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1.
Artigo em Inglês | MEDLINE | ID: mdl-39137976

RESUMO

BACKGROUND: Cortical inexcitability, a less studied feature of upper motor neuron (UMN) dysfunction in amyotrophic lateral sclerosis (ALS), was identified in a large cross-sectional cohort of ALS patients and their demographic and clinical characteristics were contrasted with normal or hyperexcitable ALS cohorts to assess the impact of cortical inexcitability on ALS phenotype and survival. METHODS: Threshold-tracking transcranial magnetic stimulation (TMS) technique with measurement of mean short interval intracortical inhibition (SICI) differentiated ALS patients into three groups (1) inexcitable (no TMS response at maximal stimulator output in the setting of preserved lower motor neuron (LMN) function), (2) hyperexcitable (SICI≤5.5%) and (3) normal cortical excitability (SICI>5.5%). Clinical phenotyping and neurophysiological assessment of LMN function were undertaken, and survival was recorded in the entire cohort. RESULTS: 417 ALS patients were recruited, of whom 26.4% exhibited cortical inexcitability. Cortical inexcitability was associated with a younger age of disease onset (p<0.05), advanced Awaji criteria (p<0.01) and Kings stage (p<0.01) scores. Additionally, patients with cortical inexcitability had higher UMN score (p<0.01), lower revised ALS Functional Rating Scale score (p<0.01) and reduced upper limb strength score (MRC UL, p<0.01). Patient survival (p=0.398) was comparable across the groups, despite lower riluzole use in the cortical inexcitability patient group (p<0.05). CONCLUSION: The present study established that cortical inexcitability was associated with a phenotype characterised by prominent UMN signs, greater motor and functional decline, and a younger age of onset. The present findings inform patient management and could improve patient stratification in clinical trials.

2.
Eur J Neurol ; 31(7): e16281, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38504632

RESUMO

BACKGROUND AND PURPOSE: Cortical hyperexcitability has been identified as a diagnostic and pathogenic biomarker of amyotrophic lateral sclerosis (ALS). Cortical excitability is assessed by transcranial magnetic stimulation (TMS), a non-invasive neurophysiological technique. The TMS biomarkers exhibiting highest sensitivity for cortical hyperexcitability in ALS remain to be elucidated. A meta-analysis was performed to determine the TMS biomarkers exhibiting the highest sensitivity for cortical hyperexcitability in ALS. METHODS: A systematic literature review was conducted of all relevant studies published in the English language by searching PubMed, MEDLINE, Embase and Scopus electronic databases from 1 January 2006 to 28 February 2023. Inclusion criteria included studies reporting the utility of threshold tracking TMS (serial ascending method) in ALS and controls. RESULTS: In total, more than 2500 participants, incorporating 1530 ALS patients and 1102 controls (healthy, 907; neuromuscular, 195) were assessed with threshold tracking TMS across 25 studies. Significant reduction of mean short interval intracortical inhibition (interstimulus interval 1-7 ms) exhibited the highest standardized mean difference with moderate heterogeneity (-0.994, 95% confidence interval -1.12 to -0.873, p < 0.001; Q = 38.61, p < 0.05; I2 = 40%). The reduction of cortical silent period duration along with an increase in motor evoked potential amplitude and intracortical facilitation also exhibited significant, albeit smaller, standardized mean differences. CONCLUSION: This large meta-analysis study disclosed that mean short interval intracortical inhibition reduction exhibited the highest sensitivity for cortical hyperexcitability in ALS. Combined findings from this meta-analysis suggest that research strategies aimed at understanding the cause of inhibitory interneuronal circuit dysfunction could enhance understanding of ALS pathogenesis.


