The Pattern and Staging of Brain Atrophy in Spinocerebellar Ataxia Type 2 (SCA2): MRI Volumetrics from ENIGMA-Ataxia.

Objective: Spinocerebellar ataxia type 2 (SCA2) is a rare, inherited neurodegenerative disease characterised by progressive deterioration in both motor coordination and cognitive function. Atrophy of the cerebellum, brainstem, and spinal cord are core features of SCA2, however the evolution and pattern of whole-brain atrophy in SCA2 remain unclear. We undertook a multi-site, structural magnetic resonance imaging (MRI) study to comprehensively characterize the neurodegeneration profile of SCA2. Methods: Voxel-based morphometry analyses of 110 participants with SCA2 and 128 controls were undertaken to assess groupwise differences in whole-brain volume. Correlations with clinical severity and genotype, and cross-sectional profiling of atrophy patterns at different disease stages, were also performed. Results: Atrophy in SCA2 relative to controls was greatest (Cohen's d>2.5) in the cerebellar white matter (WM), middle cerebellar peduncle, pons, and corticospinal tract. Very large effects (d>1.5) were also evident in the superior cerebellar, inferior cerebellar, and cerebral peduncles. In cerebellar grey matter (GM), large effects (d>0.8) mapped to areas related to both motor coordination and cognitive tasks. Strong correlations (|r|>0.4) between volume and disease severity largely mirrored these groupwise outcomes. Stratification by disease severity showed a degeneration pattern beginning in cerebellar and pontine WM in pre-clinical subjects; spreading to the cerebellar GM and cerebro-cerebellar/corticospinal WM tracts; then finally involving the thalamus, striatum, and cortex in severe stages. Interpretation: The magnitude and pattern of brain atrophy evolves over the course of SCA2, with widespread, non-uniform involvement across the brainstem, cerebellar tracts, and cerebellar cortex; and late involvement of the cerebral cortex and striatum.

Treatment of occipital neuralgia using onabotulinum toxin A.

OBJECTIVES: To determine the effectiveness of botulinum toxin in a sample of patients diagnosed with greater occipital nerve neuralgia. MATERIAL AND METHODS: Twenty-nine patients (28 females, 1 male) were treated for greater occipital nerve neuralgia with onabotulinum toxin type A; the Visual Analog Pain Scale was used to determine pain severity at treatment and again 12 weeks after application. RESULTS: Average doses of onabotulinum toxin type A of 18.66±6.44 U per nerve and 35.96±12.89 U per patient were utilized. Average pain severity among the sample was 9.81±0.89 prior to botulinum toxin application and 3.68±2.31 points (p<0.0001) twelve weeks after application. Pain frequency decreased from 29.93±0.37 to 12.17±11.05 days with pain per month (p<0.0001). Six patients reported absence of pain after application (p=0.023). Dose did not correlate with the degree of clinical response observed, and no side effects were reported. CONCLUSION: Our findings suggest onabotulinum toxin type A is a safe and effective treatment alternative for patients suffering from refractory greater occipital nerve neuralgia.

Otoneurological findings in spinocerebellar ataxia.

OBJECTIVE: Describe findings observed in ENG of patients with spinocerebellar ataxias. METHOD: Forty-three patients were studied, and the following procedures were carried out: anamnesis, otorhinolaryngological and vestibular evaluation (ENG). RESULTS: The clinical findings in the entire group of patients were: gait disturbances (83.72%), speech difficulties (48.83%), dizziness (41.86%) and dysphagia (39.53%). Vestibular examination disclosed abnormal caloric exam (83.71%) and saccadic movements (69.76%) with the highest rates of abnormality. The overall presence of alterations in vestibular tests was (90.70%), and the most frequent finding was central vestibular disorder in (74.42%) of patients. CONCLUSION: The study showed that alterations in ENG are related to the severity of SCAs or clinical stage of the disease. We emphasize the importance of studying the vestibular system concomitantly to clinical and genetic follow up.