Reliability and validity of the International Cooperative Ataxia Rating Scale: A study in 156 spinocerebellar ataxia patients

[Scale for the assessment and rating of ataxia (SARA): translation and cultural adaptation to German-speaking areas]

BACKGROUND/OBJECTIVE

The scale for the assessment and rating of ataxia (SARA) is a feasible assessment for the classification and evaluation of therapeutic interventions. In order to provide access to the SARA in German, the aim of this work was to translate the SARA into German and to adapt it according to international guidelines for German-speaking countries.

METHOD

The process involved six steps. The comprehensibility of the scale was assessed using interviews with potential users.

RESULTS

A total of nine physiotherapists and six physicians working in various clinical settings were interviewed, seven of them worked in Germany and four each in Austria and Switzerland. The interviews led to a refined version of the translation. The comprehensibility testing revealed no country-specific differences.

CONCLUSION

A German version of the SARA authorized by the co-author of the original publication, is now available. The results provide methodological insights into the translation process of observation-based standardized assessments.

Consensus framework for conducting phase I/II clinical trials for children, adolescents, and young adults with pediatric low-grade glioma: Guidelines established by the International Pediatric Low-Grade Glioma Coalition Clinical Trial Working Group

Within the last few decades, we have witnessed tremendous advancements in the study of pediatric low-grade gliomas (pLGG), leading to a much-improved understanding of their molecular underpinnings. Consequently, we have achieved successful milestones in developing and implementing targeted therapeutic agents for treating these tumors. However, the community continues to face many unknowns when it comes to the most effective clinical implementation of these novel targeted inhibitors or combinations thereof. Questions encompassing optimal dosing strategies, treatment duration, methods for assessing clinical efficacy, and the identification of predictive biomarkers remain unresolved. Here, we offer the consensus of the international pLGG coalition (iPLGGc) clinical trial working group on these important topics and comment on clinical trial design and endpoint rationale. Throughout, we seek to standardize the global approach to early clinical trials (phase I and II) for pLGG, leading to more consistently interpretable results as well as enhancing the pace of novel therapy development and encouraging an increased focus on functional endpoints as well and quality of life for children faced with this disease.

French Translation and Cross-cultural Adaptation of the Scale for the Assessment and Rating of Ataxia

The Scale for the Assessment and Rating of Ataxia (SARA) is a widely used scale for assessing the severity of ataxia in clinics, natural history studies, and treatment trials worldwide. However, no French translation with validated cross-cultural adaptation is available. This study aimed to translate and adapt the SARA into French. The translation process was conducted according to the ISPOR guidelines for the translation and cultural adaptation process for patient-reported outcomes. A total of five translators, an expert committee, and two physiotherapists took part in the process to assess and ensure comprehension and language equivalences of the final French version. A few misinterpretations were pointed out during the translation process and were changed accordingly by the translation team. The French version of the SARA is ready to be used in clinical and research settings with French-speaking populations living with ataxia.

Home Aerobic Training for Cerebellar Degenerative Diseases: a Randomized Controlled Trial

Balance training has shown some benefits in cerebellar ataxia whereas the effects of aerobic training are relatively unknown. To determine whether a phase III trial comparing home aerobic to balance training in ambulatory patients with cerebellar ataxia is warranted, we conducted a single-center, assessor-blinded, randomized controlled trial. Nineteen subjects were randomized to aerobic training and 17 subjects to balance training. The primary outcome was improvement in ataxia as measured by the Scale for the Assessment and Rating of Ataxia (SARA). Secondary outcomes included safety, training adherence, and balance improvements. There were no differences between groups at baseline. Thirty-one participants completed the trial, and there were no training-related serious adverse events. Compliance to training was over 70%. There was a mean improvement in ataxia symptoms of 1.9 SARA points (SD 1.62) in the aerobic group compared to an improvement of 0.6 points (SD 1.34) in the balance group. Although two measures of balance were equivocal between groups, one measure of balance showed greater improvement with balance training compared to aerobic training. In conclusion, this 6-month trial comparing home aerobic versus balance training in cerebellar ataxia had excellent retention and adherence to training. There were no serious adverse events, and training was not interrupted by minor adverse events like falls or back pain. There was a significant improvement in ataxia symptoms with home aerobic training compared to balance training, and a phase III trial is warranted. Clinical trial registration number: NCT03701776 on October 8, 2018.

Ataxias: Hereditary, Acquired, and Reversible Etiologies

A variety of etiologies can cause cerebellar dysfunction, leading to ataxia symptoms. Therefore, the accurate diagnosis of the cause for cerebellar ataxia can be challenging. A step-wise investigation will reveal underlying causes, including nutritional, toxin, immune-mediated, genetic, and degenerative disorders. Recent advances in genetics have identified new genes for both autosomal dominant and autosomal recessive ataxias, and new therapies are on the horizon for targeting specific biological pathways. New diagnostic criteria for degenerative ataxias have been proposed, specifically for multiple system atrophy, which will have a broad impact on the future clinical research in ataxia. In this article, we aim to provide a review focus on symptoms, laboratory testing, neuroimaging, and genetic testing for the diagnosis of cerebellar ataxia causes, with a special emphasis on recent advances. Strategies for the management of cerebellar ataxia is also discussed.

Telerehabilitation versus virtual reality supported task-oriented circuit therapy on upper limbs and trunk functions in patients with multiple sclerosis: A randomized controlled study

INTRODUCTION

The purpose of this study was to investigate the effects of two different technology-supported rehabilitation approaches which are mobile application based telerehabilitation (TR) and virtual reality supported task oriented circuit therapy groups (V-TOCT) on the upper limb (UL), trunk function, and functional activity kinematics in patients with Multiple Sclerosis (PwMS).

METHODS

Thirty-four patients with PwMS were included in this study. The participants were evaluated at baseline and after eight weeks of treatment by an experienced physiotherapist using the Trunk Impairment Scale (TIS), kinetic function sub-parameter of the International Cooperative Ataxia Rating Scale (K-ICARS), ABILHAND, Minnesota Manual Dexterity tests (MMDT), and trunk and UL kinematics using inertial sensors. The participants were randomized into the TR and V-TOCT groups with a 1:1 allocation ratio. All participants received interventions for 1 hour per session, 3 sessions per week, for 8 weeks.

RESULTS

Trunk impairment, ataxia severity, UL, and hand function showed statistically significant improvement in both groups. The functional range of motion (FRoM) of shoulder and wrist increased transversal plane and the FRoM of shoulder increased on sagittal plane in V-TOCT. Log Dimensionless Jerk (LDJ) decreased on transversal plane in V-TOCT group. The FRoM of the trunk joints increased on the coronal plane and the FRoM of the trunk joints increased on the transversal plane in TR. Dynamic balance of the trunk and K-ICARS improved better in V-TOCT than in TR (p < 0,05).

CONCLUSIONS

V-TOCT and TR improved UL function, TIS, and ataxia severity in PwMS. The V-TOCT was more effective than the TR in terms of dynamic trunk control and kinetic function. The clinical results were confirmed using the kinematic metrics of motor control.

Validity and Reliability of the Korean-Translated Version of the International Cooperative Ataxia Rating Scale in Cerebellar Ataxia

OBJECTIVE

The International Cooperative Ataxia Rating Scale (ICARS) is a semiquantitative clinical scale for ataxia that is widely used in numerous countries. The purpose of this study was to investigate the validity and reliability of the Korean-translated version of the ICARS.

METHODS

Eighty-eight patients who presented with cerebellar ataxia were enrolled. We investigated the construct validity using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). We also investigated the internal consistency using Cronbach's α and intrarater and interrater reliability using intraclass correlation coefficients.

