Effects of Repetitive Transcranial Magnetic Stimulation on Cerebellar Metabolism in Patients With Spinocerebellar Ataxia Type 3

Effects of Non-Invasive Brain Stimulation for Degenerative Cerebellar Ataxia: A Systematic Review and Meta-Analysis

BACKGROUND

This systematic review and meta-analysis aimed to assess the effectiveness of non-invasive brain stimulation (NIBS), including repetitive transcranial magnetic stimulation (rTMS) and transcranial electrical stimulation (tES), as a neurological intervention for degenerative cerebellar ataxia (DCA) based on preregistration (PROSPERO: CRD42023379192).

OBJECTIVE

We aimed to explore clinical outcomes and examine the parameters associated with NIBS efficacy in DCA patients.

METHODS

The PubMed, Cochrane Library, CHINAL, and PEDro databases were searched for relevant randomized controlled trials (RCTs). Data extraction, quality assessment, and heterogeneity analyses were conducted; the Grading, Recommendations, Assessment, Development, and Evaluation was used to assess the quality of evidence and a meta-analysis was performed.

RESULTS

Seventeen RCTs that included 661 patients on the scale for assessment and rating of ataxia (SARA) and 606 patients on the International Cooperative Ataxia Rating Scale (ICARS) were included. These RCTs showed a serious risk of bias (RoB) and low certainty of evidence for both outcomes. NIBS significantly reduced SARA (MD = -2.49, [95% confidence interval: -3.34, -1.64]) and ICARS (-5.27 [-7.06, -3.47]); the subgroup analysis showed significant effects: rTMS and tES reduced both outcomes. However, there were no significant differences in the effects of rTMS and tES. Additional subgroup analysis indicated the impact of rTMS frequency and the total number of tES sessions on ataxia.

CONCLUSION

Non-invasive brain stimulation may reduce ataxia in DCA patients, but the estimated effect size may change in future studies because the RoB was serious and the certainty of evidence was low, and the heterogeneity was high. To establish evidence for selecting NIBS methods and parameters, continued high-quality RCTs are required.

Efficacy and Safety of Repetitive Transcranial Magnetic Stimulation in Spinocerebellar Ataxia Type 3: a Systematic Review and Meta‑analysis of Randomized Controlled Trials

Therapeutic alternatives for spinocerebellar ataxia type 3 (SCA3) are limited. Repetitive transcranial magnetic stimulation (rTMS) as a potential intervention has drawn heightened interest because of its ease of implementation, cost-effectiveness, and safety profile. We conducted a systematic review and meta-analysis to evaluate the efficacy of rTMS in the treatment of SCA3. We systematically searched databases-PubMed, Embase, the Cochrane Library, and Springer-for randomized controlled trials (RCTs) investigating the use of rTMS in the treatment of SCA3. Major efficacy outcomes were assessed, including International Cooperative Ataxia Rating Scale (ICARS) scores, Scale for the Assessment and Rating of Ataxia (SARA) scores, and ICARS subscale scores. Six randomized controlled trials involving 175 patients were included in the analysis. The meta-analysis results indicated statistically significant increases in ICARS (mean difference (MD) =  - 3.88, 95% confidence interval (CI) =  - 7.46 to - 0.30; p = 0.03) and SARA (MD of - 1.59, 95% CI - 2.99 to - 0.19; p = 0.03) scores. No significant heterogeneity was observed across all outcomes (I2 = 0%). Dynamic function within the ICARS scale markedly improved with rTMS (MD =  - 2.19, 95% CI =  - 3.82 to - 0.55; p = 0.009). The majority of the included studies exhibited a low risk of bias, and no severe adverse reactions were noted. Our meta-analysis, consisting of six randomized controlled trials with 175 participants, suggests that rTMS exhibits efficacy in alleviating both ataxic symptoms and certain aspects of motor function in SCA3.

