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Belvisi D, Leodori G, Costanzo M, Conte A, Berardelli A. How does botulinum toxin really work? INTERNATIONAL REVIEW OF NEUROBIOLOGY 2023; 169:441-479. [PMID: 37482400 DOI: 10.1016/bs.irn.2023.05.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/25/2023]
Abstract
Over the past 30 years, Botulinum toxin (BoNT) has emerged as an effective and safe therapeutic tool for a number of neurological conditions, including dystonia. To date, the exact mechanism of action of BoNT in dystonia is not fully understood. Although it is well known that BoNT mainly acts on the neuromuscular junction, a growing body of evidence suggests that the therapeutic effect of BoNT in dystonia may also depend on its ability to modulate peripheral sensory feedback from muscle spindles. Animal models also suggest a retrograde and anterograde BoNT transportation from the site of injection to central nervous system structures. In humans, however, BoNT central effects seem to depend on the modulation of afferent input rather than on BoNT transportation. In this chapter, we aimed to report and discuss research evidence providing information on the possible mechanisms of action of BoNT in relation to treatment of dystonia.
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Affiliation(s)
- Daniele Belvisi
- Department of Human Neurosciences, Sapienza, University of Rome, Viale dell' Università 30, Rome, Italy; IRCCS Neuromed, via Atinense 18, Pozzilli, IS, Italy
| | - Giorgio Leodori
- Department of Human Neurosciences, Sapienza, University of Rome, Viale dell' Università 30, Rome, Italy; IRCCS Neuromed, via Atinense 18, Pozzilli, IS, Italy
| | | | - Antonella Conte
- Department of Human Neurosciences, Sapienza, University of Rome, Viale dell' Università 30, Rome, Italy; IRCCS Neuromed, via Atinense 18, Pozzilli, IS, Italy
| | - Alfredo Berardelli
- Department of Human Neurosciences, Sapienza, University of Rome, Viale dell' Università 30, Rome, Italy; IRCCS Neuromed, via Atinense 18, Pozzilli, IS, Italy.
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2
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Sanuki T. Spasmodic dysphonia: An overview of clinical features and treatment options. Auris Nasus Larynx 2023; 50:17-22. [PMID: 35697560 DOI: 10.1016/j.anl.2022.05.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Revised: 05/06/2022] [Accepted: 05/19/2022] [Indexed: 01/28/2023]
Abstract
Spasmodic dysphonia (SD) is considered a rare focal laryngeal dystonia characterized by task-specific voice dysfluency resulting from selective intrinsic laryngeal musculature hyperfunction. Symptoms may be attenuated by a sensory trick. Although SD can be seen at times in generalized dystonia syndrome, it is typically a sporadic phenomenon, and the involvement of the laryngeal adductor muscles is more common than that of the abductor muscles. This research reviews the literature for the pathogenesis, clinical characteristics, treatment options, and current management methods of SD. Technological advances have enabled clinicians to better understand the connection between laryngeal function and dysfunction. Refinements in imaging and genetic investigation techniques have helped better understand the underlying mechanisms of this neurolaryngology disorder. Currently, the standard of care for SD is the symptomatic management of botulinum toxin (BT) chemodenervation. This is supported by a large body of literature attesting to its efficacy in many different research studies, particularly in the uncomplicated adductor form of the disorder. Efforts towards surgical treatment predate the development of BT treatment by a decade, but the long-term efficacy has not been proven and, further research is expected. Symptom relief in patients with abductor SD and dystonia with tremors after surgical and BT treatments and those in patients remains suboptimal.
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Affiliation(s)
- Tetsuji Sanuki
- Department of Otolaryngology-Head and Neck Surgery, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi Mizuho-Cho, Mizuho-Ku, Nagoya, Japan.
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Botulinum Toxin Intervention in Cerebral Palsy-Induced Spasticity Management: Projected and Contradictory Effects on Skeletal Muscles. Toxins (Basel) 2022; 14:toxins14110772. [PMID: 36356022 PMCID: PMC9692445 DOI: 10.3390/toxins14110772] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 10/22/2022] [Accepted: 11/04/2022] [Indexed: 11/09/2022] Open
Abstract
Spasticity, following the neurological disorder of cerebral palsy (CP), describes a pathological condition, the central feature of which is involuntary and prolonged muscle contraction. The persistent resistance of spastic muscles to stretching is often followed by structural and mechanical changes in musculature. This leads to functional limitations at the respective joint. Focal injection of botulinum toxin type-A (BTX-A) is effectively used to manage spasticity and improve the quality of life of the patients. By blocking acetylcholine release at the neuromuscular junction and causing temporary muscle paralysis, BTX-A aims to reduce spasticity and hereby improve joint function. However, recent studies have indicated some contradictory effects such as increased muscle stiffness or a narrower range of active force production. The potential of these toxin- and atrophy-related alterations in worsening the condition of spastic muscles that are already subjected to changes should be further investigated and quantified. By focusing on the effects of BTX-A on muscle biomechanics and overall function in children with CP, this review deals with which of these goals have been achieved and to what extent, and what can await us in the future.
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Hok P, Veverka T, Hluštík P, Nevrlý M, Kaňovský P. The Central Effects of Botulinum Toxin in Dystonia and Spasticity. Toxins (Basel) 2021; 13:155. [PMID: 33671128 PMCID: PMC7922085 DOI: 10.3390/toxins13020155] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 02/02/2021] [Accepted: 02/11/2021] [Indexed: 12/05/2022] Open
Abstract
In dystonic and spastic movement disorders, however different in their pathophysiological mechanisms, a similar impairment of sensorimotor control with special emphasis on afferentation is assumed. Peripheral intervention on afferent inputs evokes plastic changes within the central sensorimotor system. Intramuscular application of botulinum toxin type A (BoNT-A) is a standard evidence-based treatment for both conditions. Apart from its peripheral action on muscle spindles, a growing body of evidence suggests that BoNT-A effects could also be mediated by changes at the central level including cerebral cortex. We review recent studies employing electrophysiology and neuroimaging to investigate how intramuscular application of BoNT-A influences cortical reorganization. Based on such data, BoNT-A becomes gradually accepted as a promising tool to correct the maladaptive plastic changes within the sensorimotor cortex. In summary, electrophysiology and especially neuroimaging studies with BoNT-A further our understanding of pathophysiology underlying dystonic and spastic movement disorders and may consequently help develop novel treatment strategies based on neural plasticity.
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Affiliation(s)
| | - Tomáš Veverka
- Department of Neurology, Faculty of Medicine and Dentistry, University Hospital Olomouc, Palacký University Olomouc, 779 00 Olomouc, Czech Republic; (P.H.); (P.H.); (M.N.); (P.K.)
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Poydasheva AG, Semenova OV, Suponeva NA, Timerbaeva SL, Piradov MA. [Issues of diagnostic and therapeutic use of transcranial magnetic stimulation in patients with writing cramp]. Zh Nevrol Psikhiatr Im S S Korsakova 2021; 120:49-56. [PMID: 33459541 DOI: 10.17116/jnevro202012012149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To study diagnostic and therapeutic values of transcranial magnetic stimulation (TMS) in writing cramp (WC). MATERIAL AND METHODS Twelve right-handed patients with WC were enrolled in the study. All patients underwent low-frequency repetitive TMS (rTMS) of the premotor cortex of contralateral to affected hand hemisphere. The clinical efficacy was assessed using the Writer's Cramp Rating Scale (WCRS) and the Medical Outcomes Study-Short Form (MOS-SF-36). Before and after last rTMS session, motor mapping of Abductor pollicis brevis muscle (APB) was performed using navigated TMS (nTMS). Localization, area, and amplitude-weighted area of the APB muscle cortical representations were compared with the healthy controls. After the rTMS course, the dynamics of the studied parameters was assessed. RESULTS Ten sessions of low-frequency rTMS of premotor cortex reduced the severity of WS clinical symptoms with a duration of effect of at least 1 month (p<0.05). There was no statistically significant difference between the area and the weighted area of cortical muscle representations between patients and healthy controls or in patients before and after rTMS. When assessing the localization of cortical muscle representations, two trends were noted: in 4 patients, the localization remained stable, with a shift in the center of gravity of less than 4 mm; in the other 8 patients, a shift in the center of mass of more than 5 mm was noted. No significant correlation between the stability of the cortical muscle representations (the magnitude of the shift in the center of gravity) and the improvement on the WCRS were found. CONCLUSION The low-frequency rTMS of the premotor cortex of the contralateral to affected hand hemisphere can be used as an adjuvant therapy for WC. The TMS-motor mapping study did not show its diagnostic value.
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Affiliation(s)
| | - O V Semenova
- Vorokhobov City Clinical Hospital No. 67, Moscow, Russia
| | | | | | - M A Piradov
- Research Center of Neurology, Moscow, Russia
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Zoghi M, Hafezi P, Amatya B, Khan F, Galea MP. Intracortical Circuits in the Contralesional Primary Motor Cortex in Patients With Chronic Stroke After Botulinum Toxin Type A Injection: Case Studies. Front Hum Neurosci 2020; 14:342. [PMID: 33100987 PMCID: PMC7497670 DOI: 10.3389/fnhum.2020.00342] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 08/03/2020] [Indexed: 11/22/2022] Open
Abstract
Spasticity and motor recovery are both related to neural plasticity after stroke. A balance of activity in the primary motor cortex (M1) in both hemispheres is essential for functional recovery. In this study, we assessed the intracortical inhibitory and facilitatory circuits in the contralesional M1 area in four patients with severe upper limb spasticity after chronic stroke and treated with botulinum toxin-A (BoNT-A) injection and 12 weeks of upper limb rehabilitation. There was little to no change in the level of spasticity post-injection, and only one participant experienced a small improvement in arm function. All reported improvements in quality of life. However, the levels of intracortical inhibition and facilitation in the contralesional hemisphere were different at baseline for all four participants, and there was no clear pattern in the response to the intervention. Further investigation is needed to understand how BoNT-A injections affect inhibitory and facilitatory circuits in the contralesional hemisphere, the severity of spasticity, and functional improvement.
