Modification of heart rate variability induced by focal muscle vibration in patients with severe acquired brain injury.

BACKGROUND/PURPOSE: Heart rate variability (HRV) is a biomarker of autonomic nervous system (ANS) reaction in persons with severe acquired brain injury (sABI) who undergo a rehabilitation treatment, such as focal muscle vibration (FMV).This study aims to evaluate if and how FMV can modulate HRV and to compare potential differences in FMV modulation in HRV between patients with sABI and healthy controls. METHODS: Ten patients with sABI and seven healthy controls have been recruited. Each individual underwent the same stimulation protocol (four consecutive trains of vibration of 5 minutes each with a 1-minute pause). HRV was analyzed through the ratio of frequency domain heart-rate variability (LF/HF). RESULTS: In the control group, after performing FMV, a significant LF/HF difference was observed in the in the second vibration session compared to the POST phase. Patients with SABI treated on the affected side showed a statistically significant LF/HF difference in the PRE compared to the first vibration session. CONCLUSION: These preliminary results suggest that FMV may modify the cardiac ANS activity in patients with sABI.

Nerve Torsion as a Pattern of Parsonage-Turner Syndrome: Literature Review and Two Representative Cases.

(1) Background: Parsonage-Turner Syndrome (PTS) is a rare peripheral nerve disease characterized by different degrees of nerve impairment. The recent development of nerve ultrasound has enabled the use of new data in the diagnosis of the disease. The aim of this study is to conduct a literature review about the ultrasound evaluation of PTS and present two clinical cases that are characteristic of the disease. (2) Methods: A review of the literature from the last 10 years on the topic containing data regarding nerve ultrasound was performed. In addition, two cases of patients on whom nerve ultrasound was performed at the first evaluation and at follow-up after the indicated treatment were described. (3) Results: The results of our review show that although it is defined as plexopathy, PTS is most often a form of multifocal neuropathy. We also report the most frequently used ultrasound classification and possible prognostic correlations and report our experience with the description of two paradigmatic clinical cases. (4) Conclusions: Further studies are needed to understand the true prognostic power of each degree of nerve impairment and the possible implications in clinical practice regarding treatment indications.

The Role of Technological Rehabilitation in Patients with Intensive Care Unit Weakness: A Randomized Controlled Pilot Study.

Intensive-Care-Unit-Acquired Weakness (ICU-AW) is the most common neuromuscular impairment in critically ill patients and can have a significant impact on long-term disability. Early rehabilitation has been suggested to facilitate the natural recovery process. This is a pilot, randomized, single-blind study that aimed to evaluate the effectiveness of intensive combined technological rehabilitation treatment including focal muscle vibration and non-immersive virtual reality for patients with severe acquired brain injury (sABI) and ICU-AW. Twenty-four patients were randomized into the conventional group, which performed only conventional rehabilitation, and the experimental group, which also performed technological treatment. At baseline and after 3 weeks of treatment, assessments of motor function, autonomy, disability and quality of life were conducted. At the end of the intervention, both groups showed significant improvements. However, patients in the experimental group achieved greater improvements in disability (p = 0.001) and quality of life (p = 0.001). The results show that intensive structured rehabilitation is effective in improving the motor function, disability and quality of life of patients with severe acquired brain injury and acquired weakness. The combination of non-immersive virtual reality training and focal muscle vibration can result in a significant improvement in overall disability and quality of life compared with conventional treatment alone.

Carpal tunnel syndrome: updated evidence and new questions.

Carpal tunnel syndrome is the most common entrapment neuropathy, affecting quality of life for many people. Although it is a well recognised condition, new insights into epidemiology, diagnosis, and treatment have emerged in the past 6 years. The availability of disease-modifying treatments for rare systemic disorders associated with carpal tunnel syndrome (eg, amyloidosis) should alert clinicians to these diagnostic possibilities. Besides clinical evaluation and electrophysiology, the role of ultrasonography as a diagnostic tool has been confirmed and new ultrasound techniques have been applied, the clinical use and feasibility of which require further investigation. Surgical and non-surgical interventions are beneficial for the treatment of carpal tunnel syndrome and several treatment options are now available, giving clinicians the possibility to choose the best approach for every patient. New diagnostic and therapeutic techniques require further validation.