Effects of Non-invasive Brain Stimulation on Hereditary Ataxia: a Systematic Review and Meta-analysis

Numerous studies have demonstrated the potential of non-invasive brain stimulation (NIBS) techniques as a viable treatment option for cerebellar ataxia. However, there is a notable dearth of research investigating the efficacy of NIBS specifically for hereditary ataxia (HA), a distinct subgroup within the broader category of cerebellar ataxia. This study aims to conduct a comprehensive systematic review and meta-analysis in order to assess the efficacy of various NIBS methods for the treatment of HA. A thorough review of the literature was conducted, encompassing both English and Chinese articles, across eight electrical databases. The focus was on original articles investigating the therapeutic effectiveness of non-invasive brain stimulation for hereditary ataxia, with a publication date prior to March 2023. Subsequently, a meta-analysis was performed specifically on randomized controlled trials (RCTs) that fulfilled the eligibility criteria, taking into account the various modalities of non-invasive brain stimulation. A meta-analysis was conducted, comprising five RCTs, which utilized the Scale for the Assessment and Rating of Ataxia (SARA) as the outcome measure to evaluate the effects of transcranial magnetic stimulation (TMS). The findings revealed a statistically significant mean decrease of 1.77 in the total SARA score following repetitive TMS (rTMS) (p=0.006). Subgroup analysis based on frequency demonstrated a mean decrease of 1.61 in the total SARA score after high-frequency rTMS (p=0.05), while no improvement effects were observed after low-frequency rTMS (p=0.48). Another meta-analysis was performed on three studies, utilizing ICARS scores, to assess the impact of rTMS. The results indicated that there were no statistically significant differences in pooled ICARS scores between the rTMS group and the sham group (MD=0.51, 95%CI: -5.38 to 6.39; p=0.87). These findings align with the pooled results of two studies that evaluated alterations in post-intervention BBS scores (MD=0.74, 95%CI: -5.48 to 6.95; p=0.82). Despite the limited number of studies available, this systematic review and meta-analysis have revealed promising potential benefits of rTMS for hereditary ataxia. However, it is strongly recommended that further high-quality investigations be conducted in this area. Furthermore, the significance of standardized protocols for NIBS in future studies was also emphasized.

Effects of cerebellar repetitive transcranial magnetic stimulation plus physiotherapy in spinocerebellar ataxias - A randomized clinical trial

BACKGROUND

In absence of drug therapy options, standard treatment for spinocerebellar ataxia consists of symptomatic physiotherapy and speech therapy. New therapeutic options are urgently needed. Transcranial magnetic stimulation is a promising therapeutic option, but applicability is limited by lengthy duration of stimulation protocols.

METHODS

In this randomized sham controlled clinical trial, patients were assigned to verum (n = 15) or sham (n = 18) cerebellar transcranial magnetic stimulation. To yield best possible treatment effects, both intervention groups received intensified physiotherapy for the duration of the study.

RESULTS

Ataxia severity was reduced by 1.6 points on the Scale for assessment and Rating of Ataxia among patients in the verum group (p < 0.001). Clinical improvement was significantly larger in the verum group, compared to the sham group (p < 0.01). The treatment effect was mainly carried by improved appendicular coordination. Patients in the verum group also significantly improved in the 8 Meter Walk Test (p < 0.05) and PATA rate (p < 0.01).

CONCLUSIONS

Cerebellar rTMS ameliorates ataxia severity in patient with spinocerebellar ataxia. Condensing treatment duration to only 5 days without reduction of treatment effects facilitates applicability and therefore broadens availability to larger patient populations.

Effect of Regional Brain Activity Following Repeat Transcranial Magnetic Stimulation in SCA3: A Secondary Analysis of a Randomized Clinical Trial

Repetitive transcranial magnetic stimulation (rTMS), a noninvasive neuroregulatory technique used to treat neurodegenerative diseases, holds promise for spinocerebellar ataxia type 3 (SCA3) treatment, although its efficacy and mechanisms remain unclear. This study aims to observe the short-term impact of cerebellar rTMS on motor function in SCA3 patients and utilize resting-state functional magnetic resonance imaging (RS-fMRI) to assess potential therapeutic mechanisms. Twenty-two SCA3 patients were randomly assigned to receive actual rTMS (AC group, n = 11, three men and eight women; age 32-55 years) or sham rTMS (SH group, n = 11, three men and eight women; age 26-58 years). Both groups underwent cerebellar rTMS or sham rTMS daily for 15 days. The primary outcome measured was the ICARS scores and parameters for regional brain activity. Compared to baseline, ICARS scores decreased more significantly in the AC group than in the SH group after the 15-day intervention. Imaging indicators revealed increased Amplitude of Low Frequency Fluctuation (ALFF) values in the posterior cerebellar lobe and cerebellar tonsil following AC stimulation. This study suggests that rTMS enhances motor functions in SCA3 patients by modulating the excitability of specific brain regions and associated pathways, reinforcing the potential clinical utility of rTMS in SCA3 treatment. The Chinese Clinical Trial Registry identifier is ChiCTR1800020133.

