Clinical characteristics, cerebellar MR spectroscopy and response to 3,4-diaminopyridine in spinocerebellar ataxia 27B: the Sheffield Ataxia Centre experience
Bibliographic record
Abstract
BACKGROUND: The clinical and genetic heterogeneity of hereditary ataxias presents a significant diagnostic challenge, particularly in sporadic adult-onset cases. Spinocerebellar ataxia type 27B (SCA27B) is caused by an intronic GAA·TTC repeat expansion in the fibroblast growth factor 14 (FGF14) gene and is inherited in an autosomal dominant manner, although with reduced penetrance. This novel ataxia is emerging as a frequent yet underdiagnosed cause of late-onset often sporadic cerebellar ataxia. METHOD: In this study, we describe our experience in clinical presentation, neuroimaging characteristics (including MR spectroscopy of the cerebellum), tremor analysis, and therapeutic response to 3,4-diaminopyridine in a cohort of 50 patients with SCA27B. RESULTS: The mean age at onset was 61.8 years. Episodic symptoms were reported in 28% of cases, while downbeat nystagmus and oscillopsia were observed in 50% and 28% individuals, respectively. Tremor was also present in 22% of patients. Tremor analysis demonstrated bilateral, intermediate-frequency (~ 6 Hz) tremor with both action and resting components, occasionally involving, apart from arms, the lower limbs and head. MRI findings revealed involvement of the superior cerebellar peduncle, and MR spectroscopy of the cerebellum (MRS) demonstrated a progressive decline in NAA/Cr area ratios in the cerebellar hemisphere over time. Notably, treatment with 3,4-diaminopyridine was associated with subjective symptom improvement in most patients and objective stabilization and/or improvement on MRS. CONCLUSION: Our findings expand the clinical, neuroimaging and tremor phenotype of SCA27B and support the use of 3,4-diaminopyridine as a potentially effective therapy.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.007 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".