Assuntos
Esclerose Lateral Amiotrófica , Córtex Motor , Inibição Neural , Estimulação Magnética Transcraniana , Esclerose Lateral Amiotrófica/fisiopatologia , Humanos , Inibição Neural/fisiologia , Córtex Motor/fisiopatologia , Potencial Evocado Motor/fisiologia
3.
Neuropathology ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38558069

RESUMO

Argyrophilic grain disease (AGD) is one of the major pathological backgrounds of senile dementia. Dementia with grains refers to cases of dementia for which AGD is the sole background pathology responsible for dementia. Recent studies have suggested an association between dementia with grains and parkinsonism. In this study, we aimed to present two autopsy cases of dementia with grains. Case 1 was an 85-year-old man who exhibited amnestic dementia and parkinsonism, including postural instability, upward gaze palsy, and neck and trunk rigidity. The patient was clinically diagnosed with progressive supranuclear palsy and Alzheimer's disease. Case 2 was a 90-year-old man with pure amnestic dementia, clinically diagnosed as Alzheimer's disease. Recently, we used cryo-electron microscopy to confirm that the tau accumulated in both cases had the same three-dimensional structure. In this study, we compared the detailed clinical picture and neuropathological findings using classical staining and immunostaining methods. Both cases exhibited argyrophilic grains and tau-immunoreactive structures in the brainstem and basal ganglia, especially in the nigrostriatal and limbic systems. However, Case 1 had more tau immunoreactive structures. Considering the absence of other disease-specific structures such as tufted astrocytes, astrocytic plaques and globular glial inclusions, lack of conspicuous cerebrovascular disease, and no history of medications that could cause parkinsonism, our findings suggest an association between AGD in the nigrostriatal system and parkinsonism.

4.
Muscle Nerve ; 68(3): 257-263, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37086196

RESUMO

INTRODUCTION/AIMS: Reliable neurophysiological markers in amyotrophic lateral sclerosis (ALS) are of great interest. The compound muscle action potential (CMAP) amplitude has been a conventional marker, although it is greatly influenced by the electrode position. We propose the far-field potential of the CMAP (FFP-CMAP) as a new neurophysiological marker in ALS. METHODS: Patients with ALS and age-matched healthy controls were enrolled. We used a proximal reference (pref) in addition to the conventional distal reference (dref). Routine CMAP was recorded from the belly-dref lead and FFP-CMAP from the dref-pref lead for the ulnar and tibial nerves. Multiple point stimulation motor unit number estimation (MUNE) was also examined in the ulnar nerve. Inter-rater reproducibility was evaluated by two examiners, and some patients were followed up every 3 mo for 1 y. RESULTS: We tested 17 patients with ALS and 10 controls. The amplitudes of routine CMAP and FFP-CMAP in the ulnar and tibial nerves, and hypothenar MUNE value in the ulnar nerve were significantly decreased in ALS compared to controls. Ulnar FFP-CMAP achieved the highest inter-rater intraclass correlation coefficient (ICC) value (0.942) when compared with routine CMAP (0.880) and MUNE (0.839). The tibial FFP-CMAP had a higher ICC value (0.986) than the routine CMAP (0.697). In this way, the FFP-CMAP showed high inter-rater reproducibility because its shape was not much influenced by the electrode position. During 1-y follow-up, decline of CMAP, FFP, and MUNE showed significant correlations with the Amyotrophic Lateral Sclerosis Functional Rating Scale - Revised (ALSFRS-R). DISCUSSION: The FFP-CMAP shows promise as a reliable marker for ALS.


Assuntos
Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/diagnóstico , Neurônios Motores/fisiologia , Potenciais de Ação/fisiologia , Músculo Esquelético/fisiologia , Reprodutibilidade dos Testes
5.
J Neural Transm (Vienna) ; 130(4): 513-520, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36871130

