinative strategy and foot placements across strides, cerebellar patients benefiting from intense rehabilitation therapies. Robotic training is a promising approach to complement conventional rehabilitation and neuromodulation of the cerebellum. Wearable dynamic orthoses represent a potential aid to assist gait. The panel of experts agree that the understanding of the cerebellar contribution to gait control will lead to a better management of cerebellar ataxias in general and will likely contribute to use gait parameters as robust biomarkers of future clinical trials.

INTRODUCTION: Up to 34% of patients with medulloblastoma develop posterior fossa syndrome (PFS) following brain tumor resection and have increased risk of long-term neurocognitive impairments. Lack of agreement in conceptualization and diagnosis of PFS calls for improvements in diagnostic methods. The current study aimed to describe psychometric properties of a new Posterior Fossa Syndrome Questionnaire (PFSQ). METHODS: The PFSQ was informed by prior research and developed by a multidisciplinary team with subject matter expertise. Participants (N = 164; 63.4% Male; 78.7% White; M(age at diagnosis) = 10.38 years, SD = 5.09, range 3 – 31 years) included patients with newly diagnosed medulloblastoma enrolled in the SJMB12 clinical trial. Forty-four patients (26.8%) were classified as having PFS based on attending physician’s post-surgical yes/no report. A PFSQ was completed by a neurologist within 2 weeks of coming to St. Jude Children’s Research Hospital for adjuvant treatment, irrespective of suspicion for PFS. RESULTS: PFSQ items Ataxia (100.00%), Dysmetria (95.45%), and Speech/Language Changes (79.55%) were most sensitive. However, Ataxia (26.50%) and Dysmetria (46.61%) demonstrated low specificity. Speech/Language Changes (81.36%), Mutism (95.76%), Orofacial Apraxia (98.29%) and Irritability (96.61%) had high specificity. A principal component analysis found four components: 1) Speech/Language Changes, 2) Apraxias (including mutism), 3) Motor/Oromotor, and 4) Emotional Lability. CONCLUSIONS: The PFSQ is a dimensional diagnostic approach that can be used to improve diagnostic consistency across clinical and research groups to help accelerate understanding of PFS etiology, identify surgical correlates of risk, predict long-term impairments, and develop targeted interventions. Additional measure validation, including correlation with symptom resolution, is required.

We propose an approach for the identification of mutant genes for rare diseases in single cases of unknown etiology. All genes with rare biologically significant variants sorted from individual exome data are tested further for profiling of their spatial-temporal and cell/tissue specific expression compared to that of their paralogs. We developed a simple bioinformatics tool (“Essential Paralogue by Expression” (EPbE)) for such analysis. Here, we present rare clinical forms of early ataxia with cerebellar hypoplasia. Using whole-exome sequencing and the EPbE tool, we identified two novel mutant genes previously not associated with congenital human diseases. In Family I, the unique missense mutation (p.Lys258Glu) was found in the LRCH2 gene inherited in an X-linked manner. p.Lys258Glu occurs in the evolutionarily invariant site of the leucine-rich repeat domain of LRCH2. In Family II and Family III, the identical genetic variant was found in the CSMD1 gene inherited as an autosomal-recessive trait. The variant leads to amino acid substitution p.Gly2979Ser in a highly conserved region of the complement-interacting domain of CSMD1. The LRCH2 gene for Family I patients (in which congenital cerebellar hypoplasia was associated with demyelinating polyneuropathy) is expressed in Schwann and precursor Schwann cells and predominantly over its paralogous genes in the developing cerebellar cortex. The CSMD1 gene is predominantly expressed over its paralogous genes in the cerebellum, specifically in the period of late childhood. Thus, the comparative spatial-temporal expression of the selected genes corresponds to the neurological manifestations of the disease.

Cerebellar and afferent ataxias present with a characteristic gait disorder that reflects cerebellar motor dysfunction and sensory loss. These disorders are a diagnostic challenge for clinicians because of the large number of acquired and inherited diseases that cause cerebellar and sensory neuron damage. Among such conditions that are recessively inherited, Friedreich ataxia and RFC1-associated cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS) include the characteristic clinical, neuropathological and imaging features of ganglionopathies, a distinctive non-length-dependent type of sensory involvement. In this Review, we discuss the typical and atypical phenotypes of Friedreich ataxia and CANVAS, along with the features of other recessive ataxias that present with a ganglionopathy or polyneuropathy, with an emphasis on recently described clinical features, natural history and genotype-phenotype correlations. We review the main developments in understanding the complex pathology that affects the sensory neurons and cerebellum, which seem to be most vulnerable to disorders that affect mitochondrial function and DNA repair mechanisms. Finally, we discuss disease-modifying therapeutic advances in Friedreich ataxia, highlighting the most promising candidate molecules and lessons learned from previous clinical trials.