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Affiliation(s)
- Maryam Zoghi
- Department of Physiotherapy, Podiatry, Prosthetics and Orthotics, La Trobe University, Melbourne, VIC, Australia
| | | | - Bhasker Amatya
- The Royal Melbourne Hospital, Melbourne, VIC, Australia.,University of Melbourne, Melbourne, VIC, Australia
| | - Fary Khan
- The Royal Melbourne Hospital, Melbourne, VIC, Australia.,University of Melbourne, Melbourne, VIC, Australia
| | - Mary Pauline Galea
- The Royal Melbourne Hospital, Melbourne, VIC, Australia.,University of Melbourne, Melbourne, VIC, Australia
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Watanabe T, Nojima I, Mima T, Sugiura H, Kirimoto H. Magnification of visual feedback modulates corticomuscular and intermuscular coherences differently in young and elderly adults. Neuroimage 2020; 220:117089. [DOI: 10.1016/j.neuroimage.2020.117089] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 06/05/2020] [Accepted: 06/21/2020] [Indexed: 10/24/2022] Open
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Strzalkowski NDJ, Sondergaard RE, Gan LS, Kiss ZHT. Case studies in neuroscience: deep brain stimulation changes upper limb cortical motor maps in dystonia. J Neurophysiol 2020; 124:268-273. [PMID: 32579422 DOI: 10.1152/jn.00159.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Deep brain stimulation of the globus pallidus pars interna (GPi-DBS) is an effective treatment for primary dystonia; however, its therapeutic mechanism is poorly understood. Because improvement is gradual, GPi-DBS treatment likely involves short- and long-term mechanisms. Abnormal plasticity resulting in somatotopic reorganization is involved in the development of dystonia and has been proposed as a possible mechanism for this gradual improvement, yet it has not been directly investigated. We hypothesized that GPi-DBS will lead to progressive changes in the cortical representations (motor maps) of upper limb muscles. Neuronavigated robotic transcranial magnetic stimulation was used to map the cortical representation of five upper limb muscles in six healthy controls and a 45-yr-old female cervical dystonia patient before (Pre) and at four time points (Post5 to Post314), 5 to 314 days after GPi-DBS. Motor map area and volume decreased in all muscles following GPi-DBS, while changes in overlap and center of gravity distance between muscles were variable. Despite these motor map changes, only dystonic tremor improved after a year of DBS; neck position worsened slightly. These preliminary findings suggest that GPi-DBS may reduce the cortical representation and excitability of upper limb muscles in dystonia and that these changes can occur without clinical improvement.NEW & NOTEWORTHY Neuronavigated robotic transcranial magnetic stimulation was used to investigate changes in upper limb muscle representation in a cervical dystonia patient before and at four time points up to 314 days after globus pallidus pars interna deep brain stimulation (GPi-DBS). GPi-DBS altered excitability and motor cortical representation of upper limb muscles; however, these changes were not associated with clinical improvement.
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Affiliation(s)
- Nicholas D J Strzalkowski
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Departments of Biology and General Education, Mount Royal University, Calgary, Alberta, Canada
| | - Rachel E Sondergaard
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Liu Shi Gan
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Zelma H T Kiss
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
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De Bartolo MI, Manzo N, Ferrazzano G, Baione V, Belvisi D, Fabbrini G, Berardelli A, Conte A. Botulinum Toxin Effects on Sensorimotor Integration in Focal Dystonias. Toxins (Basel) 2020; 12:toxins12050277. [PMID: 32344856 PMCID: PMC7290883 DOI: 10.3390/toxins12050277] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 04/22/2020] [Accepted: 04/23/2020] [Indexed: 12/04/2022] Open
Abstract
(1) Background: In dystonia, the somatosensory temporal discrimination threshold (STDT) is abnormally increased at rest and higher and longer-lasting during movement execution in comparison with healthy subjects (HS), suggesting an abnormal sensorimotor integration. These abnormalities are thought to depend on abnormal proprioceptive input coming from dystonic muscles. Since Botulinum toxin-A (BT-A) reduces proprioceptive input in the injected muscles, our study investigated the effects of BT-A on STDT tested at rest and during voluntary movement execution in patients with focal dystonia. (2) Methods: We enrolled 35 patients with focal dystonia: 14 patients with cervical dystonia (CD), 11 patients with blepharospasm (BSP), and 10 patients with focal hand dystonia (FHD); and 12 age-matched HS. STDT tested by delivering paired stimuli was measured in all subjects at rest and during index finger abductions. (3) Results: Patients with dystonia had higher STDT values at rest and during movement execution than HS. While BT-A did not modify STDT at rest, it reduced the abnormal values of STDT during movement in CD and FHD patients, but not in BSP patients. (4) Conclusions: BT-A improved abnormal sensorimotor integration in CD and FHD, most likely by decreasing the overflow of proprioceptive signaling from muscle dystonic activity to the thalamus.
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Affiliation(s)
- Maria Ilenia De Bartolo
- IRCCS NEUROMED, Via Atinense, 18, 86077 Pozzilli (IS), Italy; (M.I.D.B.); (N.M.); (D.B.); (G.F.); (A.C.)
| | - Nicoletta Manzo
- IRCCS NEUROMED, Via Atinense, 18, 86077 Pozzilli (IS), Italy; (M.I.D.B.); (N.M.); (D.B.); (G.F.); (A.C.)
| | - Gina Ferrazzano
- Department of Human Neuroscience, Sapienza University of Rome, 00185 Rome, Italy; (G.F.); (V.B.)
| | - Viola Baione
- Department of Human Neuroscience, Sapienza University of Rome, 00185 Rome, Italy; (G.F.); (V.B.)
| | - Daniele Belvisi
- IRCCS NEUROMED, Via Atinense, 18, 86077 Pozzilli (IS), Italy; (M.I.D.B.); (N.M.); (D.B.); (G.F.); (A.C.)
| | - Giovanni Fabbrini
- IRCCS NEUROMED, Via Atinense, 18, 86077 Pozzilli (IS), Italy; (M.I.D.B.); (N.M.); (D.B.); (G.F.); (A.C.)
- Department of Human Neuroscience, Sapienza University of Rome, 00185 Rome, Italy; (G.F.); (V.B.)
| | - Alfredo Berardelli
- IRCCS NEUROMED, Via Atinense, 18, 86077 Pozzilli (IS), Italy; (M.I.D.B.); (N.M.); (D.B.); (G.F.); (A.C.)
- Department of Human Neuroscience, Sapienza University of Rome, 00185 Rome, Italy; (G.F.); (V.B.)
- Correspondence:
| | - Antonella Conte
- IRCCS NEUROMED, Via Atinense, 18, 86077 Pozzilli (IS), Italy; (M.I.D.B.); (N.M.); (D.B.); (G.F.); (A.C.)
- Department of Human Neuroscience, Sapienza University of Rome, 00185 Rome, Italy; (G.F.); (V.B.)
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Poydasheva AG, Semenova OV, Suponeva NA, Timerbaeva SL, Piradov MA. [Diagnostic and therapeutic issues of using transcranial magnetic stimulation in patients with writer's cramp]. Zh Nevrol Psikhiatr Im S S Korsakova 2019; 119:22-29. [PMID: 31793539 DOI: 10.17116/jnevro201911910122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
AIM To assess diagnostic and therapeutic values of transcranial magnetic stimulation (TMS) in patients with writer's cramp (WC). MATERIAL AND METHODS Twelve right-handed patients with WC were enrolled in the study. All patients underwent low-frequency repetitive TMS (rTMS) over the premotor cortex of the hemisphere contralateral to the affected hand. The clinical efficacy was assessed using the Writer's Cramp Rating Scale (WCRS) and the Medical Outcomes Study-Short Form (MOS-SF-36). Before and after the last rTMS session, motor mapping of abductor pollicis brevis muscle (APB) was performed using navigated TMS (nTMS). Localization, area, and amplitude-weighted area of the APB muscle cortical representations were compared with the healthy controls. The dynamics of the mentioned above parameters after the rTMS course was assessed. RESULTS Ten sessions of low-frequency rTMS over premotor cortex reduced the severity of WC clinical symptoms, with a duration of effect of at least 1 month (p<0.05). There was no significant difference between the area and the weighted area of cortical muscle representations between patients and healthy controls or in patients before and after rTMS. When assessing the localization of cortical muscle representations, two trends were noted: in 4 patients, the localization remained stable, with a shift in the center of gravity of less than 4 mm; in the other 8 patients, a shift in the center of gravity of more than 5 mm was noted. No significant correlations between the stability of the cortical muscle representations (the magnitude of the shift in the center of gravity) and the improvement on the WCRS scale were found. CONCLUSION The low-frequency rTMS over the premotor cortex of the hemisphere contralateral to the affected hand can be used as an adjuvant therapy for WC. The TMS-motor mapping study did not show its diagnostic value.
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Affiliation(s)
| | - O V Semenova
- Vorokhobov City Clinical Hospital #67, Moscow, Russia
| | | | - S L Timerbaeva
- Federal State Hospital for Treatment and Rehabilitation, Moscow, Russia
| | - M A Piradov
- Research Center of Neurology, Moscow, Russia
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Chirumamilla VC, Dresel C, Koirala N, Gonzalez-Escamilla G, Deuschl G, Zeuner KE, Muthuraman M, Groppa S. Structural brain network fingerprints of focal dystonia. Ther Adv Neurol Disord 2019; 12:1756286419880664. [PMID: 31798688 PMCID: PMC6859688 DOI: 10.1177/1756286419880664] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 09/10/2019] [Indexed: 01/02/2023] Open
Abstract
Background: Focal dystonias are severe and disabling movement disorders of a still unclear origin. The structural brain networks associated with focal dystonia have not been well characterized. Here, we investigated structural brain network fingerprints in patients with blepharospasm (BSP) compared with those with hemifacial spasm (HFS), and healthy controls (HC). The patients were also examined following treatment with botulinum neurotoxin (BoNT). Methods: This study included matched groups of 13 BSP patients, 13 HFS patients, and 13 HC. We measured patients using structural-magnetic resonance imaging (MRI) at baseline and after one month BoNT treatment, at time points of maximal and minimal clinical symptom representation, and HC at baseline. Group regional cross-correlation matrices calculated based on grey matter volume were included in graph-based network analysis. We used these to quantify global network measures of segregation and integration, and also looked at local connectivity properties of different brain regions. Results: The networks in patients with BSP were more segregated than in patients with HFS and HC (p < 0.001). BSP patients had increased connectivity in frontal and temporal cortices, including sensorimotor cortex, and reduced connectivity in the cerebellum, relative to both HFS patients and HC (p < 0.05). Compared with HC, HFS patients showed increased connectivity in temporal and parietal cortices and a decreased connectivity in the frontal cortex (p < 0.05). In BSP patients, the connectivity of the frontal cortex diminished after BoNT treatment (p < 0.05). In contrast, HFS patients showed increased connectivity in the temporal cortex and reduced connectivity in cerebellum after BoNT treatment (p < 0.05). Conclusions: Our results show that BSP patients display alterations in both segregation and integration in the brain at the network level. The regional differences identified in the sensorimotor cortex and cerebellum of these patients may play a role in the pathophysiology of focal dystonia. Moreover, symptomatic reduction of hyperkinesia by BoNT treatment was associated with different brain network fingerprints in both BSP and HFS patients.