RESULTS

The Korean-translated ICARS showed satisfactory construct validity using EFA and CFA. It also revealed good interrater and intrarater reliability and showed acceptable internal consistency. However, subscale 4 for assessing oculomotor disorder showed moderate internal consistency.

CONCLUSION

This is the first report to investigate the validity and reliability of the Korean-translated ICARS. Our results showed excellent construct and convergent validity. The reliability is also acceptable.

A rehabilitation program to increase balance and mobility in ataxia of Charlevoix-Saguenay: An exploratory study

Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is characterized by balance impairment and mobility limitations, which both increase the risk of falling. The objective of this study was to explore the effects of a rehabilitation program aimed at increasing trunk and lower limb motor control on balance and walking abilities, and accomplishment of activities of daily living. In this exploratory study, a group-supervised rehabilitation program was performed three times a week for 8 weeks (two sessions at a rehabilitation gym and one pool session). Outcome measures included the Ottawa Sitting Scale, Berg Balance Scale, modified Activities-specific Balance Confidence Scale, 30-Second Chair Stand Test, 10-Meter Walk Test, Barthel Index, and Scale for the Assessment and Rating of Ataxia. Significant improvements in balance, trunk control, maximal and self-selected walking speed difference, ataxia severity and accomplishment of specific activities of daily living were noted for the whole group at the end of the program. At the individual level, all participants improved beyond the standard error of measurement in at least two outcome measures. Also, most participants reported many perceived improvements related to balance, posture and functional mobility. This study provides encouraging results on the effects of a rehabilitation program for ambulatory people with ARSACS. Group intervention could have a positive impact on their daily lives and improve the health care service offered to this population. Future studies with larger sample sizes including control groups and other forms of ataxia are necessary to validate our results to generalize them.

Effect of speech therapy on quality of life in patients with spinocerebelar ataxia type 3

BACKGROUND

Individuals with spinocerebellar ataxia type 3 (SCA3) present communication and swallowing disorders, and consequent deterioration in quality of life (QOL).

OBJECTIVE

To evaluate the impact of a speech therapy rehabilitation program on the QOL of patients with SCA3.

METHODS

All participants were randomly assigned to two groups, an intervention group receiving speech therapy (STG) and a control group (CG). The International Cooperative Ataxia Rating Scale scores were 32.4 ± 20.2, and the Scale for the Assessment and Rating of Ataxia scores were 11.8 ± 8.0. The intervention consisted of a 12-session speech therapy rehabilitation program with oral, pharyngeal, and laryngeal strengthening exercises-the so-called ATAXIA-Myofunctional Orofacial and Vocal Therapy (A-MOVT). They all were submitted to pre- and postintervention evaluations using the World Health Organization's Quality of Life (WHOQOL-BREF) assessment, as well as the Living with Dysarthria (LwD), Quality of Life in Swallowing Disorders (SWAL-QOL), and Food Assessment Tool (EAT-10).

RESULTS

The study sample consisted of 48 patients with SCA3 (STG = 25; CG = 23), mean age was 47.1 ± 11.4 years; mean age at symptom onset was 36.9 ± 11.3 years; disease duration was 11.9 ± 13.3 years. After the 3-month intervention, there were significant changes in the QOL in the STG compared with the CG, when assessed by the LwD (179.12 ± 62.55 vs. 129.88 ± 51.42, p < 0.001), SWAL-QOL (869.43 ± 153.63 vs. 911.60 ± 130.90, p = 0.010), and EAT-10 (5.16 ± 7.55 vs. 2.08 ± 3.85, p = 0.018).

CONCLUSIONS

Patients with SCA3 should receive continuous speech therapy as part of the A-MOVT program, because therapy helps to improve difficulty swallowing and dysarthria.

Ataxia Rating Scales: Content Analysis by Linking to the International Classification of Functioning, Disability and Health

Ataxia management is mainly based on rehabilitation, symptomatic management, and functional improvement. Therefore, it is important to comprehensively assess ataxic symptoms and their impact on function. Recently, the movement disorders society recommended four generic ataxia rating scales: scale for assessment and rating of ataxia (SARA), international cooperative ataxia rating scales, Friedreich's ataxia rating scale (FARS), and unified multiple system atrophy rating scale (UMSARS). The aim of the study was to analyze and compare the content of the recommended ataxia rating scales by linking them to the international classification of functioning, disability and health (ICF). A total of 125 meaningful concepts from 93 items of the four included scales were linked to 57 different ICF categories. The ICF categories were distributed in body structure (n = 8), body function (n = 26), activity and participation (n = 20), and environmental factors (n = 3) components. UMSARS and FARS were the only ones that have addressed the body structure or environmental factors component. The content analysis of ataxia rating scales would help clinicians and researchers select the most appropriate scale and understand ataxic symptoms and their impact on function. It seems that SARA is the optimal scale for rapid assessment of ataxia or in busy clinical settings. UMSARS or FARS are more appropriate for the investigating the impact of ataxia on overall health, and monitoring ataxia progression and disability.

Clinical Motor Coordination Tests in Adult Neurology: A Scoping Review

Purpose: This scoping review aimed to identify which clinical tests are used to assess upper limb, lower limb, and trunk motor coordination, and their metric and measurement properties for adult neurological populations. Method: MEDLINE (1946-) and EMBASE (1996-) databases were searched using keywords such as movement quality, motor performance, motor coordination, assessment, and psychometrics. Data regarding the body part assessed, neurological condition, psychometric properties, and scored metrics of spatial and/or temporal coordination were independently extracted by two reviewers. Alternate versions of some tests such as the Finger-to-Nose Test were included. Results: Fifty-one included articles yielded 2 tests measuring spatial coordination, 7 tests measuring temporal coordination, and 10 tests measuring both. Scoring metrics and measurement properties differed between tests, with a majority of tests having good-to-excellent measurement properties. Conclusions: The metrics of motor coordination scored by current tests vary. Since tests do not assess functional task performance, the onus falls on clinicians to infer the connection between coordination impairments and functional deficits. Clinical practice would benefit from the development of a battery of tests that assesses the metrics of coordination related to functional performance.

Objective Assessment of Upper-Extremity Motor Functions in Spinocerebellar Ataxia Using Wearable Sensors

The study presents a novel approach to objectively assessing the upper-extremity motor symptoms in spinocerebellar ataxia (SCA) using data collected via a wearable sensor worn on the patient's wrist during upper-extremity tasks associated with the Assessment and Rating of Ataxia (SARA). First, we developed an algorithm for detecting/extracting the cycles of the finger-to-nose test (FNT). We extracted multiple features from the detected cycles and identified features and parameters correlated with the SARA scores. Additionally, we developed models to predict the severity of symptoms based on the FNT. The proposed technique was validated on a dataset comprising the seventeen (n = 17) participants' assessments. The cycle detection technique showed an accuracy of 97.6% in a Bland-Altman analysis and a 94% accuracy (F1-score of 0.93) in predicting the severity of the FNT. Furthermore, the dependency of the upper-extremity tests was investigated through statistical analysis, and the results confirm dependency and potential redundancies in the upper-extremity SARA assessments. Our findings pave the way to enhance the utility of objective measures of SCA assessments. The proposed wearable-based platform has the potential to eliminate subjectivity and inter-rater variabilities in assessing ataxia.

Quantitative evaluation of upper limb ataxia in spinocerebellar ataxias

Objective

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.

Methods

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.

Results

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.

Interpretation

Our study demonstrated that the distortion index is a reliable functional marker that is sensitive to longitudinal change in patients with SCA.

Rehabilitation in patients with cerebellar ataxias

ABSTRACT 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.

