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1.
Eur J Neurol ; 31(1): e16030, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37548584

RESUMO

BACKGROUND: Acute hepatitis E virus (HEV) infection has recently emerged as a potential trigger for acute dysimmune neuropathies, but prospective controlled studies are lacking. AIMS: To compare the frequency of concomitant acute HEV infection in patients with neuralgic amyotrophy (NA), Guillain-Barré syndrome (GBS), and Bell's palsy with a matched control population. METHODS: Swiss multicenter, prospective, observational, matched case-control study over 3 years (September 2019-October 2022). Neurological cases with NA, GBS, or Bell's palsy were recruited within 1 month of disease onset. Healthy controls were matched for age, sex, geographical location, and timing of blood collection. Diagnostic criteria for acute hepatitis E were reactive serum anti-HEV IgM and IgG assays (ELISA test) and/or HEV RNA detection in serum by real-time polymerase chain reaction (RT-PCR). RT-PCR was performed on sera to confirm IgM positivity. RESULTS: We included 180 patients (59 GBS, 51 NA, 70 Bell's palsy cases) and corresponding matched controls (blood donors) with median age 51 years for both groups and equal gender distribution. Six IgM+ cases were detected in the NA, two in the GBS, and none in the Bell's palsy group. Two controls were anti-HEV IgM-positive. At disease onset, most cases with acute HEV infection had increased liver enzymes. A moderate association (p = 0.027, Fisher's exact test; Cramér's V = -0.25) was observed only between acute HEV infection and NA. CONCLUSION: This prospective observational study suggests an association between concomitant acute HEV infection and NA, but not with GBS or Bell's palsy.


Assuntos
Paralisia de Bell , Paralisia Facial , Síndrome de Guillain-Barré , Vírus da Hepatite E , Hepatite E , Humanos , Pessoa de Meia-Idade , Vírus da Hepatite E/genética , Hepatite E/complicações , Hepatite E/epidemiologia , Hepatite E/diagnóstico , Estudos de Casos e Controles , Estudos Prospectivos , Paralisia de Bell/complicações , Síndrome de Guillain-Barré/epidemiologia , Anticorpos Anti-Hepatite , Doença Aguda , Imunoglobulina M
2.
Ann Neurol ; 91(1): 66-77, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34761434

RESUMO

OBJECTIVE: Small fiber neuropathy (SFN) is clinically and etiologically heterogeneous. Although autoimmunity has been postulated to be pathophysiologically important in SFN, few autoantibodies have been described. We aimed to identify autoantibodies associated with idiopathic SFN (iSFN) by a novel high-throughput protein microarray platform that captures autoantibodies expressed in the native conformational state. METHODS: Sera from 58 SFN patients and 20 age- and gender-matched healthy controls (HCs) were screened against >1,600 immune-related antigens. Fluorescent unit readout and postassay imaging were performed, followed by composite data normalization and protein fold change (pFC) analysis. Analysis of an independent validation cohort of 33 SFN patients against the same 20 HCs was conducted to identify reproducible proteins in both cohorts. RESULTS: Nine autoantibodies were screened with statistical significance and pFC criteria in both cohorts, with at least 50% change in serum levels. Three proteins showed consistently high fold changes in main and validation cohorts: MX1 (FC = 2.99 and 3.07, respectively, p = 0.003, q = 0.076), DBNL (FC = 2.11 and 2.16, respectively, p = 0.009, q < 0.003), and KRT8 (FC = 1.65 and 1.70, respectively, p = 0.043, q < 0.003). Further subgroup analysis into iSFN and SFN by secondary causes (secondary SFN) in the main cohort showed that MX1 is higher in iSFN compared to secondary SFN (FC = 1.61 vs 0.106, p = 0.009). INTERPRETATION: Novel autoantibodies MX1, DBNL, and KRT8 are found in iSFN. MX1 may allow diagnostic subtyping of iSFN patients. ANN NEUROL 2022;91:66-77.