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Affiliation(s)
- Venkata C Chirumamilla
- Movement Disorders and Neurostimulation, Biomedical Statistics and Multimodal Signal Processing Unit, Department of Neurology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Christian Dresel
- Movement Disorders and Neurostimulation, Biomedical Statistics and Multimodal Signal Processing Unit, Department of Neurology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Nabin Koirala
- Movement Disorders and Neurostimulation, Biomedical Statistics and Multimodal Signal Processing Unit, Department of Neurology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Gabriel Gonzalez-Escamilla
- Movement Disorders and Neurostimulation, Biomedical Statistics and Multimodal Signal Processing Unit, Department of Neurology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Günther Deuschl
- Department of Neurology, University Hospital Schleswig-Holstein, University of Kiel, Kiel, Schleswig-Holstein, Germany
| | - Kirsten E Zeuner
- Department of Neurology, University Hospital Schleswig-Holstein, University of Kiel, Kiel, Schleswig-Holstein, Germany
| | - Muthuraman Muthuraman
- Movement Disorders and Neurostimulation, Biomedical Statistics and Multimodal Signal Processing Unit, Department of Neurology, Focus Program Translational Neuroscience (FTN), University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Sergiu Groppa
- Movement Disorders and Neurostimulation, Department of Neurology, Focus Program Translational Neuroscience (FTN), Rhine-Main Neuroscience network (rmn), Johannes-Gutenberg-University Mainz, Langenbeckstr. 1, Mainz, 55131, Germany
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Desrochers P, Brunfeldt A, Sidiropoulos C, Kagerer F. Sensorimotor Control in Dystonia. Brain Sci 2019; 9:brainsci9040079. [PMID: 30979073 PMCID: PMC6523253 DOI: 10.3390/brainsci9040079] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 04/03/2019] [Accepted: 04/08/2019] [Indexed: 12/24/2022] Open
Abstract
This is an overview of the sensorimotor impairments in dystonia, a syndrome characterized by sustained or intermittent aberrant movement patterns leading to abnormal movements and/or postures with or without a tremulous component. Dystonia can affect the entire body or specific body regions and results from a plethora of etiologies, including subtle changes in gray and white matter in several brain regions. Research over the last 25 years addressing topics of sensorimotor control has shown functional sensorimotor impairments related to sensorimotor integration, timing, oculomotor and head control, as well as upper and lower limb control. In the context of efforts to update the classification of dystonia, sensorimotor research is highly relevant for a better understanding of the underlying pathology, and potential mechanisms contributing to global and regional dysfunction within the central nervous system. This overview of relevant research regarding sensorimotor control in humans with idiopathic dystonia attempts to frame the dysfunction with respect to what is known regarding motor control in patients and healthy individuals. We also highlight promising avenues for the future study of neuromotor control that may help to further elucidate dystonia etiology, pathology, and functional characteristics.
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Affiliation(s)
- Phillip Desrochers
- Dept. of Kinesiology, Michigan State University, East Lansing, MI 48824, USA.
| | - Alexander Brunfeldt
- Dept. of Kinesiology, Michigan State University, East Lansing, MI 48824, USA.
| | - Christos Sidiropoulos
- Dept. of Neurology and Ophthalmology, Michigan State University, East Lansing, MI 48824, USA.
| | - Florian Kagerer
- Dept. of Kinesiology, Michigan State University, East Lansing, MI 48824, USA.
- Neuroscience Program, Michigan State University, East Lansing, MI 48824, USA.
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Brodoehl S, Wagner F, Prell T, Klingner C, Witte OW, Günther A. Cause or effect: Altered brain and network activity in cervical dystonia is partially normalized by botulinum toxin treatment. NEUROIMAGE-CLINICAL 2019; 22:101792. [PMID: 30928809 PMCID: PMC6444302 DOI: 10.1016/j.nicl.2019.101792] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 03/14/2019] [Accepted: 03/24/2019] [Indexed: 01/17/2023]
Abstract
Background Idiopathic cervical dystonia (CD) is a chronic movement disorder characterized by impressive clinical symptoms and the lack of clear pathological findings in clinical diagnostics and imaging. At present, the injection of botulinum toxin (BNT) in dystonic muscles is an effective therapy to control motor symptoms and pain in CD. Objectives We hypothesized that, although it is locally injected to dystonic muscles, BNT application leads to changes in brain and network activity towards normal brain function. Methods Using 3 T functional MR imaging along with advanced analysis techniques (functional connectivity, Granger causality, and regional homogeneity), we aimed to characterize brain activity in CD (17 CD patients vs. 17 controls) and to uncover the effects of BNT treatment (at 6 months). Results In CD, we observed an increased information flow within the basal ganglia, the thalamus, and the sensorimotor cortex. In parallel, some of these structures became less responsive to regulating inputs. Furthermore, our results suggested an altered somatosensory integration. Following BNT administration, we noted a shift towards normal brain function in the CD patients, especially within the motor cortex, the somatosensory cortex, and the basal ganglia. Conclusion The changes in brain function and network activity in CD can be interpreted as related to the underlying cause, the effort to compensate or a mixture of both. Although BNT is applied in the last stage of the cortico-neuromuscular pathway, brain patterns are shifted towards those of healthy controls. we characterized brain activity in CD and the effects of BNT using 3T fMR imaging and network analysis techniques following treatment with botulinum toxin (BNT), abnormal brain activity patterns in primary dystonia are attenuated critical key regions for both the pathophysiology and BNT-induced improvement in cervical dystonia are the BG
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Affiliation(s)
- Stefan Brodoehl
- Hans Berger Department for Neurology, Friedrich Schiller University of Jena, Germany; Brain Imaging Center, Friedrich Schiller University Jena, Germany.
| | - Franziska Wagner
- Hans Berger Department for Neurology, Friedrich Schiller University of Jena, Germany; Brain Imaging Center, Friedrich Schiller University Jena, Germany
| | - Tino Prell
- Hans Berger Department for Neurology, Friedrich Schiller University of Jena, Germany; Center for Healthy Aging, Jena University Hospital, Jena, Germany
| | - Carsten Klingner
- Hans Berger Department for Neurology, Friedrich Schiller University of Jena, Germany; Brain Imaging Center, Friedrich Schiller University Jena, Germany
| | - O W Witte
- Hans Berger Department for Neurology, Friedrich Schiller University of Jena, Germany; Brain Imaging Center, Friedrich Schiller University Jena, Germany; Center for Healthy Aging, Jena University Hospital, Jena, Germany
| | - Albrecht Günther
- Hans Berger Department for Neurology, Friedrich Schiller University of Jena, Germany
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Central Effects of Botulinum Neurotoxin-Evidence from Human Studies. Toxins (Basel) 2019; 11:toxins11010021. [PMID: 30621330 PMCID: PMC6356587 DOI: 10.3390/toxins11010021] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 12/25/2018] [Accepted: 12/31/2018] [Indexed: 11/24/2022] Open
Abstract
For more than three decades, Botulinum neurotoxin (BoNT) has been used to treat a variety of clinical conditions such as spastic or dystonic disorders by inducing a temporary paralysis of the injected muscle as the desired clinical effect. BoNT is known to primarily act at the neuromuscular junction resulting in a biochemical denervation of the treated muscle. However, recent evidence suggests that BoNT’s pharmacological properties may not only be limited to local muscular denervation at the injection site but may also include additional central effects. In this review, we report and discuss the current evidence for BoNT’s central effects based on clinical observations, neurophysiological investigations and neuroimaging studies in humans. Collectively, these data strongly point to indirect mechanisms via changes to sensory afferents that may be primarily responsible for the marked plastic effects of BoNT on the central nervous system. Importantly, BoNT-related central effects and consecutive modulation and/or reorganization of the brain may not solely be considered “side-effects” but rather an additional therapeutic impact responsible for a number of clinical observations that cannot be explained by merely peripheral actions.
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Abstract
We review the motor cortical and basal ganglia involvement in two important movement disorders: Parkinson's disease (PD) and dystonia. Single and paired pulse transcranial magnetic stimulation studies showed altered excitability and cortical circuits in PD with decreased silent period, short interval intracortical inhibition, intracortical facilitation, long afferent inhibition, interhemispheric inhibition, and cerebellar inhibition, and increased long interval intracortical inhibition and short interval intracortical facilitation. In dystonia, there is decreased silent period, short interval intracortical inhibition, long afferent inhibition, interhemispheric inhibition, and increased intracortical facilitation. Plasticity induction protocols revealed deficient plasticity in PD and normal and exaggerated plasticity in dystonia. In the basal ganglia, there is increased β (14-30Hz) rhythm in PD and characteristic 5-18Hz band synchronization in dystonia. These motor cortical circuits, cortical plasticity, and oscillation profiles of the basal ganglia are altered with medications and deep brain stimulation treatment. There is considerable variability in these measures related to interindividual variations, different disease characteristics, and methodological considerations. Nevertheless, these pathophysiologic studies have expanded our knowledge of cortical excitability, plasticity, and oscillations in PD and dystonia, improved our understanding of disease pathophysiology, and helped to develop new treatments for these conditions.
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Affiliation(s)
- Kaviraja Udupa
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Bangalore, India
| | - Robert Chen
- Division of Neurology, Department of Medicine, University of Toronto, Toronto, ON, Canada.
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16
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Abstract
Dystonias are characterized by involuntary muscle contractions, twisting movements, abnormal postures, and often tremor in various body regions. However, in the last decade several studies have demonstrated that dystonias are also characterized by sensory abnormalities. While botulinum toxin is the gold standard therapy for focal dystonia, exactly how it improves this disorder is not entirely understood. Neurophysiological studies in animals and humans have clearly demonstrated that botulinum toxin improves dystonic motor manifestations by inducing chemodenervation, therefore weakening the injected muscles. In addition, neurophysiological and neuroimaging evidence also suggests that botulinum toxin modulates the activity of various neural structures in the CNS distant from the injected site, particularly cortical motor and sensory areas. Concordantly, recent studies have shown that in patients with focal dystonias botulinum toxin ameliorates sensory disturbances, including reduced spatial discrimination acuity and pain. Overall, these observations suggest that in these patients botulinum toxin-induced effects encompass complex mechanisms beyond chemodenervation of the injected muscles.
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Affiliation(s)
- Alfredo Berardelli
- Department of Human Neurosciences, Sapienza University of Rome, Rome, Italy.