Detection of ataxia with hybrid convolutional neural network using static plantar pressure distribution model in patients with multiple sclerosis

OBJECTIVE

In this study, it is aimed to detect ataxia for Persons with Multiple Sclerosis (PwMS) through a deep learning-based approach using an image dataset containing static plantar pressure distribution. Here, an alternative and objective method will be proposed to assist physicians who diagnose PwMS in the early stages.

METHODS

A total of 406 static bipedal pressure distribution image data for 43 ataxic PwMS and 62 healthy individuals were used in the study. After preprocessing, these images were given as input to pre-trained deep learning models such as VGG16, VGG19, ResNet, DenseNet, MobileNet, and NasNetMobile. The data of each model is utilized to generate its feature vectors. Finally, feature vectors obtained from static pressure distribution images were classified by SVM (Support Vector Machine), K-NN (K-Nearest Neighbors), and ANN (Artificial Neural Network). In addition, a cross-validation method was used to examine the validity of the classifier.

RESULTS

The performance of the proposed models was evaluated with accuracy, sensitivity, specificity, and F1-measure criteria. The VGG19-SVM hybrid model showed the best performance with 95.12% acc, 94.91% sen, 95.31% spe, and 94.44% F1.

CONCLUSIONS

In this study, a specific and sensitive automatic test evaluation system was proposed for Ataxic syndromes using digital images to observe the motor skills of the subjects. Comparative results show that the proposed method can be applied in practice for ataxia that is clinically difficult to detect or not yet symptomatic. It can be defined using only static plantar pressure distribution in the early stage and it can be recommended as an assistant system to physicians in clinical practice.

Toward allele-specific targeting therapy and pharmacodynamic marker for spinocerebellar ataxia type 3

Spinocerebellar ataxia type 3 (SCA3), caused by a CAG repeat expansion in the ataxin-3 gene (ATXN3), is characterized by neuronal polyglutamine (polyQ) ATXN3 protein aggregates. Although there is no cure for SCA3, gene-silencing approaches to reduce toxic polyQ ATXN3 showed promise in preclinical models. However, a major limitation in translating putative treatments for this rare disease to the clinic is the lack of pharmacodynamic markers for use in clinical trials. Here, we developed an immunoassay that readily detects polyQ ATXN3 proteins in human biological fluids and discriminates patients with SCA3 from healthy controls and individuals with other ataxias. We show that polyQ ATXN3 serves as a marker of target engagement in human fibroblasts, which may bode well for its use in clinical trials. Last, we identified a single-nucleotide polymorphism that strongly associates with the expanded allele, thus providing an exciting drug target to abrogate detrimental events initiated by mutant ATXN3. Gene-silencing strategies for several repeat diseases are well under way, and our results are expected to improve clinical trial preparedness for SCA3 therapies.

Volumetric MRI Changes in Spinocerebellar Ataxia (SCA3 and SCA10) Patients

Spinocerebellar ataxias type 3 (SCA3) and type 10 (SCA10) are the most prevalent in southern Brazil. To analyze the relationships between volumetric MRI changes and clinical and genetic findings in SCA3 and SCA10 patients. All patients in the study had a confirmed genetic diagnosis. Demographic data, ataxia severity (SARA score), and the size of the expanded alleles were evaluated. Nineteen SCA3 and 18 SCA10 patients were selected and compared with a similar number of healthy controls. Patient and control groups underwent the same MRI protocol. The standard FreeSurfer pipeline was used for the morphometric data. Our results show more affected brain structures (volume reductions) in SCA3 patients than in SCA10 patients (15 vs. 5 structures). Volume reductions in brain structures were also greater in the former. The main areas with significant volumetric reductions in the former were the cerebellum, basal ganglia, brain stem, and diencephalon, whereas in the latter, significant volume reductions were observed in the cerebellum and pallidum. While SARA scores and disease duration were more correlated with volume reduction in SCA10, in SCA3, the expansion length (CAGn) correlated positively with cerebellar WM, thalamus, brain stem, and total GM volumes. There was no correlation between expansion length (ATTCTn) and neuroimaging findings in SCA10. Neuroimaging results differed significantly between SCA3 and SCA10 patients and were compatible with the differences in clinical presentation, disease progression, and molecular findings.

Factors Affecting Hypertensive Treatment Adherence: Development and Preliminary Validation of a New Scale

Design

A sequential exploratory mixed method study was used.

Methods

After item generation using a qualitative study and literature review, the psychometric properties of the scale were evaluated. Face, content, and construct validity, Cronbach's alpha, and test-retest reliability were used to validate the scales.

Results

Data analysis showed that the scale had acceptable face and content validity. The scale had excellent stability (intraclass correlation = 0.89) and good acceptability of internal consistency (α = 0.71). The exploratory factor analysis showed that the scale consisted of five subscales which were meaningful.

Conclusion

Psychometric properties of the scale achieved the standard level, and it was sufficient to recommend for general use in future measures of caring in nursing.

Can the ARAT Be Used to Measure Arm Function in People With Cerebellar Ataxia?

OBJECTIVE

For people with ataxia, there are validated outcome measures to address body function and structure (BFS) impairments and participation; however, no outcome measure exists for upper extremity (UE) activity level in this population. The purpose of this study was to determine whether the action research arm test (ARAT), a measure of UE activity validated for other neurological conditions, might be a useful outcome measure for capturing UE activity limitations in ataxia.

METHODS

A total of 22 participants with ataxia were evaluated to assess construct validity of the ARAT; 19 of the participants were included in the interrater reliability assessment. Participants received a neurologic examination and completed a battery of outcome measures, including the ARAT. ARAT performance was video recorded and scored by 4 additional raters.

RESULTS

For construct validity, Spearman rho showed a significant moderate relationship between the ARAT and BSF outcome measures. A small, nonsignificant relationship was noted for the ARAT and the participation measure. For interrater reliability, Spearman rho showed a large, significant relationship among all raters for the ARAT (range = .87-.94). High reliability was demonstrated using the intraclass correlation coefficient ([2,1] = .97).

CONCLUSION

The ARAT is moderately correlated with ataxia BFS outcome measures, but not with participation scores. The ARAT is a measure of UE activity, which is different from BFS and participation outcome measures. The ARAT was identified to have strong interrater reliability among raters with varying amounts of experience administering the ARAT. Thus, for the ataxic population, the ARAT may be useful for assessing UE activity limitations.

IMPACT

Ataxia can negatively affect reaching tasks; therefore, it is important to assess UE activity level in people with ataxia. Until this study, no outcome measure had been identified for this purpose.

LAY SUMMARY

People with ataxia may have difficulty with daily tasks that require reaching. The ARAT is an outcome measure that clinicians can use to assess UE activity limitations to help design a treatment program.

Selective Procedural Memory Impairment but Preserved Declarative Memory in Spinocerebellar Ataxia Type 3

Spinocerebellar ataxia type 3 (SCA3), also known as Machado-Joseph disease, is an autosomal dominant neurodegenerative disorder that affects mainly the cerebellum and less other brain areas. While the ataxic/motor features of the disease have been well described, the cognitive consequences of the degeneration require additional testing. The aim of this study was to evaluate learning abilities in SCA3. We tested 13 SCA3 patients and 14 age-matched healthy controls, all of Yemenite origin, on a neuropsychological battery of procedural and declarative memory tests. SCA3 patients demonstrated impaired sequence learning on the procedural Serial Reaction Time test (SRTt) but normal learning on the procedural Weather Prediction Probabilistic Classification test (WPPCt). SCA3 patients showed normal learning on the declarative Rey Auditory Verbal Learning test (Rey-AVLt). The correlations between the learning measures of the SRTt, WPPCt, and Rey-AVLt tests in SCA3 and controls separately were not significant. These results imply that the cerebellar degeneration in SCA3 causes selective impairment in procedural sequence learning while the procedural probabilistic learning and declarative memory were mostly preserved. These findings support the assumption that procedural learning is not a homogeneous function and could be dissociated in cerebellar neurodegenerative disease.