Assuntos
Autoanticorpos/imunologia , Autoantígenos/imunologia , Neuropatia de Pequenas Fibras/imunologia , Adulto , Idoso , Autoanticorpos/sangue , Estudos de Coortes , Feminino , Humanos , Queratina-8/imunologia , Masculino , Proteínas dos Microfilamentos/imunologia , Pessoa de Meia-Idade , Proteínas de Resistência a Myxovirus/imunologia , Neuropatia de Pequenas Fibras/sangue , Domínios de Homologia de src/imunologia
3.
Muscle Nerve ; 68(4): 375-379, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37074101

RESUMO

Neuromuscular ultrasound has become an integral part of the diagnostic workup of neuromuscular disorders at many centers. Despite its growing utility, uniform standard scanning techniques do not currently exist. Scanning approaches for similar diseases vary in the literature creating heterogeneity in the studies as reported in several meta-analysis. Moreover, neuromuscular ultrasound experts including the group in this study have different views with regards to technical aspects, scanning protocols, and the parameters that should be assessed. Establishing standardized neuromuscular scanning protocols is essential for the development of the subspeciality to ensure uniform clinical and research practices. Therefore, we aimed to recommend consensus-based standardized scanning techniques and protocols for common neuromuscular disorders using the Delphi approach. A panel of 17 experts participated in the study, which consisted of three consecutive electronic surveys. The first survey included voting on six scanning protocols addressing the general scanning technique and five common categories of suspected neuromuscular disorders. The subsequent surveys focused on refining the protocols and voting on new steps, rephrased statements, or areas of non-agreement. A high degree of consensus was achieved on the general neuromuscular ultrasound scanning technique and the scanning protocols for focal mononeuropathies, brachial plexopathies, polyneuropathies, amyotophic lateral sclerosis, and muscle diseases. In this study, a group of neuromuscular ultrasound experts developed six consensus-based neuromuscular ultrasound scanning protocols that may serve as references for clinicians and researchers. The standardized protocols could also aid in achieving high-quality uniform neuromuscular ultrasound practices.


Assuntos
Neuropatias do Plexo Braquial , Doença dos Neurônios Motores , Doenças Neuromusculares , Polineuropatias , Humanos , Doenças Neuromusculares/diagnóstico por imagem , Ultrassonografia/métodos , Metanálise como Assunto
4.
Muscle Nerve ; 64(3): 293-300, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34075618

RESUMO

INTRODUCTION/AIM: There is currently insufficient clinical and epidemiological data concerning small fiber neuropathy (SFN). This research analyzes data from medical records to determine epidemiology, demographics, clinical characteristics and etiology of SFN. METHODS: This is a retrospective, observational study of sequential patients diagnosed with definite SFN (typical clinical features, normal nerve conduction studies, abnormal epidermal nerve fiber density) from the end of November 2016 to the middle of July 2019 at the Cantonal Hospital Lucerne, central Switzerland. RESULTS: A total of 84 patients (64.3% female) with a mean age of 54.7 y were analyzed. Symptoms had been present in patients for an average of 4.8 y when entering the study. A length dependent clinical pattern was seen in 79.8%. All patients had sensory discomfort. Etiology could not be determined in 35.7% of patients, who were diagnosed with idiopathic SFN; 34.5% of patients had an apparently autoimmune SFN, followed by14.3% of patients with metabolic causes. The estimated incidence was at least 4.4 cases/100.000 inhabitants/y. The minimum prevalence was 131.5 cases/100.000 inhabitants. DISCUSSION: This study indicates significant incidence and prevalence rates of SFN in Switzerland. SFN can vary greatly in its symptoms and severity. Extensive work-up resulted in two thirds of the patients being assigned an etiological association. The largest group of patients could not be etiologically defined, underlining the importance of further research on etiologic identification. We expect increased awareness of the developing field of SFN.


Assuntos
Condução Nervosa/fisiologia , Pele/inervação , Neuropatia de Pequenas Fibras/diagnóstico , Adulto , Idoso , Biópsia , Eletrodiagnóstico , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Pele/patologia , Neuropatia de Pequenas Fibras/epidemiologia , Neuropatia de Pequenas Fibras/patologia , Neuropatia de Pequenas Fibras/fisiopatologia , Inquéritos e Questionários , Suíça
5.
Muscle Nerve ; 63(5): 651-656, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33382094

RESUMO

Neuromuscular ultrasound is a rapidly evolving specialty with direct application for patient care. Competency assessment is an essential standard needed to ensure quality for practitioners, particularly for those newly acquiring skills with the technique. Our aim was to survey experts' opinions regarding physician competency assessment of neuromuscular ultrasound and to identify minimal competency of knowledge and skills. The opinions of 18 experts were obtained through the Delphi method using two consecutive electronic surveys. A high degree of consensus was achieved on items regarding framework and the conduct of neuromuscular ultrasound assessment and the knowledge and skills that a candidate needs to attain minimal competency in neuromuscular ultrasound. In this study, a group of neuromuscular ultrasound experts developed a general framework for neuromuscular ultrasound competency assessment and recommended testable areas of knowledge and skills suitable for establishing minimal competency.


