Posts Tagged repetitive transcranial magnetic stimulation

[ARTICLE] Interindividual differences in motor network connectivity and behavioral response to iTBS in stroke patients – Full Text

Highlights

Multimodal assessment of motor system integrity for predicting iTBS-aftereffects

Effective connectivity of M1 predicts behavioral iTBS-aftereffects

No association between iTBS-aftereffects and BOLD activity or RMT/AMT/SICI

Effects of brain stimulation strongly influenced by connectivity of stimulated region

Abstract

Cerebral plasticity-inducing approaches like repetitive transcranial magnetic stimulation (rTMS) are of high interest in situations where reorganization of neural networks can be observed, e.g., after stroke. However, an increasing number of studies suggest that improvements in motor performance of the stroke-affected hand following modulation of primary motor cortex (M1) excitability by rTMS shows a high interindividual variability. We here tested the hypothesis that in stroke patients the interindividual variability of behavioral response to excitatory rTMS is related to interindividual differences in network connectivity of the stimulated region. Chronic stroke patients (n = 14) and healthy controls (n = 12) were scanned with functional magnetic resonance imaging (fMRI) while performing a simple hand motor task. Dynamic causal modeling (DCM) was used to investigate effective connectivity of key motor regions. On two different days after the fMRI experiment, patients received either intermittent theta-burst stimulation (iTBS) over ipsilesional M1 or control stimulation over the parieto-occipital cortex. Motor performance and TMS parameters of cortical excitability were measured before and after iTBS. Our results revealed that patients with better motor performance of the affected hand showed stronger endogenous coupling from supplemental motor area (SMA) onto M1 before starting the iTBS intervention. Applying iTBS to ipsilesional M1 significantly increased ipsilesional M1 excitability and decreased contralesional M1 excitability as compared to control stimulation. Individual behavioral improvements following iTBS specifically correlated with neural coupling strengths in the stimulated hemisphere prior to stimulation, especially for connections targeting the stimulated M1. Combining endogenous connectivity and behavioral parameters explained 82% of the variance in hand motor performance observed after iTBS. In conclusion, the data suggest that the individual susceptibility to iTBS after stroke is influenced by interindividual differences in motor network connectivity of the lesioned hemisphere.

1. Introduction

Recovery of function after stroke is driven by reorganization of neural networks in both the lesioned and unaffected hemispheres (Cramer, 2008). However, spontaneous recovery after stroke often remains incomplete (Kolominsky-Rabas et al., 2006). One strategy to improve the functional outcome of patients suffering from brain lesions is to modulate cerebral plasticity by means of non-invasive brain stimulation such as, e.g., repetitive transcranial magnetic stimulation (rTMS) (Ridding and Rothwell, 2007). Although to date a direct proof is missing, increasing evidence exist that rTMS-effects are mediated by changes in synaptic transmission (Funke and Benali, 2011 ;  Hoogendam et al., 2010). One specific strategy to ameliorate motor impairments in stroke patients is to enhance cortical excitability of the motor cortex in the lesioned hemisphere (Khedr et al., 2005). An effective protocol of rTMS to induce such increase in excitability of the motor cortex following a relatively short (i.e., 3.5 min) stimulation period is intermittent theta-burst stimulation (iTBS) (Huang et al., 2005).

Consequently, proof-of-principle studies have been able to demonstrate that iTBS applied to ipsilesional M1 improve hand motor function in stroke patients (Ackerley et al., 2010Hsu et al., 2012 ;  Talelli et al., 2007b). A major issue, however, with rTMS (including iTBS) induced cerebral plasticity is high inter-individual variability of the effects induced in both healthy subjects (Daskalakis et al., 2006Hamada et al., 2013 ;  Muller-Dahlhaus et al., 2008) and stroke patients (Ameli et al., 2009 ;  Grefkes and Fink, 2012). For example, Hamada et al. (2013) demonstrated that application of iTBS in healthy subjects leads to an increase of motor-cortical excitability in only 52% subjects, while the other half responded in an opposite way with a decrease of excitability. Likewise, Ameli et al. (2009) reported that in patients suffering from cortical strokes, only half of them showed behavioral improvements after 10 Hz rTMS while the other half even deteriorated with their stroke affected hands. Such opposed stimulation after-effects are likely to contribute to absent overall effects across the entire group (Hamada et al., 2013).