Effects of Cerebellar Repetitive Transcranial Magnetic Stimulation in the Treatment of Post-Stroke Dysphagia: A Meta-Analysis and Systematic Review of Randomized Controlled Trials

INTRODUCTION

This study aimed to comprehensively evaluate the therapeutic efficacy of cerebellar repetitive transcranial magnetic stimulation (rTMS) in the rehabilitation of post-stroke dysphagia (PSD).

METHODS

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we systematically searched PubMed, Cochrane Library, Embase, and Web of Science to identify relevant randomized controlled trials (RCTs) investigating the application of cerebellar rTMS in the treatment of PSD. Inclusion and exclusion criteria were rigorously applied during the screening process, and pertinent characteristics of the included RCTs were meticulously extracted. The I2 statistic was employed to assess heterogeneity, and meta-analysis was conducted using Stata 17 software. The Cochrane Risk of Bias 2 tool and PEDro scale were utilized to evaluate bias risk and literature quality.

RESULTS

Our analysis encompassed a total of 5 RCTs involving 673 patients with dysphagia who met the inclusion criteria. The findings indicated a significant positive impact of cerebellar rTMS when combined with traditional swallowing exercises on PSD, demonstrating superior efficacy compared to conventional swallowing exercises in isolation. Furthermore, the study revealed no statistically significant differences based on stimulation site (unilateral vs. bilateral cerebellum), stimulation mode (rTMS vs. intermittent theta-burst stimulation), and stimulation frequency (5 Hz vs. 10 Hz).

CONCLUSION

The amalgamation of cerebellar rTMS with conventional swallowing exercises demonstrates notable efficacy, surpassing the outcomes achievable with traditional exercises alone. The sustained effectiveness observed underscores the potential of cerebellar rTMS as an innovative avenue in the field of neurorehabilitation for PSD. This study contributes valuable insights into the prospect of utilizing cerebellar rTMS as an adjunctive therapeutic strategy in the management of PSD, emphasizing its relevance for further exploration and clinical application.

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.

Cognitive impairment associated with cerebellar volume loss in spinocerebellar ataxia type 3

BACKGROUND

Many neuroscience and neurology studies have forced a reconsideration of the traditional motor-related scope of cerebellar function, which has now expanded to include various cognitive functions. Spinocerebellar ataxia type 3 (SCA3; the most common hereditary ataxia) is neuropathologically characterized by cerebellar atrophy and frequently presents with cognitive impairment.

OBJECTIVE

To characterize cognitive impairment in SCA3 and investigate the cerebellum-cognition associations.

METHODS

This prospective, cross-sectional cohort study recruited 126 SCA3 patients and 41 healthy control individuals (HCs). Participants underwent a brain 3D T1-weighted images as well as neuropsychological tests. Voxel-based morphometry (VBM) and region of interest (ROI) approaches were performed on the 3D T1-weighted images. CERES was used to automatically segment cerebellums. Patients were grouped into cognitively impaired (CI) and cognitively preserved (CP), and clinical and MRI parameters were compared. Multivariable regression models were fitted to examine associations between cerebellar microstructural alterations and cognitive domain impairments.

RESULTS

Compared to HCs, SCA3 patients showed cognitive domain impairments in information processing speed, verbal memory, executive function, and visuospatial perception. Between CI and CP subgroups, the CI subgroup was older and had lower education, as well as higher severity scores. VBM and ROI analyses revealed volume loss in cerebellar bilateral lobule VI, right lobule Crus I, and right lobule IV of the CI subgroup, and all these cerebellar lobules were associated with the above cognitive domain impairments.

CONCLUSIONS

Our findings demonstrate the multiple cognitive domain impairments in SCA3 patients and indicate the responsible cerebellar lobules for the impaired cognitive domain(s).