Assuntos
Competência Clínica , Músculo Esquelético/diagnóstico por imagem , Doenças Neuromusculares/diagnóstico por imagem , Ultrassonografia/métodos , Consenso , Pesquisas sobre Atenção à Saúde , Humanos , Monitoração Neuromuscular
6.
Support Care Cancer ; 28(8): 3691-3699, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31811482

RESUMO

PURPOSE: Severe peripheral neuropathy is a common dose-limiting toxicity of taxane chemotherapy, with no effective treatment. Frozen gloves have shown to reduce the severity of neuropathy in several studies but comes with the incidence of undesired side effects such as cold intolerance and frostbite in extreme cases. A device with thermoregulatory features which can safely deliver tolerable amounts of cooling while ensuring efficacy is required to overcome the deficiencies of frozen gloves. The role of continuous-flow cooling in prevention of neurotoxicity caused by paclitaxel has been previously described. This study hypothesized that cryocompression (addition of dynamic pressure to cooling) may allow for delivery of lower temperatures with similar tolerance and potentially improve efficacy. METHOD: A proof-of-concept study was conducted in cancer patients receiving taxane chemotherapy. Each subject underwent four-limb cryocompression with each chemotherapy infusion (three hours) for a maximum of 12 cycles. Cryocompression was administered at 16 °C and cyclic pressure (5-15 mmHg). Skin surface temperature and tolerance scores were recorded. Neuropathy was assessed using clinician-graded peripheral sensory neuropathy scores, total neuropathy score (TNS) and nerve conduction studies (NCS) conducted before (NCSpre), after completion (NCSpost) and 3 months post-chemotherapy (NCS3m). Results were retrospectively compared with patients who underwent paclitaxel chemotherapy along with continuous-flow cooling and controls with no hypothermia. RESULTS: In total, 13 patients underwent 142 cycles of cryocompression concomitant with chemotherapy. Limb hypothermia was well tolerated, and only 1 out of 13 patients required an intra-cycle temperature increase, with no early termination of cryocompression in any subject. Mean skin temperature reduction of 3.8 ± 1.7 °C was achieved. Cryocompression demonstrated significantly greater skin temperature reductions compared to continuous-flow cooling and control (p < 0.0001). None of the patients experienced severe neuropathy (clinician-assessed neuropathy scores of grade 2 or higher). NCS analysis showed preservation of motor amplitudes at NCS3m in subjects who underwent cryocompression, compared to the controls who showed significant deterioration (NCS3m cryocompression vs. NCS3m control: ankle stimulation: 8.1 ± 21.4%, p = 0.004; below fibula head stimulation: 12.7 ± 25.6%, p = 0.0008; above fibula head stimulation: 9.4 ± 24.3%, p = 0.002). Cryocompression did not significantly affect taxane-induced changes in sensory nerve amplitudes. CONCLUSION: When compared to continuous-flow cooling, cryocompression permitted delivery of lower temperatures with similar tolerability. The lower skin surface temperatures achieved potentially lead to improved efficacy in neurotoxicity amelioration. Larger studies investigating cryocompression are required to validate these findings.


Assuntos
Crioterapia/métodos , Docetaxel/administração & dosagem , Hipotermia Induzida/métodos , Síndromes Neurotóxicas/prevenção & controle , Paclitaxel/administração & dosagem , Doenças do Sistema Nervoso Periférico/prevenção & controle , Adulto , Idoso , Crioterapia/efeitos adversos , Docetaxel/efeitos adversos , Extremidades/irrigação sanguínea , Feminino , Humanos , Hipotermia Induzida/efeitos adversos , Masculino , Pessoa de Meia-Idade , Neoplasias , Síndromes Neurotóxicas/etiologia , Paclitaxel/efeitos adversos , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Projetos Piloto , Estudos Retrospectivos , Resultado do Tratamento
7.
Muscle Nerve ; 60(4): 361-366, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31335971

RESUMO

Neuromuscular ultrasound has become an essential tool in the diagnostic evaluation of various neuromuscular disorders, and, as such, there is growing interest in neuromuscular ultrasound training. Effective training is critical in mastering this modality. Our aim was to develop consensus-based guidelines for neuromuscular ultrasound training courses. A total of 18 experts participated. Expert opinion was sought through the Delphi method using 4 consecutive electronic surveys. A high degree of consensus was achieved with regard to the general structure of neuromuscular ultrasound training; the categorization of training into basic, intermediate, and advanced levels; the learning objectives; and the curriculum for each level. In this study, a group of neuromuscular ultrasound experts established consensus-based guidelines for neuromuscular ultrasound training. These guidelines can be used in the development of the specialty and the standardization of neuromuscular ultrasound training courses and workshops.