Placebo response in degenerative cerebellar ataxias: a descriptive review of randomized, placebo-controlled trials

Placebo response in degenerative cerebellar ataxias (CAs) has never been studied despite the large number of randomized controlled trials (RCTs) that have been conducted. In this descriptive review, we aimed to examine the placebo response in patients with CAs. We performed a literature search on PubMed for RCTs on CAs that were published from 1977 to January 2020 and collected data on the changes from the baseline to the endpoint on various objective ataxia-associated clinical rating scales. We reviewed 56 clinical trials, finally including 35 parallel-group studies and excluding 21 cross-over studies. The included studies were categorized as follows: (1) studies showing significant improvements in one or more ataxia scales in the placebo groups (n = 3); (2) studies reporting individual placebo responders with improvements in one or more ataxia scales in the placebo groups (n = 5)-the overall proportion of placebo responders was 31.9%; (3) studies showing mean changes in the direction of improvement in at least one ataxia scale in the placebo groups, though not statistically significant (n = 19); (4) studies showing no placebo response in any of the ataxia scales in the placebo groups (n = 4); (5) studies where data on the placebo groups were unavailable (n = 9). This review demonstrated the placebo response in patients with CAs on various objective ataxia scales. Our study emphasizes that the placebo response should be considered when designing, analyzing, and interpreting clinical trials and in clinical practice in CA patients.

Assessment of Ataxia Rating Scales and Cerebellar Functional Tests: Critique and Recommendations

BACKGROUND

We assessed the clinimetric properties of ataxia rating scales and functional tests, and made recommendations regarding their use.

METHODS

A systematic literature search was conducted to identify the instruments used to rate ataxia symptoms. The identified rating scales and functional ability tests were reviewed and ranked by the panel as "recommended," "suggested," or "listed" for the assessment of patients with discrete cerebellar disorders, using previously established criteria.

RESULTS

We reviewed 14 instruments (9 rating scales and 5 functional tests). "Recommended" rating scales for the assessment of symptoms severity were: for Friedreich's ataxia, the Friedreich's Ataxia Rating Scale, the International Cooperative Ataxia Rating Scale (ICARS), and the Scale for the Assessment and Rating of Ataxia (SARA); for spinocerebellar ataxias, ICARS and SARA; for ataxia telangiectasia: ICARS and SARA; for brain tumors, SARA; for congenital disorder of glycosylation-phosphomannomutase-2 deficiency, ICARS; for cerebellar symptoms in multiple sclerosis, ICARS; for cerebellar symptoms in multiple system atrophy: Unified Multiple System Atrophy Rating Scale and ICARS; and for fragile X-associated tremor ataxia syndrome, ICARS. "Recommended" functional tests were: for Friedreich's ataxia, Ataxia Functional Composite Score and Composite Cerebellar Functional Severity Score; and for spinocerebellar ataxias, Ataxia Functional Composite Score, Composite Cerebellar Functional Severity Score, and SCA Functional Index.

CONCLUSIONS

We identified some "recommended" scales and functional tests for the assessment of patients with major hereditary ataxias and other cerebellar disorders. The main limitations of these instruments include the limited assessment of patients in the more severe end of the spectrum and children. Further research in these populations is warranted. © 2020 International Parkinson and Movement Disorder Society.

Cerebellar-cortical function and connectivity during sensorimotor behavior in aging FMR1 gene premutation carriers

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FMR1 premutation carriers show increased variability in motor control.

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Premutation carriers show reduced extrastriate activation during motor behavior.

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Premutation carriers show reduced extrastriate-cerebellar functional connectivity.

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Reduced extrastriate-cerebellar functional connectivity is related to motor issues.

Introduction

Premutation carriers of the FMR1 gene are at risk of developing fragile X-associated tremor/ataxia syndrome (FXTAS), a neurodegenerative disease characterized by motor, cognitive, and psychiatric decline as well as cerebellar and cerebral white matter pathology. Several studies have documented preclinical sensorimotor issues in aging premutation carriers, but the extent to which sensorimotor brain systems are affected and may represent early indicators of atypical neurodegeneration has not been determined.

Materials and methods

Eighteen healthy controls and 16 FMR1 premutation carriers (including five with possible, probable, or definite FXTAS) group-matched on age, sex, and handedness completed a visually guided precision gripping task with their right hand during fMRI. During the test, they used a modified pinch grip to press at 60% of their maximum force against a custom fiber-optic transducer. Participants viewed a horizontal white force bar that moved upward with increased force and downward with decreased force and a static target bar that was red during rest and turned green to cue the participant to begin pressing at the beginning of each trial. Participants were instructed to press so that the white force bar stayed as steady as possible at the level of the green target bar. Trials were 2-sec in duration and alternated with 2-sec rest periods. Five 24-sec blocks consisting of six trials were presented. Participants’ reaction time, the accuracy of their force relative to the target force, and the variability of their force accuracy across trials were examined. BOLD signal change and task-based functional connectivity (FC) were examined during force vs. rest.

Results

Relative to healthy controls, premutation carriers showed increased trial-to-trial variability of force output, though this was specific to younger premutation carriers in our sample. Relative to healthy controls, premutation carriers also showed reduced extrastriate activation during force relative to rest. FC between ipsilateral cerebellar Crus I and extrastriate cortex was reduced in premutation carriers compared to controls. Reduced Crus I-extrastriate FC was related to increased force accuracy variability in premutation carriers. Increased reaction time was associated with more severe clinically rated neurological abnormalities.

Conclusions

Findings of reduced activation in extrastriate cortex and reduced Crus I-extrastriate FC implicate deficient visual feedback processing and reduced cerebellar modulation of corrective motor commands. Our results are consistent with documented cerebellar pathology and visual-spatial processing in FXTAS and pre-symptomatic premutation carriers, and suggest FC alterations of cerebellar-cortical networks during sensorimotor behavior may represent a “prodromal” feature associated with FXTAS degeneration.

Oxygen Cost During Walking in Individuals With Stroke: Hemiparesis Versus Cerebellar Ataxia

Background. Understanding the factors that limit mobility in stroke patients is fundamental for proposing appropriate rehabilitation strategies. A high oxygen cost during walking (Cw) has a strong impact on the community ambulation of hemiparetic patients. The Cw in poststroke cerebellar ataxia is poorly evaluated, unlike hemiparetic gait. Objective. To compare the oxygen cost/self-selected walking speed (S) relationship in stroke individuals with cerebellar ataxia or hemiparetic gait. Methods. Thirty-three subjects were included (14 cerebellar stroke, 19 hemispheric stroke), with stroke confirmed by brain imaging and able to walk without human assistance. We measured Cw using the Metamax3B. The relationship between Cw and self-selected walking speed was modelled by logistic regression and then compared between the cerebellar and hemispheric groups. Results. No significant difference was found between the 2 groups for all characteristics of the population, except motor impairments, spasticity, and ataxia (P < .01). We identified 2 separate Cw/S relationships with different logistic regression equations for the 2 groups. Faster than 0.4 m s⁻¹, Cw was 30.6% to 39.9% higher in patients with cerebellar stroke in comparison with hemispheric stroke individuals. The Cw was correlated with ataxia (r = 0.88; P < .001) in the cerebellar group, whereas there was a correlation with motor impairments (r = −0.61; P < .01), spasticity (r = 0.59; P < .01), and ataxia (r = 0.81; P < .01) in hemispheric stroke individuals. Conclusion. The Cw in poststroke cerebellar ataxia is significantly higher compared with hemiparetic patients at an equivalent walking speed. The impact on community walking needs to be explored in stroke survivors with cerebellar stroke.