Efficacy and Safety of Repetitive Transcranial Magnetic Stimulation in Cerebellar Ataxia: a Systematic Review and Meta-analysis

Cerebellar ataxia(CA) is defined as a degenerative disease of the nervous system. Repetitive transcranial magnetic stimulation (rTMS) has been a promising treatment for neurological and psychiatric diseases. Hence, to find out whether cerebellar rTMS impacts CA as a potential therapy, we performed a systematic review and meta-analysis. Qualified studies through a systematic search were retrieved for randomized controlled trials (RCTs) using acknowledged databases. Review Manager 5.4 software was employed to synthesize the data. A total of seven studies were identified as eligible and included in the quantitative review. Comparing real and sham-rTMS interventions, the utilization of rTMS on cerebellum improved the scale for the assessment and rating of ataxia (SARA) (SMD - 0.87, 95% CI - 1.41 to - 0.34; P = 0.001; I2 = 62%), the International Cooperative Ataxia Rating Scale (ICARS) (SMD - 1.06, 95% CI - 1.47 to - 0.64; P < 0.00001; I2 = 0%) and Berg balance Scale (BBS) (SMD 0.76, 95% CI 0.33 to 1.19; P = 0.0005; I2 = 39%). The subgroup analysis demonstrated high-frequency of rTMS had a positive effect (SMD - 1.28, 95% CI - 1.82 to - 0.74; P < 0.00001; I2 = 0%). For the safety, the incidence of adverse events between the two groups was not significantly different (OR 1.73, 95% CI 0.55 to 5.46; P = 0.35; I2 = 0%). In conclusion, this meta-analysis provided limited evidence, suggesting a possible strategy that rTMS over the cerebellum could be a viable therapy for symptoms associated with CA. Besides, rTMS intervention was well-attended and did not result in unanticipated negative effects.

Feasibility of a randomized, sham-controlled pilot study for accelerated rTMS-treatment of the cerebellum plus physiotherapy in CANVAS patients

BACKGROUND

Cerebellar ataxia, neuropathy and bilateral vestibular areflexia (CANVAS) is a rare neurodegenerative disease affecting the cerebellum, the peripheral nervous system and the vestibular system. Due to the lack of approved drugs, therapy comprises physiotherapy and speech therapy. Transcranial magnetic stimulation is a promising non-invasive therapeutic option to complement classical symptomatic therapies.

OBJECTIVE

To test feasibility of the combination of transcranial magnetic stimulation using an accelerated protocol and standard symptomatic therapy in patients with CANVAS.

METHODS

Eight patients with genetically confirmed CANVAS were assigned to either verum or sham cerebellar transcranial magnetic stimulation using an accelerated protocol. Treatment duration was limited to 5 days. Additionally, patients in both groups received symptomatic therapy (speech and physiotherapy) for the duration of the study.

RESULTS

All patients completed the stimulation protocol. Adverse events were rare. Ataxia severity improved in the verum group only.

CONCLUSION

The combination of transcranial magnetic stimulation and classic symptomatic therapy is feasible in a neuro-rehabilitation setting and potentially ameliorates ataxia severity.

Repetitive transcranial magnetic stimulation for cerebellar ataxia: a systematic review and meta-analysis

Background

Repetitive transcranial magnetic stimulation, a non-invasive brain stimulation technique, can manage cerebellar ataxia (CA) by suppressing cerebral cortical excitability. Hence, this study aimed to summarize the efficacy and safety of rTMS for CA patients by meta-analysis.

Methods

The PubMed, Embase, Web of Science, and Cochrane Library databases were searched for eligible studies published till 20 May 2023. Weighted mean difference (MD) and 95% confidence intervals (CIs) were used to assess the effect of rTMS treatment. Additionally, the quality of the included studies and the risk of bias were evaluated using the Physiotherapy Evidence Database (PEDro) scale.

