•Sensitivity of electrophysiology and ultrasound in ulnar neuropathy was highly dependent on clinical severity.•Ultrasound increased the diagnostic yield in very mild and mild ...neuropathies.•Ultrasound localized all the ulnar neuropathies with abnormal non-localizing electrophysiology.
To assess the diagnostic performance of electrophysiology and nerve ultrasound in ulnar neuropathies of varying clinical severity in 135 consecutive patients.
Clinical severity of ulnar neuropathy was graded on a 4 point scale from very mild (symptoms only) to severe (marked atrophy of intrinsic hand muscles). Sensitivity and localization ability of electrophysiology and nerve ultrasound were assessed for each point of the scale.
Ultrasound had higher sensitivity than electrophysiology in clinically very mild (20% and 3% for ultrasound and electrophysiology, respectively) and mild (62% and 47% for ultrasound and electrophysiology, respectively) neuropathies, had greater localizing ability in axonal ulnar neuropathies, and identified nerve hypermobility.
Ultrasound nerve cross-sectional area had strong positive correlation with both clinical and electrophysiological severity scores, but with significant overlap across the severity groups.
The diagnostic work-up of ulnar neuropathies was improved by using both electrophysiology and ultrasound at all levels of clinical severity. Ultrasound increased the diagnostic yield in very mild and mild neuropathies, localized all the ulnar neuropathies with abnormal non-localizing electrophysiology and identified nerve hypermobility.
This is the first detailed analysis of the diagnostic performance of electrophysiology and ultrasound in ulnar neuropathies of varying severity.
Cerebellar ataxia with neuropathy and bilateral vestibular areflexia syndrome (CANVAS) is a recently recognized neurodegenerative disease with onset in mid- to late adulthood. The genetic basis for a ...large proportion of Caucasian patients was recently shown to be the biallelic expansion of a pentanucleotide (AAGGG)n repeat in RFC1. Here, we describe the first instance of CANVAS genetic testing in New Zealand Māori and Cook Island Māori individuals. We show a novel, possibly population-specific CANVAS configuration (AAAGG)10-25(AAGGG)exp, which was the cause of CANVAS in all patients. There were no apparent phenotypic differences compared with European CANVAS patients. Presence of a common disease haplotype among this cohort suggests this novel repeat expansion configuration is a founder effect in this population, which may indicate that CANVAS will be especially prevalent in this group. Haplotype dating estimated the most recent common ancestor at ∼1430 ce. We also show the same core haplotype as previously described, supporting a single origin of the CANVAS mutation.
There is extensive synaptic loss from frontotemporal lobar degeneration, in preclinical models and human in vivo and post mortem studies. Understanding the consequences of synaptic loss for network ...function is important to support translational models and guide future therapeutic strategies. To examine this relationship, we recruited 55 participants with syndromes associated with frontotemporal lobar degeneration and 24 healthy controls. We measured synaptic density with positron emission tomography using the radioligand
CUCB-J, which binds to the presynaptic vesicle glycoprotein SV2A, neurite dispersion with diffusion magnetic resonance imaging, and network function with task-free magnetic resonance imaging functional connectivity. Synaptic density and neurite dispersion in patients was associated with reduced connectivity beyond atrophy. Functional connectivity moderated the relationship between synaptic density and clinical severity. Our findings confirm the importance of synaptic loss in frontotemporal lobar degeneration syndromes, and the resulting effect on behaviour as a function of abnormal connectivity.
Abstract
Digital assessments of motor severity could improve the sensitivity of clinical trials and personalise treatment in Parkinson’s disease (PD) but have yet to be widely adopted. Their ability ...to capture
individual
change across the heterogeneous motor presentations typical of PD remains inadequately tested against current clinical reference standards. We conducted a prospective, dual-site, crossover-randomised study to determine the ability of a 16-item smartphone-based assessment (the index test) to predict subitems from the Movement Disorder Society-Unified Parkinson’s Disease Rating Scale part III (MDS-UPDRS III) as assessed by three blinded clinical raters (the reference-standard). We analysed data from 60 subjects (990 smartphone tests, 2628 blinded video MDS-UPDRS III subitem ratings). Subject-level predictive performance was quantified as the leave-one-subject-out cross-validation (LOSO-CV) accuracy. A pre-specified analysis classified 70.3% (SEM 5.9%) of subjects into a similar category to any of three blinded clinical raters and was better than random (36.7%; SEM 4.3%) classification. Post hoc optimisation of classifier and feature selection improved performance further (78.7%, SEM 5.1%), although individual subtests were variable (range 53.2–97.0%). Smartphone-based measures of motor severity have predictive value at the subject level. Future studies should similarly mitigate against subjective and feature selection biases and assess performance across a range of motor features as part of a broader strategy to avoid overly optimistic performance estimates.
ABSTRACT
Introduction: After noting inconsistent sonographic median nerve cross‐sectional area (CSA) enlargement at the wrist in very elderly patients with carpal tunnel syndrome (CTS), we ...systematically reviewed ultrasound, electrodiagnostic, and clinical data collected over a 12‐month period in patients from 2 age groups: 80–95 years and 40–65 years old. Methods: Clinical and electrodiagnostic CTS severity, sensitivity of ultrasound CSA (against both electrodiagnostic and clinical reference standards), and correlations between ultrasound CSA and clinical and electrodiagnostic severity were compared in both groups. Results: In very elderly patients, despite a higher prevalence of severe CTS, nerve ultrasound was less sensitive than in the younger group (54% vs. 87%, using clinical reference standard), and did not correlate with clinical (r = 0.28, P = 0.10) or electrodiagnostic (r = 0.09, P = 0.60) severity. Discussion: Median nerve ultrasound CSA at the wrist is not a sensitive marker of CTS in very elderly populations. In this work we detail and discuss potential pathophysiological underpinnings of this unexpected finding. Muscle Nerve, 2019
While biallelic POLR3A loss‐of‐function variants are traditionally linked to hypomyelinating leukodystrophy, patients with a specific splice variant c.1909+22G>A manifest as adolescent‐onset spastic ...ataxia without overt leukodystrophy. In this study, we reported eight new cases, POLR3A‐related disorder with c.1909+22 variant. One of these patients showed expanded phenotypic spectrum of generalised dystonia and her sister remained asymptomatic except for hypodontia. Two patients with dystonic arm tremor responded to deep brain stimulation. In our systemic literature review, we found that POLR3A‐related disorder with c.1909+22 variant has attenuated disease severity but frequency of dystonia and upper limb tremor did not differ among genotypes.
Background:
The trigeminal autonomic cephalalgias (TACs) are a group of debilitating, pathophysiologically similar headache syndromes characterized by facial pain and autonomic symptoms in areas ...supplied by the trigeminal nerve. Short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT) is among the rarest of the TAC syndromes and can be particularly recalcitrant to treatment.
Case:
We describe the case of a 50-year old woman with difficult-to-control SUNCT whose pain was completely aborted within hours of commencing intravenous lignocaine therapy and was maintained pain-free after transitioning to oral mexiletine.
Conclusion:
This is the first report of successful transition from intravenous lignocaine to oral mexiletine in SUNCT, and we suggest that this treatment should be tried early in difficult-to-control SUNCT. This therapy is safe, effective and with minimal side effects if administered in an appropriate manner.
PDF
