Fragile X-associated tremor/ataxia syndrome treated with multitarget deep brain stimulation.

Fragile X-associated tremor/ataxia syndrome (FXTAS) is a progressive hereditary neurodegenerative disorder which causes intention tremor and cerebellar ataxia. It typically affects the ageing population. Deep brain stimulation (DBS) is widely accepted in the treatment of common movement disorders and has been trialled in treating rare and complex neurodegenerative disorders. We report a case of a man in his 40s with a long history of tremor affecting his hands. MRI brain revealed high T2 signal in the middle cerebellar peduncles. Genetic testing revealed FMR1 premutation confirming the diagnosis of FXTAS. Subsequently, he was treated with multitarget DBS of the ventralis intermediate nucleus and ventralis oralis posterior nuclei bilaterally, with excellent neurological function at 9 years follow-up. This case suggests multitarget DBS for FXTAS with neurophysiology-guided DBS programming can provide excellent long-term tremor suppression in selected patients.

Effectiveness of High-Frequency Repetitive Transcranial Magnetic Stimulation in Patients With Spinocerebellar Ataxia Type 3.

OBJECTIVE: To investigate the effectiveness of high-frequency repetitive transcranial magnetic stimulation (HF-rTMS) on improvement of clinical symptoms in patients with spinocerebellar ataxia type 3 (SCA3). METHODS: Sixteen SCA3 participants diagnosed by genetic testing were enrolled in this sham-controlled and double-blind trial. They received either a 2-week 10-Hz rTMS intervention or sham stimulation targeting the vermis and cerebellum. The Scale for Assessment and Rating of Ataxia and the International Cooperative Ataxia Rating Scale were completed at baseline and poststimulation. RESULTS: Compared with baseline, the HF-rTMS group demonstrated a significant improvement in the total Scale for Assessment and Rating of Ataxia ( P < 0.0001) and the International Cooperative Ataxia Rating Scale scores ( P = 0.002). After 2-week treatment, the real group exhibited decreasing pattern in 3 subgroups, especially for limb kinetic function ( P < 0.0001). CONCLUSIONS: Short-term HF-rTMS treatment is a potentially promising and feasible tool for rehabilitation in patients with SCA3. Studies with long-term follow-up need to be carried out in the future and further need to assess gait, limb kinetic function, speech and oculomotor disorders.

Comparing Cerebellar tDCS and Cerebellar tACS in Neurodegenerative Ataxias Using Wearable Sensors: A Randomized, Double-Blind, Sham-Controlled, Triple-Crossover Trial.

Cerebellar transcranial direct current stimulation (tDCS) represents a promising therapeutic approach for both motor and cognitive symptoms in neurodegenerative ataxias. Recently, transcranial alternating current stimulation (tACS) was also demonstrated to modulate cerebellar excitability by neuronal entrainment. To compare the effectiveness of cerebellar tDCS vs. cerebellar tACS in patients with neurodegenerative ataxia, we performed a double-blind, randomized, sham controlled, triple cross-over trial with cerebellar tDCS, cerebellar tACS or sham stimulation in twenty-six participants with neurodegenerative ataxia. Before entering the study, each participant underwent motor assessment with wearable sensors considering gait cadence (steps/minute), turn velocity (degrees/second) and turn duration (seconds), and a clinical evaluation with the scale for the Assessment and Rating of Ataxia (SARA) and the International Cooperative Ataxia Rating Scale (ICARS). After each intervention, participants underwent the same clinical assessment along with cerebellar inhibition (CBI) measurement, a marker of cerebellar activity. The gait cadence, turn velocity, SARA, and ICARS significantly improved after both tDCS and tACS, compared to sham stimulation (all p<0.010). Comparable effects were observed for CBI (p<0.001). Overall, tDCS significantly outperformed tACS on clinical scales and CBI (p<0.01). A significant correlation between changes of wearable sensors parameters from baseline and changes of clinical scales and CBI scores was detected. Cerebellar tDCS and cerebellar tACS are effective in ameliorating symptoms of neurodegenerative ataxias, with the former being more beneficial than the latter. Wearable sensors may serve as rater-unbiased outcome measures in future clinical trials. ClinicalTrial.gov Identifier: NCT05621200.

