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Abrahao A, Phung L, Fam D, Escorcio-Bezerra ML, Robinson LR, Jones KE, Zinman L. Motor Unit Number Index of the Upper Trapezius: A Meta-Analysis and Cross-sectional Study of Its Reliability. Can J Neurol Sci 2024; 51:129-133. [PMID: 36751865 DOI: 10.1017/cjn.2023.20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Motor unit number index of the upper trapezius (MUNIX-Trapezius) is a candidate biomarker for bulbar lower motor neuron function; however, reliability data is incomplete. To assess MUNIX-Trapezius reliability in controls, we conducted a systematic review, a cross-sectional study (n = 20), and a meta-analysis. We demonstrated a high inter- and intra-rater intraclass correlation (0.86 and 0.94, respectively), indicating that MUNIX-Trapezius is reliable with between-study variability moderated by age and MUNIX technique. With further validation, this measure can serve as a disease monitoring and response biomarker of bulbar function in the therapeutic development for amyotrophic lateral sclerosis.
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Affiliation(s)
- Agessandro Abrahao
- Division of Neurology, Department of Medicine, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
- Sunnybrook Research Institute, University of Toronto, Toronto, Ontario, Canada
| | - Liane Phung
- Sunnybrook Research Institute, University of Toronto, Toronto, Ontario, Canada
| | - David Fam
- St. Joseph's Health Centre Toronto, United Health, Toronto, Ontario, Canada
| | | | - Lawrence R Robinson
- Division of Physical Medicine and Rehabilitation, Department of Medicine, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
| | - Kelvin E Jones
- Faculty of Kinesiology, Sport and Recreation, University of Alberta, Edmonton, Alberta, Canada
| | - Lorne Zinman
- Division of Neurology, Department of Medicine, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
- Sunnybrook Research Institute, University of Toronto, Toronto, Ontario, Canada
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Liao SJ, Huang Z, Lai CY, Chen JY, Xiao PY, Cai Q, Yu J. The rostral to caudal gradient of clinical and electrophysiological features in sporadic amyotrophic lateral sclerosis with bulbar-onset. J Int Med Res 2021; 48:300060520956502. [PMID: 32993397 PMCID: PMC7536501 DOI: 10.1177/0300060520956502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Objective Amyotrophic lateral sclerosis (ALS) with bulbar-onset (BO-ALS) tends to
propagate to the adjacent anatomical regions symptomatically. However, the
spreading pattern of clinical and electrophysiological features is not well
documented. Methods This retrospective study enrolled consecutive patients with sporadic BO-ALS.
The clinical progression and electrophysiological data by electromyography
examination were retrospectively analysed based on information from the
medical records. Results The study enrolled 57 patients: 43 presented with contiguous (37 of 57) or
non-contiguous (6 of 57) progression clinically; and 14 patients did not
present with symptomatic propagation to other spinal segments. Lower motor
neuron dysfunction was more frequently involved in the bulbar and cervical
segments and less in the thoracic and lumbosacral segments. As a result, a
small proportion of patients had intact thoracic paraspinal or leg muscles
or both by electromyography examination. Furthermore, the patients with
diagnostic latency ≤6 months showed a significantly lower incidence of
neurogenic changes in the lumbosacral spinal cord compared with those with
diagnostic latency > 6 months. Conclusion This current study demonstrated a relative rostral–caudal descending gradient
of lower motor neuron dysfunction in patients with BO-ALS. These results
suggest that follow-up EMG might be necessary for a proportion of
patients.