To quantitatively evaluate upper limb ataxia using a novel pen-like sensor device in patients with spinocerebellar ataxia (SCA) and to assess its validity, reliability, and sensitivity to disease progression.We designed a cross-sectional and longitudinal study of patients with SCA and healthy controls. Upper limb ataxia was evaluated using a device that measures the three-dimensional position every 10 msec. Participants were instructed to move a pen-like part of the device iteratively between two buttons. We evaluated the time, length, velocity, and variation coefficient of the stroke, and calculated the distortion index using the mean squared error. The following scales were also evaluated: Scale for the Assessment and Rating of Ataxia (SARA), the International Cooperative Ataxia Rating Scale (ICARS), and the nine-hole pegboard test. Subjects were followed 12 months after the baseline evaluation.A total of 42 patients with SCA and 33 healthy controls were enrolled and evaluated. For all ataxia indices measured using the device there were significant differences between healthy controls and patients with SCA. Among the ataxia indices, the distortion index showed the strongest correlation with the SARA and ICARS upper limb score (Pearson's r = 0.647 and 0.722, respectively). Test-retest reliability was high for most of the ataxia indices. In the longitudinal analysis, the distortion index showed high standardized response mean and adjusted effect size, regardless of disease severity.Our study demonstrated that the distortion index is a reliable functional marker that is sensitive to longitudinal change in patients with SCA.

Cerebellar ataxias comprise a heterogeneous group of diseases characterized by motor and non-motor symptoms, which can be acquired, degenerative, or have a genetic cause, such as spinocerebellar ataxias (SCA). Usually, the genetic and neurodegenerative forms of cerebellar ataxias present a progressive and inevitable worsening of the clinical picture so that rehabilitation treatment is fundamental. Rehabilitation treatment includes physical therapy, respiratory therapy, speech, voice and swallowing therapy, occupational therapy, and new technologies, such as the use of exergames. The current treatment of patients with cerebellar ataxias, especially neurodegenerative forms, genetic or not, should include these different forms of rehabilitation, with the main objective of improving the quality of life of patients. RESUMO As ataxias cerebelares compreendem um grupo heterogêneo de doenças caracterizadas por sintomas motores e não motores, que podem ser adquiridas, degenerativas ou ter uma causa genética, como as ataxias espinocerebelares (AEC). Normalmente, as formas genéticas e neurodegenerativas de ataxias cerebelares apresentam uma piora progressiva e inexorável do quadro clínico e o tratamento com reabilitação é fundamental. O tratamento com reabilitação inclui a fisioterapia, fisioterapia respiratória, fonoterapia, terapia ocupacional e novas tecnologias, como o uso de exergames. O tratamento atual de pacientes com ataxias cerebelares, em particular as formas neurodegenerativas, genéticas ou não, deve incluir essas diferentes formas de reabilitação, com o objetivo principal de melhorar a qualidade de vida dos pacientes.

Cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS) is a late-onset, slow-progressing multisystem neurodegenerative disorder. Biallelic AAGGG repeat expansion in RFC1 has been identified as causative of this disease, and repeat conformation heterogeneity (ACAGG repeat) was also recently implied. To molecularly characterize this disease in Japanese patients with adult-onset ataxia, we accumulated and screened 212 candidate families by an integrated approach consisting of flanking PCR, repeat-primed PCR, Southern blotting and long-read sequencing using Sequel II, GridION or PromethION. We identified 16 patients from 11 families, of whom seven had ACAGG expansions [(ACAGG)exp/(ACAGG)exp] (ACAGG homozygotes), two had ACAGG and AAGGG expansions [(ACAGG)exp/(AAGGG)exp] (ACAGG/AAGGG compound heterozygotes) and seven had AAGGG expansions [(AAGGG)exp/(AAGGG)exp] (AAGGG homozygotes). The overall detection rate was 5.2% (11/212 families including one family having two expansion genotypes). Long-read sequencers revealed the entire sequence of both AAGGG and ACAGG repeat expansions at the nucleotide level of resolution. Clinical assessment and neuropathology results suggested that patients with ACAGG expansions have similar clinical features to previously reported patients with homozygous AAGGG expansions, although motor neuron involvement was more notable in patients with ACAGG expansions (even if one allele was involved). Furthermore, a later age of onset and slower clinical progression were implied in patients with ACAGG/AAGGG compound heterozygous expansions compared with either ACAGG or AAGGG homozygotes in our very limited cohort. Our study clearly shows the occurrence of repeat conformation heterogeneity, with possible different impacts on the affected nervous systems. The difference in disease onset and progression between compound heterozygotes and homozygotes might also be suspected but with very limited certainty due to the small sample number of cases in our study. Studies of additional patients are needed to confirm this.