- IRCCS Neuromed, Pozzilli, IS, Italy.
| | - Antonella Conte
- Department of Human Neurosciences, Sapienza University of Rome, Rome, Italy
- IRCCS Neuromed, Pozzilli, IS, Italy
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Kesar TM, Stinear JW, Wolf SL. The use of transcranial magnetic stimulation to evaluate cortical excitability of lower limb musculature: Challenges and opportunities. Restor Neurol Neurosci 2018; 36:333-348. [PMID: 29758954 DOI: 10.3233/rnn-170801] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Neuroplasticity is a fundamental yet relatively unexplored process that can impact rehabilitation of lower extremity (LE) movements. Transcranial magnetic stimulation (TMS) has gained widespread application as a non-invasive brain stimulation technique for evaluating neuroplasticity of the corticospinal pathway. However, a majority of TMS studies have been performed on hand muscles, with a paucity of TMS investigations focused on LE muscles. This perspective review paper proposes that there are unique methodological challenges associated with using TMS to evaluate corticospinal excitability of lower limb muscles. The challenges include: (1) the deeper location of the LE motor homunculus; (2) difficulty with targeting individual LE muscles during TMS; and (3) differences in corticospinal circuity controlling upper and lower limb muscles. We encourage future investigations that modify traditional methodological approaches to help address these challenges. Systematic TMS investigations are needed to determine the extent of overlap in corticomotor maps for different LE muscles. A simple, yet informative methodological solution involves simultaneous recordings from multiple LE muscles, which will provide the added benefit of observing how other relevant muscles co-vary in their responses during targeted TMS assessment directed toward a specific muscle. Furthermore, conventionally used TMS methods (e.g., determination of hot spot location and motor threshold) may need to be modified for TMS studies involving LE muscles. Additional investigations are necessary to determine the influence of testing posture as well as activation state of adjacent and distant LE muscles on TMS-elicited responses. An understanding of these challenges and solutions specific to LE TMS will improve the ability of neurorehabilitation clinicians to interpret TMS literature, and forge novel future directions for neuroscience research focused on elucidating neuroplasticity processes underlying locomotion and gait training.
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Affiliation(s)
- Trisha M Kesar
- Department of Rehabilitation Medicine, Division of Physical Therapy, Emory University, Atlanta, GA, USA
| | - James W Stinear
- Exercise Sciences, The University of Auckland, Auckland, New Zealand
| | - Steven L Wolf
- Department of Rehabilitation Medicine, Division of Physical Therapy, Emory University, Atlanta, GA, USA.,Center for Visual and Neurocognitive Rehabilitation, Atlanta Veterans Affair Medical Center, Decatur, GA, USA
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Garside T, Wood FM, Vallence AM. Case series investigating the cortical silent period after burns using transcranial magnetic stimulation. Burns 2018; 44:1195-1202. [DOI: 10.1016/j.burns.2018.04.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 03/02/2018] [Accepted: 04/10/2018] [Indexed: 12/25/2022]
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19
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Testing rTMS-Induced Neuroplasticity: A Single Case Study of Focal Hand Dystonia. Neural Plast 2018; 2018:6464896. [PMID: 30002674 PMCID: PMC5998194 DOI: 10.1155/2018/6464896] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Accepted: 04/30/2018] [Indexed: 11/18/2022] Open
Abstract
Focal hand dystonia in musicians is a neurological motor disorder in which aberrant plasticity is caused by excessive repetitive use. This work's purposes were to induce plasticity changes in a dystonic musician through five daily thirty-minute sessions of 1 Hz repetitive transcranial magnetic stimulation (rTMS) applied to the left M1 by using neuronavigated stimulation and to reliably measure the effect of these changes. To this aim, the relationship between neuroplasticity changes and motor recovery was investigated using fine-grained kinematic analysis. Our results suggest a statistically significant improvement in motor coordination both in a task resembling the dystonic-inducing symptoms and in a reach-to-grasp task. This single case study supports the safe and effective use of noninvasive brain stimulation in neurologic patients and highlights the importance of evaluating outcomes in measurable ways. This issue is a key aspect to focus on to classify the clinical expression of dystonia. These preliminary results promote the adoption of kinematic analysis as a valuable diagnostic tool.
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Caverzasio S, Amato N, Manconi M, Prosperetti C, Kaelin-Lang A, Hutchison WD, Galati S. Brain plasticity and sleep: Implication for movement disorders. Neurosci Biobehav Rev 2018; 86:21-35. [DOI: 10.1016/j.neubiorev.2017.12.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 12/15/2017] [Accepted: 12/18/2017] [Indexed: 12/31/2022]
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21
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Blitzer A, Brin MF, Simonyan K, Ozelius LJ, Frucht SJ. Phenomenology, genetics, and CNS network abnormalities in laryngeal dystonia: A 30-year experience. Laryngoscope 2018; 128 Suppl 1:S1-S9. [PMID: 29219190 PMCID: PMC5757628 DOI: 10.1002/lary.27003] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 09/23/2017] [Accepted: 10/16/2017] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Laryngeal dystonia (LD) is a functionally specific disorder of the afferent-efferent motor coordination system producing action-induced muscle contraction with a varied phenomenology. This report of long-term studies aims to review and better define the phenomenology and central nervous system abnormalities of this disorder and improve diagnosis and treatment. METHODS Our studies categorized over 1,400 patients diagnosed with LD over the past 33 years, including demographic and medical history records and their phenomenological presentations. Patients were grouped on clinical phenotype (adductor or abductor) and genotype (sporadic and familial) and with DNA analysis and functional magnetic resonance imaging (fMRI) to investigate brain organization differences and characterize neural markers for genotype/phenotype categorization. A number of patients with alcohol-sensitive dystonia were also studied. RESULTS A spectrum of LD phenomena evolved: adductor, abductor, mixed, singer's, dystonic tremor, and adductor respiratory dystonia. Patients were genetically screened for DYT (dystonia) 1, DYT4, DYT6, and DYT25 (GNAL)-and several were positive. The functional MRI studies showed distinct alterations within the sensorimotor network, and the LD patients with a family history had distinct cortical and cerebellar abnormalities. A linear discriminant analysis of fMRI findings showed a 71% accuracy in characterizing LD from normal and in characterizing adductor from abductor forms. CONCLUSION Continuous studies of LD patients over 30 years has led to an improved understanding of the phenomenological characteristics of this neurological disorder. Genetic and fMRI studies have better characterized the disorder and raise the possibility of making objective rather than subjective diagnoses, potentially leading to new therapeutic approaches. Laryngoscope, 128:S1-S9, 2018.
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Affiliation(s)
- Andrew Blitzer
- Dept of Otolaryngology-Head and Neck Surgery, Columbia University, College of Physicians and Surgeons
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School
- New York Center for Voice and Swallowing Disorders
| | | | - Kristina Simonyan
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School
- Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Harvard Medical School
| | | | - Steven J Frucht
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School
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22
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Jochim A, Li Y, Gora-Stahlberg G, Mantel T, Berndt M, Castrop F, Dresel C, Haslinger B. Altered functional connectivity in blepharospasm/orofacial dystonia. Brain Behav 2018; 8:e00894. [PMID: 29568690 PMCID: PMC5853618 DOI: 10.1002/brb3.894] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 11/08/2017] [Accepted: 11/15/2017] [Indexed: 12/16/2022] Open
Abstract
INTRODUCTION Blepharospasm is characterized by involuntary eyelid spasms. It can be associated with perioral dystonia (Meige's syndrome or orofacial dystonia). We aimed at studying resting-state functional brain connectivity in these patients and its potential modulation by therapeutic botulinum toxin injections. METHODS We performed resting-state functional MRI and a region of interest-based analysis of functional connectivity in 13 patients with blepharospasm/Meige's syndrome in comparison to 13 healthy controls. Patients were studied before and 4 weeks after botulinum toxin treatment. Simultaneous facial electromyography was applied to control for involuntary facial movements. RESULTS Before botulinum toxin treatment, patients showed reduced functional connectivity between caudate and primary sensorimotor, somatosensory association and visual cortices as well as between putamen and parietal association cortex. Cerebellar areas displayed decreased functional connectivity to somatosensory and visual association cortices. On the cortical level, connectivity was reduced between the cingulate cortex and the primary sensorimotor/premotor and parietal association cortex, between premotor areas and the primary somatosensory cortices, and between the postcentral gyrus and temporoparietal, secondary somatosensory, cingular, and cerebellar regions. Botulinum toxin treatment modulated functional connectivity, especially between cerebellum and visual cortices. CONCLUSIONS Patients with blepharospasm/Meige's syndrome show altered functional connectivity at rest in widespread brain regions including basal ganglia, cerebellar, primary/secondary sensorimotor, and visual areas. Functionally, this may reflect a predisposition for defective movement inhibition and sensorimotor integration. Botulinum toxin treatment could modulate brain connectivity in blepharospasm by altering visual and sensory input.
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Affiliation(s)
- Angela Jochim
- Department of Neurology Klinikum rechts der Isar Technische Universität München Munich Germany
| | - Yong Li
- Department of Neurology Klinikum rechts der Isar Technische Universität München Munich Germany
| | - Gina Gora-Stahlberg
- Department of Neurology Klinikum rechts der Isar Technische Universität München Munich Germany
| | - Tobias Mantel
- Department of Neurology Klinikum rechts der Isar Technische Universität München Munich Germany
| | - Maria Berndt
- Department of Neurology Klinikum rechts der Isar Technische Universität München Munich Germany.,Department of Neuroradiology Klinikum rechts der Isar Technische Universität München Munich Germany
| | - Florian Castrop
- Department of Neurology Klinikum rechts der Isar Technische Universität München Munich Germany.,Department of Neurology and Neurologic Rehabilitation Asklepios Stadtklinik Bad TölzBad Tölz Germany
| | - Christian Dresel
- Department of Neurology Klinikum rechts der Isar Technische Universität München Munich Germany.,Department of Neurology School of Medicine Johannes Gutenberg University Mainz Germany
| | - Bernhard Haslinger
- Department of Neurology Klinikum rechts der Isar Technische Universität München Munich Germany
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Caleo M, Restani L. Direct central nervous system effects of botulinum neurotoxin. Toxicon 2017; 147:68-72. [PMID: 29111119 DOI: 10.1016/j.toxicon.2017.10.027] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 10/24/2017] [Accepted: 10/26/2017] [Indexed: 12/29/2022]
Abstract
Local intramuscular injections of botulinum neurotoxin type A (BoNT/A) are effective in the treatment of focal dystonias, muscle spasms, and spasticity. However, not all clinical effects of BoNT/A may be explained by its action at peripheral nerve terminals. For example, the therapeutic benefit may exceed the duration of the peripheral neuroparalysis induced by the neurotoxin. In cellular and animal models, evidence demonstrates retrograde transport of catalytically active BoNT/A in projection neurons. This process of long-range trafficking is followed by transcytosis and action at second-order synapses. In humans, several physiological changes have been described following intramuscular delivery of BoNT/A. In particular, clinical studies have documented a decrease in Renshaw cell-mediated inhibition (i.e., recurrent inhibition), which may be important therapeutically for normalizing uncoordinated movements and overflow of muscle activity. In this review, we present data obtained in animal and experimental models that support direct central actions of BoNT/A mediated via retrograde axonal trafficking. We also discuss the reorganization of central circuitry induced by BoNT/A in patients, and the potential contribution of these effects to the therapeutic efficacy of the neurotoxin.