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Affiliation(s)
- Song-Jie Liao
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University; Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangdong Provincial Engineering Center For Major Neurological Disease Treatment, Guangdong Provincial Translational Medicine Innovation Platform for Diagnosis and Treatment of Major Neurological Disease, Guangdong Provincial Clinical Research Center for Neurological Diseases, Guangzhou, China
| | - Zi Huang
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University; Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangdong Provincial Engineering Center For Major Neurological Disease Treatment, Guangdong Provincial Translational Medicine Innovation Platform for Diagnosis and Treatment of Major Neurological Disease, Guangdong Provincial Clinical Research Center for Neurological Diseases, Guangzhou, China
| | - Chong-Yuan Lai
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University; Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangdong Provincial Engineering Center For Major Neurological Disease Treatment, Guangdong Provincial Translational Medicine Innovation Platform for Diagnosis and Treatment of Major Neurological Disease, Guangdong Provincial Clinical Research Center for Neurological Diseases, Guangzhou, China
| | - Jing-Yan Chen
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University; Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangdong Provincial Engineering Center For Major Neurological Disease Treatment, Guangdong Provincial Translational Medicine Innovation Platform for Diagnosis and Treatment of Major Neurological Disease, Guangdong Provincial Clinical Research Center for Neurological Diseases, Guangzhou, China
| | - Pei-Yao Xiao
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University; Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangdong Provincial Engineering Center For Major Neurological Disease Treatment, Guangdong Provincial Translational Medicine Innovation Platform for Diagnosis and Treatment of Major Neurological Disease, Guangdong Provincial Clinical Research Center for Neurological Diseases, Guangzhou, China
| | - Qiong Cai
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University; Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangdong Provincial Engineering Center For Major Neurological Disease Treatment, Guangdong Provincial Translational Medicine Innovation Platform for Diagnosis and Treatment of Major Neurological Disease, Guangdong Provincial Clinical Research Center for Neurological Diseases, Guangzhou, China
| | - Jian Yu
- Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University; Guangdong Provincial Key Laboratory of Diagnosis and Treatment of Major Neurological Diseases, National Key Clinical Department and Key Discipline of Neurology, Guangdong Provincial Engineering Center For Major Neurological Disease Treatment, Guangdong Provincial Translational Medicine Innovation Platform for Diagnosis and Treatment of Major Neurological Disease, Guangdong Provincial Clinical Research Center for Neurological Diseases, Guangzhou, China
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3
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Bokuda K, Shimizu T, Kimura H, Morishima R, Kamiyama T, Kawata A, Nakayama Y, Isozaki E. Relationship between EMG-detected and ultrasound-detected fasciculations in amyotrophic lateral sclerosis: A prospective cohort study. Clin Neurophysiol 2019; 131:259-264. [PMID: 31506234 DOI: 10.1016/j.clinph.2019.08.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 08/12/2019] [Accepted: 08/16/2019] [Indexed: 12/12/2022]
Abstract
OBJECTIVES Fasciculation potentials (FP) are an important consideration in the electrophysiological diagnosis of ALS. Muscle ultrasonography (MUS) has a higher sensitivity in detecting fasciculations than electromyography (EMG), while in some cases, it is unable to detect EMG-detected fasciculations. We aimed to investigate the differences of FP between the muscles with and without MUS-detected fasciculations (MUS-fas). METHODS Thirty-one consecutive patients with sporadic ALS were prospectively recruited and in those, both needle EMG and MUS were performed. Analyses of the amplitude, duration, and number of phases of EMG-detected FPs were performed for seven muscles per patient, and results were compared between the muscles with and without MUS-fas in the total cohort. RESULTS The mean amplitude and phase number of FP were significantly lower in patients with EMG-detected FP alone (0.39 ± 0.25 mV and 3.21 ± 0.88, respectively) than in those with both FP and MUS-fas (1.22 ± 0.92 mV and 3.74 ± 1.39, respectively; p < 0.0001 and p = 0.017, Welch's t-test). CONCLUSION Small FP may be undetectable with MUS. MUS cannot replace EMG in the diagnostic approach for ALS. SIGNIFICANCE Clinicians should use a combination of EMG and MUS for the detection and quantitative analysis of fasciculation in ALS.