Background Pathogenic variants in SPTAN1 have been linked to a remarkably broad phenotypical spectrum. Clinical presentations include epileptic syndromes, intellectual disability, and hereditary motor neuropathy. Objectives We investigated the role of SPTAN1 variants in rare neurological disorders such as ataxia and spastic paraplegia. Methods We screened 10,000 NGS datasets across two international consortia and one local database, indicative of the level of international collaboration currently required to identify genes causative for rare disease. We performed in silico modeling of the identified SPTAN1 variants. Results We describe 22 patients from 14 families with five novel SPTAN1 variants. Of six patients with cerebellar ataxia, four carry a de novo SPTAN1 variant and two show a sporadic inheritance. In this group, one variant (p.Lys2083del) is recurrent in four patients. Two patients have novel de novo missense mutations (p.Arg1098Cys, p.Arg1624Cys) associated with cerebellar ataxia, in one patient accompanied by intellectual disability and epilepsy. We furthermore report a recurrent missense mutation (p.Arg19Trp) in 15 patients with spastic paraplegia from seven families with a dominant inheritance pattern in four and a de novo origin in one case. One further patient carrying a de novo missense mutation (p.Gln2205Pro) has a complex spastic ataxic phenotype. Through protein modeling we show that mutated amino acids are located at crucial interlinking positions, interconnecting the three-helix bundle of a spectrin repeat. Conclusions We show that SPTAN1 is a relevant candidate gene for ataxia and spastic paraplegia. We suggest that for the mutations identified in this study, disruption of the interlinking of spectrin helices could be a key feature of the pathomechanism. © 2022 International Parkinson and Movement Disorder Society

Unverricht-Lundborg disease (ULD), also called progressive myoclonic epilepsy type 1, is usually characterized by the presence of ataxia associated with myoclonus and epileptic seizures without progressive cognitive deficit, presenting during late childhood and early adolescence. Currently, there is a growing body of evidence for atypical presentations of the disease with a milder phenotype or without the full symptomatology. We describe a case report of a late-onset phenotype with progressive myoclonus-ataxia syndrome accompanied by initial recurrent falls, resulting in specific phobia and agoraphobia starting at the age of 50 years old. The examination revealed multifocal myoclonus with cerebellar ataxia and electroencephalogram showed generalized polyspikes and spike-wave discharges. Electromyogram revealed positive myoclonus of 60-ms duration in the face and the presence of C reflex. A genetic study confirmed the diagnosis of ULD in the patient and other additional family members, presenting a wide range of intra-familial variability. We discuss the challenging differential diagnosis for such a misleading presentation and its possible underlying pathophysiological mechanisms. Our case report may contribute to broadening the age and clinical boundaries for this disease and emphasizes the intra-familial age and symptom variability. Based on a suggestive family history, the diagnosis of ULD should be considered in this context, even in older patients.