Developing a smartphone application, triaxial accelerometer-based, to quantify static and dynamic balance deficits in patients with cerebellar ataxias

BACKGROUND

Cerebellar ataxia is characterized by difficulty in the planning of movement and lack of anticipatory postural adjustments, which can result in deficits of balance. Being able to have quantitative measurements in clinical practice, to detect any improvements on balance resulting from new rehabilitation treatments or experimental drugs is very important.

AIM

The purpose of this study was to develop an application (APP) able to assess static and dynamic balance in patients with cerebellar ataxias (CA). The APP that works by a wearable device (smartphone) placed at the breastbone level and immobilized by an elastic band, measures the body sway by means of a triaxial accelerometer.

METHODS

We investigated 40 CA patients and 80 healthy subjects. All patients were clinically evaluated using the "Berg Balance Scale" (BBS) and the "Scale for the Assessment and Rating of Ataxia" (SARA). Balance impairment was quantitatively assessed using a validated static balance evaluating systems, i.e., Techno-body Pro-Kin footboard. All participants underwent static and dynamic balance assessments using the new APP.

RESULTS

We observed a strong correlation between the APP measurements and the score obtained with the BBS, SARA, and Pro-Kin footboard. The intra-rater reliability and the test-retest reliability of the APP measurements, estimated by intraclass correlation coefficient, were excellent. The standard error of measurement and the minimal detectable change were small. No learning effect was observed.

CONCLUSIONS

We can state that the APP is an easy, reliable, and valid evaluating system to quantify the trunk sway in a static position and during the gait.

Precision Sensorimotor Control in Aging FMR1 Gene Premutation Carriers

BACKGROUND

Individuals with premutation alleles of the FMR1 gene are at risk of developing fragile X-associated tremor/ataxia syndrome (FXTAS), a neurodegenerative condition affecting sensorimotor function. Information on quantitative symptom traits associated with aging in premutation carriers is needed to clarify neurodegenerative processes contributing to FXTAS.

MATERIALS AND METHODS

26 FMR1 premutation carriers ages 44-77 years and 31 age-matched healthy controls completed rapid (2 s) and sustained (8 s) visually guided precision gripping tasks. Individuals pressed at multiple force levels to determine the impact of increasing the difficulty of sensorimotor actions on precision behavior. During initial pressing, reaction time, the rate at which individuals increased their force, the duration of pressing, and force accuracy were measured. During sustained gripping, the complexity of the force time series, force variability, and mean force were examined. During relaxation, the rate at which individuals decreased their force was measured. We also examined the relationships between visuomotor behavior and cytosine-guanine-guanine (CGG) repeat length and clinically rated FXTAS symptoms.

RESULTS

Relative to controls, premutation carriers showed reduced rates of initial force generation during rapid motor actions and longer durations of their initial pressing with their dominant hand. During sustained force, premutation carriers demonstrated reduced force complexity, though this effect was specific to younger premutation carries during dominant hand pressing and was more severe for younger relative to older premutation carriers at low and medium force levels. Increased reaction time and lower sustained force complexity each were associated with greater CGG repeat length for premutation carriers. Increased reaction time and increased sustained force variability were associated with more severe clinically rated FXTAS symptoms.

CONCLUSION

Overall our findings suggest multiple sensorimotor processes are disrupted in aging premutation carriers, including initial force control guided by feedforward mechanisms and sustained sensorimotor behaviors guided by sensory feedback control processes. Results indicating that sensorimotor issues in aging premutation carriers relate to both greater CGG repeat length and clinically rated FXTAS symptoms suggest that quantitative tests of precision sensorimotor ability may serve as key targets for monitoring FXTAS risk and progression.

Sensory ataxia rating scale: Development and validation of a functional scale for patients with sensory neuronopathies

Sensory neuronopathies (SN) result from dorsal root ganglia damage and manifest with a combination of sensory deficits and proprioceptive ataxia. Characterization of the natural history and development of therapeutic trials are hampered by the lack of clinical scales that capture the whole spectrum of SN-related manifestations. We propose and validate a rating instrument for SN. Three experienced neuromuscular specialists developed items to rate SN. The resultant instrument was later validated by the assessment of the intra-class correlation coefficient, for inter-rater validity in 48 SN patients, and later in a smaller subset of 16 patients to assess its intra-rater validity. Standardized Crombach's alpha and Oblimin rotation analysis were performed to verify internal consistency and items' relationship, respectively. Evaluation of Sensory Ataxia Rating Scale (SEARS)'s external validity was performed by comparison to: scale for the assessment and rating of ataxia (SARA), Beck balance scale (BBS), and INCAT sensory sum score (ISS). A 10-item scale with an intra-class correlation coefficient >0.95 for intra- and inter-rating measurements with a good internal consistency (standardized Cronbach's alpha of 0.83) were observed. There was a normal distribution of the scores without a floor or ceiling effect. A moderate to good correlation between SEARS and SARA, BBS, and ISS was observed. SEARS is a reliable, easy-to-perform and consistent instrument to rate SN. Larger cohorts and multicenter studies are needed to validate its usefulness towards possible treatment trials.

Different patterns of movement-related cortical oscillations in patients with myoclonus and in patients with spinocerebellar ataxia

OBJECTIVE

To assess whether different patterns of EEG rhythms during a Go/No-go motor task characterize patients with cortical myoclonus (EPM1) or with spinocerebellar ataxia (SCA).

METHODS

We analyzed event-related desynchronization (ERD) and synchronization (ERS) in the alpha and beta-bands during visually cued Go/No-go task in 22 patients (11 with EPM1, 11 with SCA) and 11 controls.

RESULTS

In the Go condition, the only significant difference was a reduced contralateral beta-ERS in the EPM1 patients compared with controls; in the No-go condition, the EPM1 patients showed prolonged alpha-ERD in comparison with both controls and SCA patients, and reduced or delayed alpha- and beta-ERS in comparison with controls. In both conditions, the SCA patients, unlike EPM1 patients and controls, showed minimal or absent lateralization of alpha- and beta-ERD.

CONCLUSIONS

EPM1 patients showed abnormal ERD/ERS dynamics, whereas SCA patients mainly showed defective ERD lateralization.

SIGNIFICANCE

A different behavior of ERS/ERD distinguished the two patient groups: the pattern observed in EPM1 suggests a prominent defect of inhibition occurring in motor cortex contralateral to activated segment, whereas the pattern observed in SCA suggested a defective lateralization attributable to the damage of cerebello-cortical network, which is instead marginal in patients with cortical myoclonus.

Cerebellar involvement in warts Hypogammaglobulinemia immunodeficiency myelokathexis patients: neuroimaging and clinical findings

Background

Warts Hypogammaglobulinemia Immunodeficiency Myelokathexis (WHIM) syndrome is a primary immunodeficiency characterized by recurrent bacterial infections, severe chronic neutropenia, with lymphopenia, monocytopenia and myelokathexis which is caused by heterozygous gain of functions mutations of the CXC chemokine receptor 4 (CXCR4). WHIM patients display an increased incidence of non-hematopoietic conditions, such as congenital heart disease suggesting that abnormal CXCR4 may put these patients at increased risk of congenital anomalies.

Studies conducted on CXCR4 and SDF-1-deficient mice have demonstrated the role of CXCR4 signaling in neuronal cell migration and brain development. In particular, CXCR4 conditional knockout mice display abnormal cerebellar morphology and poor coordination and balance on motor testing.