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Affiliation(s)
- Kota Bokuda
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan; ALS Nursing Care Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.
| | - Toshio Shimizu
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan; ALS Nursing Care Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Hideki Kimura
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
| | - Ryo Morishima
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
| | - Tsutomu Kamiyama
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
| | - Akihiro Kawata
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan; ALS Nursing Care Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Yuki Nakayama
- ALS Nursing Care Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Eiji Isozaki
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
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Menon P, Yiannikas C, Kiernan MC, Vucic S. Regional motor cortex dysfunction in amyotrophic lateral sclerosis. Ann Clin Transl Neurol 2019; 6:1373-1382. [PMID: 31402622 PMCID: PMC6689694 DOI: 10.1002/acn3.50819] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 05/17/2019] [Accepted: 05/17/2019] [Indexed: 12/11/2022] Open
Abstract
OBJECTIVE The pathophysiological processes underlying amyotrophic lateral sclerosis (ALS) need to be better understood, although cortical dysfunction has been implicated. Previous transcranial magnetic stimulation (TMS) studies have assessed cortical dysfunction from the hand. The aim of the present study was to determine whether cortical dysfunction was evident across representations of three body regions, and to relate these changes to clinical features of ALS. METHODS In this cross-sectional study, threshold tracking TMS was undertaken in 60 sporadic ALS patients, with motor evoked potential (MEP) responses recorded over the hand (abductor pollicis brevis), lower limb (tibialis anterior), and bulbar (trapezius) regions. The cross-sectional findings were compared to 28 age- and gender-matched controls. RESULTS Cortical dysfunction was evident across the representation of the three body regions, although the degree and nature of the dysfunction varied. Cortical hyperexcitability, as heralded by reduced short interval intracortical inhibition (SICI), was evident in all cortical regions (hand, P < 0.01; leg, P < 0.05; bulbar, P < 0.05) in ALS patients when compared with healthy control subjects. Importantly, features of cortical hyperexcitability seemed more prominent in clinically affected body regions and correlated with functional disability and muscle weakness. Cortical inexcitability was more prominent in the leg (P < 0.001) and bulbar regions (P < 0.01) when compared with controls. INTERPRETATION The nature of cortical dysfunction varied across the body regions in ALS, with cortical hyperexcitability being more prominent in the upper limbs while cortical inexcitability was more evident in the lower limbs and bulbar regions. The findings suggest a heterogeneity of cortical pathophysiological processes in ALS.
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Affiliation(s)
- Parvathi Menon
- Westmead HospitalSydneyNew South WalesAustralia
- University of SydneySydneyNew South WalesAustralia
| | - Con Yiannikas
- University of SydneySydneyNew South WalesAustralia
- Concord HospitalSydneyNew South WalesAustralia
| | - Matthew C. Kiernan
- University of SydneySydneyNew South WalesAustralia
- Brain and Mind InstituteSydneyNew South WalesAustralia
| | - Steve Vucic
- Westmead HospitalSydneyNew South WalesAustralia
- University of SydneySydneyNew South WalesAustralia
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5
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Amin Lari A, Ghavanini AA, Bokaee HR. A review of electrophysiological studies of lower motor neuron involvement in amyotrophic lateral sclerosis. Neurol Sci 2019; 40:1125-1136. [PMID: 30877611 DOI: 10.1007/s10072-019-03832-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 03/07/2019] [Indexed: 02/08/2023]
Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease involving both the upper and lower motor neuron diseases. In this review, we studied and compared different articles regarding the electrodiagnostic criteria for diagnosis of lower motor neuron pathology in ALS. We reviewed the most recent articles and metaanalysis regarding various lower motor neuron electrodiagnostic methods for ALS and their sensitivities. We concluded that Awaji Shima criteria is by far the most sensitive criteria for diagnosis of ALS.
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Affiliation(s)
- Ali Amin Lari
- Canadian Neurologic Center, Mississauga, ON, Canada.