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Affiliation(s)
- Matteo Caleo
- CNR Neuroscience Institute, via G. Moruzzi 1, 56124, Pisa, Italy
| | - Laura Restani
- CNR Neuroscience Institute, via G. Moruzzi 1, 56124, Pisa, Italy.
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24
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Hallett M. Mechanism of action of botulinum neurotoxin: Unexpected consequences. Toxicon 2017; 147:73-76. [PMID: 28803760 DOI: 10.1016/j.toxicon.2017.08.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2017] [Accepted: 08/08/2017] [Indexed: 01/23/2023]
Abstract
Botulinum neurotoxin (BoNT) is a widely used therapeutic in part because its mechanism of action is much wider than initially expected. Since BoNT is taken up more avidly in active presynaptic terminals, there is some selectivity for weakening muscles involved in frequent involuntary movements. BoNT blocks gamma motoneurons as well as alpha motoneurons, hence reducing afferent spindle activity which appears to have a favorable effect. Some BoNT is retrogradely transported in the motor axons, leading at least to reduction in recurrent inhibition mediated by the Renshaw cell. There are also central nervous system changes after BoNT injections and these may be due to brain plasticity.
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Affiliation(s)
- Mark Hallett
- Human Motor Control Section, NINDS, NIH, Bethesda, United States.
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Ward S, Bryant AL, Pietrosimone B, Bennell KL, Clark R, Pearce AJ. Cortical motor representation of the rectus femoris does not differ between the left and right hemisphere. J Electromyogr Kinesiol 2016; 28:46-52. [PMID: 26999234 DOI: 10.1016/j.jelekin.2016.03.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 02/16/2016] [Accepted: 03/07/2016] [Indexed: 11/25/2022] Open
Abstract
Transcranial magnetic stimulation (TMS) involves non-invasive magnetic stimulation of the brain, and can be used to explore the corticomotor excitability and motor representations of skeletal muscles. However there is a lack of motor mapping studies in the lower limb and few conducted in healthy cohorts. The cortical motor representations of muscles can vary between individuals in terms of center position and area despite having a general localized region within the motor cortex. It is important to characterize the normal range for these variables in healthy cohorts to be able to evaluate changes in clinical populations. TMS was used in this cross-sectional study to assess the active motor threshold (AMT) and cortical representation area for rectus femoris in 15 healthy individuals (11M/4F 27.3±5.9years). No differences were found between hemispheres (Left vs. Right P=0.130) for AMT. In terms of y-axis center position no differences were found between hemispheres (Left vs. Right P=0.539), or for the x-axis center position (Left vs. Right P=0.076). Similarly, no differences in calculated area of the motor representation were found (Left vs. Right P=0.699) indicating symmetry between hemispheres.
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Affiliation(s)
- Sarah Ward
- Centre for Health, Exercise and Sports Medicine, Department of Physiotherapy, Faculty of Medicine, Dentistry and Health Science, University of Melbourne, VIC, Australia.
| | - Adam L Bryant
- Centre for Health, Exercise and Sports Medicine, Department of Physiotherapy, Faculty of Medicine, Dentistry and Health Science, University of Melbourne, VIC, Australia
| | - Brian Pietrosimone
- Department of Exercise and Sport Science, University of North Carolina at Chapel Hill, NC, United States
| | - Kim L Bennell
- Centre for Health, Exercise and Sports Medicine, Department of Physiotherapy, Faculty of Medicine, Dentistry and Health Science, University of Melbourne, VIC, Australia
| | - Ross Clark
- School of Exercise Science, Australian Catholic University, VIC, Australia
| | - Alan J Pearce
- Centre for Health, Exercise and Sports Medicine, Department of Physiotherapy, Faculty of Medicine, Dentistry and Health Science, University of Melbourne, VIC, Australia
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Veverka T, Hluštík P, Hok P, Otruba P, Zapletalová J, Tüdös Z, Krobot A, Kaňovský P. Sensorimotor modulation by botulinum toxin A in post-stroke arm spasticity: Passive hand movement. J Neurol Sci 2016; 362:14-20. [PMID: 26944111 DOI: 10.1016/j.jns.2015.12.049] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Revised: 12/08/2015] [Accepted: 12/31/2015] [Indexed: 11/26/2022]
Abstract
INTRODUCTION In post-stroke spasticity, functional imaging may uncover modulation in the central sensorimotor networks associated with botulinum toxin type A (BoNT) therapy. Investigations were performed to localize brain activation changes in stroke patients treated with BoNT for upper limb spasticity using functional magnetic resonance imaging (fMRI). METHODS Seven ischemic stroke patients (4 females; mean age 58.86) with severe hand paralysis and notable spasticity were studied. Spasticity was scored according to the modified Ashworth scale (MAS). fMRI examination was performed 3 times: before (W0) and 4 (W4) and 11weeks (W11) after BoNT. The whole-brain fMRI data were acquired during paced repetitive passive movements of the plegic hand (flexion/extension at the wrist) alternating with rest. Voxel-by-voxel statistical analysis using the General Linear Model (GLM) implemented in FSL (v6.00)/FEAT yielded group session-wise statistical maps and paired between-session contrasts, thresholded at the corrected cluster-wise significance level of p<0.05. RESULTS As expected, BoNT transiently lowered MAS scores at W4. Across all the sessions, fMRI activation of the ipsilesional sensorimotor cortex (M1, S1, and SMA) dominated. At W4, additional clusters transiently emerged bilaterally in the cerebellum, in the contralesional sensorimotor cortex, and in the contralesional occipital cortex. Paired contrasts demonstrated significant differences W4>W0 (bilateral cerebellum and contralesional occipital cortex) and W4>W11 (ipsilesional cerebellum and SMA). The remaining paired contrast (W0>W11) showed activation decreases mainly in the ipsilesional sensorimotor cortex (M1, S1, and SMA). CONCLUSIONS The present study confirms the feasibility of using passive hand movements to map the cerebral sensorimotor networks in patients with post-stroke arm spasticity and demonstrates that BoNT-induced spasticity relief is associated with changes in task-induced central sensorimotor activation, likely mediated by an altered afferent drive from the spasticity-affected muscles.
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Affiliation(s)
- Tomáš Veverka
- Department of Neurology, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic
| | - Petr Hluštík
- Department of Neurology, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic; Department of Radiology, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic
| | - Pavel Hok
- Department of Neurology, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic
| | - Pavel Otruba
- Department of Neurology, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic
| | - Jana Zapletalová
- Department of Biophysics, Biometry and Statistics, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic
| | - Zbyněk Tüdös
- Department of Radiology, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic
| | - Alois Krobot
- Department of Physiotherapy, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic
| | - Petr Kaňovský
- Department of Neurology, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic
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Furuya S, Hanakawa T. The curse of motor expertise: Use-dependent focal dystonia as a manifestation of maladaptive changes in body representation. Neurosci Res 2015; 104:112-9. [PMID: 26689332 DOI: 10.1016/j.neures.2015.12.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 11/27/2015] [Accepted: 12/01/2015] [Indexed: 01/20/2023]
Abstract
Focal task-specific dystonia (FTSD) impairs not only motor dexterity, but also somatosensory perception involved in well-trained behavioral tasks. Occupations that carry a risk of developing FTSD include musician, writer, painter, surgeon, and golfer, which are characterized by repetitive and precise motor actions over a prolonged period. Behavioral studies have uncovered various undesirable effects of FTSD on sensorimotor functions, such as a loss of independent movement control, unintended muscular co-activation, awkward limb posture, and impairment of fine discrimination of tactile and proprioceptive sensations. Studies using neuroimaging and noninvasive brain stimulation techniques have related such sensorimotor malfunctions to maladaptive neuroplastic changes in the sensorimotor system, including the primary motor and somatosensory areas, premotor area, cerebellum, and basal ganglia. In this review, we summarize recent empirical findings regarding phenomenological and pathophysiological abnormalities associated with the development of FTSD. We particularly focused on maladaptive alterations of body representations underlying the degradation of fine motor control and somatosensory perception in FTSD patients.
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Affiliation(s)
- Shinichi Furuya
- Musical Skill and Injury Center (MuSIC), Sophia University, Japan; Integrative Brain Imaging Center (IBIC), National Center of Neurology and Psychiatry, Japan.
| | - Takashi Hanakawa
- Musical Skill and Injury Center (MuSIC), Sophia University, Japan; Integrative Brain Imaging Center (IBIC), National Center of Neurology and Psychiatry, Japan.
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Richter A, Hamann M, Wissel J, Volk HA. Dystonia and Paroxysmal Dyskinesias: Under-Recognized Movement Disorders in Domestic Animals? A Comparison with Human Dystonia/Paroxysmal Dyskinesias. Front Vet Sci 2015; 2:65. [PMID: 26664992 PMCID: PMC4672229 DOI: 10.3389/fvets.2015.00065] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 11/13/2015] [Indexed: 12/17/2022] Open
Abstract
Dystonia is defined as a neurological syndrome characterized by involuntary sustained or intermittent muscle contractions causing twisting, often repetitive movements, and postures. Paroxysmal dyskinesias are episodic movement disorders encompassing dystonia, chorea, athetosis, and ballism in conscious individuals. Several decades of research have enhanced the understanding of the etiology of human dystonia and dyskinesias that are associated with dystonia, but the pathophysiology remains largely unknown. The spontaneous occurrence of hereditary dystonia and paroxysmal dyskinesia is well documented in rodents used as animal models in basic dystonia research. Several hyperkinetic movement disorders, described in dogs, horses and cattle, show similarities to these human movement disorders. Although dystonia is regarded as the third most common movement disorder in humans, it is often misdiagnosed because of the heterogeneity of etiology and clinical presentation. Since these conditions are poorly known in veterinary practice, their prevalence may be underestimated in veterinary medicine. In order to attract attention to these movement disorders, i.e., dystonia and paroxysmal dyskinesias associated with dystonia, and to enhance interest in translational research, this review gives a brief overview of the current literature regarding dystonia/paroxysmal dyskinesia in humans and summarizes similar hereditary movement disorders reported in domestic animals.