Results

In order to evaluate a possible neurological involvement in WHIM syndrome subjects, we performed neurological examination, including International Cooperative Ataxia Rating Scale, cognitive and psychopathological assessment and brain Magnetic Resonance Imaging (MRI) in 6 WHIM patients (age range 8–51 years) with typical gain of functions mutations of CXCR4 (R334X or G336X). In three cases (P3, P5, P6) neurological evaluation revealed fine and global motor coordination disorders, balance disturbances, mild limb ataxia and excessive talkativeness. Brain MRI showed an abnormal orientation of the cerebellar folia involving bilaterally the gracilis and biventer lobules together with the tonsils in four subjects (P3, P4, P5, P6). The neuropsychiatric evaluation showed increased risk of internalizing and/or externalizing problems in four patients (P2, P3, P4, P6).

Conclusions

Taken together, these observations suggest CXCR4 gain of function mutations can be associated with cerebellar malformation, mild neuromotor and psychopathological dysfunction in WHIM patients.

Static and dynamic postural control deficits in aging fragile X mental retardation 1 (FMR1) gene premutation carriers

BACKGROUND

Individuals with premutation alleles of the fragile X mental retardation 1 (FMR1) gene are at risk of developing fragile X-associated tremor/ataxia syndrome (FXTAS) during aging. Characterization of motor issues associated with aging in FMR1 premutation carriers is needed to determine neurodegenerative processes and establish new biobehavioral indicators to help identify individuals at greatest risk of developing FXTAS.

METHODS

We examined postural stability in 18 premutation carriers ages 46-77 years and 14 age-matched healthy controls. Participants completed a test of static stance and two tests of dynamic postural sway on a force platform to quantify postural variability and complexity. CGG repeat length was measured for each premutation carrier, and MRI and neurological evaluations were conducted to identify carriers who currently met criteria for FXTAS. Of the 18 premutation carriers, seven met criteria for definite/probable FXTAS (FXTAS+), seven showed no MRI or neurological signs of FXTAS (FXTAS-), and four were inconclusive due to insufficient data.

RESULTS

Compared to controls, premutation carriers showed increased center of pressure (COP) variability in the mediolateral (COP_ML) direction during static stance and reduced COP variability in the anterior-posterior (COP_AP) direction during dynamic AP sway. They also showed reductions in COP_ML complexity during each postural condition. FXTAS+ individuals showed reduced COP_AP variability compared to FXTAS- carriers and healthy controls during dynamic AP sway. Across all carriers, increased sway variability during static stance and decreased sway variability in target directions during dynamic sways were associated with greater CGG repeat length and more severe neurologically rated posture and gait abnormalities.

CONCLUSION

Our findings indicate that aging FMR1 premutation carriers show static and dynamic postural control deficits relative to healthy controls implicating degenerative processes of spinocerebellar and cerebellar-brainstem circuits that may be independent of or precede the onset of FXTAS. Our finding that FXTAS+ and FXTAS- premutation carriers differed on their level of intentional AP sway suggests that neural mechanisms of dynamic postural control may be differentially impacted in patients with FXTAS, and its measurement may be useful for rapidly and precisely identifying disease presence and onset.

Cross-cultural adaptation and validation of the International Cooperative Ataxia Rating Scale (ICARS) to Brazilian Portuguese

OBJECTIVE

The clinical assessment of patients with ataxias requires reliable scales. We aimed to translate, adapt and validate the International Cooperative Ataxia Rating Scale (ICARS) into Brazilian Portuguese.

METHODS

The steps of this study were forward translation, translation synthesis, backward translation, expert committee meeting, preliminary pilot testing and final assessment. Thirty patients were enrolled in the preliminary pilot testing and 61 patients were evaluated for construct validity, internal consistency, intra- and inter-rater reliability and external consistency.

RESULTS

This study showed good validity of the construct and high internal consistency for the full scale, except for the oculomotor domain (Cronbach's alpha = 0.316, intraclass correlation coefficients intra- = 82.4% and inter- = 79.2%). A high correlation with the Scale for the Assessment and Rating of Ataxia was observed. We found good intra-rater agreement and relative inter-rater disagreement, except in the posture and gait domain.

CONCLUSION

The present ICARS version is adapted for the Brazilian culture and can be used to assess our ataxic patients.

Relationship between subjective visual vertical and balance in individuals with multiple sclerosis

BACKGROUND

Subjective visual vertical (SVV) deviations have been correlated to abnormal cerebellar function in individuals diagnosed with multiple sclerosis (MS). It has been shown that individuals with MS have increased incidence of SVV abnormalities, yet this is not routinely tested in this population during physical therapy evaluation.

OBJECTIVE

This study aims to determine if there is a relationship between SVV and balance performance in people with MS who have cerebellar involvement. We hypothesize that individuals with greater SVV deviations will have worse balance performance.

METHODS

Fifteen females and five males (mean age 54.5 years [±7.03 SD]) with the diagnosis of MS and cerebellar involvement participated. Computerized SVV testing included rod and rod-and-frame conditions. None of the balance outcomes were correlated with the rod-only condition. Because there was a difference in magnitude of results within the rod-and-frame condition, based on whether the frame was rotated clockwise (CW) or counterclockwise (CCW), they were analysed independently.

RESULTS

For all six of the balance outcomes, there was a statistically significant moderate correlation with SVV deviations when the frame was tilted CCW: Barthel Index (r = -0.47, p = 0.018), Berg Balance Score (r = -0.59, p = 0.003), gait velocity (r = -0.52, p = 0.010), International Cooperative Ataxia Rating Scale (r = 0.56, p = 0.006), Scale for the Assessment and Rating of Ataxia (r = 0.62, p = 0.002), and Timed Up and Go (r = 0.58, p = 0.003). Interestingly, the Barthel Index was the only outcome that had statistical significance with a moderate correlation (r = -0.66, p = 0.001) when the frame was rotated CW. In this cohort, greater deviations during the rod-and-frame condition of SVV testing correlated with worse functional outcomes, especially when the frame was tilted CCW.

CONCLUSION

Individuals with MS who demonstrate decreased balance performance may rely more heavily on visual backgrounds. Implementation of SVV assessment for individuals with MS may provide clinicians with valuable information to identify clinical interventions.

Optokinetic nystagmus in patients with SCA: A bedside test for oculomotor dysfunction grading

OBJECTIVE

To characterize the clinical features in patients with spinocerebellar ataxia (SCA) type 1, SCA2, and SCA3 and to evaluate the oculomotor dysfunction by using optokinetic nystagmus (OKN) testing, which may be a sensitive marker.

METHODS

In this prospective observational study, all patients underwent detailed neurologic examination with special emphasis on eye movements. OKN was evaluated with a tape. Disease severity was measured with the International Co-Operative Ataxia Rating Scale (ICARS).

RESULTS

A total of 73 genetically confirmed patients were included, of whom 28, 30, and 15 patients were positive for SCA1, SCA2, and SCA3, respectively. Dystonia was more common in patients with SCA3 (46%), and absent ankle jerk was more common in those with SCA2 (21.4%). Brisk deep tendon reflexes were common in patients with SCA1 (46.6%), followed by patients with SCA3 (26.6%) and SCA2 (7.1%). Vertical OKN was impaired in all patients and absent in 86.6% of patients with SCA1, 96% of those with SCA2, and 80% of those with SCA3. Horizontal OKN was absent in 30% of patients with SCA1, 57% of patients with SCA2, and 33% of those with SCA3. Higher motor disability (posture and gait, kinetic functions [Motor Disability] subscore on the ICARS) was associated with higher oculomotor dysfunction measured by OKN-saccades impairment grading but not with the Ocular Disorder subscore of ICARS (ICARS-OD).