Patients with multiple system atrophy (MSA) are conventionally identified as having MSA-P (prominent parkinsonism) or MSA-C (prominent cerebellar ataxia) based on their predominant motor manifestations. The objective of the present study was to conduct latent class analysis (LCA) of various motor and nonmotor symptoms in early MSA to characterize data-driven subgroups.Sixty-one probable or possible MSA patients with disease durations of 3 years or less were included prospectively. LCAs were performed to identify similar clinical subgroups giving even weights to a wide range of MSA motor and nonmotor features. We ran latent models of up to 6 class solutions; the overall model fit was evaluated based on the parsimony of the derived classes, the fit indices, and clinical interpretability.The LCA outcome supported categorization of at least three subgroups of patients with early MSA: the largest class 1, labeled "moderate parkinsonism + extensive dysautonomia", included approximately half of our study patients and showed marked autonomic dysfunction with a burden of parkinsonism. The two other classes, class 2 "predominant parkinsonism + limited dysautonomia" and class 3 "predominant cerebellar symptoms + limited dysautonomia", showed marked core motor features (parkinsonism or cerebellar symptoms) with generally mild dysautonomia.To our knowledge, this is the first data-driven identification of disease subtypes covering various symptom constellations in early MSA (3 years from motor symptom onset). The present LCA result did not replicate the conventional motor classification and supported the heterogeneity within MSA-P and MSA-C subtypes.

Gordon Holmes syndrome (GHS) is a rare disease characterized by hypogonadotropic hypogonadism (HH), progressive cognitive decline and variable movement disorders. Mutations in RNF216 have been found to be associated with GHS. Here, we identify a novel homozygous RNF216 p.E650X mutation causing GHS. The proband presented with onset dysarthria and developed cerebellar ataxia and cognitive impairment, with a history of azoospermia at the age of 28 years. Cerebellar atrophy and white matter lesions were found in the cerebral hemispheres and brainstem. Low gonadotropin serum levels were also observed. Whole-exome sequencing (WES) revealed a novel homozygous nonsense variant in RNF216, c.1948GT; p.E650X. Our finding furthers the genetic knowledge of GHS and extends the ethnic distribution of RNF216 mutations.

Autoimmune cerebellar ataxia (AICA) is a general term for diseases in which the cerebellum is damaged by an autoimmune mechanism. For the diagnosis of the AICA, anti-thyroid antibodies (anti-thyroid peroxidase antibody and anti-thyroglobulin antibody), anti-glutamic acid decarboxylase (GAD) antibodies, and anti-gliadin antibodies are measured. Immunotherapy is known to be effective for AICA, but some patients with effective immunotherapy lack autoantibodies associated with cerebellar ataxia. The purpose of this study was to clarify whether the effectiveness of immunotherapy in patients with suspected AICA could be predicted by anti-mouse cerebellar tissue-derived antigen antibody tests.This study was conducted on 25 patients with idiopathic cerebellar ataxia (excluding multiple system atrophy, hereditary spinocerebellar degeneration, cancer-bearing patients, and patients taking phenytoin) who received immunotherapy from 2005 to 2016 at Tokyo Medical University Hachioji Medical Center. The patients were suspected of having AICA because they were positive for cerebellar ataxia-related autoantibodies (anti-thyroid antibody, anti-GAD antibody, anti-gliadin antibody, or anti-transglutaminase 6 antibody) or other autoantibodies. Antibodies that bind to mouse cerebellar tissue-derived antigens were defined as "anti-mouse cerebellar tissue-derived antigen antibodies" in this study, and their IgG-class antibodies were comprehensively measured using a slot blot.Anti-mouse cerebellar tissue-derived antigen antibody test results were correlated with immunotherapy efficacy. Furthermore, the combination of anti-mouse cerebellar tissue-derived antigen and anti-GAD antibody tests could predict the effectiveness of immunotherapy with 83% sensitivity and 100% specificity, while the combination of the anti-mouse cerebellar tissue-derived antigen, anti-GAD, and anti-gliadin (IgA class) antibody tests could predict the effectiveness of immunotherapy with 94% sensitivity and 86% specificity.Anti-mouse cerebellar tissue-derived antigen antibody tests could help to provide useful information for immunotherapy administration to patients with idiopathic cerebellar ataxia suspected to be AICA.

Cerebellar ataxia (CA) is concerned with the incoordination of movement caused by cerebellar dysfunction. Movements of the eyes, speech, trunk, and limbs are affected. Conventional machine learning approaches utilizing centralised databases have been used to objectively diagnose and quantify the severity of CA. Although these approaches achieved high accuracy, large scale deployment will require large clinics and raises privacy concerns. In this study, we propose an image transformation-based approach to leverage the advantages of state-of-the-art deep learning with federated learning in diagnosing CA. We use motion capture sensors during the performance of a standard neurological balance test obtained from four geographically separated clinics. The recurrence plot, melspectrogram, and poincaré plot are three transformation techniques explored. Experimental results indicate that the recurrence plot yields the highest validation accuracy (86.69%) with MobileNetV2 model in diagnosing CA. The proposed scheme provides a practical solution with high diagnosis accuracy, removing the need for feature engineering and preserving data privacy for a large-scale deployment.