RESUMO

Both cerebrospinal fluid (CSF) homovanillic acid (HVA) and striatal dopamine transporter (DAT) binding on single-photon emission computed tomography (SPECT) reflect nigrostriatal dopaminergic function, but studies on the relationship between the two have been limited. It is also unknown whether the reported variance in striatal DAT binding among diseases reflects the pathophysiology or characteristics of the subjects. We included 70 patients with Parkinson's disease (PD), 12 with progressive supranuclear palsy (PSP), 12 with multiple system atrophy, six with corticobasal syndrome, and nine with Alzheimer's disease as disease control, who underwent both CSF analysis and 123I-N-ω-fluoropropyl-2ß-carbomethoxy-3ß-(4-iodophenyl)nortropane (123I-ioflupane) SPECT. We evaluated the correlation between CSF HVA concentration and the specific binding ratio (SBR) of striatal DAT binding. We also compared the SBR for each diagnosis, controlling for CSF HVA concentration. The correlations between the two were significant in patients with PD (r = 0.34, p = 0.004) and PSP (r = 0.77, p = 0.004). The mean SBR value was the lowest in patients with PSP and was significantly lower in patients with PSP than in those with PD (p = 0.037) after adjusting for CSF HVA concentration. Our study demonstrates that striatal DAT binding correlates with CSF HVA concentration in both PD and PSP, and striatal DAT reduction would be more advanced in PSP than in PD at an equivalent dopamine level. Striatal DAT binding may correlate with dopamine levels in the brain. The pathophysiology of each diagnosis may explain this difference.


Assuntos
Doença de Parkinson , Transtornos Parkinsonianos , Humanos , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Ácido Homovanílico , Dopamina/metabolismo , Transtornos Parkinsonianos/diagnóstico por imagem , Transtornos Parkinsonianos/metabolismo , Tomografia Computadorizada de Emissão de Fóton Único/métodos
6.
Muscle Nerve ; 63(1): 89-95, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32997375

RESUMO

We previously reported a new quantitative analysis of single-channel surface electromyography (EMG), the "clustering index method" (CI method), in the tibialis anterior muscle, which achieved sufficiently good sensitivity to detect neurogenic or myogenic abnormalities. The window width is a fundamental parameter of the CI method, and was arbitrarily set at 15 ms in that study. In this study, we searched for the most appropriate window width using expanded patient data. The data from our previous study were reanalyzed, and new patients were enrolled. Window width in the CI method was changed from 5 to 27.5 ms with a step of 2.5 ms. For each window width, Z-score values of individual subjects were calculated and the diagnostic yield was investigated. We enrolled 67 controls, 29 subjects with neurogenic disorders, and 39 with myogenic disorders. When the window width was set at 22.5 ms, the highest sensitivity was achieved both for neurogenic (97%) and myogenic (72%) disorders, with a specificity of 97%. Seven of 10 patients with inclusion body myositis were also abnormal. Reliable results were obtained by collecting 15 epochs per subject. There are two conflicting effects that appear to be best balanced at a window width of 22.5 ms: a wider width decreases the chance that a motor unit potential (MUP) is divided into two adjacent windows, and a narrower width reduces the possibility that an MUP firing at a low-frequency is counted twice by the differential sequences. CI is promising as a non-invasive method to diagnose neuromuscular disorders.


Assuntos
Neurônios Motores/fisiologia , Músculo Esquelético/fisiopatologia , Miosite de Corpos de Inclusão/fisiopatologia , Doenças Neuromusculares/fisiopatologia , Adulto , Análise por Conglomerados , Eletromiografia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Neuromusculares/diagnóstico
7.
Eur J Neurol ; 28(4): 1172-1180, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33220162

