Corrado Cabona

Background: The definition of motor conduction block (CB) and proximal temporal dispersion (TD) for the diagnosis of CIDP and MMN remains debated, particularly regarding whether CB should be based on amplitude or area reduction, and whether proximal TD is best assessed using negative peak or total CMAP duration. Methods: Nerve conduction waveforms from 106 CIDP, 87 MMN, and 234 controls were analyzed. Motor CB was defined by ≥ 30%, ≥ 40%, or ≥ 50% amplitude or area reduction. Proximal TD was defined as a ≥ 30% increase in negative peak duration, total CMAP duration, or either criterion. Sensitivity, specificity, and inter‐rater reliability were analyzed. Results: Across both CIDP and MMN, a ≥ 30% reduction in CMAP amplitude showed diagnostic performance comparable to area‐based CB definitions and outperformed higher cutoff values. Requiring CB in multiple nerves increased specificity but reduced sensitivity. For proximal TD, negative peak duration was the most robust single parameter. Total CMAP duration identified additional abnormalities and, when combined with negative peak duration, improved diagnostic sensitivity in both disorders while maintaining high specificity. Total CMAP duration demonstrated good inter‐rater agreement at the patient level. CMAP morphology showed substantial overlap between CIDP and MMN and limited discriminatory value. Conclusions: A ≥ 30% reduction in CMAP amplitude can be used as a universal definition of motor CB in both CIDP and MMN, providing diagnostic performance comparable to area‐based criteria with greater simplicity. In addition, proximal TD assessed using total CMAP duration may represent a complementary electrophysiological criterion in both disorders.

Amyotrophic Lateral Sclerosis (ALS) phenotyping is a challenging task due to its heterogeneous nature and low prevalence. In this paper, we introduce a data-driven approach to support the characterization of ALS phenotypes based on clinical data from a battery of examinations. A consensus clustering method is proposed to identify stable clusters across multiple random data sub-samples, with the objective of discovering whether the retrieved patients’ groups and related features align with clinical phenotypes and medical knowledge. Results suggest consistent profiles for bulbar onset ALS patients, driven by onset characteristics, whereas spinal onset ALS patients exhibit greater within-phenotype heterogeneity.

Background and purpose: Neurological involvement in long COVID (coronavirus disease 2019) is well known. In a previous study we identified two subtypes of neurological long COVID, one characterized by memory disturbances, psychological impairment, headache, anosmia and ageusia, and the other characterized by peripheral nervous system involvement, each of which present a different risk factor profile. In this study, we aimed to clarify the persistence of neurological long COVID symptoms with a significantly longer term follow‐up.Methods: We prospectively collected data from patients with prior COVID‐19 infection who showed symptoms of neurological long COVID. We conducted a descriptive analysis to investigate the progression of neurological symptoms over time at 3‐, 6‐, 12‐, and 18‐month follow‐ups. We performed a k‐means clustering analysis on the temporal evolution of the symptoms at 6, 12, and 18 months. Finally, we assessed the difference between the recovery course of vaccinated and non‐vaccinated patients by computing the cumulative recovery rate of symptoms in the two groups.Results: The study confirmed the presence of two subtypes of neurological long COVID. Further, 50% of patients presented a complete resolution of symptoms at 18 months of follow‐up, regardless of which subtype of neurological long COVID they had. Vaccination against SARS‐Cov‐2 appeared to imply a higher overall recovery rate for all neurological symptoms, although the statistical reliability of this finding is hampered by the limited sample size of the unvaccinated patients included in this study.Conclusions: Neurological long COVID can undergo complete resolution after 18 months of follow‐up in 50% of patients and vaccination can accelerate the recovery.

Parsonage-Turner syndrome (PTS) is an idiopathic condition that may be triggered by vaccination against SARS-CoV-2. High-resolution ultrasound can support the diagnosis and monitoring of PTS patients by demonstrating specific nerve abnormalities. The recently implemented superb microvascular imaging technology can help stratify the prognosis of these patients, with the potential to contribute to the clinical management of PTS.

Recent studies suggest that psychological resilience (PR) is associated with more well-preserved cognition in healthy subjects (HS), but an investigation of such phenomenon in patients with motor neuron diseases (MNDs) is still lacking. The aim of our study was therefore to evaluate PR and its relationship with baseline cognitive/behavioral and mood symptoms, as well as longitudinal cognitive functioning, in MNDs. 94 MND patients and 87 demographically matched HS were enrolled. PR was assessed using the Connor-Davidson Resilience Scale (CD-RISC). Patients were further evaluated both at baseline and every 6 months for cognitive/behavioral disturbances using the Edinburgh Cognitive and Behavioral ALS Screen (ECAS), and for mood symptoms using the Hospital Anxiety and Depression Scale (HADS). CD-RISC scores were compared between patients and HS using the Mann-Whitney U test, and regression models were applied to evaluate the role of CD-RISC scores in predicting baseline cognitive/behavioral and mood measures, as well as longitudinal cognitive performances, in MND patients. MND cases showed significantly greater PR compared to HS (p from p from 0.01 to 0.05) and milder mood symptoms (p from p from 0.001 to 0.04) longitudinally. PR is an important protective factor against the onset and evolution of cognitive/mood disturbances in MNDs, suggesting the usefulness of resilience enhancement psychological interventions to prevent or delay cognitive and mood disorders in these neurodegenerative conditions.