Assuntos
Competência Clínica , Currículo , Guias como Assunto , Neurologistas/educação , Doenças Neuromusculares/diagnóstico por imagem , Ultrassonografia/normas , Técnica Delphi , Humanos , Fisiatras/educação , Radiologistas/educação , Reumatologistas/educação
8.
J Shoulder Elbow Surg ; 28(6): 1033-1039, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30713061

RESUMO

BACKGROUND: This study evaluated the feasibility and reliability of high-resolution ultrasonography (HRUS) of the radial nerve in the early, postoperative period after operative stabilization of humeral shaft fractures. METHODS: This study enrolled patients between September 2015 and April 2018 with a humeral shaft fracture who were assessed with HRUS within 2 weeks after surgery. Based on the ultrasound artifacts, the examiners subjectively defined quality of ultrasound as "bad" or "good." The cross-sectional area of the radial and the posterior interosseous nerve was recorded at predefined locations. The radial nerve was scanned axially in the whole course to identify nerve continuity. RESULTS: Of 44 patients who underwent operations for humeral shaft fracture, HRUS was used to assess 15 patients at an average 4.8 ± 2.6 days (range, 2-11 days) after surgery. The examiners defined ultrasound quality as "good" in 13 of 15 patients (~87%). Primary radial nerve palsy (RNP) was identified in 3 of the 15 patients, and 4 sustained secondary RNP. Nerve continuity was demonstrated by HRUS in every patient. In patients with RNP, nerve continuity was secondarily confirmed by surgical exploration or functional and electrophysiological recovery. CONCLUSION: Early postoperative HRUS of the radial nerve after osteosynthesis of humeral shaft fractures is a feasible and reliable method to identify radial nerve continuity. In case of pathology, this assessment tool can additionally provide valuable information concerning location and etiology of the RNP.


Assuntos
Fraturas do Úmero/cirurgia , Nervo Radial/diagnóstico por imagem , Neuropatia Radial/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fixação Interna de Fraturas/métodos , Humanos , Fraturas do Úmero/reabilitação , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Complicações Pós-Operatórias/etiologia , Reprodutibilidade dos Testes , Ultrassonografia , Adulto Jovem
9.
Muscle Nerve ; 57(2): 320-324, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28667708

RESUMO

INTRODUCTION: We present a painful small-fiber neuropathy variant of Guillain-Barré syndrome characterized by antecedent infectious symptoms, hyporeflexia, and albuminocytologic dissociation. METHODS: Two patients received intravenous immunoglobulin, one corticosteroids. RESULTS: The patients subsequently improved. Immunoglobulin G (IgG) antibodies in their acute phase sera strongly bound to murine small nerve fibers, and the binding disappeared during the convalescent phase. Serum transfer to a murine nociceptive model induced transient alteration in thermal pain responses. DISCUSSION: Our case series suggest that an acute transient immune response can be directed against small nerve fibers, and that patients so affected can exhibit features of Guillain-Barré syndrome. Muscle Nerve 57: 320-324, 2018.


Assuntos
Doenças Autoimunes/patologia , Síndrome de Guillain-Barré/patologia , Dor/patologia , Neuropatia de Pequenas Fibras/patologia , Adolescente , Corticosteroides/uso terapêutico , Adulto , Idoso , Animais , Autoanticorpos/farmacologia , Doenças Autoimunes/tratamento farmacológico , Feminino , Pé/inervação , Pé/patologia , Síndrome de Guillain-Barré/tratamento farmacológico , Humanos , Imunização Passiva , Imunoglobulina G/imunologia , Masculino , Camundongos , Fibras Nervosas/patologia , Dor/tratamento farmacológico , Medição da Dor , Neuropatia de Pequenas Fibras/tratamento farmacológico , Adulto Jovem
10.
Ther Umsch ; 75(7): 458-464, 2018.
Artigo em Alemão | MEDLINE | ID: mdl-30935359

RESUMO

A selection of advances in neuromuscular medicine Abstract. Significant developments in the realm of neuromuscular medicine have occurred in both non-invasive diagnostics as well as treatments. Whole body muscle MRI can detect disease specific patterns and lead to the implementation of direct molecular genetic diagnostics. Bedside neuromuscular ultrasound can assist in diagnosing inflammatory neuropathies even in some cases enabling the omission of nerve biopsy and lumbar puncture. Specific antibodies aid in the classification and management of acquired autoimmune diseases. First effective genetic therapies for monogenetic neuromuscular illnesses are now available for spinal muscular atrophy and familial transthyretin amyloidosis. This overview aims to highlight select new diagnostic and therapeutic achievements in the realm of neuromuscular medicine.