RESUMO

AIM: Involvement of the corpus callosum has been identified as a feature of amyotrophic lateral sclerosis (ALS), particularly through neuropathological studies. The aim of the present study was to determine whether alteration in transcallosal function contributed to the development of ALS, disease progression and thereby functional disability. METHODS: Transcallosal function and motor cortex excitability were assessed in 17 ALS patients with results compared to healthy controls. Transcallosal inhibition (interstimulus intervals (ISI) of 8-40 ms), short interval intracortical facilitation (SICF) and inhibition (SICI) were assessed in both cerebral hemispheres. Patients were staged utilising clinical and neurophysiological staging assessments. RESULTS: In ALS, there was prominent reduction of transcallosal inhibition (TI) when recorded from the primary and secondary motor cortices compared to controls (F = 23.255, p < 0.001). This reduction of TI was accompanied by features indicative of cortical hyperexcitability, including reduction of SICI and increase in SICF. There was a significant correlation between the reduction in TI and the rate of disease progression (R = -0.825, p < 0.001) and reduction in muscle strength (R = 0.54, p = 0.031). CONCLUSION: The present study has established that dysfunction of transcallosal circuits was an important pathophysiological mechanism in ALS, correlating with greater disability and a faster rate of disease progression. Therapies aimed at restoring the function of transcallosal circuits may be considered for therapeutic approaches in ALS.


Assuntos
Esclerose Lateral Amiotrófica , Córtex Motor , Corpo Caloso , Potencial Evocado Motor , Humanos , Força Muscular , Inibição Neural , Estimulação Magnética Transcraniana
8.
Muscle Nerve ; 62(2): 192-200, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32077117

RESUMO

INTRODUCTION: We sought to evaluate the reproducibility of the motor unit number index (MUNIX) and MScanFit motor unit number estimation (MScan) when recording was performed over intrinsic hand muscles. METHODS: The compound muscle action potential (CMAP) amplitude, MUNIX, and MScan were measured from the abductor pollicis brevis (APB), first dorsal interosseous (FDI), and abductor digit minimi (ADM) muscles from 15 healthy volunteers on three different occasions. RESULTS: The reproducibility of CMAP amplitudes was excellent, with intraclass correlation coefficients (ICC) of 0.86 (APB), 0.90 (FDI), and 0.96 (ADM). Motor unit number index (ICCAPB 0.73, ICCFDI 0.85, ICCADM 0.85) and MScan (ICCAPB 0.86, ICCFDI 0.83, ICCADM 0.81) were highly reproducible across the three muscles. There were no significant correlations between MUNIX and MScan coefficients of variation (CV) and CMAP amplitude CVs. DISCUSSION: Reproducibility of MUNIX and MScan was not significantly different across the intrinsic hand muscles and was independent of CMAP amplitude variability.


Assuntos
Potenciais de Ação/fisiologia , Mãos , Neurônios Motores/fisiologia , Músculo Esquelético/fisiologia , Adulto , Eletromiografia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Neurônios Motores/citologia , Reprodutibilidade dos Testes
9.
Int J Mol Sci ; 20(11)2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31185581

RESUMO

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive and fatal neurodegenerative disorder of the motor neurons, characterized by focal onset of muscle weakness and incessant disease progression. While the presence of concomitant upper and lower motor neuron signs has been recognized as a pathognomonic feature of ALS, the pathogenic importance of upper motor neuron dysfunction has only been recently described. Specifically, transcranial magnetic stimulation (TMS) techniques have established cortical hyperexcitability as an important pathogenic mechanism in ALS, correlating with neurodegeneration and disease spread. Separately, ALS exhibits a heterogeneous clinical phenotype that may lead to misdiagnosis, particularly in the early stages of the disease process. Cortical hyperexcitability was shown to be a robust diagnostic biomarker if ALS, reliably differentiating ALS from neuromuscular mimicking disorders. The present review will provide an overview of key advances in the understanding of ALS pathophysiology and diagnosis, focusing on the importance of cortical hyperexcitability and its relationship to advances in genetic and molecular processes implicated in ALS pathogenesis.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico , Excitabilidade Cortical , Esclerose Lateral Amiotrófica/etiologia , Esclerose Lateral Amiotrófica/fisiopatologia , Eletroencefalografia/métodos , Humanos , Estimulação Magnética Transcraniana/métodos
10.
Muscle Nerve ; 58(5): 660-664, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30194855