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Affiliation(s)
- Angelika Richter
- Faculty of Veterinary Medicine, Institute of Pharmacology, Pharmacy and Toxicology, University of Leipzig, Leipzig, Germany
| | - Melanie Hamann
- Department of Veterinary Medicine, Institute of Pharmacology and Toxicology, Free University Berlin, Berlin, Germany
| | - Jörg Wissel
- Department of Neurological Rehabilitation and Physical Therapy, Vivantes Hospital Spandau and Humboldt Hospital, Berlin, Germany
- Department of Neurology, Vivantes Hospital Spandau and Humboldt Hospital, Berlin, Germany
| | - Holger A. Volk
- Clinical Science and Services, The Royal Veterinary College, Hatfield, UK
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Galazka M, Soszynski D, Dmitruk K. Central Action of Botulinum Toxin Type A – Is It Possible? NEUROPHYSIOLOGY+ 2015. [DOI: 10.1007/s11062-015-9540-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Pitkänen M, Kallioniemi E, Julkunen P. Extent and Location of the Excitatory and Inhibitory Cortical Hand Representation Maps: A Navigated Transcranial Magnetic Stimulation Study. Brain Topogr 2015; 28:657-665. [PMID: 26133678 DOI: 10.1007/s10548-015-0442-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 06/24/2015] [Indexed: 01/16/2023]
Abstract
Voluntary muscle action and control are modulated by the primary motor cortex, which is characterized by a well-defined somatotopy. Muscle action and control depend on a sensitive balance between excitatory and inhibitory mechanisms in the cortex and in the corticospinal tract. The cortical locations evoking excitatory and inhibitory responses in brain stimulation can be mapped, for example, as a pre-surgical procedure. The purpose of this study was to find the differences between excitatory and inhibitory motor representations mapped using navigated transcranial magnetic stimulation (nTMS). The representations of small hand muscles were mapped to determine the areas and the center of gravities (CoGs) in both hemispheres of healthy right-handed volunteers. The excitatory representations were obtained via resting motor evoked potential (MEP) mapping, with and without a stimulation grid. The inhibitory representations were mapped using the grid and measuring corticospinal silent periods (SPs) during voluntary muscle contraction. The excitatory representations were larger on the dominant hemisphere compared with the non-dominant (p < 0.05). The excitatory CoGs were more medial (p < 0.001) and anterior (p < 0.001) than the inhibitory CoGs. The use of the grid did not influence the areas or the CoGs. The results support the common hypothesis that the MEP and SP representations are located at adjacent sites. Furthermore, the dominant hemisphere seems to be better organized for controlling excitatory motor functions with respect to TMS. In addition, the inhibitory representations could provide further information about motor reorganization and aid in surgery planning when the functional cortical representations are located in abnormal cortical regions.
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Affiliation(s)
- Minna Pitkänen
- Department of Clinical Neurophysiology, Kuopio University Hospital, POB 100, 70029, KYS, Finland. .,Department of Neuroscience and Biomedical Engineering, Aalto University School of Science, POB 12200, 00076, Aalto, Finland.
| | - Elisa Kallioniemi
- Department of Clinical Neurophysiology, Kuopio University Hospital, POB 100, 70029, KYS, Finland.,Department of Applied Physics, University of Eastern Finland, POB 1627, 70211, Kuopio, Finland
| | - Petro Julkunen
- Department of Clinical Neurophysiology, Kuopio University Hospital, POB 100, 70029, KYS, Finland.,Department of Applied Physics, University of Eastern Finland, POB 1627, 70211, Kuopio, Finland
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Current uses of botulinum toxin A as an adjunct to hand therapy interventions of hand conditions. J Hand Ther 2014; 27:85-94; quiz 95. [PMID: 24524884 DOI: 10.1016/j.jht.2013.12.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 12/02/2013] [Accepted: 12/02/2013] [Indexed: 02/03/2023]
Abstract
STUDY DESIGN Literature review. DISCUSSION Botulinum toxin A, a neurotoxin causing temporary muscle paralysis at the neuromuscular junction, has been used to treat multiple acquired conditions of the hand and upper extremity. Initially approved for use in treating blepharospasm and strabismus in the 1980s, indications have expanded to include spasticity associated with cerebrovascular accidents, vasospastic disorders, focal dystonias, and pain conditions. This article reviews the current literature discussing the efficacy of botulinum toxin A in management of disorders of the hand and upper extremity relevant to hand therapists. LEVEL OF EVIDENCE NA.
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Quartarone A, Rizzo V, Terranova C, Milardi D, Bruschetta D, Ghilardi MF, Girlanda P. Sensory abnormalities in focal hand dystonia and non-invasive brain stimulation. Front Hum Neurosci 2014; 8:956. [PMID: 25538594 PMCID: PMC4257013 DOI: 10.3389/fnhum.2014.00956] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 11/10/2014] [Indexed: 11/29/2022] Open
Abstract
It has been proposed that synchronous and convergent afferent input arising from repetitive motor tasks may play an important role in driving the maladaptive cortical plasticity seen in focal hand dystonia (FHD). This hypothesis receives support from several sources. First, it has been reported that in subjects with FHD, paired associative stimulation produces an abnormal increase in corticospinal excitability, which was not confined to stimulated muscles. These findings provide support for the role of excessive plasticity in FHD. Second, the genetic contribution to the dystonias is increasingly recognized indicating that repetitive, stereotyped afferent inputs may lead to late-onset dystonia, such as FHD, more rapidly in genetically susceptible individuals. It can be postulated, according to the two factor hypothesis that dystonia is triggered and maintained by the concurrence of environmental factors such as repetitive training and subtle abnormal mechanisms of plasticity within somatosensory loop. In the present review, we examine the contribution of sensory-motor integration in the pathophysiology of primary dystonia. In addition, we will discuss the role of non-invasive brain stimulation as therapeutic approach in FHD.
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Affiliation(s)
- Angelo Quartarone
- Department of Neurosciences, Psychiatry and Anaesthesiological Sciences, University of Messina , Messina , Italy ; Department of Physiology, Pharmacology and Neuroscience, City University of New York (CUNY) Medical School , New York, NY , USA
| | - Vincenzo Rizzo
- Department of Neurosciences, Psychiatry and Anaesthesiological Sciences, University of Messina , Messina , Italy
| | - Carmen Terranova
- Department of Neurosciences, Psychiatry and Anaesthesiological Sciences, University of Messina , Messina , Italy
| | - Demetrio Milardi
- IRCCS Centro Neurolesi Bonino-Pulejo , Messina , Italy ; Department of Biomedical Science and Morphological and Functional Images, University of Messina , Messina , Italy
| | - Daniele Bruschetta
- Department of Biomedical Science and Morphological and Functional Images, University of Messina , Messina , Italy
| | - Maria Felice Ghilardi
- Department of Physiology, Pharmacology and Neuroscience, City University of New York (CUNY) Medical School , New York, NY , USA
| | - Paolo Girlanda
- Department of Neurosciences, Psychiatry and Anaesthesiological Sciences, University of Messina , Messina , Italy
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Wagle Shukla A, Vaillancourt DE. Treatment and physiology in Parkinson's disease and dystonia: using transcranial magnetic stimulation to uncover the mechanisms of action. Curr Neurol Neurosci Rep 2014; 14:449. [PMID: 24771105 DOI: 10.1007/s11910-014-0449-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Transcranial magnetic stimulation (TMS) has served as an important technological breakthrough in the field of the physiology of movement disorders over the last three decades. TMS has grown popular owing to the ease of application as well as its painless and noninvasive character. The technique has provide important insights into understanding the pathophysiology of movement disorders, particularly Parkinson's disease and dystonia. The basic applications have included the study of motor cortex excitability, functioning of excitatory and inhibitory circuits, study of interactions between sensory and motor systems, and the plasticity response of the brain. TMS has also made important contributions to understanding the response to treatments such as dopaminergic medications, botulinum toxin injections, and deep brain stimulation surgery. This review summarizes the knowledge gained to date with TMS in Parkinson's disease and dystonia, and highlights the current challenges in the use of TMS technology.
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Affiliation(s)
- Aparna Wagle Shukla
- Department of Neurology and Center for Movement Disorders and Neurorestoration, University of Florida, 3450 Hull Road, Gainesville, FL, 32607, USA,
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van de Ruit M, Perenboom MJL, Grey MJ. TMS brain mapping in less than two minutes. Brain Stimul 2014; 8:231-9. [PMID: 25556004 DOI: 10.1016/j.brs.2014.10.020] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 10/23/2014] [Accepted: 10/23/2014] [Indexed: 10/24/2022] Open
Abstract
BACKGROUND Transcranial magnetic stimulation (TMS) corticospinal excitability maps are a valuable tool to study plasticity in the corticospinal tract. Traditionally, data acquisition for a single map is time consuming, limiting the method's applicability when excitability changes quickly, such as during motor learning, and in clinical investigations where assessment time is a limiting factor. OBJECTIVE To reduce the time needed to create a reliable map by 1) investigating the minimum interstimulus interval (ISI) at which stimuli may be delivered, and 2) investigating the minimum number of stimuli required to create a map. METHOD Frameless stereotaxy was used to monitor coil position as the coil was moved pseudorandomly within a 6 × 6 cm square. Maps were acquired using 1-4 s ISIs in 12 participants. The minimum number of stimuli was determined by randomly extracting data and comparing the resulting map to the original data set. To confirm validity, the pseudorandom walk method was compared against a traditional mapping method. RESULTS Reliable maps could be created with 63 stimuli recorded with a 1 s ISI. Maps created acquiring data using the pseudorandom walk method were not significantly different from maps acquired following the traditional method. CONCLUSIONS To account for inter-participant variability, outliers, coil positioning errors and, most importantly, participant comfort during data acquisition, we recommend creating a map with 80 stimuli and a 1.5 s ISI. This makes it possible to acquire TMS maps in 2 min, making mapping a more feasible tool to study short- and long-term changes in cortical organization.
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Affiliation(s)
- Mark van de Ruit
- NIHR Surgical Reconstruction and Microbiology Research Centre, School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Edgbaston B15 2TT, UK; MRC-ARUK Centre for Musculoskeletal Ageing Research, School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Edgbaston B15 2TT, UK
| | - Matthijs J L Perenboom
- Department of Biomechanical Engineering, Delft University of Technology, Delft, the Netherlands
| | - Michael J Grey
- NIHR Surgical Reconstruction and Microbiology Research Centre, School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Edgbaston B15 2TT, UK; MRC-ARUK Centre for Musculoskeletal Ageing Research, School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Edgbaston B15 2TT, UK; Department of Neuroscience and Pharmacology, Panum Institute, University of Copenhagen, Copenhagen, Denmark.