Assuntos
Doenças Neuromusculares , Biópsia , Terapia Genética , Humanos , Imageamento por Ressonância Magnética , Doenças Neuromusculares/diagnóstico , Doenças Neuromusculares/genética , Patologia Molecular
11.
Muscle Nerve ; 56(5): 919-924, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28093784

RESUMO

INTRODUCTION: In this study we propose electrodiagnostic criteria for early reversible conduction failure (ERCF) in axonal Guillain-Barré syndrome (GBS) and apply them to a cohort of GBS patients. METHODS: Serial nerve conduction studies (NCS) were retrospectively analyzed in 82 GBS patients from 3 centers. The criteria for the presence of ERCF in a nerve were: (i) a 50% increase in amplitude of distal compound muscle action potentials or sensory nerve action potentials; or (ii) resolution of proximal motor conduction block with an accompanying decrease in distal latencies or compound muscle action potential duration or increase in conduction velocities. RESULTS: Of 82 patients from 3 centers, 37 (45%) had ERCF, 21 (26%) had a contrasting evolution pattern, and 8 (10%) had both. Sixteen patients did not show an amplitude increase of at least 50%. CONCLUSION: Our proposed criteria identified a group of patients with a characteristic evolution of NCS abnormality that is consistent with ERCF. Muscle Nerve 56: 919-924, 2017.


Assuntos
Eletrodiagnóstico , Potencial Evocado Motor/fisiologia , Síndrome de Guillain-Barré/fisiopatologia , Condução Nervosa/fisiologia , Autoanticorpos/sangue , Feminino , Gangliosídeos/imunologia , Síndrome de Guillain-Barré/sangue , Síndrome de Guillain-Barré/patologia , Humanos , Cooperação Internacional , Masculino , Músculo Esquelético/fisiopatologia , Estudos Retrospectivos
12.
Muscle Nerve ; 53(5): 671-82, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26872938

RESUMO

Etiological and clinical heterogeneity of small fiber neuropathy (SFN) precludes a unifying approach and necessitates reliance on recognizable clinical syndromes. Symptoms of SFN arise from dysfunction in nociception, temperature, and autonomic modalities. This review focuses on SFN involving nociception and temperature, examining epidemiology, etiology, clinical presentation, diagnosis, pathophysiology, and management. Prevalence of SFN is 52.95 per 100,000 population, and diabetes and idiopathic are the most common etiologies. Dysesthesia, allodynia, pain, burning, and coldness sensations frequently present in a length-dependent pattern. Additional autonomic features in gastrointestinal, urinary, or cardiovascular systems are frequent but poorly objectified. SFN is diagnosed by intraepidermal nerve fiber density and quantitative sensory and autonomic tests in combination with normal nerve conduction. Pathophysiological understanding centers on sodium channel dysfunction, and genetic forms are beginning to be understood. Treatment is directed at the underlying etiology supported by symptomatic treatment using antidepressants and anticonvulsants. Little is known about long-term outcomes, and systematic cohort studies are needed.


Assuntos
Doenças do Sistema Nervoso Autônomo/fisiopatologia , Neuropatias Diabéticas/fisiopatologia , Eritromelalgia/fisiopatologia , Hiperalgesia/fisiopatologia , Parestesia/fisiopatologia , Anticonvulsivantes/uso terapêutico , Antidepressivos/uso terapêutico , Doenças do Sistema Nervoso Autônomo/etiologia , Neuropatias Diabéticas/epidemiologia , Neuropatias Diabéticas/terapia , Gerenciamento Clínico , Eritromelalgia/complicações , Eritromelalgia/epidemiologia , Eritromelalgia/terapia , Humanos , Hiperalgesia/etiologia , Condução Nervosa , Nociceptividade/fisiologia , Parestesia/etiologia , Canais de Sódio , Temperatura
13.
Muscle Nerve ; 53(6): 906-12, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26562220