RESUMO

INTRODUCTION: Reproducibility of the multiple point stimulation motor unit number estimation (MPS-MUNE) technique was compared with the recently developed motor unit number index (MUNIX) technique. METHODS: MPS-MUNE and MUNIX were performed on 15 healthy subjects at 3 different time-points by the same examiner. Reproducibility was analyzed using intraclass correlation coefficient (ICC) and coefficient of variation (CV). RESULTS: ICC values for MUNIX and MPS-MUNE were excellent across 3 tests (0.80 and 0.77, respectively), although CV values were significantly lower for MUNIX than MPS-MUNE (P < 0.01). In addition, test-retest reproducibility was better for MUNIX, a finding largely attributable to poor reproducibility of the single motor unit action potential area. MUNIX (R = -0.48, P < 0.05) and MPS-MUNE (R = -0.53, P < 0.05) were significantly correlated with age. DISCUSSION: MUNIX demonstrated better intrarater reproducibility and may be a more reliable neurophysiological biomarker than MPS-MUNE. Muscle Nerve 58: 660-664, 2018.


Assuntos
Potenciais de Ação/fisiologia , Neurônios Motores/fisiologia , Músculo Esquelético/fisiologia , Condução Nervosa/fisiologia , Recrutamento Neurofisiológico/fisiologia , Adulto , Idoso , Correlação de Dados , Estimulação Elétrica , Eletromiografia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores de Tempo , Nervo Ulnar/fisiologia
11.
Muscle Nerve ; 58(6): 824-827, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30019482

RESUMO

INTRODUCTION: Needle electromyography (EMG) has been an important diagnostic tool, although discomfort may limit its use in some children. We investigated the diagnostic utility of the clustering index (CI) method, a quantitative analysis for surface EMG (SEMG), in children. METHODS: SEMG was recorded from the tibialis anterior muscle. Discriminant analysis between patients with neurogenic disorders and patients with myopathy was performed for whole epochs by using the CI and area values. RESULTS: Forty-five children (29 with myopathy, 16 with neurogenic disorders; age 9 ± 3.9 years) were enrolled. The mean discriminant function value of the neurogenic group was 0.58 ± 0.88 (-0.48-2.30), whereas that of the myopathic group was -0.55 ± 0.70 (-2.38-0.68). When the cutoff value was set at the limit of the other group, 17 of 29 children with myopathy and 7 of 16 children with neurogenic disorders were correctly classified. DISCUSSION: The CI method can be a useful noninvasive diagnostic tool in children with neuromuscular disorders. Muscle Nerve 58:824-827, 2018.


Assuntos
Eletromiografia/métodos , Potencial Evocado Motor/fisiologia , Músculo Esquelético/fisiopatologia , Doenças Neuromusculares/diagnóstico , Doenças Neuromusculares/fisiopatologia , Adolescente , Criança , Pré-Escolar , Análise Discriminante , Feminino , Humanos , Lactente , Masculino
12.
Parkinsonism Relat Disord ; 128: 107129, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39241507

RESUMO

Cerebrospinal fluid (CSF) homovanillic acid (HVA) and 5-hydroxyindole acetic acid (5-HIAA), dopamine and serotonin metabolites, are decreased in Parkinson's disease (PD). Although some reported associations between HVA and striatal dopamine transporter (DAT) or 5-HIAA and cardiac 123I-meta-iodobenzylguanidine (MIBG) findings, respectively, whether these are direct associations remained unknown. We retrospectively reviewed 57 drug-naïve patients with PD who underwent CSF analyses and DAT and cardiac MIBG imaging. Z-score of striatal DAT specific binding ratio (Z-SBR) was measured, and the positivity of MIBG abnormalities were judged by an expert. The mean age was 75.5 ± 8.7 years. Thirty-three were MIBG-positive and 24 were MIBG-negative. 5-HIAA levels were significantly lower in the MIBG-positive group. Logistic regression analysis showed that MIBG positivity was associated with 5-HIAA level (odds ratio = 0.751, p = 0.006) but not with age, sex, and HVA. DAT Z-SBR correlated with both HVA and 5-HIAA. Multiple regression analysis showed that HVA was the only significant variable associated with Z-SBR (t = 3.510, p < 0.001). We confirmed direct associations between 5-HIAA and cardiac MIBG, and between HVA and striatal DAT binding.

