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Background: Spinocerebellar ataxias (SCAs) are a group of neurodegenerative disorders characterized by progressive ataxia. Although previous studies have focused on cerebral and cerebellar damage, spinal cord involvement in SCAs remains underexplored., Objectives: This study aims to characterize spinal cord abnormalities in SCA2, SCA3, and SCA6 and to identify its phenotypic correlates., Methods: We conducted a multimodal spinal neuroimaging study on 26 SCA3, 16 SCA2, and 14 SCA6 patients, along with matched healthy controls. MRI scanning was performed using a 3 Tesla device, and the Spinal Cord Toolbox (SCT) was employed for morphometric and diffusivity analyses of the cervical spinal cord., Results: Our findings revealed significant spinal cord atrophy and altered white matter microstructural metrics in SCA3 and SCA2 patients compared to controls, with no abnormalities in SCA6. A strong negative correlation was observed between cross-sectional cord area and disease duration in SCA2, suggesting its potential as a biomarker for disease progression., Conclusions: This study highlights the importance of spinal cord imaging in understanding the pathophysiology of SCAs and demonstrates the utility of MRI-based metrics in identifying structural deviations and their clinical correlates. Further longitudinal studies are needed to validate these findings and explore their implications for clinical trials and therapeutic interventions., Competing Interests: Declarations. Conflicts of interest: The authors declare no conflits of interest. Ethical approval: Ethics Committee of Clinics Hospital at University of Campinas approved the study protocol (registered as “CAAE 29869520.8.3001.5404”). The Study was performed compliant to the Declaration of Helsinki., (© 2024. Springer-Verlag GmbH Germany, part of Springer Nature.)

Spastic ataxia is characterized by the combination of cerebellar ataxia with spasticity and other pyramidal features. It is the hallmark of some hereditary ataxias, but it can also occur in some spastic paraplegias and acquired conditions. It often presents with heterogenous clinical features with other neurologic and non-neurological symptoms, resulting in complex phenotypes. In this review, the differential diagnosis of spastic ataxias are discussed and classified in accordance with inheritance. Establishing an organized classification method based on mode inheritance is fundamental for the approach to patients with these syndromes. For each differential, the clinical features, neuroimaging and genetic aspects are reviewed. A diagnostic approach for spastic ataxias is then proposed., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

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.

Background: Spinocerebellar ataxia type 3 (SCA3) is the most common autosomal dominant spinocerebellar ataxia worldwide. Almost all patients with SCA3 exhibit nystagmus and/or saccades impairment., Objective: To investigate the presence of nystagmus as an early neurological manifestation, before ataxia, in some patients with SCA3 in the first six months of the disease., Methods: We evaluated a series of 155 patients with clinically and molecularly proven SCA3 between 2013 and 2020. Data regarding sex, age, age at onset, disease duration, CAG repeat expansion length, first symptom, presence of ataxia, scores on SARA and ICARS scales, and presence and characteristics of nystagmus were collected., Results: We identified seven patients with symptomatic SCA3 who presented with isolated nystagmus. In these seven individuals the age at onset ranged from 24 to 57 years, and disease duration from four to six months., Conclusions: Our study showed that nystagmus may be the first neurological sign in SCA3. This clinical observation reinforces the idea that the neurodegenerative process in SCA3 patients may start in vestibular system connections or in flocculonodular lobe. This study adds relevant information about pre-symptomatic features in SCA3 that may work as basis for a better understanding of brain degeneration and for future therapeutic clinical trials.

Spinocerebellar ataxias (SCAs) are a heterogeneous group of autosomal dominant inherited diseases that share the degeneration of the cerebellum and its connections as their main feature. We performed a detailed description of the natural history of the main SCAs, focusing on epidemiology, progression, haplotype analysis and its correlation with founder effect, and perspective of future treatments. References for this review were identified by an in-depth literature search on PubMed and selected on the basis of relevance to the topic and on the authors' judgment. More than 40 SCAs have been described so far. SCA3 is the most common subtype worldwide, followed by SCA2 and 6. To evaluate the natural history and to estimate the progression of the main SCAs, consortiums were created all over the globe. Clinical rating scales have been developed to provide an accurate estimation of cerebellar clinical deficits, evaluating cerebellar and non-cerebellar signs. Natural history studies revealed that SCA1 patients' functional status worsened significantly faster than in other SCA subtypes, followed by SCA3, SCA2, SCA6, and SCA10. Number of CAG repeats, age of onset, and ataxia severity at baseline are strong contributors to the risk of death in most SCAs. Understanding the natural history of SCAs is extremely important. Although these are rare diseases, the impact they have on the affected individual are enormous. The advances in the field of genetics are helping understand neuronal functions and dysfunctions and allowing the study and development of possible therapies., Competing Interests: Declaration of Competing Interest On behalf of all authors, the corresponding author states that there are no conflicts of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Spinocerebellar ataxia type 1 is an autosomal dominant disorder caused by a CAG repeat expansion in ATXN1, characterized by progressive cerebellar and extracerebellar symptoms. MRI-based studies in SCA1 focused in the cerebellum and connections, but there are few data about supratentorial/spinal damage and its clinical relevance. We have thus designed this multimodal MRI study to uncover the structural signature of SCA1. To accomplish that, a group of 33 patients and 33 age-and gender-matched healthy controls underwent MRI on a 3T scanner. All patients underwent a comprehensive neurological and neuropsychological evaluation. We correlated the structural findings with the clinical features of the disease. In addition, we evaluated the disease progression looking at differences in SCA1 subgroups defined by disease duration. Ataxia and pyramidal signs were the main symptoms. Neuropsychological evaluation disclosed cognitive impairment in 53% with predominant frontotemporal dysfunction. Gray matter analysis unfolded cortical thinning of primary and associative motor areas with more restricted impairment of deep structures. Deep gray matter atrophy was associated with motor handicap and poor cognition skills. White matter integrity loss was diffuse in the brainstem but restricted in supratentorial structures. Cerebellar cortical thinning was found in multiple areas and correlated not only with motor disability but also with verbal fluency. Spinal cord atrophy correlated with motor handicap. Comparison of MRI findings in disease duration-defined subgroups identified a peculiar pattern of progressive degeneration.