RESUMO

INTRODUCTION: Tarsal tunnel syndrome (TTS) arises from tibial nerve damage under the flexor retinaculum of the fibro-osseus tunnel at the medial malleolus. It is notoriously difficult to diagnose, as many other foot pathologies result in a similar clinical picture. We examined the additional value of nerve ultrasound in patients with tarsal tunnel syndrome confirmed by nerve conduction. METHODS: We performed a retrospective analysis of nerve ultrasound changes in electrophysiologically confirmed TTS spanning our records from 2007 to 2015. RESULTS: Nine feet with TTS were identified, all of which showed abnormal nerve ultrasound findings, which in 6 feet, led to identification of the underlying cause. CONCLUSIONS: This study shows that nerve ultrasound is abnormal in all cases of electrophysiologically verified TTS. The pattern of nerve abnormality is varied. This, and the fact that in the majority of patients causation was identified, suggests nerve ultrasound should form part of standard work-up for TTS. Muscle Nerve 53: 906-912, 2016.


Assuntos
Condução Nervosa/fisiologia , Síndrome do Túnel do Tarso/diagnóstico por imagem , Síndrome do Túnel do Tarso/fisiopatologia , Ultrassonografia/métodos , Potenciais de Ação/fisiologia , Adulto , Idoso , Estudos Transversais , Feminino , Lateralidade Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Nervo Tibial/diagnóstico por imagem , Nervo Tibial/fisiopatologia
14.
Acta Oncol ; 55(4): 430-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26360921

RESUMO

INTRODUCTION: Chemotherapy-induced peripheral neuropathy (CIPN) is a major dose-limiting side effect of several chemotherapeutic agents, often leading to treatment discontinuation. Up to 20% of patients treated with weekly paclitaxel experience severe CIPN and no effective treatment has been established so far. The mechanisms of CIPN damage are unclear, but are directly dose-related. We had earlier demonstrated, in rats, the influence of hypothermia in reducing nerve blood flow. Here, we hypothesize that continuous flow limb hypothermia during chemotherapy reduces the incidence and severity of CIPN, by limiting deliverance of the neurotoxic drug to the peripheral nerves. In this study, prior to assessing the effect of hypothermia in preventing CIPN in cancer subjects undergoing paclitaxel chemotherapy, we assess the safety and tolerable temperatures for limb hypothermia in healthy human subjects. MATERIAL AND METHODS: In 15 healthy human subjects, hypothermia was administered as continuous flow cooling, unilaterally, via a thermoregulator setup covering the digits up to the elbow/knee, along with continuous skin temperature monitoring. Thermoregulator coolant temperatures between 25 °C and 20 °C were tested for tolerability, based on a carefully designed temperature regulation protocol, and maintained for three hours mimicking the duration of chemotherapy. Tolerability was evaluated using various safety and tolerability scores to monitor the subjects. RESULTS: At the end of the cooling session the healthy subjects presented without significant adverse effects, the main being brief mild skin erythema and transient numbness. Coolant temperatures as low as 22 °C were well tolerated continuously over three hours. CONCLUSION: Our results confirm the safety and tolerability of continuous flow limb hypothermia in healthy subjects. Further studies will use 22 °C thermoregulator temperature to investigate hypothermia in preventing CIPN in breast cancer patients receiving adjuvant weekly paclitaxel. This pilot study may contribute to alleviating chemotherapy dose limitation due to CIPN and increase the likelihood of success of chemotherapy.


Assuntos
Antineoplásicos/efeitos adversos , Hipotermia Induzida/métodos , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/prevenção & controle , Adulto , Braço , Humanos , Perna (Membro) , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Temperatura Cutânea , Adulto Jovem
15.
Muscle Nerve ; 52(1): 103-6, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25363084

RESUMO

INTRODUCTION: The cause of the double peak observed at submaximal stimulation of sensory nerves is unknown. The first peak is generated under the cathode and the second under the anode. The double peak is thought to arise from intradermal nerves or skin receptors, and in this study we tested this assumption. METHODS: We studied the effect of different stimulus durations on anodal peak latency in volunteers. Biphasic anodal stimulation was used to investigate the latent additive effect of the trailing negative phase on the partial depolarization induced by the initial positive phase. We further tested the maximal amplitude of anode-generated potentials to estimate the number of neural structures involved in their generation. RESULTS: Increased stimulus duration caused anode-generated potential delay. Biphasic stimulation increased anode-generated amplitude 4-fold compared with monophasic stimulation. The anode-generated potential produced up to 85% of the supramaximal cathode-generated amplitude. CONCLUSIONS: The results suggest that the double peak arises from anodal break excitation and not from intradermal nerves or receptors.