13.
Geriatr Gerontol Int ; 24(7): 739-742, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38860537

RESUMO

An 81-year-old woman presented with statin-induced anti-HMGCR immune-mediated necrotizing myopathy. Treatment was successful without complications with a reduced oral steroid dosage from the current consensus for all ages and backgrounds. This case suggests the importance of early diagnosis and the possibility of steroid dosage adjustment considering the patient's age, disease severity, and comorbidities.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases , Doenças Musculares , Humanos , Feminino , Idoso de 80 Anos ou mais , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Doenças Musculares/tratamento farmacológico , Doenças Musculares/induzido quimicamente , Doenças Musculares/imunologia , Doenças Musculares/diagnóstico , Necrose , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Administração Oral , Hidroximetilglutaril-CoA Redutases/imunologia
14.
Clin Neurophysiol ; 163: 68-89, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38705104

RESUMO

Identifying upper motor neuron (UMN) dysfunction is fundamental to the diagnosis and understanding of disease pathogenesis in motor neuron disease (MND). The clinical assessment of UMN dysfunction may be difficult, particularly in the setting of severe muscle weakness. From a physiological perspective, transcranial magnetic stimulation (TMS) techniques provide objective biomarkers of UMN dysfunction in MND and may also be useful to interrogate cortical and network function. Single, paired- and triple pulse TMS techniques have yielded novel diagnostic and prognostic biomarkers in MND, and have provided important pathogenic insights, particularly pertaining to site of disease onset. Cortical hyperexcitability, as heralded by reduced short interval intracortical inhibition (SICI) and increased short interval intracortical facilitation, has been associated with the onset of lower motor neuron degeneration, along with patterns of disease spread, development of specific clinical features such as the split hand phenomenon, and may provide an indication about the rate of disease progression. Additionally, reduction of SICI has emerged as a potential diagnostic aid in MND. The triple stimulation technique (TST) was shown to enhance the diagnostic utility of conventional TMS measures in detecting UMN dysfunction in MND. Separately, sophisticated brain imaging techniques have uncovered novel biomarkers of neurodegeneration that have bene associated with progression. The present review will discuss the utility of TMS and brain neuroimaging derived biomarkers of UMN dysfunction in MND, focusing on recently developed TMS techniques and advanced neuroimaging modalities that interrogate structural and functional integrity of the corticomotoneuronal system, with an emphasis on pathogenic, diagnostic, and prognostic utility.


Assuntos
Esclerose Lateral Amiotrófica , Doença dos Neurônios Motores , Neurônios Motores , Estimulação Magnética Transcraniana , Humanos , Esclerose Lateral Amiotrófica/fisiopatologia , Esclerose Lateral Amiotrófica/diagnóstico , Estimulação Magnética Transcraniana/métodos , Doença dos Neurônios Motores/fisiopatologia , Doença dos Neurônios Motores/diagnóstico , Neurônios Motores/fisiologia , Potencial Evocado Motor/fisiologia , Córtex Motor/fisiopatologia , Córtex Motor/diagnóstico por imagem
15.
Muscle Nerve ; 48(2): 185-90, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23381960

RESUMO

INTRODUCTION: Far-field potentials (FFPs) from muscles other than the abductor digiti minimi (ADM) may interfere with motor unit number estimation (MUNE) from that muscle. METHODS: We identified the origin of each surface motor unit potential (SMUP) during hypothenar MUNE using the multiple point stimulation method in 20 control subjects by recording from individual ulnar-innervated muscles with a common proximal reference (pref). RESULTS: ADM SMUPs comprised 39.0% of the accepted SMUPs, followed by those from the fourth dorsal interosseous muscle (14.0%), the fourth lumbrical muscle (9.2%), and the second and third palmar interosseous muscles (8.8% each). The percentage of ADM SMUPs varied from 18% to 73% of accepted SMUPs among individual subjects. Accepted non-ADM SMUPs were usually much smaller than ADM SMUPs, and many more non-ADM SMUPs were excluded due to their small size. CONCLUSIONS: A large contribution from non-ADM or non-hypothenar SMUPs obscures the meaning of the MUNE value.