Results

Overall, eight studies involving 278 CA patients were included in this meta-analysis. rTMS could significantly improve the Scale for the Assessment and Rating of Ataxia (SARA) (MD: -2.00; 95% CI: -3.97 to -0.02, p = 0.05), International Cooperative Ataxia Rating Scale (ICARS) (MD: -3.96; 95% CI: -5.51 to -2.40, p < 0.00001), Timed Up-and-Go test (TUG) (MD: -1.54; 95% CI: -2.24 to -0.84, p < 0.0001), 10-m walk test (10 MWT) (MD_{10-m steps}: -2.44; 95% CI: -4.14 to -0.73, p = 0.005), and Berg Balance Scale (BBS) (MD: 2.59; 95% CI: 1.15-4.03, p = 0.0004) as compared to sham stimulation. Active rTMS was not significantly different from sham rTMS in changing the duration (MD_{10-m time}: -1.29; 95% CI: -7.98 to 5.41, p = 0.71). No severe adverse events were observed in both sham stimulation and active rTMS groups.

Conclusion

This meta-analysis provides limited evidence that rTMS may be beneficial in treating CA patients. However, these findings should be treated with caution due to the limitations of the smaller sample size and the inconsistent approach and target of rTMS treatment. Therefore, more large-scale RCTs are required to further validate our analytical findings.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=295726, identifier: CRD42022295726.

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.

Effects of transcranial magnetic stimulation on cerebellar ataxia: A systematic review and meta-analysis

Objective

To determine the effectiveness of transcranial magnetic stimulation in improving cerebellar ataxia.

Data sources

PubMed, EMBASE, the Cochrane Library, Springer, Science Direct, the China National Knowledge Infrastructure (CNKI) and the China Science and Technology Journal Database (VIP) were searched until 2022.

Review methods

Trials with transcranial magnetic stimulation on the effects on cerebellar ataxia were included, and the effect size was evaluated using the standardized mean difference (SMD) or mean difference (MD) and a 95% confidence interval (CI).

Results

Eight studies comprising 272 participants, published between 2014 and 2022, were included. The results revealed that the effect of TMS on patients with cerebellar ataxia as assessed by the International Cooperative Ataxia Rating Scale (ICRAS), the Scale for the Assessment and Rating of Ataxia (SARA), the Berg Balance Scale (BBS), and the Timed Up and Go (TUG) test was statistically significant (P < 0.01) with low heterogeneity among the studies (I² = 4, 27, 0, and 0% respectively).

Conclusion

The effects of transcranial magnetic stimulation in improving cerebellar ataxia in the affected patients are significant. TMS targeting the cerebellar structures can induce changes in the excitability of the cerebellar-thalamus-cortical pathways; thus, it is necessary to carry out large-scale research with good design and high quality in the future.

Pharmacotherapy for the management of the symptoms of Machado-Joseph Disease

INTRODUCTION

Machado-Joseph disease or spinocerebellar ataxia type 3 (SCA3/MJD) is the leading cause of autosomal dominant ataxia worldwide. This is a slowly progressive, but very disabling disorder. Ataxia is the main clinical feature, but additional motor and non-motor manifestations may be found. Many of these manifestations are amenable to pharmacological treatments, which may impact the quality of life of affected subjects.

AREAS COVERED

Authors review available literature on both disease-modifying and symptomatic pharmacological therapies for SCA3/MJD. Discussion is stratified into motor (ataxic and non-ataxic syndromes) and non-motor manifestations. Ongoing clinical trials and future perspectives are also discussed in the manuscript.

EXPERT OPINION

Symptomatic treatment is the mainstay of clinical care and should be tailored for each patient with SCA3/MJD. Management of ataxia is still a challenging task, but relief (at least partial) of dystonia, pain/cramps, fatigue, and sleep disorders is an achievable goal for many patients. Even though there are no disease-modifying treatments so far, recent advances in understanding the biology of disease and international collaborations of clinical researchers are now paving the way for a new era where more clinical trials will be available for this devastating disorder.

Repetitive transcranial magnetic stimulation (rTMS) as a therapeutic option in paraneoplastic cerebellar ataxia - a case report

Paraneoplastic cerebellar ataxia is a paraneoplastic neurological syndrome (PNS) that can be the first clinical manifestation of underlying cancer. It is usually associated with onco-neuronal antibodies and has no other specific paraclinical feature. After the surgical and oncologic treatment of the primary cancer, the remaining neurological symptoms have limited therapeutic options. We describe a case of severe ataxia as the primary manifestation of ovarian cancer, with a significant clinical and paraclinical improvement of the neurological symptoms after 20 sessions of rTMS intervention.