Assuntos
Fenômenos Biofísicos/fisiologia , Nervo Mediano/fisiologia , Condução Nervosa/fisiologia , Pele/inervação , Potenciais de Ação/fisiologia , Adulto , Estimulação Elétrica , Eletrodos , Eletromiografia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Tempo de Reação , Fatores de Tempo
16.
Brain Topogr ; 28(1): 135-52, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24878894

RESUMO

At the beginning of the twentieth century, many authors proposed that a considerable number of schizophrenic patients experience genuine motor abnormalities (GMA). In the era of antipsychotic treatment, GMA became a scientifically and clinically challenging characteristic of schizophrenia. Over the past 10 years, several magnetic resonance imaging (MRI) studies suggested a crucial role of the motor system in this disorder. Constituting a major relay center in the extrapyramidal motor system and being involved in the automatic execution of motor plans, an involvement of the basal ganglia with GMA and schizophrenia is plausible. However, the precise morphological correlates of GMA have remained controversial. The aim of this paper is to systematically review structural neuroimaging findings on GMA and basal ganglia in individuals with schizophrenia. Nineteen structural MRI studies were identified for inclusion in the review. Considering the extant data, there is some evidence for volumetric and shape alterations of basal ganglia in schizophrenia being in part determined by psychopathology and GMA, and not entirely explained by antipsychotic medication effects.


Assuntos
Gânglios da Base/patologia , Transtornos dos Movimentos/patologia , Esquizofrenia/patologia , Gânglios da Base/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Transtornos dos Movimentos/fisiopatologia , Esquizofrenia/fisiopatologia
17.
Muscle Nerve ; 47(1): 116-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23180630

RESUMO

INTRODUCTION: Doppler ultrasonography (DU) has recently been shown to be useful in imaging carpal tunnel syndrome (CTS). In this study, we aim to characterize the changes seen after exercise and electrical stimulation. METHODS: Five patients with CTS were recruited with 5 age-matched subjects. DU was used to visualize the median nerve, flexor tendon, and bone at base line and after 1 minute of: (a) median nerve motor stimulation, (b) median nerve sensory stimulation, (c) abductor pollicis brevis contraction, and (d) adductor digiti minimi contraction. RESULTS: Blood flow in the median nerve was greater after APB exercise. Furthermore, blood flow in the median nerve was greater in cases than controls after APB exercise. At baseline, blood flow in the flexor tendon was greater in cases than controls. CONCLUSIONS: While limited by sample size, this study demonstrates that exercise of median innervated muscles may be useful in enhancing diagnostic utility of DU for CTS.


Assuntos
Síndrome do Túnel Carpal/diagnóstico por imagem , Exercício Físico/fisiologia , Nervo Mediano/diagnóstico por imagem , Músculo Esquelético/diagnóstico por imagem , Nervo Ulnar/diagnóstico por imagem , Potenciais de Ação/fisiologia , Síndrome do Túnel Carpal/fisiopatologia , Estimulação Elétrica , Eletromiografia , Mãos/diagnóstico por imagem , Mãos/inervação , Mãos/fisiopatologia , Humanos , Nervo Mediano/fisiopatologia , Contração Muscular/fisiologia , Músculo Esquelético/inervação , Músculo Esquelético/fisiopatologia , Condução Nervosa/fisiologia , Nervo Ulnar/fisiopatologia , Ultrassonografia Doppler
18.
Biomed Eng Online ; 12: 120, 2013 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-24245952

RESUMO

BACKGROUND: Vascular hemodynamics is central to the regulation of neuro-metabolism and plays important roles in peripheral nerves diseases and their prevention. However, at present there are only a few techniques capable of directly measuring peripheral nerve vascular hemodynamics. METHOD: Here, we investigate the use of dark-field functional photoacoustic microscopy (fPAM) for intrinsic visualizing of the relative hemodynamics of the rat sciatic nerve in response to localized temperature modulation (i.e., cooling and rewarming). RESULTS AND CONCLUSION: Our main results show that the relative functional total hemoglobin concentration (HbT) is more significantly correlated with localized temperature changes than the hemoglobin oxygen saturation (SO2) changes in the sciatic nerve. Our study also indicates that the relative HbT changes are better markers of neuronal activation than SO2 during nerve temperature changes. Our results show that fPAM is a promising candidate for in vivo imaging of peripheral nerve hemodynamics without the use of contrast agents. Additionally, this technique may shed light on the neuroprotective effect of hypothermia on peripheral nerves by visualizing their intrinsic hemodynamics.