Intensive Care Unit-Acquired Weakness and Positioning-Related Peripheral Nerve Injuries in COVID-19: A Case Series of Three Patients and the Latest Literature Review.

A subgroup of COVID-19 patients requires intensive respiratory care. The prolonged immobilization and aggressive treatments predispose these patients to develop intensive care unit-acquired weakness (ICUAW). Furthermore, this condition could increase the chance of positioning-related peripheral nerve injuries. On the basis of the latest literature review, we describe a case series of three patients with COVID-19 who developed ICUAW complicated by positioning-related peripheral nerve injuries Every patient presented sensorimotor axonal polyneuropathy and concomitant myopathy in electrophysiological studies. Furthermore, muscle MRI helped the diagnosis of ICUAW, showing massive damage predominantly in the proximal muscles. Notably, nerve ultrasound detected positioning-related peripheral nerve injuries, even though the concomitant ICUAW substantially masked their clinical features. During the acute phase of severe COVID-19 infection, most medical attention tends to be assigned to critical care management, and neuromuscular complications such as ICUAW and positioning-related peripheral nerve injuries could be underestimated. Hence, when starting post-ICU care for COVID-19 cases, the combination of electrophysiological and imaging studies will aid appropriate evaluation on the patients with COVID-19-related ICUAW.

Efficacy of electrical stimulation of denervated muscle: A multicenter, double-blind, randomized clinical trial.

BACKGROUND: This was a multicenter, double-blind, randomized clinical trial to investigate the efficacy of electrical stimulation of denervated muscle (ESDM) on recovery of patients with peripheral nerve injuries. METHODS: We enrolled 38 patients with traumatic peripheral nerve injuries with axonal damage and clinical impairment of two muscles, who were randomly treated with real or sham electrical stimulation (ES). Clinical and neurophysiological examinations were performed before treatment, at the end of treatment, and 3 mo posttreatment, by the same physician who was blinded to the ES allocation. RESULTS: All patients improved but there was no significant beneficial effect of ESDM compared with sham treatment. CONCLUSIONS: This study failed to demonstrate the efficacy of ESDM for peripheral nerve injuries. However, given the large number of variables related to ES and the heterogeneity in disease etiologies and clinical manifestations, future studies on homogeneous populations using different stimulation protocols may be useful.

Novel sensory paradigms for neuromodulation in disorders of consciousness in traumatic brain injury.

PURPOSE OF REVIEW: Traumatic brain injury (TBI) represents a major cause of mortality and disability worldwide. In cases of severe TBI, disorders of consciousness (DoC) can occur and therapeutic options for these conditions are few and of limited efficacy. Sensory stimulation, an instrument to improve arousal and awareness, is frequently applied in the neurorehabilitation of DoC, but scientific evidence supporting its efficacy is limited. Our aim is to review the recent literature concerning novel sensory paradigms used in sensory stimulation protocols in DoC following TBI. RECENT FINDINGS: Recent studies on sensory stimulation have investigated different types of stimulation protocols, focusing on the issue of how to demonstrate that improvements are related to the treatment applied and not to spontaneous recovery. Moreover, these studies have also shown that paraclinical tests should be useful not only to discover signs of awareness when behavioural assessment fails to do so, but also to measure the effects of sensory stimulation. SUMMARY: Future studies about novel types of sensory stimulation, whose effects should be possibly measured through paraclinical approaches, are recommended in order to increase the probability that the proper individualized stimulation is administered for each patient.

Small fibre neuropathy in mitochondrial diseases explored with sudoscan.