CSTB gene replacement improves neuroinflammation, neurodegeneration and ataxia in murine type 1 progressive myoclonus epilepsy.

EPM1 is the most common form of Progressive Myoclonus Epilepsy characterized by late-childhood onset, ever-worsening and disabling myoclonus, seizures, ataxia, psychiatric disease, and shortened lifespan. EPM1 is caused by expansions of a dodecamer repeat sequence in the promoter of CSTB (cystatin B), which dramatically reduces, but does not eliminate, gene expression. The relatively late onset and consistent presence of a minimal amount of protein product makes EPM1 a favorable target for gene replacement therapy. If treated early, these children's normally developed brains could be rescued from the neurodegeneration that otherwise follows, and their cross-reactive immunological material (CRIM) positive status greatly reduces transgene related toxicity. We performed a proof-of-concept CSTB gene replacement study in Cstb knockout mice by introducing full-length human CSTB driven by the CBh promoter packaged in AAV9 and administered at postnatal days 21 and 60. Mice were sacrificed at 2 or 9 months of age, respectively. We observed significant improvements in expression levels of neuroinflammatory pathway genes and cerebellar granule cell layer apoptosis, as well as amelioration of motor impairment. The data suggest that gene replacement is a promising therapeutic modality for EPM1 and could spare affected children and families the ravages of this otherwise severe neurodegenerative disease.

Patient pathways for rare diseases in Europe: ataxia as an example.

BACKGROUND: Progressive ataxias are rare and complex neurological disorders that represent a challenge for the clinicians to diagnose and manage them. This study explored the patient pathways of individuals attending specialist ataxia centres (SAC) compared with non-specialist settings. We investigated specifically how diagnosis was reached, the access to healthcare services, treatments, and care satisfaction. The focus of this study was on early intervention, coordination of treatment to understand the care provision in different countries. METHODS: A patient survey was done in the UK, Germany and Italy to gather information about diagnosis and management of the ataxias in specialist (SAC) and non-specialist settings, utilisation of other primary and secondary health care services, and patients' satisfaction of received treatment. RESULTS: Patients gave positive feedback about the role of SAC in understanding their condition, ways to manage their ataxia (p < 0.001; UK) and delivering care adapted to their needs (p < 0.001; UK), in coordinating referrals to other healthcare specialists, and in offering opportunities to take part in research studies. Similar barriers for patients were identified in accessing the SACs among the selected countries, UK, Germany, and Italy. CONCLUSIONS: This study provides crucial information about the ataxia patients care pathways in three European countries. Overall, the results showed a trend in patients' satisfaction being better in SAC compared to non-SAC. The outcomes can be used now for policy recommendations on how to improve treatment and care for people with these very rare and complex neurological diseases across Europe.

A patient with neuropathy and ataxia: what do I have to consider?

PURPOSE OF REVIEW: An increasing number of peripheral neuro(no)pathies are identified as involving other components of the neurological system, particularly those that further impair balance. Here we aim to outline an evidence-based approach to the diagnosis of patients who present with a somatosensory disorder which also involves at least one other area of neurological impairment such as the vestibular, auditory, or cerebellar systems. RECENT FINDINGS: Detailed objective investigation of patients who present with sensory impairment, particularly where the degree of imbalance is greater than would be expected, aids the accurate diagnosis of genetic, autoimmune, metabolic, and toxic neurological disease. SUMMARY: Diagnosis and management of complex somatosensory disorders benefit from investigation which extends beyond the presenting sensory impairment.

The Therapeutic Potential of Non-Invasive and Invasive Cerebellar Stimulation Techniques in Hereditary Ataxias.