Recently, an intronic biallelic (AAGGG)n repeat expansion in RFC1 was shown to be a cause of CANVAS and adult-onset ataxia in multiple populations. As the prevalence of the RFC1 repeat expansion in Dutch cases was unknown, we retrospectively tested 9 putative CANVAS cases and two independent cohorts (A and B) of 395 and 222 adult-onset ataxia cases, respectively, using the previously published protocol and, for the first time optical genome mapping to determine the size of the expanded RFC1 repeat. We identified the biallelic (AAGGG)n repeat expansion in 5/9 (55%) putative CANVAS patients and in 10/617 (1.6%; cohorts A + B) adult-onset ataxia patients. In addition to the AAGGG repeat motif, we observed a putative GAAGG repeat motif in the repeat expansion with unknown significance in two adult-onset ataxia patients. All the expanded (AAGGG)n repeats identified were in the range of 800–1299 repeat units. The intronic biallelic RFC1 repeat expansion thus explains a number of the Dutch adult-onset ataxia cases that display the main clinical features of CANVAS, and particularly when ataxia is combined with neuropathy. The yield of screening for RFC1 expansions in unselected cohorts is relatively low. To increase the current diagnostic yield in ataxia patients, we suggest adding RFC1 screening to the genetic diagnostic workflow by using advanced techniques that attain long fragments.

Cerebellar ataxia (CA) is a condition in which cerebellar dysfunction leads to movement disorders such as dysmetria, asynergy and dysdiadochokinesia. This study investigates the therapeutic effects of Melittin (MEL) on 3-acetylpyridine-induced (3-AP) cerebellar ataxia (CA) rat model. Initially, CA rat models were generated by 3-AP administration followed by the intraperitoneal injection of MEL. Then, motor performance and electromyography (EMG) activity were assessed. Afterwards, the pro-inflammatory cytokines were analyzed in the cerebellar tissue. Moreover, the anti-apoptotic role of MEL in CA and its relationship with the protection of Purkinje cells were explored. The findings showed that the administration of MEL in a 3-AP model of ataxia improved motor coordination (P 0.001) and neuro-muscular activity (p 0.05), prevented the cerebellar volume loss (P 0.01), reduced the level of inflammatory cytokines (p 0.05) and thwarted the degeneration of Purkinje cells against 3-AP toxicity (P 0.001). Overall, the findings imply that the MEL attenuates the 3-AP-induced inflammatory response. As such, it could be used as a treatment option for CA due to its anti-inflammatory effects.

Item does not contain fulltext Spinocerebellar ataxias (SCA) comprise a rare, genetic subgroup within the degenerative ataxias and are dominantly inherited, with up to 48 recognized genetic subtypes. While an updated review on the management of degenerative ataxia is published recently, an evidence-based review focussed on the management of SCA is lacking. Here, we reviewed the pharmacological and non-pharmacological management of SCA by conducting a systematic review on Medline Ovid and Scopus. Of 29,284 studies identified, 47 studies (pharmacological: n = 25; non-pharmacological: n = 22) that predominantly involved SCA patients were included. Twenty studies had a high risk of bias based on the Cochrane's Collaboration risk of bias tool. As per the European Federation of Neurological Societies 2004 guideline for therapeutic intervention, the remaining 27 studies were of Class I (n = 4) and Class II (n = 23) evidence. Only two therapies had Level A recommendations for the management of ataxia symptoms: riluzole and immediate in-patient neurorehabilitation. Ten therapies had Level B recommendations for managing ataxia symptoms and require further investigations with better study design. These include high dose valproate acid, branched-chain amino acid, intravenous trehalose; restorative rehabilitation using cycling regimen and videogame; and cerebellar stimulations using transcranial direct current stimulation and transcranial magnetic stimulation. Lithium and coaching on psychological adjustment received Level B recommendation for depressive symptoms and quality of life, respectively. Heterogeneous study designs, different genotypes, and non-standardized clinical measures alongside short duration and small sample sizes may hamper meaningful clinical translation. Therefore, rating of recommendations only serve as points of reference. 23 p.