Assuntos
Potenciais de Ação/fisiologia , Mãos/inervação , Neurônios Motores/fisiologia , Músculo Esquelético/fisiologia , Adulto , Estimulação Elétrica , Eletrodos , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Muscle Nerve ; 48(2): 191-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23381934

RESUMO

INTRODUCTION: Contamination by far-field potentials (FFPs) may interfere with motor unit number estimation (MUNE) in the ulnar nerve. METHODS: Surface motor unit potentials (SMUPs) from 29 spinal and bulbar muscular atrophy (SBMA) patients and 27 control subjects were classified into SMUPs from the abductor digiti minimi muscle (ADM SMUPs) or non-ADM SMUPs, based on the waveform patterns from 3-channel recordings. RESULTS: The mean areas of the ADM SMUPs and non-ADM SMUPs in control subjects were 219.0 ± 131.3 and 63.7 ± 48.5 µVms, respectively. In SBMA patients they were 1988.9 ± 999.4 and 222.7 ± 125.7 µVms, respectively. The percentages of non-ADM SMUPs were 68 ± 22% in controls and 84 ± 15% in SBMA patients. CONCLUSIONS: Non-ADM SMUPs generated mainly by FFPs often had a negative onset in the routine lead and were indistinguishable from ADM SMUPs. More frequent exclusion of smaller non-ADM SMUPs in controls by size criteria would reduce the diagnostic yield of MUNE.


Assuntos
Potenciais de Ação/fisiologia , Mãos/inervação , Neurônios Motores/fisiologia , Músculo Esquelético/fisiologia , Nervo Ulnar/fisiologia , Adulto , Idoso , Estimulação Elétrica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Clin Nucl Med ; 48(10): 841-846, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37682599

RESUMO

BACKGROUND: 18F-THK5351 PET is used to image ongoing astrogliosis by estimating monoamine oxidase B levels. 18F-THK5351 preferentially accumulates around the substantia nigra (SN) and periaqueductal gray (PG) in the midbrain under healthy conditions and exhibits a "trimodal pattern." In progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS), the midbrain 18F-THK5351 uptake can be increased by astrogliosis, collapsing the "trimodal pattern." We aimed to elucidate cases in which the "trimodal pattern" collapses in PSP and CBS. PATIENTS AND METHODS: Participants in the PSP (n = 11), CBS (n = 17), Alzheimer disease (n = 11), and healthy control (n = 8) groups underwent 18F-THK5351 PET. Volumes of interest (VOIs) were placed on the SN, PG, and their midpoints. The midbrain uptake ratio (MUR) was calculated to assess the trimodal pattern as follows: MUR = (VOI value on the midpoint)/(VOI value on the SN and PG). Approximately, the trimodal pattern can be identified at MUR <1 but not at MUR >1. RESULTS: Compared with the healthy control group, MUR significantly increased in the PSP (P < 0.01) and CBS (P < 0.01) groups, but was unchanged in the Alzheimer disease group (P = 0.10). In the PSP group, all patients, including 2 with mild symptoms and a short disease duration, showed MUR >1. In the CBS group, MUR varied widely. CONCLUSIONS: In PSP, the trimodal pattern can collapse even in the early phase when symptoms are mild. In CBS, the trimodal pattern may or may not collapse depending on the underlying pathology.