The degenerative ataxias comprise a heterogeneous group of inherited and acquired disorders that are characterized by a progressive cerebellar syndrome, frequently in combination with one or more extracerebellar signs. Specific disease-modifying interventions are currently not available for many of these rare conditions, which underscores the necessity of finding effective symptomatic therapies. During the past five to ten years, an increasing number of randomized controlled trials have been conducted examining the potential of different non-invasive brain stimulation techniques to induce symptomatic improvement. In addition, a few smaller studies have explored deep brain stimulation (DBS) of the dentate nucleus as an invasive means to directly modulate cerebellar output, thereby aiming to alleviate ataxia severity. In this paper, we comprehensively review the clinical and neurophysiological effects of transcranial direct current stimulation (tDCS), repetitive transcranial magnetic stimulation (rTMS), and dentate nucleus DBS in patients with hereditary ataxias, as well as the presumed underlying mechanisms at the cellular and network level and perspectives for future research.

Episodic Ataxias: Primary and Secondary Etiologies, Treatment, and Classification Approaches.

Background: Episodic ataxia (EA), characterized by recurrent attacks of cerebellar dysfunction, is the manifestation of a group of rare autosomal dominant inherited disorders. EA1 and EA2 are most frequently encountered, caused by mutations in KCNA1 and CACNA1A. EA3-8 are reported in rare families. Advances in genetic testing have broadened the KCNA1 and CACNA1A phenotypes, and detected EA as an unusual presentation of several other genetic disorders. Additionally, there are various secondary causes of EA and mimicking disorders. Together, these can pose diagnostic challenges for neurologists. Methods: A systematic literature review was performed in October 2022 for 'episodic ataxia' and 'paroxysmal ataxia', restricted to publications in the last 10 years to focus on recent clinical advances. Clinical, genetic, and treatment characteristics were summarized. Results: EA1 and EA2 phenotypes have further broadened. In particular, EA2 may be accompanied by other paroxysmal disorders of childhood with chronic neuropsychiatric features. New treatments for EA2 include dalfampridine and fampridine, in addition to 4-aminopyridine and acetazolamide. There are recent proposals for EA9-10. EA may also be caused by gene mutations associated with chronic ataxias (SCA-14, SCA-27, SCA-42, AOA2, CAPOS), epilepsy syndromes (KCNA2, SCN2A, PRRT2), GLUT-1, mitochondrial disorders (PDHA1, PDHX, ACO2), metabolic disorders (Maple syrup urine disease, Hartnup disease, type I citrullinemia, thiamine and biotin metabolism defects), and others. Secondary causes of EA are more commonly encountered than primary EA (vascular, inflammatory, toxic-metabolic). EA can be misdiagnosed as migraine, peripheral vestibular disorders, anxiety, and functional symptoms. Primary and secondary EA are frequently treatable which should prompt a search for the cause. Discussion: EA may be overlooked or misdiagnosed for a variety of reasons, including phenotype-genotype variability and clinical overlap between primary and secondary causes. EA is highly treatable, so it is important to consider in the differential diagnosis of paroxysmal disorders. Classical EA1 and EA2 phenotypes prompt single gene test and treatment pathways. For atypical phenotypes, next generation genetic testing can aid diagnosis and guide treatment. Updated classification systems for EA are discussed which may assist diagnosis and management.

Neuroblastic Tumor Recurrence Associated With Opsoclonus Myoclonus Ataxia Syndrome Relapse a Decade After Initial Resection and Treatments.

Opsoclonus myoclonus ataxia syndrome (OMAS) is a rare disorder that causes significant neurodevelopmental sequelae in children. Approximately half of pediatric OMAS cases are paraneoplastic, typically associated with localized neuroblastic tumors. Since early persistence or relapse of OMAS symptoms is common even after tumor resection, OMAS relapses may not routinely prompt reevaluation for recurrent tumors. We report a 12-year-old girl with neuroblastic tumor recurrence associated with OMAS relapse a decade after initial treatment. Providers should be aware of tumor recurrence as a trigger for distant OMAS relapse, raising intriguing questions about the role of immune surveillance and control of neuroblastic tumors.

[Gene Therapy for Ataxias]. / Gentherapie für Ataxien.