CONCLUSION

OKN-saccades are a better and sensitive bedside clinical tool to quantify oculomotor dysfunction in neurodegenerative ataxias. Its role needs to be tested further in presymptomatic carriers. The current ICARS-OD scale to grade oculomotor dysfunction in degenerative ataxias need to be modified.

Evaluation of the use of the Scale for the Assessment and Rating of Ataxia (SARA) in healthy volunteers and patients with schizophrenia

OBJECTIVE

The Scale for the Assessment and Rating of Ataxia (SARA) is a semi-quantitative assessment used to evaluate ataxia. The goal of these studies was to assess and evaluate the utility of this instrument in a Healthy Volunteer (HV) group and subjects with Schizophrenia (SCZ).

METHODS

Two studies were completed to collect SARA data, in a HV group and in a stable SCZ group. 177 HVs (18-65 years) and 16 SCZs (18-58 years) provided written consent and were assessed using the SARA. Of 177 HV subjects, 88 had 2 SARA assessments (within 2 days of initial visit) while all 16 SCZ had 3 SARA assessments (within 14 days of initial visit).

RESULTS

For the HV group, the mean score ± Std for the SARA on visit-1 was 0.39 ± 0.72, and 0.34 ± 0.64 for visit-2. The Pearson correlation coefficient between visit-1 and visit-2 was 0.7486 and an ICC of 0.743. For the SCZ group, the mean score for the SARA was 0.63 ± 0.65 on visit-1, 0.84 ± 1.19 on visit-2, and 0.84 ± 0.94 on visit-3. The Pearson correlation coefficient between visit-1 and visit-2 was 0.6545, between visit-1 and visit-3 was 0.6635 and between visit-2 and visit-3 was 0.7613 and an ICC of 0.650. There was no significant difference in baseline SARA scores between the HV and SCZ group p = .063. A statistically significant positive association between age and total SARA scores was observed in HV (r = 0.345) and SCZ (r = 0.676).

CONCLUSIONS

A strong association was observed in both the HV and SCZ groups in the reassessment of signs of ataxia using the SARA scale. Both groups demonstrated minimal signs of ataxia, with no statistically significant difference between the two groups in their visit-1 scores.

Paroxysmal motor disorders: expanding phenotypes lead to coalescing genotypes

Paroxysmal movement disorders encompass varied motor phenomena. Less recognized features and wide phenotypic and genotypic heterogeneity are impediments to straightforward molecular diagnosis. We describe a family with episodic ataxia type 1, initially mis‐characterized as paroxysmal dystonia to illustrate this diagnostic challenge. We summarize clinical features in affected individuals to highlight underappreciated aspects and provide comprehensive phenotypic description of the rare familial KCNA1 mutation. Delayed diagnosis in this family is emblematic of the broader challenge of diagnosing other paroxysmal motor disorders. We summarize genotypic and phenotypic overlap and provide a suggested diagnostic algorithm for approaching patients with these conditions.

Psychometric properties of outcome measures evaluating decline in gait in cerebellar ataxia: A systematic review

Cerebellar ataxia often results in impairment in ambulation secondary to gait pattern dysfunction and compensatory gait adjustments. Pharmaceutical and therapy-based interventions with potential benefit for gait in ataxia are starting to emerge, however evaluation of such interventions is hampered by the lack of outcome measures that are responsive, valid and reliable for measurement of gait decline in cerebellar ataxia. This systematic review aimed for the first time to evaluate the psychometric properties of gait and walking outcomes applicable to individuals with cerebellar ataxia. Only studies evaluating straight walking were included. A comprehensive search of three databases (MEDLINE, CINAHL and EMBASE) identified 53 studies meeting inclusion criteria. Forty-nine were rated as 'poor' as assessed by the COnsensus-based Standards for the selection of health Measurement INstruments checklist. The primary objective of most studies was to explore changes in gait related to ataxia, rather than to examine psychometric properties of outcomes. This resulted in methodologies not specific for psychometric assessment. Thirty-nine studies examined validity, 11 examined responsiveness and 12 measured reliability. Review of the data identified double and single support and swing percentage of the gait cycle, velocity, step length and the Scale for Assessment and Rating of Ataxia (SARA) gait item as the most valid and responsive measures of gait in cerebellar ataxia. However, further evaluation to establish their reliability and applicability for use in clinical trials is clearly warranted. We recommend that inter-session reliability of gait outcomes should be evaluated to ensure changes are reflective of intervention effectiveness in cerebellar ataxia.

Scales for the clinical evaluation of cerebellar disorders

Clinical scales represent an important tool not only for the initial grading/scoring of disease and assessment of progression, but also for the quantification of therapeutic effects in clinical trials. There are several scales available for the clinical evaluation of cerebellar symptoms. While some scales have been developed and evaluated for specific cerebellar disorders such as Friedreich ataxia, others reliably capture cerebellar symptoms with no respect to the underlying etiology. Each scale has its strengths and weaknesses. Extensive scales are certainly useful for thorough documentation of specific features of certain phenotypes, but this gain of information is not always essential for the purpose of a study. Therefore, compact and manageable scales like the Scale for the Assessment and Rating of Ataxia (SARA) or Brief Ataxia Rating Scale (BARS) are often preferred compared to more complex scales in observational and therapeutic studies.

Evaluation and treatment of Langerhans cell histiocytosis patients with central nervous system abnormalities: Current views and new vistas

Central nervous system (CNS) involvement in Langerhans cell histiocytosis (LCH) can include mass lesions of the hypothalamic pituitary axis, choroid plexus, cerebrum, and cerebellum or magnetic resonance imaging (MRI) signal abnormalities of the cerebellum, pons, and basal ganglia. The term neurodegenerative (ND) CNS-LCH has been given to the MRI signal abnormalities and neurologic dysfunction, although initially patients may have no clinical symptoms. Standardized evaluations to better understand the natural history and response to therapy are needed. We propose guidelines for clinical, radiologic, and physiologic tests as a framework for developing the best methods of evaluation, which can then be tested in prospective treatment protocols.

Validity and reliability of the International Cooperative Ataxia Rating Scale (ICARS) and the Scale for the Assessment and Rating of Ataxia (SARA) in multiple sclerosis patients with ataxia

BACKGROUND

Ataxia is an extremely common problem in multiple sclerosis (MS) patients. Thus, appropriate scales are required for detailed assessment of this issue. The aim of our study was to investigate the reliability and validity of the Turkish version of the International Cooperative Ataxia Rating Scale (ICARS) and Scale for the Assessment and Rating of Ataxia (SARA), which are widely used in ataxia evaluation in the context of other cerebellar diseases.

METHOD

This cross-sectional study included 80 MS patients with Kurtzke cerebellar functional system score (C-FSS) greater than zero and slight pyramidal involvement. The Expanded Disability Status Scale (EDSS), C-FSS, and Berg Balance Scale (BBS) were administered. SARA and ICARS were assessed on first admission by two physical therapists. Seven days later, second assessments were repeated in same way for reliability.

RESULTS

Intra-rater and inter-rater reliability were found to be high for both ICARS and SARA (p< 0.001) The Cronbach's α coefficients were 0.922 and 0.921 for SARA (reviewer 1 and reviewer 2 respectively) and 0.952 and 0.952 for ICARS (reviewer 1 and reviewer 2, respectively). There were no floor or ceiling effects determined for either scale except for item 17 of ICARS (p= 0.055). The EDSS total score had significant correlations with both SARA and ICARS (rho: 0.557 and 0.707, respectively). C-FSS had moderate correlation with SARA and high correlation with ICARS (rho: 0.469 and 0.653, respectively). BBS had no significant correlation with SARA and ICARS. (rho: -0.048 and -0.008 respectively). According to the area under the curve (AUC) value, ICARS is the best scale to discriminate mild and moderate ataxia. (AUC: 0.875). Factor analyses of ICARS showed that the rating results were determined by five different factors that did not coincide with the ICARS sub-scales.