Assuntos
Hemodinâmica , Microscopia Confocal/métodos , Técnicas Fotoacústicas/métodos , Nervo Isquiático/fisiologia , Temperatura , Animais , Regulação da Temperatura Corporal/fisiologia , Feminino , Hemoglobinas/metabolismo , Oxigênio/metabolismo , Ratos , Ratos Wistar , Nervo Isquiático/metabolismo
19.
J Neurotrauma ; 40(9-10): 862-875, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36006372

RESUMO

Paresis after spinal cord injury (SCI) is caused by damage to upper and lower motoneurons (LMNs) and may differentially impact neurological recovery. This prospective monocentric longitudinal observational study investigated the extent and severity of LMN dysfunction and its impact on upper extremity motor recovery after acute cervical SCI. Pathological spontaneous activity at rest and/or increased discharge rates of motor unit action potentials recorded by needle electromyography (EMG) were taken as parameters for LMN dysfunction and its relation to the extent of myelopathy in the first available spine magnetic resonance imaging (MRI) was determined. Motor recovery was assessed by standardized neurological examination within the first four weeks (acute stage) and up to one year (chronic stage) after injury. Eighty-five muscles of 17 individuals with cervical SCI (neurological level of injury from C1 to C7) and a median age of 54 (28-59) years were examined. The results showed that muscles with signs of LMN dysfunction peaked at the lesion center (Χ2 [2, n = 85] = 6.6, p = 0.04) and that the severity of LMN dysfunction correlated with T2-weighted hyperintense MRI signal changes in routine spine MRI at the lesion site (Spearman ρ = 0.31, p = 0.01). Muscles exhibiting signs of LMN dysfunction, as indicated by pathological spontaneous activity at rest and/or increased discharge rates of motor unit action potentials, were associated with more severe paresis in both the acute and chronic stages after SCI (Spearman ρ acute = -0.22, p = 0.04 and chronic = -0.31, p = 0.004). Moreover, the severity of LMN dysfunction in the acute stage was also associated with a greater degree of paresis (Spearman ρ acute = -0.24, p = 0.03 and chronic = -0.35, p = 0.001). While both muscles with and without signs of LMN dysfunction were capable of regaining strength over time, those without LMN dysfunctions had a higher potential to reach full strength. Muscles with signs of LMN dysfunction in the acute stage displayed increased amplitudes of motor unit action potentials with chronic-stage needle EMG, indicating reinnervation through peripheral collateral sprouting as compensatory mechanism (Χ2 [1, n = 72] = 4.3, p = 0.04). Thus, LMN dysfunction represents a relevant factor contributing to motor impairment and recovery in acute cervical SCI. Defined recovery mechanisms (peripheral reinnervation) may at least partially underlie spontaneous recovery in respective muscles. Therefore, assessment of LMN dysfunction could help refine prediction of motor recovery after SCI.


Assuntos
Medula Cervical , Traumatismos da Medula Espinal , Humanos , Pessoa de Meia-Idade , Medula Cervical/diagnóstico por imagem , Estudos Prospectivos , Traumatismos da Medula Espinal/complicações , Eletromiografia/métodos , Neurônios Motores , Paresia
20.
Muscle Nerve ; 45(3): 434-5, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22334181

RESUMO

INTRODUCTION: Meralgia paresthetica can be difficult to diagnose, as neurophysiological studies are often hard to interpret due to excess fatty tissue and the varying anatomy of the lateral femoral cutaneous nerve. METHODS: We retrospectively analyzed the use of high-resolution ultrasound (HRU) for confirming clinical meralgia paresthetica and compared results with nerve conduction studies. RESULTS: In all 6 patients evaluated, HRUs showed significantly enlarged nerve diameter and in 3 enlarged cross-sectional area, 4 had absent nerve potentials, and in 2 the potentials could not be recorded on either side. CONCLUSIONS: HRU seems promising for confirming meralgia paresthetica and can accurately localize nerve entrapment.


Assuntos
Síndromes de Compressão Nervosa/diagnóstico por imagem , Ultrassonografia , Adulto , Eletromiografia , Feminino , Neuropatia Femoral , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Condução Nervosa/fisiologia , Exame Neurológico , Estudos Retrospectivos
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