Ataxias are progressive diseases that are usually the result of cerebellar degeneration. Ataxias are divided into genetic, sporadic degenerative and acquired (secondary) forms. While there are established therapies for acquired (secondary) ataxias, genetic and sporadic degenerative ataxias are currently not medically treatable. For these ataxias, the development of somatic gene therapies is a promising avenue. The goals of gene therapies for genetic ataxias are to inactivate deleterious genes by gene silencing or to replace or correct a non-functional gene. Another option, which may also be considered for sporadic degenerative ataxias, are therapies that involve transferring new or modified genes. Gene therapies are being actively developed for the more common ataxias, such as Friedreich's ataxia, certain spinocerebellar ataxias, and multiple system atrphy, and initial phase I trials are underway.

M1 and Cerebellar tDCS for MSA-C: a Double-Blind, Randomized, Sham-Controlled, Crossover Study.

The effect of transcranial direct current stimulation (tDCS) for cerebellar-dominant multiple-system atrophy (MSA-C) is not well elucidated, yet. This study aimed to investigate the effect of tDCS on the primary motor cortex (M1) and cerebellum in patients with MSA-C. We recruited probable MSA-C patients and performed three single sessions of tDCS at each visit in random order (M1, cerebellum or sham). Cerebellar ataxia was evaluated with the International Cooperative Ataxia Rating Scale (ICARS) and objective gait and static balance analyses both before and after each stimulation session. Additionally, we also evaluated the factors related with objective improvement from each stimulation. Sixteen participants were enrolled, and one dropped out after 2 sessions of stimulation due to consent withdrawal. The gait velocity, step time and single support time all significantly improved after the M1 and cerebellar tDCS treatment compared with the sham stimulation while there was no difference in the improvement of ICARS and posturography results among 3 stimulations. In terms of the related factors with improvement of gait velocity, the disease duration, baseline gait speed and single support times were correlated after M1 stimulation, while a higher ICARS score and baseline gait speed in cerebellar stimulation. There were no adverse effects reported after the tDCS sessions. Our results demonstrated that both M1 and cerebellar tDCS demonstrated benefits for MSA-C patients without significant complications. Considering the different related factors with improvement at each stimulation, the mechanism would be different between M1 and cerebellar stimulations.

Utility of Anorectal Testing to Predict Outcomes With Pelvic Floor Physical Therapy in Chronic Constipation: Pragmatic Trial.

BACKGROUND & AIMS: We performed a clinical trial that aimed to inform the clinical utility of anorectal manometry (ARM) and balloon expulsion time (BET) as up-front tests to predict outcomes with community-based pelvic floor physical therapy as the next best step to address chronic constipation after failing an empiric trial of soluble fiber supplementation or osmotic laxatives. METHODS: We enrolled 60 treatment-naïve patients with Rome IV functional constipation failing 2 weeks of soluble fiber supplementation or osmotic laxatives. All patients underwent ARM/BET (London protocol) followed by community-based pelvic floor physical therapy. Outcomes were assessed at baseline and 12 weeks. The primary end point was clinical response (Patient Assessment of Constipation-Symptoms instrument). RESULTS: Fifty-three patients completed pelvic rehabilitation and the post-treatment questionnaire. Contemporary frameworks define dyssynergia on balloon expulsion time and dyssynergic patterns (ARM), but these parameters did not inform clinical outcomes (area under the curve [AUC], <0.6). Squeeze pressure (>192.5 mm Hg on at least 1 of 3 attempts; sensitivity, 47.6%; specificity, 83.9%) and limited squeeze duration (inability to sustain 50% of squeeze pressure for >20 seconds; sensitivity, 71.4%; specificity, 58.1%) were the strongest predictors of clinical outcomes. Combining BET with squeeze duration (BET greater than 6.5 seconds and limited squeeze duration) improved predictive accuracy (AUC, 0.75; 95% CI, 0.59-0.90). BET poorly predicted outcomes as a single test (AUC, 0.54; 95% CI, 0.38-0.69). CONCLUSIONS: Using ARM to evaluate squeeze profiles, rather than dyssynergia, appears useful to screen patients with chronic constipation for up-front pelvic floor physical therapy based on likelihood of response. BET appears noninformative as a single screening test (ClinicalTrials.gov: NCT04159350).

Therapeutic Misestimation in Patients with Degenerative Ataxia: Lessons from a Randomized Controlled Trial.