CONCLUSION

Our study demonstrated that ICARS and SARA are both reliable in MS patients with ataxia. Although ICARS has some structural problems, it seems to be more valid given its high correlations with EDSS and C-FSS. SARA also can be preferred as a brief assessment.

Monitoring disease progression in spinocerebellar ataxias: implications for treatment and clinical research

INTRODUCTION

Spinocerebellar ataxias (SCAs) are autosomal dominant diseases characterized by progressive gait and limb incoordination, disequilibrium, dysarthria, and eye movement disturbances. Approximately 40 genetic subtypes of SCAs are known and classified according to the causative disease gene/locus. With the possibility of the specific genetic diagnosis in patients and at-risk family members, several clinical scales and functional tests have been validated and used in ataxic patients with the purposes of measuring the entity of disease progression in natural history studies and the possible slowing of neurological impairment in therapeutic trials. Areas covered: This paper reviews the most widely used clinical scales and quantitative tests that contributed in monitoring disease progression of the most common forms of SCAs. Expert commentary: The currently available and validated clinical scales and quantitative performance scores are adequate to measure disease severity, but may require a considerable number of subjects and a long period of treatment to allow the recognition of beneficial effect of interventional therapies. Advanced MRI techniques are a consistent biomarker and maybe useful to track disease progression from the preclinical to the manifest ataxic phase in association with appropriate clinical or paraclinical investigations.

Rehabilitation for Individuals With Genetic Degenerative Ataxia: A Systematic Review

BACKGROUND

Treatment of genetic degenerative ataxia is currently based on symptom management and maintenance of function. However, utilization of rehabilitation is limited due to a lack of evidence supporting its efficacy.

OBJECTIVE

This systematic review evaluated rehabilitation interventions for individuals with genetic degenerative ataxia. In addition, long-term outcomes from rehabilitation and optimal duration and intensity of rehabilitation were examined.

METHODS

A comprehensive search of 4 databases (MEDLINE, CINAHL, PEDro, and Cochrane) identified randomized, nonrandomized controlled, and cohort studies published from inception through to January 2016. The studies included at least one measure examining function, ataxia, balance, or gait. Methodological quality was assessed with the Australian National Health and Medical Research Council (NHMRC) Hierarchy of Evidence and the randomized controlled trials were rated according to the PEDro scale.

RESULTS

Seventeen studies met eligibility criteria. Five randomized controlled trials were included; however, the majority were classified as level III-3 and IV studies. Of 292 participants included, 148 had autosomal dominant ataxia, and 85 had autosomal recessive ataxia. Rehabilitation interventions included coordination and balance training, multifaceted inpatient rehabilitation, a cycling regime, balance exercises with technology assisted biofeedback, respiratory muscle training, and treadmill training. Two studies examined adjuncts to rehabilitation. Fifteen of the 17 studies demonstrated a statistically significant improvement in at least 1 outcome measuring ataxia, function, gait, or balance. Less than half of the studies included assessment of long-term outcomes and follow-up time frames varied considerably.

CONCLUSION

There is consistent evidence that rehabilitation improves function, mobility, ataxia, and balance in genetic degenerative ataxia.

Reliability and discriminant validity of ataxia rating scales in early onset ataxia

AIM

To determine whether ataxia rating scales are reliable disease biomarkers for early onset ataxia (EOA).

METHOD

In 40 patients clinically identified with EOA (28 males, 12 females; mean age 15y 3mo [range 5-34y]), we determined interobserver and intraobserver agreement (interclass correlation coefficient [ICC]) and discriminant validity of ataxia rating scales (International Cooperative Ataxia Rating Scale [ICARS], Scale for Assessment and Rating of Ataxia [SARA], and Brief Ataxia Rating Scale [BARS]). Three paediatric neurologists independently scored ICARS, SARA and BARS performances recorded on video, and also phenotyped the primary and secondary movement disorder features. When ataxia was the primary movement disorder feature, we assigned patients to the subgroup 'EOA with core ataxia' (n=26). When ataxia concurred with other prevailing movement disorders (such as dystonia, myoclonus, and chorea), we assigned patients to the subgroup 'EOA with comorbid ataxia' (n=12).

RESULTS

ICC values were similar in both EOA subgroups of 'core' and 'comorbid' ataxia (0.92-0.99; ICARS, SARA, and BARS). Independent of the phenotype, the severity of the prevailing movement disorder predicted the ataxia rating scale scores (β=0.83-0.88; p<0.05).

INTERPRETATION

In patients with EOA, the reliability of ataxia rating scales is high. However, the discriminative validity for 'ataxia' is low. For adequate interpretation of ataxia rating scale scores, application in uniform movement disorder phenotypes is essential.

Cerebellar Symptoms Are Associated With Omission Errors and Variability of Response Time in Children With ADHD

OBJECTIVE

We examined the presence of cerebellar symptoms in ADHD and their association with behavioral markers of this disorder.

METHOD

Sixty-two children with ADHD and 62 typically developing (TD) children were examined for cerebellar symptoms using the ataxia rating scale and tested using Conners' Continuous Performance Test.

RESULTS

Children with ADHD had significantly more cerebellar symptoms compared with the TD children. Cerebellar symptom scores decreased with age in the ADHD group; in the TD group remained stable. In both groups, cerebellar symptoms were associated with parent-rated hyperactive/impulsive symptoms, variability of response time standard error (RT-SE) and increase of RT-SE as the test progresses. More variables were associated with cerebellar symptoms in the ADHD group including omission errors, overall RT-SE and its increase for prolonged interstimulus intervals.

CONCLUSION

Our results highlight the importance of research into motor functions in children with ADHD and indicate a role for cerebellar impairment in this disorder.

Dynamic balance in children with attention-deficit hyperactivity disorder and its relationship with cognitive functions and cerebellum

BACKGROUND

Attention-deficit hyperactivity disorder (ADHD) is linked to the presence of motor deficiencies, including balance deficits. The cerebellum serves as an integrative structure for balance control and is also involved in cognition, including timing and anticipatory regulation. Cerebellar development may be delayed in children and adolescents with ADHD, and inconsistent reaction time is commonly seen in ADHD. We hypothesized that dynamic balance deficits would be present in children with ADHD and they would correlate with attention and cerebellar functions.

METHODS

Sixty-two children with ADHD and no other neurological conditions and 62 typically developing (TD) children were examined with five trials of the Phyaction Balance Board, an electronic balancing platform. Cerebellar clinical symptoms were evaluated using an international ataxia rating scale. Conners' Continuous Performance Test was used to evaluate patterns of reaction.

RESULTS

Children with ADHD had poorer performance on balancing tasks, compared to TD children (P<0.001). They exhibited significantly greater sway amplitudes than TD children (P<0.001) in all of the five balancing trials. The effect size of the difference between the groups increased continuously from the first to the last trial. Balance score in both groups was related to the variation in the reaction time, including reaction time standard error (r =0.25; P=0.0409, respectively, r =0.31; P=0.0131) and Variability of Standard Error (r =0.28; P=0.0252, respectively, r =0.41; P<0.001). The burden of cerebellar symptoms was strongly related to balance performance in both groups (r =0.50, P<0.001; r =0.49, P=0.001).

CONCLUSION

This study showed that ADHD may be associated with poor dynamic balance control. Furthermore, we showed that maintaining balance correlates with neuropsychological measures of consistency of reaction time. Balance deficits and impaired cognitive functioning could reflect a common cerebellar dysfunction in ADHD children.