Introduction: The impact of deep brain stimulation (DBS) on speech rhythm and its mechanism remains unclear. We investigated speech rhythm characteristics of patients with Parkinson's disease (PD) treated with subthalamic nucleus (STN) DBS to understand the underlying pathophysiology better. Methods: We enrolled a total of 105 participants and evaluated speech rhythm performances among patients with PD who had undergone STN-DBS (the PD-DBS group), patients with PD treated only with medication (the PD-Med group), patients with cerebellar ataxia (the CA group), and healthy controls (the HC group). Each participant was asked to repeat the syllable/pa/at a comfortable self-chosen steady pace. A widely-used software (the Motor Speech Profile) program performed an acoustic analysis. Results: Compared to the PD-Med and HC groups, speech rate instability (DDKjit) was significantly higher in the PD-DBS and CA groups (p < 0.01). However, after DBS was turned off, the DDKjit of the PD-DBS group improved to a level comparable to that of the PD-Med and HC groups. In contrast to the significantly higher variability of speech volume (DDKcvi) in the CA group, the PD-DBS group showed similar DDKcvi to the PD-Med and HC groups. Conclusions: STN-DBS affects the speech rate stability of patients with PD. Speech rhythm disorders caused by STN-DBS were phenotypically similar to that in CA in terms of interval variability but different regarding amplitude variability. Further studies are warranted to elucidate the underlying pathophysiology of speech rhythm disorders in PD patients treated with DBS.

A 60-year-old patient had progressive imbalance. Examination revealed saccadic smooth pursuit, downbeat nystagmus, ataxia of stance and gait, and reduced vibration sense. Video head impulse and caloric testing both showed vestibulo-ocular reflex (VOR) deficits (figure). The patient has cerebellar ataxia with neuronopathy and vestibular areflexia syndrome.1,2 Slow head turns while looking at an earth-fixed target produce saccadic rather than smooth compensatory eye movements (Videos 1) due to impairment of both the VOR and smooth pursuit (the visually enhanced VOR): 1 simple bedside test, 2 clinical signs, and 1 precise diagnosis.

Fragile X-associated tremor/ataxia syndrome (FXTAS) is an adult-onset neurodegenerative disorder caused by FMR1 premutation expansion of CGG repeats. FXTAS can be misdiagnosed with many neurodegenerative disorders manifesting with cerebellar ataxias owing to their overlapping clinical and radiological features. The frequency of the FMR1 premutation allele in Japan has not been fully determined. Herein, we aimed to determine the frequency of FMR1 premutation alleles in Japanese patients with undiagnosed cerebellar ataxia and multiple system atrophy, using repeat-primed PCR in 186 patients with adult onset of undiagnosed cerebellar ataxia and 668 patients with multiple system atrophy, to identify expanded CGG repeats as well as to detect AGG interruptions within the expanded alleles. The size of expansions was estimated using fragment length analysis of PCR products obtained by conventional PCR employing a pair of unique primers flanking the repeat sequence. We identified FMR1 premutation alleles in three male patients. One patient revealed 84 repeat units with one AGG interruption and another patient showed 103 repeat units. Both had presented with sporadic cerebellar ataxia, giving an estimated frequency of 3.7% among Japanese male patients with sporadic cerebellar ataxia with age at onset above 50 years. One patient with the clinical diagnosis of multiple system atrophy harbored 60 repeat units with four AGG interruptions. FMR1 intermediate alleles were observed in two males and one female among the multiple system atrophy patients. We found that genetic tests for FMR1 premutation should be considered in Japanese male patients with cerebellar ataxia with the age at onset above 50 years.

Spastic ataxia is characterized by the combination of cerebellar ataxia with spasticity and other pyramidal features. It is the hallmark of some hereditary ataxias, but it can also occur in some spastic paraplegias and acquired conditions. It often presents with heterogenous clinical features with other neurologic and non-neurological symptoms, resulting in complex phenotypes. In this review, the differential diagnosis of spastic ataxias are discussed and classified in accordance with inheritance. Establishing an organized classification method based on mode inheritance is fundamental for the approach to patients with these syndromes. For each differential, the clinical features, neuroimaging and genetic aspects are reviewed. A diagnostic approach for spastic ataxias is then proposed.