Spinocerebellar ataxias (SCA) are a clinically and genetically heterogeneous group of monogenic diseases that share ataxia and autosomal dominant inheritance as the core features. An important proportion of SCAs are caused by CAG trinucleotide repeat expansions in the coding region of different genes. In addition to genetic heterogeneity, clinical features transcend motor symptoms, including cognitive, electrophysiological and imaging aspects. Despite all the progress in the past 25 years, the mechanisms that determine how neuronal death is mediated by these unstable expansions are still unclear. The aim of this article is to review, from an historical point of view, the first CAG-related ataxia to be genetically described: SCA 1.

Introduction: The combination of cerebellar ataxia and spasticity is common. However, autosomal dominant genetic diseases presenting with spastic-ataxia are a smaller group. Pyramidal signs have been frequently observed in several SCA subtypes, particularly in spinocerebellar ataxia type 1., Methods: We prospectively evaluated the pyramidal signs and spasticity in SCA1 patients, and correlated the data with genetic and clinical features., Results: In this study, we observed that spasticity may be an early and presenting feature of SCA1, since 3 patients had pyramidal signs and spasticity as the first neurological sign. SCA1 patients with spasticity were significantly younger., Conclusion: SCA1 may rarely present with pure spastic paraplegia, resembling hereditary spastic paraplegia, before the appearance of cerebellar signs. This observation may confuse the neurologist when a genetic testing is requested for an autosomal dominant spastic paraplegia, directing research to hereditary spastic paraplegia group., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The spinocerebellar ataxias (SCA) are a group of neurodegenerative disorders characterized by heterogeneous clinical presentation. Spinocerebellar ataxia type 7 (SCA7) is caused by an abnormal CAG repeat expansion and includes cerebellar signs associated with visual loss and ophthalmoplegia. Marked anticipation and dynamic mutation is observed in SCA7. Moreover, phenotype variability and very early onset of symptoms may occur. In this article, a large series of Brazilian patients with different SCA subtypes was evaluated, and we compared the age of onset of SCA7 with other SCA. From the 26 patients with SCA7, 4 manifested their symptoms before 10-year-old. Also, occasionally the parents may have the onset of symptoms after their children. In conclusion, our study highlights the genetic anticipation phenomenon that occurs in SCA7 families. Patients with very early onset ataxia in the context of a remarkable family history, must be considered and tested for SCA7.

Objectives: To assess balance and ability to function in patients with spinocerebellar ataxia., Methods: A total of 44 patients with different spinocerebellar ataxia types 1, 2, 3, and 6 were evaluated using the Tinetti balance and gait assessment and the functional independence measure. The scale for the assessment and rating of ataxia and the international cooperative ataxia rating scale were used to evaluate disease severity., Results: Most patients showed significant risk of falls. The balance scores were significantly different in spinocerebellar ataxia types. A significant positive correlation between balance and disease severity was found., Conclusion: Patients with spinocerebellar ataxia have important balance impairment and risk of falls that influence the ability to function such as self-care, transfers, and locomotion. Furthermore, the more severe ataxia is, the more compromised are postural balance, risk of falls, and ability to function.

Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is a neurodegenerative disorder characterized by late-infantile onset spastic ataxia and other neurological features. ARSACS has a high prevalence in northeastern Quebec, Canada. Several ARSACS cases have been reported outside Canada in recent decades. This is the first report of typical clinical and neuroimaging features in a Brazilian family with probable diagnosis of ARSACS.

This article discusses the prevalence of spinocerebellar ataxia type 6 (SCA6) in Japanese immigrants in Brazil. The authors compare the frequency of SCA6 in Japan and Brazil, finding that it is relatively uncommon in Brazil compared to other subtypes of SCA. They also note that all of the SCA6 patients in their study had Japanese ancestry. The authors suggest that genetic diseases should be considered and investigated in individuals with Japanese ancestry, and that this guidance should be applied in other countries as well. [Extracted from the article]