Objective: The aim of the present study is to describe the ultrasound (US) and magnetic resonance imaging (MRI) findings in patients with neuropathies affecting the deep (DB) and superficial (SB) branches of the Ulnar nerve (UN) and to investigate the potential role of imaging modalities in the diagnostic workup of these conditions. Materials and methods: We screened our institutional imaging database to identify patients with a diagnosis of UN mononeuropathy, and among them, we reviewed the cases where US disclosed pathological findings affecting the UN terminal divisions. In this latter subgroup, we retrieved available data on MRI and electrodiagnostic tests performed by the patients during the diagnostic workup. All the patients were evaluated with US machines equipped with 17–5-MHz, 18–4-MHz, 24–8-MHz, or 22–8-MHz probes. MRI exams were performed on a 3-T unit equipped with a 64-channel head RF coil. Results: Among 166 patients with UN mononeuropathy, we retrieved 15 patients (9%) for which US detected pathological findings affecting the UN terminal divisions, consisting of 7 cases of DB neuropathy, 4 cases of SB neuropathy, and 4 cases of combined neuropathy involving both nerves. Seven (46.7%) patients were submitted to MRI to integrate US findings. Among patients with SB and DB neuropathies, imaging allowed the identification of 7 traumatic nerve injuries, 2 nerve tumors, and 6 entrapment neuropathies, including 4 cases of nerve compression by a ganglion cyst. Conclusion: High-resolution US and MRI are accurate modalities for the investigation of patients with SB/DB neuropathy, can provide critical information on the cause of nerve damage, and guide therapeutic decisions. Critical relevance statement: High-resolution US and MRI are accurate modalities for the investigation of patients with superficial/deep branch of the ulnar nerve neuropathy. In the proper setting, US may be regarded as a first-line approach in patients with suspected neuropathies affecting these small branches. Key points: • Neuropathies affecting the distal ulnar nerve often require multimodal investigations. • US and MRI can provide detailed morphological information about the terminal branches of the ulnar nerve. • US may be considered as a first-line approach in suspected distal ulnar nerve neuropathies. Graphical

This article presents an updated analysis of the LIGALS register, a prospective study conducted over a ten-year period (2009-2018) in Liguria, Italy, aimed at evaluating the incidence, prevalence, clinical presentation, and management of amyotrophic lateral sclerosis (ALS). We calculated the mean annual crude incidence rate of ALS, assessed the point prevalence of ALS on January 1, 2018, and analyzed demographic factors, clinical characteristics, and clinical management strategies. Data analysis included Cox regression analysis to identify predictors of survival. The mean annual crude incidence rate of ALS was 3.16/100,000 per year (CI 95%) while the point prevalence of ALS on January 1, 2018, was 9.31/100,000 population (CI 95%). Among the patients, 6.5% were familial ALS, while 93.5% were sporadic cases. Clinical management strategies, including percutaneous endoscopic gastrostomy (PEG) and noninvasive ventilation (NIV), were employed. The study observed a stable frequency of NIV initiation and PEG placement over time, with a growing trend toward earlier PEG positioning. The mean survival from symptom onset was 39 months, whereas from diagnosis, it was 26 months. Cox regression analysis identified several predictors of survival, including gender, age at onset and diagnosis, site of onset, diagnostic category, phenotype, and diagnostic delay. This comprehensive analysis provides valuable insights into the long-term trends in ALS epidemiology and clinical management in Liguria, Italy. It underscores the importance of continued research efforts in understanding and addressing the challenges posed by ALS, particularly in terms of early diagnosis and optimizing clinical interventions to improve patient outcomes.

Pure/predominant upper motor neuron (pUMN) and lower motor neuron (pLMN) diseases have significantly better prognosis compared to amyotrophic lateral sclerosis (ALS), but their early differentiation is often challenging. We therefore tested whether a multimodal characterization approach embedding clinical, cognitive/behavioral, genetic, and neurophysiological data may improve the differentiation of pUMN and pLMN from ALS already by the time of diagnosis. Dunn’s and chi-squared tests were used to compare data from 41 ALS, 34 pLMN, and 19 pUMN cases with diagnoses confirmed throughout a 2-year observation period. Area under the curve (AUC) analyses were implemented to identify the finest tools for phenotypes discrimination. Relative to ALS, pLMN showed greater lower limbs weakness, lower UMN burden, and progression rate (p < 0.001–0.04). PUMN showed a greater frequency of lower limbs onset, higher UMN burden, lower ALSFRS-r and MRC progression rates (p < 0.001–0.03), and greater ulnar compound muscle action potential (CMAP) amplitude and tibial central motor conduction time (CMCT) (p = 0.05–0.03). The UMN progression rate was the finest measure to identify pLMN cases (AUC = 90%), while the MRC progression rate was the finest tool to identify pUMN (AUC = 82%). Detailed clinical and neurophysiological examinations may significantly improve MNDs differentiation, facilitating prognosis estimation and ameliorating stratification strategies for clinical trials enrollment.