OBJECTIVE: Polyneuropathy in mitochondrial diseases (MDs) is relatively common and widely investigated, but few data are instead reported about small fibres involvement. METHODS: In order to investigate the involvement of small fibres in MDs we performed extensive neurophysiological test (nerve conduction studies; sympathetic skin response; sudoscan) in 27 patients with genetic diagnosis of MD (7 m.3243A > G; 4 m.8344A > G; 9 single mtDNA deletion; 7 multiple mtDNA deletions). RESULTS: NCS showed a polyneuropathy in 11/27 cases (41%). The incidence was very high in POLG1 (100%), m.8344A > G (75%) and m.3243A > G (43%), while only 11% of patients with single deletion had evidence of large fibres involvement. Sympathetic skin response was abnormal only in three patients (one progressive external ophthalmoplegia with single mtDNA deletion; one patient with m.3243A > G mutation; one patient with POLG1 mutation). Sudoscan revealed the presence of an autonomic small fibres dysfunction in 9/27 cases (33%), most of them (7/9) carrying a single mtDNA deletion. Sudoscan data were also confirmed in a sub-group of patients by laser evoked potentials study. Considering only patients with single mtDNA deletion 7/9 (78%) showed abnormal results at sudoscan. CONCLUSIONS: Small fibre neuropathy is another feature to investigate in mitochondrial diseases and seems specifically associated with the presence of single mtDNA deletion. SIGNIFICANCE: The correct identification through specific neurophysiological tests of small fibres involvement in MDs represents another tile in this challenging diagnosis.

Sporadic late-onset nemaline myopathy: clinical, pathology and imaging findings in a single center cohort.

Sporadic late-onset nemaline myopathy (SLONM) is a rare acquired myopathy characterized by rapid-onset proximal weakness in late adulthood, and the presence of nemaline bodies on muscle biopsy. In recent years, several therapeutic interventions, including immunomodulating agents and autologous stem cell transplantation, have shown variable degrees of efficacy in different patients, but no consensus has been reached to allow an effective tailoring of treatments in this severe disease. We performed a retrospective evaluation of clinical, pathological, laboratory, muscle MRI, and follow-up data of SLONM patients diagnosed in the period 2010-2015 in our neuromuscular center. Six patients (three males and three females) were identified. Average time elapsed from the onset of symptoms to referral to the neuromuscular specialist was 23.7 months. Monoclonal gammopathy was detectable in five patients. Nemaline bodies were detected in all the patients, and their abundance correlated with clinical severity. Signs of cardiac involvement were present in all the patients to different extents. Muscle MRI showed a preferential involvement of neck extensors, paraspinal, gluteal, hamstring and soleus muscles. All patients were treated with prednisone and repeated courses of intravenous immunoglobulins, and a favorable outcome was reached in five patients. Our experience confirms that SLONM is clinically characterized by subacute proximal and axial muscle weakness. Time to referral was relatively long and should be reduced with increasing awareness of the disease. Muscle MRI could be of help as a diagnostic tool to identify this potentially treatable myopathy. Cardiac evaluation should be warranted in all SLONM patients to detect subclinical heart involvement.

"Myo-cardiomyopathy" is commonly associated with the A8344G "MERRF" mutation.

The objective of the study was to better characterize the clinical phenotype associated with the A8344G "MERRF" mutation of mitochondrial DNA. Fifteen mutated patients were extensively investigated. The frequency of main clinical features was: exercise intolerance and/or muscle weakness 67 %, respiratory involvement 67 %, lactic acidosis 67 %, cardiac abnormalities 53 %, peripheral neuropathy 47 %, myoclonus 40 %, epilepsy 40 %, ataxia 13 %. A restrictive respiratory insufficiency requiring ventilatory support was observed in about half of our patients. One patient developed a severe and rapidly progressive cardiomyopathy requiring cardioverter-defibrillator implantation. Five patients died of overwhelming, intractable lactic acidosis. Serial muscle MRIs identified a consistent pattern of muscle involvement and progression. Cardiac MRI showed non-ischemic late gadolinium enhancement in the left ventricle inferolateral part as early sign of myocardial involvement. Brain spectroscopy demonstrated increased peak of choline and reduction of N-acetylaspartate. Lactate was never detected in brain areas, while it could be documented in ventricles. We confirm that muscle involvement is the most frequent clinical feature associated with A8443G mutation. In contrast with previous reports, however, about half of our patients did not develop signs of CNS involvement even in later stages of the disease. The difference may be related to the infrequent investigation of A8344G mutation in 'pure' mitochondrial myo-cardiomyopathy, representing a bias and a possible cause of syndrome's underestimation. Our study highlights the importance of lactic acidosis and respiratory muscle insufficiency as critical prognostic factors. Muscle and cardiac MRI and brain spectroscopy may be useful tools in diagnosis and follow-up of MERRF.