Annals of Clinical and Experimental Neurology

Introduction. Among various chronic polyneuropathies, there are conditions that pose challenges for differential diagnosis: multifocal motor neuropathy (MMN) and Lewis–Sumner syndrome (LSS). The potential of magnetic resonance imaging (MRI) to objectively assess pathological changes in the nerve structures of brachial plexuses remains highly relevant for the diagnosis and differential diagnosis of MMN and LSS.

The aim of this study is to determine the diagnostic value of quantitative methods for assessing MRI signal intensity and thickness measurements of brachial plexus neural elements in differentiating LSS and MMN.

Materials and methods. The study included 59 patients: 26 diagnosed with MMN, 33 with LSS, along with 15 healthy volunteers.

Results. When comparing the combined patient group (regardless of diagnosis) with healthy controls, both nerve thickness and signal intensity coefficient were significantly higher in patients. Additionally, disease-specific threshold values for signal intensity coefficient were established for each condition.

Conclusion. The analysis of signal intensity coefficients LSS and MMN demonstrates that quantitative assessment of MRI signal intensity from the anterior rami of spinal nerves forming brachial plexuses provides additional diagnostic information about pathological changes and facilitates accurate diagnosis. This approach enables earlier initiation of pathogenetic therapy, reduces disability rates, and shortens the duration of patient incapacitation.

Introduction. Hereditary transthyretin amyloid polyneuropathy (hATTR-PN) is a disabling, life-threatening systemic autosomal dominant disease associated with a pathogenic variant of the TTR gene and transthyretin protein misfolding.

The aim of the study was to determine the detection rate of hATTR-PN in a cohort of patients with bilateral carpal tunnel syndrome (CTS) in routine clinical practice in Russia and to assess their demographic and clinical characteristics, including genetic testing results.

Materials and methods. As part of the retrospective part of a multicenter observational study, data from adult patients with a confirmed diagnosis of bilateral CTS were analyzed to identify signs suggestive of probable hATTR-PN. If ≥ 1 sign of the disease (red flags) was present based on medical history, a comprehensive assessment of participants’ clinical characteristics, including neurological examination findings, was conducted during the prospective part. Molecular genetic testing via Sanger sequencing of the TTR gene was performed to confirm or exclude the hATTR-PN. The primary endpoint was the proportion of patients with genetically confirmed hATTR-PN diagnosis.

Results. Among 1,378 patients with carpal tunnel syndrome (CTS) included in the retrospective phase, 1,321 (95.9%) exhibited ≥ 1 feature of hATTR-PN. The most common manifestations were paresthesia and burning sensation in distal extremities without specific localization (89.6%), limb muscle hypotrophy/hypotonia and areflexia (16.1%), and left ventricular hypertrophy (15.4%). In the prospective cohort (n = 723; age 58.5 ± 12.0 years; 82.6% women), hATTR-PN diagnosis was confirmed in 1 patient (0.14%) — a 65-year-old woman with TTR p.Val50Met variant. The interval from CTS symptom onset to hATTR-PN diagnosis exceeded 20 months, with 4 red flags present: heart failure with preserved ejection fraction, ophthalmological abnormalities, paresthesias, and autonomic nervous system dysfunction (constipation). The proportion of hATTR-PN patients in the overall bilateral CTS cohort was 0.073%. Five participants carried other TTR variants with varying clinical significance: p.Ala101Val, p.His110Asn (n = 2), p.Arg5His, and c.[-61G>A].

Conclusion. The detection rate of hATTR-PN in Russian patients with bilateral CTS is 0.073%, reaching 0.076% when ≥ 1 disease feature is present. Considering the p.Arg5His variant classified as of uncertain significance but with published evidence of pathogenicity increases the frequency to 0.14% in bilateral CTS patients. Improvement of screening algorithms for selecting candidates for molecular genetic testing is required to verify diagnosis.

Introduction. Anti-B-cell therapy that prevents clonal expansion of B cells expressing CD20 is a significant achievement in the pharmacotherapy of multiple sclerosis (MS). Randomized studies have shown high efficacy of monoclonal antibodies (mAb), confirmed by a reduction in the annualized relapse rate (ARR), MRI activity, and the risk of disability progression. Divozilimab (DIV) is a humanized afucosylated anti-CD20 mAb with a modified Fc fragment that provides high effector activity.

The aim is to evaluate the efficacy and safety of DIV in patients with various MS phenotypes in real-world clinical practice.