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Veverka T, Hluštík P, Hok P, Otruba P, Tüdös Z, Zapletalová J, Krobot A, Kaňovský P. Cortical activity modulation by botulinum toxin type A in patients with post-stroke arm spasticity: real and imagined hand movement. J Neurol Sci 2014; 346:276-83. [PMID: 25255982 DOI: 10.1016/j.jns.2014.09.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 09/04/2014] [Accepted: 09/08/2014] [Indexed: 10/24/2022]
Abstract
BACKGROUND Our aim was to use functional magnetic resonance imaging (fMRI) to compare brain activation changes due to botulinum toxin A (BoNT) application between two chronic stroke patient groups with different degree of weakness treated for upper limb spasticity. METHODS Fourteen ischemic stroke patients with hand weakness and spasticity were studied. Spasticity was scored by modified Ashworth scale (MAS). FMRI was performed 3 times: before (W0) and 4 (W4) and 11 weeks (W11) after BoNT application. Group A: 7 patients (2 males, 5 females; mean age 59.14 years) with hand plegia, who imagined moving fingers. Group B: 7 age-matched patients (6 males, 1 female; mean age 59.57 years) able to perform sequential finger movement. RESULTS BoNT transiently lowered MAS in W4 in both groups. In group A, activation of the frontal premotor cortex dominated and persisted for all three fMRI sessions whereas the ipsilesional cerebellum and cortex bordering bilateral intraparietal sulcus activation changed over time. Between-session contrasts showed treatment-related activation decreases in the mesial occipitoparietal and lateral occipital cortex. In group B, brain activation was markedly reduced after BoNT (W4). Whereas some of these areas manifested only transient reduction and expanded again at W11, in others the reduction persisted. CONCLUSION Study of two age-matched groups with mild and severe weakness demonstrated different effects of BoNT-lowered spasticity on sensorimotor networks. Group A performing movement imagery manifested BoNT-induced reduction of activation in structures associated with visual imagery. Group B performing movement manifested reduced activation extent and reduced activation of structures outside classical motor system, suggestive of motor network normalization.
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Affiliation(s)
- Tomáš Veverka
- Department of Neurology, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic.
| | - Petr Hluštík
- Department of Neurology, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic; Department of Radiology, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic
| | - Pavel Hok
- Department of Neurology, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic
| | - Pavel Otruba
- Department of Neurology, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic
| | - Zbyněk Tüdös
- Department of Radiology, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic
| | - Jana Zapletalová
- Department of Biophysics, Biometry and Statistics, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic
| | - Alois Krobot
- Department of Physiotherapy, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic
| | - Petr Kaňovský
- Department of Neurology, Faculty of Medicine and Dentistry, Palacký University and University Hospital, Olomouc, Czech Republic
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Methods for estimating cortical motor representation size and location in navigated transcranial magnetic stimulation. J Neurosci Methods 2014; 232:125-33. [DOI: 10.1016/j.jneumeth.2014.05.020] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 05/14/2014] [Accepted: 05/15/2014] [Indexed: 11/20/2022]
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Cerasa A, Nisticò R, Salsone M, Bono F, Salvino D, Morelli M, Arabia G, Quattrone A. Neuroanatomical correlates of dystonic tremor: a cross-sectional study. Parkinsonism Relat Disord 2013; 20:314-7. [PMID: 24405756 DOI: 10.1016/j.parkreldis.2013.12.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 12/02/2013] [Accepted: 12/18/2013] [Indexed: 11/29/2022]
Abstract
PURPOSE This study is aimed at investigating the neuroanatomical patterns characterizing dystonic tremor in comparison with essential tremor. METHODS Voxel-based morphometry and cortical thickness data of 12 patients with dystonic tremor, 14 patients with essential tremor and 23 age- and sex-matched healthy control subjects were analyzed. RESULTS Patients with dystonic tremor showed a thickening and increased gray matter volume (surviving whole-brain correction for multiple comparisons) of the left sensorimotor cortex when compared to other groups. Otherwise, patients with essential tremor were characterized by a subtle atrophy of the anterior cerebellar cortex. DISCUSSION Our multimodal structural neuroimaging study demonstrated that patients with dystonic tremor and essential tremor are characterized by different neuroanatomical abnormalities. The involvement of the sensorimotor cortex in patients with dystonic tremor suggests that this disorder may share some pathophysiological mechanisms with focal dystonia.
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Affiliation(s)
- Antonio Cerasa
- Neuroimaging Research Unit, Institute of Bioimaging and Molecular Physiology, National Research Council, Germaneto, Catanzaro, Italy
| | - Rita Nisticò
- Neuroimaging Research Unit, Institute of Bioimaging and Molecular Physiology, National Research Council, Germaneto, Catanzaro, Italy
| | - Maria Salsone
- Institute of Neurology, University "Magna Graecia", Germaneto, Catanzaro, Italy
| | - Francesco Bono
- Institute of Neurology, University "Magna Graecia", Germaneto, Catanzaro, Italy
| | - Dania Salvino
- Institute of Neurology, University "Magna Graecia", Germaneto, Catanzaro, Italy
| | - Maurizio Morelli
- Institute of Neurology, University "Magna Graecia", Germaneto, Catanzaro, Italy
| | - Gennarina Arabia
- Institute of Neurology, University "Magna Graecia", Germaneto, Catanzaro, Italy
| | - Aldo Quattrone
- Neuroimaging Research Unit, Institute of Bioimaging and Molecular Physiology, National Research Council, Germaneto, Catanzaro, Italy; Institute of Neurology, University "Magna Graecia", Germaneto, Catanzaro, Italy.
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Altered striatal and pallidal connectivity in cervical dystonia. Brain Struct Funct 2013; 220:513-23. [PMID: 24259114 DOI: 10.1007/s00429-013-0671-y] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2013] [Accepted: 10/31/2013] [Indexed: 12/30/2022]
Abstract
Cervical dystonia is a neurological movement disorder characterized by involuntary, abnormal movements of the head and neck. Injecting the overactive muscles with botulinum toxin is the gold standard treatment, supported by good evidence (Delnooz and van de Warrenburg in Ther Adv Neurol Disord 5:221-240, 2012). Current views on its pathophysiology support a role for the basal ganglia, although there are probably more widespread abnormalities in brain networks in which the basal ganglia are important nodes. Their precise role in cervical dystonia is unknown. We sought to address this issue by examining alterations in the functional connectivity of the basal ganglia. Using resting-state functional MRI and functional parcellations, we investigated functional connectivity in cervical dystonia patients and age- and gender-matched healthy controls. We mapped connectivity voxel-wise across the striatum and the globus pallidus for a set of brain masks, defined from well-known resting-state networks. Scans were repeated before and after botulinum toxin injections to see whether connectivity abnormalities were perhaps restored. We found that in cervical dystonia (1) the right mid-dorsal putamen and right external globus pallidus have reduced connectivity with a network comprising left fronto-parietal regions; and (2) the bilateral anterior putamen shows a trend towards enhanced connectivity with a network comprising sensorimotor areas. We observed that botulinum toxin treatment induces reorganization between a network comprising mainly (pre)frontal areas and (1) the right mid-ventral striatum and (2) the right external globus pallidus. Cervical dystonia patients have altered functional connectivity between the basal ganglia and some cortical regions that are part of specific brain networks that in part are influenced by botulinum toxin treatment. These connectivity abnormalities may be primary as well as secondary, perhaps compensatory, phenomena.
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Wang M, Li ZY, Xu WD, Hua XY, Xu JG, Gu YD. Sensory restoration in cortical level after a contralateral C7 nerve transfer to an injured arm in rats. Neurosurgery 2013; 67:136-43; discussion 143. [PMID: 20559101 DOI: 10.1227/01.neu.0000370603.45342.6b] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND The restoration of sensory and motor function in brachial plexus root avulsion patients is a difficult challenge. The central nervous system plays an important role in sensory recovery after peripheral nerve injury and repair. OBJECTIVE To investigate the sensory restoration process after surgery at the cortical level in rodent models with a contralateral C7 nerve transfer. METHODS Thirty-five male Sprague-Dawley rats were used in this experiment, and both behavioral tests and somatosensory evoked potentials were used to investigate the sensory function recovery of the injured forepaws and the cortical reorganization in the rats postoperatively. RESULTS The results demonstrated a dynamic change in the ipsilateral somatosensory cortex, both in the shape and location, where overlapping sensory cortical representations of the healthy and injured forepaws were observed consistently. Behavioral tests show that the sensation first occurred only in the healthy forepaw and later in both when stimulating the injured one, which suggested a tendency of the sensation function to recover in the injured forepaws of the rats as time progressed. CONCLUSION The cortical reorganization occurred only in the ipsilateral hemisphere, which is different from the motor cortex reorganization using the same model as that described in a previous study. This reorganization pattern offers an interpretation of the unique sensory recovery process after the transfer of the C7 nerve to the contralateral median nerve, but also provides the basis for further sensory restoration in clinical practice.
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Affiliation(s)
- Meng Wang
- Department of Hand Surgery, Huashan Hospital, Shanghai Medical College of Fudan University, Shanghai, People's Republic of China
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Delnooz CCS, Pasman JW, Beckmann CF, van de Warrenburg BPC. Task-free functional MRI in cervical dystonia reveals multi-network changes that partially normalize with botulinum toxin. PLoS One 2013; 8:e62877. [PMID: 23650536 PMCID: PMC3641096 DOI: 10.1371/journal.pone.0062877] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2012] [Accepted: 03/27/2013] [Indexed: 11/18/2022] Open
Abstract
Cervical dystonia is characterized by involuntary, abnormal movements and postures of the head and neck. Current views on its pathophysiology, such as faulty sensorimotor integration and impaired motor planning, are largely based on studies of focal hand dystonia. Using resting state fMRI, we explored whether cervical dystonia patients have altered functional brain connectivity compared to healthy controls, by investigating 10 resting state networks. Scans were repeated immediately before and some weeks after botulinum toxin injections to see whether connectivity abnormalities were restored. We here show that cervical dystonia patients have reduced connectivity in selected regions of the prefrontal cortex, premotor cortex and superior parietal lobule within a distributed network that comprises the premotor cortex, supplementary motor area, primary sensorimotor cortex, and secondary somatosensory cortex (sensorimotor network). With regard to a network originating from the occipital cortex (primary visual network), selected regions in the prefrontal and premotor cortex, superior parietal lobule, and middle temporal gyrus areas have reduced connectivity. In selected regions of the prefrontal, premotor, primary motor and early visual cortex increased connectivity was found within a network that comprises the prefrontal cortex including the anterior cingulate cortex and parietal cortex (executive control network). Botulinum toxin treatment resulted in a partial restoration of connectivity abnormalities in the sensorimotor and primary visual network. These findings demonstrate the involvement of multiple neural networks in cervical dystonia. The reduced connectivity within the sensorimotor and primary visual networks may provide the neural substrate to expect defective motor planning and disturbed spatial cognition. Increased connectivity within the executive control network suggests excessive attentional control and while this may be a primary trait, perhaps contributing to abnormal motor control, this may alternatively serve a compensatory function in order to reduce the consequences of the motor planning defect inflicted by the other network abnormalities.