BACKGROUND: The absence of effective treatments may render patients with degenerative cerebellar ataxias susceptible to a placebo response, which could affect the outcome of clinical trials. OBJECTIVE: To retrospectively examine expectations of benefit in participants of an ataxia trial and identify determinants of possible therapeutic misestimation. METHODS: Individuals with spinocerebellar ataxia type 3 who participated in a randomized, double-blind, sham-controlled trial received a custom-designed questionnaire about short-term and long-term treatment expectations, allocation preferences, and interpretation of treatment arm assignment based on the presence or absence of clinical improvement. To evaluate whether expectations were specifically related to the application of cerebellar transcranial direct current stimulation (tDCS) or more generally reflect an overly positive attitude of patients with ataxia toward trial participation and results, the last questions involved a hypothetical scenario in which an oral drug was tested against placebo with an aim identical to that of our tDCS study. RESULTS: All 20 trial participants completed the questionnaire. If allocated to the active treatment arm, 75% of patients expected short-term health benefits and 55% thought they would still have less severe ataxia at 1-year follow-up compared with baseline. After 2 weeks, an average reduction in ataxia severity of 31.5% (standard deviation, 22.2%) was anticipated. Conversely, 65% associated a lack of improvement with probable or definite allocation to the placebo group. High expectations of benefit were neither related to the type of intervention nor to clinical or demographic characteristics. CONCLUSION: Therapeutic misestimation is common in patients with degenerative ataxia and requires special attention in future trials. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Multidisciplinary management of posterior fossa dural arteriovenous fistula: A single-center experience.

PURPOSE: The management of posterior fossa dural arteriovenous fistulas (pfDAVFs) is challenging. Here, we show how multidisciplinarity leads to their successful management, even in complex cases. METHODS: All pfDAVFs managed from 2010 to 2019 at our center were reviewed. The preoperative clinical and radiological characteristics, their management and the occlusion rate were retrieved. The radiological and functional outcomes were retrieved at discharge and last follow-up (FU). RESULTS: n=27 patients were included (6 females, mean age: 61-years-old, mean FU: 22.5 months). n=8 patients presented with cerebral hemorrhage. Among patients with ruptured pfDAVFs, n=7 had headache, n=4 had ataxia, and n=2 had impaired level of consciousness. In the unruptured group N (n=19), n=7 patients had headache, n=6 patients had focal neurological deficit, n=4 patients had tinnitus, n=3 (had ataxia, and one presented with seizure. n=24 patients were treated by endovascular therapy (EVT), n=2 patients were treated by microsurgery (MS) and n=1 patient was managed with a combined approach. Re-treatment was necessary in n=6 patients. n=24 patients showed total exclusion at last FU. n=2 patients died during the first 30 days; n=1 patient died during FU. CONCLUSIONS: While EVT should be advocated as the first line therapy whenever possible, MS should not be banned from the treatment armamentarium. Neurosurgeons must be able to achieve direct surgical occlusion when the angioarchitecture speaks against EVT.

ClearSpeechTogether: a Rater Blinded, Single, Controlled Feasibility Study of Speech Intervention for People with Progressive Ataxia.

BACKGROUND: Progressive ataxias frequently lead to speech disorders and consequently impact on communication participation and psychosocial wellbeing. Whilst recent studies demonstrate the potential for improvements in these areas, these treatments generally require intensive input which can reduce acceptability of the approach. A new model of care-ClearSpeechTogether-is proposed which maximises treatment intensity whilst minimising demands on clinician. This study aimed to establish feasibility and accessibility of this approach and at the same time determine the potential benefits and adverse effects on people with progressive ataxias. METHOD: This feasibility study targeted people with progressive ataxia and mild-moderate speech and gross motor impairment. ClearSpeechTogether consisted of four individual sessions over 2 weeks followed by 20 patient-led group sessions over 4 weeks. All sessions were provided online. Quantitative and qualitative data were collected for evaluation. RESULTS: Nine participants completed treatment. Feasibility and acceptability were high and no adverse effects were reported. Statistical tests found significantly reduced vocal strain, improved reading intelligibility and increased participation and confidence. Participant interviews highlighted the value of group support internalisation of speech strategies and psycho-social wellbeing. DISCUSSION: ClearSpeechTogether presented a feasible, acceptable intervention for a small cohort of people with progressive ataxia. It matched or exceeded the outcomes previously reported following individual therapy. Particularly notable was the fact that this could be achieved through patient led practice without the presence of a clinician. Pending confirmation of our results by larger, controlled trials, ClearSpeechTogether could represent an effective approach to manage speech problems in ataxia.