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Zhang HG, Chen L, Tang L, Zhang N, Fan DS. Clinical Features of Isolated Bulbar Palsy of Amyotrophic Lateral Sclerosis in Chinese Population. Chin Med J (Engl) 2017; 130:1768-1772. [PMID: 28748847 PMCID: PMC5547826 DOI: 10.4103/0366-6999.211538] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Progressive bulbar palsy (PBP) is a classic phenotype of bulbar onset amyotrophic lateral sclerosis (ALS) with more rapid progression and worse prognosis. However, as an often under-understood variant of ALS, isolated bulbar palsy (IBP) appears to progress more slowly and has a relatively benign prognosis. This study aimed to investigate the natural course and clinical features of IBP in Chinese population and to compare them with those of PBP. METHODS The clinical data of patients with bulbar onset ALS were collected from January 2009 to December 2013. Revised ALS Functional Rating Scale (ALSFRS-R), forced vital capacity (FVC), and follow-up evaluation were performed, and the differences in basic clinical features, ALSFRS-R, FVC, and primary outcome measures between IBP and PBP were analyzed. The independent t-test, Chi-square test, Mann-Whitney U-test, and Kaplan-Meier analysis were used. RESULTS Totally 154 patients with bulbar onset ALS were categorized into two groups, 33 with IBP and 121 with PBP. In the IBP group, the male to female ratio was 0.7 to 1.0, and the mean onset age was 58.5 years. The mean duration from the onset was 16.0 months, and the mean ALSFRS-R score was 43.4 at patients' first visit to our hospital. In 14 IBP patients performing FVC examination, the mean FVC value was 90.5% and there were only two cases with abnormal FVC. In 26 IBP patients completing follow-up, 15 (58%) suffered death or tracheotomy and the mean survival time was 40.5 months. Significant differences were noted in sex ratio, onset age, ALSFRS-R score, upper motor neuron limb signs, pure lower motor neuron (LMN) bulbar signs, FVC, and survival time between IBP and PBP. CONCLUSIONS IBP was evidently different from PBP, which was characterized with the predominance of female, pure LMN bulbar signs, an older onset age, a relative preservation of respiratory function, and a better prognosis.
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Affiliation(s)
- Hua-Gang Zhang
- Department of Neurology, Peking University Third Hospital, Beijing 100191, China
| | - Lu Chen
- Department of Neurology, Peking University Third Hospital, Beijing 100191, China
| | - Lu Tang
- Department of Neurology, Peking University Third Hospital, Beijing 100191, China
| | - Nan Zhang
- Department of Neurology, Peking University Third Hospital, Beijing 100191, China
| | - Dong-Sheng Fan
- Department of Neurology, Peking University Third Hospital, Beijing 100191, China
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7
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Pan H, Jian F, Lin J, Chen N, Zhang Z, Wang Y, Cui L, Kimura J. Needle electromyography of the frontalis muscle in patients with amyotrophic lateral sclerosis. Muscle Nerve 2016; 54:1093-1096. [PMID: 27367360 DOI: 10.1002/mus.25236] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/30/2016] [Indexed: 12/13/2022]
Affiliation(s)
- Hua Pan
- Department of Neurology, Beijing Tiantan Hospital; Capital Medical University; Beijing 100050 China
| | - Fan Jian
- Department of Neurology, Beijing Tiantan Hospital; Capital Medical University; Beijing 100050 China
| | - Jinxi Lin
- Department of Neurology, Beijing Tiantan Hospital; Capital Medical University; Beijing 100050 China
| | - Na Chen
- Department of Neurology, Beijing Tiantan Hospital; Capital Medical University; Beijing 100050 China
| | - Zaiqiang Zhang
- Department of Neurology, Beijing Tiantan Hospital; Capital Medical University; Beijing 100050 China
| | - Yongjun Wang
- Department of Neurology, Beijing Tiantan Hospital; Capital Medical University; Beijing 100050 China
| | - Liying Cui
- Department of Neurology; Peking Union Medical College Hospital, Chinese Academy of Medical Science; Beijing China
| | - Jun Kimura
- Division of Clinical Electrophysiology, Department of Neurology, College of Medicine; University of Iowa; Iowa City Iowa USA
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8
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Bokuda K, Shimizu T, Kimura H, Yamazaki T, Kamiyama T, Watabe K, Kawata A, Hayashi M, Isozaki E. Quantitative analysis of the features of fasciculation potentials and their relation with muscle strength in amyotrophic lateral sclerosis. Neurol Sci 2016; 37:1939-1945. [PMID: 27541300 DOI: 10.1007/s10072-016-2692-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 08/16/2016] [Indexed: 12/26/2022]
Abstract
This study aimed to quantitatively analyze fasciculation potentials (FPs) and to investigate their relationship with muscle strength in amyotrophic lateral sclerosis (ALS). Fifty-one patients with sporadic ALS or progressive muscular atrophy (25 men, 26 women, mean age of 68 years) underwent needle EMG. We determined the duration, phase number, and amplitude of FPs from three muscles (upper trapezius, biceps brachii, and tibialis anterior) and examined their relations with muscle strength. In total, 878 FPs were analyzed. FP duration displayed a significant negative relation with the strength of all three muscles; the weaker muscles showed longer durations of FPs than the muscles with normal strength. The amplitude and phase number were not related with muscle strength, but there were significant correlations between the duration and amplitude of FPs in the trapezius and tibialis anterior muscles. The longer duration of FPs in muscles with weak strength suggests that the morphological changes of FPs were caused by temporal dispersion through progressively degenerating and/or immature reinnervating motor branches, and were observed uniformly in different muscles along with disease progression.