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Affiliation(s)
- Cathérine C S Delnooz
- Radboud University Medical Centre, Donders Institute for Brain, Cognition and Behaviour, Department of Neurology, Nijmegen, The Netherlands
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Botulinum toxin modulates cortical maladaptation in post-stroke spasticity. Muscle Nerve 2013; 48:93-9. [DOI: 10.1002/mus.23719] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/06/2012] [Indexed: 12/25/2022]
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The BDNF val(66)met polymorphism is not related to motor function or short-term cortical plasticity in elderly subjects. Brain Res 2012; 1495:1-10. [PMID: 23247064 DOI: 10.1016/j.brainres.2012.12.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 12/03/2012] [Accepted: 12/04/2012] [Indexed: 11/22/2022]
Abstract
The brain derived neurotrophic factor (BDNF) val(66)met polymorphism affects function of the motor system in young subjects, but little is known about motor system effects in the elderly. The current study assessed motor system physiology and behavior, plus a measure of short-term motor cortex plasticity using transcranial magnetic stimulation, in 38 elderly subjects, then examined whether findings varied in relation to BDNF genotype. Baseline data were also collected from 14 young subjects. At baseline, elderly subjects had poorer motor performances, larger motor cortex maps, and smaller motor evoked potentials compared to young subjects. Degree of age-related differences in neurophysiology correlated inversely with motor performance, for example, larger map area correlated with weaker pinch grip force (r=-0.42, P=0.01). In elderly subjects, baseline behavior and neurophysiology did not differ in relation to BDNF genotype. In addition, although map area increased significantly (P=0.03) across 30 min of exercise, this change did not vary according to BDNF genotype. Aging is associated with changes in neurophysiology that might represent a compensatory response. The data do not support an association between BDNF genotype and behavior, neurophysiology, or short-term cortical plasticity in the motor system of healthy elderly subjects.
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Karp BI. Botulinum toxin physiology in focal hand and cranial dystonia. Toxins (Basel) 2012; 4:1404-14. [PMID: 23202323 PMCID: PMC3509715 DOI: 10.3390/toxins4111404] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Revised: 10/24/2012] [Accepted: 11/09/2012] [Indexed: 11/16/2022] Open
Abstract
The safety and efficacy of botulinum toxin for the treatment of focal hand and cranial dystonias are well-established. Studies of these adult-onset focal dystonias reveal both shared features, such as the dystonic phenotype of muscle hyperactivity and overflow muscle contraction and divergent features, such as task specificity in focal hand dystonia which is not a common feature of cranial dystonia. The physiologic effects of botulinum toxin in these 2 disorders also show both similarities and differences. This paper compares and contrasts the physiology of focal hand and cranial dystonias and of botulinum toxin in the management of these disorders.
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Affiliation(s)
- Barbara Illowsky Karp
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892, USA.
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Thomas AM, Simpson DM. Contralateral weakness following botulinum toxin for poststroke spasticity. Muscle Nerve 2012; 46:443-8. [PMID: 22907238 DOI: 10.1002/mus.23492] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
INTRODUCTION We describe 2 patients who received botulinum toxin A (BoNT) for poststroke spasticity and developed contralateral limb weakness. METHODS Both patients received high doses of BoNT with large dilution volumes and injection in the proximal upper extremity muscles, and developed weakness of the contralateral upper limb. These patients then underwent electrodiagnostic testing of the affected limb. RESULTS Repetitive nerve stimulation of the axillary and spinal accessory nerves revealed decrements of 23% and 16%, respectively. EMG revealed abnormal spontaneous activity and small polyphasic motor unit potentials with reduced recruitment. These findings indicated blockade of the neuromuscular junction. Both patients improved. CONCLUSIONS Isolated weakness of the contralateral limb after BoNT injection for poststroke spasticity suggests diffusion of toxin through tissue planes from proximal upper extremity muscles, across the midline, to contralateral muscles. High doses of botulinum toxin, high dilution volumes, and injection of proximal upper extremity muscles appear to be risk factors for this adverse effect.
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Affiliation(s)
- Anila M Thomas
- Clinical Neurophysiology Laboratory, Department of Neurology, Mount Sinai Medical Center, One Gustave Levy Place, Box 1052, New York, New York 10029, USA
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Filipović SR. Dystonia--a disorder of dynamics of brain plasticity modulation? Acta Physiol (Oxf) 2012; 206:160-3. [PMID: 23017103 DOI: 10.1111/apha.12002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- S. R. Filipović
- Department of Neurophysiology Institute for Medical Research; University of Belgrade; Belgrade; Serbia
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Tyč F, Boyadjian A, Allam N, Brasil-Neto JP. Abnormal acute changes in upper limb muscle cortical representation areas in the patients with writer's cramp during co-activation of distal and proximal muscles. Acta Physiol (Oxf) 2012; 206:195-207. [PMID: 22574750 DOI: 10.1111/j.1748-1716.2012.02451.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 01/22/2012] [Accepted: 05/03/2012] [Indexed: 11/27/2022]
Abstract
AIM We analysed cortical muscle representation areas during single muscle activation and during the co-activation of several upper arm muscles in the patients with writer's cramp to determine the possible occurrence of abnormal dynamic somatotopic changes in M1, in addition to the static map abnormalities already described in this form of dystonia. METHODS Using transcranial magnetic stimulation, we assessed cortical representations of medial deltoid, extensor carpi radialis and the first dorsal interosseus muscles in eight patients with writer's cramp and in eight healthy control subjects. Cortical maps were obtained during distal muscles' activation either in isolation or in conjunction with voluntary medial deltoid co-activation. RESULTS This study showed a difference in the organization of cortical representations of these muscles between the patients with dystonia and control subjects. The first dorsal interosseus and the extensor carpi radialis cortical representation areas were larger in the dystonic group. The cortical representations became larger when the medial deltoid was simultaneously co-activated, and this effect was not observed in the control group. In the dystonic group, the three cortical muscle representations largely overlapped and their centres of gravity were closer. CONCLUSION Patients with dystonia showed not only a different spatial organization of muscle cortical representation areas, but also abnormal acute somatotopic changes during proximal muscle co-activation. Task-specific motor impairment in writer's cramp may result not only from lack of cortical inhibition and the well-known anomalous cortical organization observed in these patients, but also from abnormal patterns of proximo-distal functional muscle coupling.
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Affiliation(s)
| | | | | | - J. P. Brasil-Neto
- Laboratório de Neurociências e Comportamento; Universidade de Brasilia (UnB); Distrito Federal; Brasil
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Fabregat G, Asensio-Samper JM, Palmisani S, Villanueva-Pérez VL, De Andrés J. Subcutaneous botulinum toxin for chronic post-thoracotomy pain. Pain Pract 2012; 13:231-4. [PMID: 22716282 DOI: 10.1111/j.1533-2500.2012.00569.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Botulinum toxin is a neurotoxin that has been widely used in chronic pain for the treatment of multiple conditions with a component of localized muscle spasm. Recent studies suggest that botulinum toxin is effective in the treatment of neuropathic pain syndromes such as post-herpetic neuralgia. CASE REPORT We report the case of a 67-year-old man who underwent atypical segmentectomy of a right lower lobe lung nodule. The patient was referred to our pain management department with a of 2-year history persistent pain along the thoracotomy scar having a predominantly neuropathic component, refractory to standard treatments. He was successfully treated with subcutaneous botulinum toxin type A. DISCUSSION On the basics of our own experience and on the analysis of the reports published in the literature, fractioned subcutaneous injections of botulinum toxin may be useful for the treatment of various chronic localized pain conditions including chronic post-thoracotomy pain.
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Affiliation(s)
- Gustavo Fabregat
- Department of Multidisciplinary Pain Management, General University Hospital, Valencia, Spain.
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Colosimo C, Tiple D, Berardelli A. Efficacy and Safety of Long-term Botulinum Toxin Treatment in Craniocervical Dystonia: A Systematic Review. Neurotox Res 2012; 22:265-73. [DOI: 10.1007/s12640-012-9314-y] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Revised: 01/09/2012] [Accepted: 01/31/2012] [Indexed: 11/25/2022]
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Castrop F, Dresel C, Hennenlotter A, Zimmer C, Haslinger B. Basal ganglia-premotor dysfunction during movement imagination in writer's cramp. Mov Disord 2012; 27:1432-9. [PMID: 22328061 DOI: 10.1002/mds.24944] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2011] [Revised: 12/05/2011] [Accepted: 01/12/2012] [Indexed: 11/06/2022] Open
Abstract
The pathophysiology of idiopathic focal hand dystonia (writer's cramp) is characterized by deficient inhibitory basal ganglia function and altered cortical sensorimotor processing. To explore if this is already a primary finding in dystonia for internal movement simulation independent of dystonic motor output or abnormal sensory input, we investigated the neural correlates of movement imagination and observation in patients with writer's cramp. Event-related fMRI was applied during kinesthetic motor imagery of drawing simple geometric figures (imagination task) and passively observing videos of hands drawing identical figures (observation task). Compared with healthy controls, patients with writer's cramp showed deficient activation of the left primary sensorimotor cortex, mesial and left dorsal premotor cortex, bilateral putamen, and bilateral thalamus during motor imagery. No significant signal differences between both groups were found during the observation task. We conclude that internal movement simulation and planning as tested during imagination of hand movements appear to be dysfunctional in patients with writer's cramp, whereas visual signal processing and observation-induced activation are unaffected. Deficient basal ganglia-premotor activation could be a correlate of impaired basal ganglia inhibition and focusing during the selection of motor programs in dystonia. This finding seems to be an intrinsic deficit, as it is found during motor imagery in the absence of dystonic symptoms.
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Affiliation(s)
- Florian Castrop
- Department of Neurology, Klinikum rechts der Isar, Technische Universität München, Germany
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