Dystonia, Chorea, and Ataxia: Three Challenging Cases.

Movement disorders comprise a heterogeneous and complex group of neurological disorders that increase (hyperkinetic) or decrease (hypokinetic) the speed or amplitude of movements, or disrupt their coordinated sequencing. In this article, we describe three instructive cases, exemplifying classic movement disorders, namely dystonia, chorea, and ataxia. We highlight the diagnostic approach based on clinical clues, syndromic reasoning, evaluation, and management recommendations. Each case ends with key messages for the clinicians.

Effects of a core stability exercise program on balance and coordination in children with cerebellar ataxic cerebral palsy.

OBJECTIVE: To evaluate the effects of a core stability exercise program on balance, coordination, and severity of ataxia in children with cerebellar ataxic cerebral palsy (CP). METHODS: Forty children with cerebellar ataxic CP (mean age: 6.75±1.35 years) were randomly assigned to a control group and an intervention group for 2 months of follow-up. The control group received a standard physical therapy program three times weekly (1 h per session), while the intervention group received a core stability program for 30 min, in addition to the selected physical therapy program. Both groups were evaluated pre-treatment and post-treatment using the Scale for the Assessment and Rating of Ataxia, the Balance Error Scoring Systems scale, Bruininks-Oseretsky tests of motor proficiency, and HUMAC balance system scores. RESULTS: We found statistically significant reductions in the severity of ataxia, as well as improved balance and coordination in both groups, with stronger effects observed in the intervention group (P<0.05). CONCLUSION: The core stability program can improve balance and coordination in children with cerebellar ataxic CP when incorporated with a standard physical therapy program.

Non-invasive electrical stimulation in patients with neurodegenerative ataxia and spasticity: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND AND PURPOSE: There are limited treatment options for patients with neurodegenerative ataxia and spasticity. Non-invasive electrostimulation (NES) is receiving increasing interest because of its ease of implementation, cost-effectiveness and safety. A meta-analysis was conducted to evaluate the efficacy of NES. METHODS: MEDLINE and Embase were screened for studies using NES in ataxias and spasticity. Key outcome measurements of effectiveness included changes in (1) Modified Ashworth Scale (MAS) scores, (2) cerebellar brain inhibition (CBI), (3) the nine-hole peg test (9HPT), (4) the 8-m walking time (8MWT), (5) International Cooperative Ataxia Rating Scale (ICARS) score and (6) the Scale for Assessment and Rating of Ataxia (SARA) scores. RESULTS: Seven randomized controlled trials involving 203 patients were included. There were significant improvements in MAS (mean difference [MD] -0.42, 95% confidence interval [CI] -0.76 to -0.08, p = 0.015), CBI (MD -0.35%, 95% CI -0.42 to -0.28, p < 0.001), 8MWT (MD -1.88 s, 95% CI -3.26 to -0.49, p = 0.008), ICARS (MD -7.84, 95% CI -11.90 to -3.78, p < 0.001) and SARA (MD -3.01, 95% CI -4.74 to -1.28, p < 0.001). There was almost no heterogeneity across all outcomes except for CBI (I2  = 79%). No significant changes in the 9HPT were observed comparing NES to a sham procedure (MD -3.52 s, 95% CI -9.15 to 2.10, p = 0.220). Most included studies were at low risk of bias, and no severe adverse effects were reported. CONCLUSION: It was demonstrated that NES is an effective treatment for improving coordination and balance and increased exercise capacity in patients with ataxia and spasticity. There was also a significant modulation of CBI in ataxic patients.