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Affiliation(s)
- Kota Bokuda
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, 2-6-1 Musashidai, Fuchu, Tokyo, 183-0042, Japan.,Mental Development Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Toshio Shimizu
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, 2-6-1 Musashidai, Fuchu, Tokyo, 183-0042, Japan.
| | - Hideki Kimura
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, 2-6-1 Musashidai, Fuchu, Tokyo, 183-0042, Japan
| | - Toshihiro Yamazaki
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, 2-6-1 Musashidai, Fuchu, Tokyo, 183-0042, Japan
| | - Tsutomu Kamiyama
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, 2-6-1 Musashidai, Fuchu, Tokyo, 183-0042, Japan
| | - Kazuhiko Watabe
- ALS and Neuropathy Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan.,Department of Medical Technology (Neuropathology), Kyorin University Faculty of Health Sciences, Tokyo, Japan
| | - Akihiro Kawata
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, 2-6-1 Musashidai, Fuchu, Tokyo, 183-0042, Japan
| | - Masaharu Hayashi
- Mental Development Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Eiji Isozaki
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, 2-6-1 Musashidai, Fuchu, Tokyo, 183-0042, Japan
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9
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New insights into the clinical neurophysiological assessment of ALS. Neurophysiol Clin 2016; 46:157-63. [PMID: 27364772 DOI: 10.1016/j.neucli.2016.05.070] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 05/25/2016] [Accepted: 05/25/2016] [Indexed: 12/11/2022] Open
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10
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Nichols NL, Van Dyke J, Nashold L, Satriotomo I, Suzuki M, Mitchell GS. Ventilatory control in ALS. Respir Physiol Neurobiol 2013; 189:429-37. [PMID: 23692930 DOI: 10.1016/j.resp.2013.05.016] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Revised: 05/13/2013] [Accepted: 05/13/2013] [Indexed: 12/11/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal, progressive neurodegenerative disease. ALS selectively causes degeneration in upper and lower (spinal) motor neurons, leading to muscle weakness, paralysis and death by ventilatory failure. Although ventilatory failure is generally the cause of death in ALS, little is known concerning the impact of this disorder on respiratory motor neurons, the consequences of respiratory motor neuron cell death, or the ability of the respiratory control system to "fight back" via mechanisms of compensatory respiratory plasticity. Here we review known effects of ALS on breathing, including possible effects on rhythm generation, respiratory motor neurons, and their target organs: the respiratory muscles. We consider evidence for spontaneous compensatory plasticity, preserving breathing well into disease progression despite dramatic loss of spinal respiratory motor neurons. Finally, we review current and potential therapeutic approaches directed toward preserving the capacity to breathe in ALS patients.
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Affiliation(s)
- Nicole L Nichols
- Department of Comparative Biosciences, University of Wisconsin, School of Veterinary Medicine, 2015 Linden Drive, Madison, WI 53706, USA
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