Assuntos
Doença de Alzheimer , Degeneração Corticobasal , Paralisia Supranuclear Progressiva , Humanos , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Gliose , Mesencéfalo/diagnóstico por imagem
18.
Clin Case Rep ; 11(4): e7180, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37038534

RESUMO

Early diagnosis of spinal cord subacute combined degeneration (SCD) is difficult, especially in pre-existing lower extremity impairment cases. We report a case of progressive SCD diagnosed after severe anemia. The peripheral symptoms of SCD other than gait disturbance should also be well understood and given close attention.

19.
Clin Neurophysiol ; 156: 175-182, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37967511

RESUMO

OBJECTIVE: Utility of the split hand index (SI) in amyotrophic lateral sclerosis (ALS) has been reported when using the compound muscle action potential (CMAP) amplitude method (SICMAP amp). A motor unit number index (MUNIX) based SI method (SIMUNIX) was purported to exhibit higher sensitivity. The present study assessed the clinical utility of SI, derived by CMAP amplitude, MUNIX and MScan-MUNE (SIMScanFit-MUNE) methods, in ALS. METHODS: Sixty-two consecutive patients with neuromuscular symptoms (36 ALS and 26 ALS-mimics) were prospectively recruited. The SI was derived by dividing the product of the CMAP amplitude, MUNIX and MScan-MUNE values recorded over first dorsal interosseous and abductor pollicis brevis by values recorded over abductor digit minimi. RESULTS: SICMAP amp, SIMUNIX and SIMScanFit-MUNE were significantly reduced in ALS, with SICMAP amp (area under curve (AUC) = 0.801) and SIMScanFit-MUNE (AUC = 0.805) exhibiting greater diagnostic utility than SIMUNIX (AUC = 0.713). SICMAP amp and SIMScanFit-MUNE exhibited significant correlations with clinical measures of functional disability and weakness of intrinsic hand muscles. CONCLUSIONS: SI differentiated ALS from mimic disorders, with SICMAP amp and SIMScanFit-MUNE exhibiting greater utility. SIGNIFICANCE: The split hand index represents could serve as a potential diagnostic biomarker in ALS.


Assuntos
Esclerose Lateral Amiotrófica , Humanos , Esclerose Lateral Amiotrófica/diagnóstico , Músculo Esquelético , Mãos , Área Sob a Curva , Potenciais de Ação/fisiologia , Eletromiografia/métodos
20.
Sci Rep ; 13(1): 12147, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37500734

RESUMO

Corticobasal syndrome (CBS) is characterized by symptoms related to the asymmetric involvement of the cerebral cortex and basal ganglia. However, early detection of asymmetric imaging abnormalities can be challenging. Previous studies reported asymmetric 18F-THK5351 PET abnormalities in CBS patients, but the sensitivity for detecting such abnormalities in larger patient samples, including early-stage cases, remains unclear. Patients clinically diagnosed with CBS were recruited. All patients displayed asymmetric symptoms in the cerebral cortex and basal ganglia. Asymmetric THK5351 PET abnormalities were determined through visual assessment. Brain MRI, perfusion SPECT, and dopamine transporter (DAT) SPECT results were retrospectively reviewed. The 15 patients had a median age of 72 years (59-86 years) and a disease duration of 2 years (0.5-7 years). Four patients met the probable and 11 met the possible CBS criteria according to Armstrong criteria at the time of PET examination. All patients, including early-stage cases, exhibited asymmetric tracer uptake contralateral to their symptom-dominant side in the cerebral cortex/subcortical white matter and striatum (100%). The sensitivity for detecting asymmetric imaging abnormalities contralateral to the symptom-dominant side was 86.7% for brain MRI, 81.8% for perfusion SPECT, and 90% for DAT SPECT. White matter volume reduction was observed in the subcortical region of the precentral gyrus with increased THK5351 uptake, occurring significantly more frequently than gray matter volume reduction. THK5351 PET may be a sensitive imaging technique for detecting asymmetric CBS pathologies, including those in early stages.


Assuntos
Degeneração Corticobasal , Humanos , Idoso , Encéfalo/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Estudos Retrospectivos , Compostos Radiofarmacêuticos
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