BACKGROUND AND PURPOSE The aim of this study was to identify the long-term radiological changes, autoantibody specificities, and clinical course in a patient with kelch-like protein 11 (KLHL11)-associated paraneoplastic neurological syndrome (PNS). METHODS Serial brain magnetic resonance images were retrospectively assessed. To test for KLHL11 autoantibodies, longitudinal cerebrospinal fluid (CSF) and serum samples were screened by Phage-display ImmunoPrecipitation and Sequencing (PhIP-Seq). Immunohistochemistry was also performed to assess for the presence of KLHL11 in the patient's seminoma tissue. RESULTS A 42-year-old man presented with progressive ataxia and sensorineural hearing loss. Metastatic seminoma was detected 11 months after the onset of the neurological symptoms. Although immunotherapy was partially effective, his cerebellar ataxia gradually worsened over the next 8 years. Brain magnetic resonance imaging revealed progressive brainstem and cerebellar atrophy with a "hot-cross-bun sign", and low-signal intensity on susceptibility-weighted imaging (SWI) in the substantia nigra, red nucleus and dentate nuclei. PhIP-Seq enriched for KLHL11-derived peptides in all samples. Immunohistochemical staining of mouse brain with the patient CSF showed co-localization with a KLHL11 commercial antibody in the medulla and dentate nucleus. Immunohistochemical analysis of seminoma tissue showed anti-KLHL11 antibody-positive particles in cytoplasm. CONCLUSIONS This study suggests that KLHL11-PNS should be included in the differential diagnosis for patients with brainstem and cerebellar atrophy and signal changes not only on T2-FLAIR but also on SWI, which might otherwise be interpreted as secondary to a neurodegenerative disease such as multiple system atrophy.

Vanishing White Matter Disease (VWMD) is a rare autosomal recessive leukoencephalopathy . The classical presentation is characterized by a severe cerebellar ataxia, spasticity, neurological deterioration with a chronic progressive course and episodes of acute neurological deterioration after stress conditions.We report a 52-year-old man with VWMD and atypical features who manifested two major events of transient aphasia eleven years apart with complete recovery in 48 hours. No cognitive decline was present. Brain MRI revealed typical aspects of VWMD including diffuse leukoencephalopathy with relative sparing of U-fibers. We identified the presence of c.592G>A (p.Glu198Lys) and c.1360 C>T (p.Pro454Ser) mutations in EIF2B5.

In recent years, with advances in molecular genetics, many new mutations with various ataxic syndromes have been identified. Recently, homozygous sequestosome 1 (SQSTM1) gene variant with a progressive childhood-onset cerebellar ataxia, dystonia and gaze palsy was described. Here we describe a patient with progressive cerebellar ataxia and gaze palsy, as well as myoclonus, cognitive impairment and growth retardation with a homozygous SQSTM1 variant NM_003900.5:c.55G > T (p.Glu19*). Our case had brainstem lesions on brain magnetic resonance imaging that have not been previously reported. This novel finding expands the SQSTM1 gene-associated neuroradiologic spectrum. Homozygous SQSTM1 variant should be considered in the differential diagnosis in patients presenting with cerebellar findings, gaze palsy, and cognitive impairment to facilitate early diagnosis and genetic counseling.

INTRODUCTION Wolfram syndrome is a rare autosomal recessive genetic disease characterized by diabetes insipidus, diabetes mellitus, optic atrophy and deafness. A neurodegenerative syndrome is usually associated, including cerebellar ataxia. A few cases of central apnea have been reported in the literature. Here, we report a case of Wolfram syndrome with respiratory symptoms that led to the discovery of central apneas as well as complicated and delayed weaning in an intensive care unit (ICU). OBSERVATION The patient is a 39-year-old woman diagnosed with Wolfram syndrome who was admitted to an ICU for septic shock. She experienced difficult weaning before central apneas were observed while spontaneous ventilation was being attempted. After two extubation failures, cerebral MRI was performed and revealed parenchymatous atrophy of the posterior brain fossa involving the cerebral trunk, cerebellar peduncles, as well as both cerebellum hemispheres and the cerebellar vermis. Even after the patient was tracheotomized, central apneas persisted when the patient breathed spontaneously with her tracheotomy, necessitating nocturnal ventilation. CONCLUSION While central apneas Wolfram syndrome remain rare, they should be systematically investigated due to their association with severe morbimortality.