Materials and methods. The prospective study included 43 patients: 24 with rapidly progressive MS, 9 with highly active MS, and 10 with secondary progressive MS with relapses. All received DIV therapy for 6–12 months. We assessed ARR, MRI activity (lesions with contrast enhancement (T1-Gd⁺), new/enlarged T2 lesions), changes in the Expanded Disability Status Scale (EDSS), CD19⁺ B-cell levels, and the safety profile. Data were analyzed before therapy, at 6 months, and at 12 months of treatment.

Results. Over 12 months of therapy, ARR decreased from 1.3 to 0.03; the proportion of patients without T1-Gd⁺ lesions increased from 27.9% to 100%, and new T2 lesions were detected in 6.1%. The median EDSS decreased from 3.0 [2.0; 3.5] to 2.5 [2.0; 3.0]. Profound depletion of CD19⁺ B cells was noted (0% [0.0; 0.2]); NEDA-3 (No Evidence of Disease Activity-3) status was achieved in 84.9%. Adverse events were limited to mild/moderate infusion reactions (30.2% at the first infusion), and no serious adverse events were recorded.

Conclusion. DIV provides rapid and sustained suppression of clinical and MRI activity in MS with pronounced B-cell depletion and a favorable safety profile, justifying its early use in patients with high disease activity.

Parkinson’s disease (PD) is a multisystem neurodegenerative disorder characterized by progressive loss of dopaminergic neurons in the substantia nigra of the midbrain as its key morphological feature. Among neurodegenerative diseases, PD ranks second in prevalence, surpassed only by Alzheimer disease. Epidemiological projections suggest the global population of diagnosed PD patients may reach 8.7 million by 2030, highlighting its significance as a major contemporary medical and social challenge. The progression of the disease leads to persistent maladjustment in all aspects of the patient’s life, resulting in a loss of human resources. Approximately 85–90% of PD cases are sporadic and multifactorial. Recent research has identified genetic mutations predisposing to PD. However, the contribution of environmental factors to PD pathogenesis remains unclear.

This review examines current evidence on both pathogenic and protective effects of environmental factors in the development and progression of sporadic PD.

We conducted a comprehensive search of Russian- and English-language full-text publications over 25 years using eLIBRARY.RU, PubMed, Google Scholar, and Web of Science databases with relevant keywords. The review analyzes pathogenic and protective environmental factors in PD, along with factors of uncertain significance.

Cervical or auricular vagus nerve stimulation (VNS) is an effective and safe non-pharmacological treatment for epilepsy, depression, obesity, post-stroke motor impairments, and certain types of primary headaches (HA), including migraine. This review briefly summarizes data on various VNS device models, the pathophysiology of HA, and approved neuromodulatory therapies for headache management. Experimental findings have been analyzed regarding the role of sensory nuclei of the trigeminal and vagus nerves, as well as supraspinal structures of the central nervous system, particularly the dorsal raphe nucleus and locus coeruleus, in mediating the inhibitory effects of VNS on nociceptive transmission within the trigeminothalamocortical pathway, whose hyperactivity is a key mechanism in HA pathogenesis. The review details studies using rodent migraine models, which demonstrated VNS-mediated suppression of spinal trigeminal nucleus neuronal activity and cortical spreading depression, effects achieved through neurotransmitters such as serotonin, norepinephrine, and gamma-aminobutyric acid (GABA). The mechanisms of VNS therapeutic action in HA should remain a focus of experimental and clinical research, as current evidence in this field requires further updating and validation.

Radiation-induced injury of the internal carotid artery (ICA) is a late complication of radiation therapy administered for neck malignancies. It manifests 5–10 years after radiation therapy as progressive atherosclerotic stenosis of the ICA. Vertebral artery involvement is not characteristic. This report describes a patient who received radiation therapy for laryngeal cancer at age 18, developed transient ischemic attack after 7 years, and experienced an ischemic stroke in the left middle cerebral artery territory 8 years post-treatment. Examination revealed left ICA occlusion and right ICA stenosis that progressed over 2 years without statin therapy. The patient condition remained stable for 13 years, no control examination of the neck arteries was performed. Absence of transient ischemic attack or stroke during this period suggests that vertebral arteries, which provide cerebral blood flow in severe ICA lesions, remain unaffected by the pathological process. This phenomenon is likely attributable to their anatomical course within the bony canal, providing protection from radiation damage.