Apart from known sources of response variability following iTBS like age (Freitas et al., 2011), genetic polymorphisms of the brain-derived neurotrophic factor (Cheeran et al., 2008 ;  Kleim et al., 2006) and technical aspects such as the direction of current flow, the intensity of stimulation and the number of pulses applied (Gamboa et al., 2010Gentner et al., 2008 ;  Talelli et al., 2007a), clinical factors like lesion location, degree of neurological impairment and time since stroke are also likely to impact on the response to rTMS (Grefkes and Fink, 2012). For example, several studies demonstrated that patients with subcortical lesions have a higher probability to improve after rTMS than patients with cortical lesions (Ameli et al., 2009 ;  Hsu et al., 2012). Moreover, the pathomechanisms underlying stroke-induced motor deficits do not only depend on direct tissue damage due to ischemia, but might also comprise network disturbances remote from the stroke lesion (Grefkes and Fink, 2011 ;  Grefkes and Fink, 2014). Thus, changes in network interactions are likely to constitute another important factor for the evolution of rTMS-aftereffects as TMS does not only interfere with neural tissue of the stimulated hemisphere but also with neural activity levels of regions that are interconnected with the stimulation site (Bestmann et al., 2005).

Hence, there is good reason to assume that specific inter-individual differences (or abnormalities post-stroke) in network connectivity might – at least in part – influence response to rTMS. Support for this hypothesis stems from studies with patients suffering from dystonia in which reduced functional connectivity between premotor cortex and M1 was indicative for responding to rTMS (Huang et al., 2010 ;  Quartarone et al., 2003). Furthermore, changes in motor-evoked potential (MEP) amplitudes following rTMS have been shown to be associated with higher effective connectivity between supplementary motor area (SMA), ventral premotor cortex (vPMC) and M1 of the stimulated hemisphere (Cardenas-Morales et al., 2014).

Therefore, in stroke patients, the variability of the individual response to plasticity-inducing intervention might depend on how the stimulation interacts with the pre-existing connectivity in a given functional network, e.g., the motor system. In order to identify factors that are associated with a positive behavioral effect in response to intermittent theta burst stimulation (here: iTBS) applied to ipsilesional M1, we used a multimodal approach consisting of clinical scales, electrophysiological parameters measured using single- and paired-pulse TMS, as well as functional magnetic resonance imaging (fMRI) and dynamic causal modeling (DCM) to assess effective connectivity of the cortical motor network. We reasoned that the systems level perspective offered by DCM might be useful for identifying predictors that indicate whether or not a patient will respond to non-invasive brain stimulation given that (i) focal brain stimulation also impacts on activity levels of areas connected to the stimulation site (Bestmann et al., 2003 ;  Grefkes et al., 2010) and (ii) recovery of motor function depends on changes in the entire motor network rather than changes in M1 only (Rehme et al., 2012 ;  Ward et al., 2003). Here, especially the coupling strengths between ipsilesional M1 and premotor areas might be indicative for the behavioral after-effect of iTBS given the role of these connections in motor performance in both healthy subjects and stroke (Pool et al., 2013Pool et al., 2014 ;  Rehme et al., 2011a). […]

Continue —>  Interindividual differences in motor network connectivity and behavioral response to iTBS in stroke patients

Fig. 4

Fig. 4. Neural activity when patients and controls moved the affected or unaffected hand. Fist closures were conducted at a fixed movement frequency of 0.8 Hz and at a frequency adjusted to individual performance levels. Compared to controls, patients featured enhanced activity in both hemispheres during movements of the affected hand. Movements of the unaffected hand yielded a similar activation pattern in patients and controls. T-values are represented by the color bar. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)

 

 

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[Abstract] Low-frequency rTMS of the unaffected hemisphere in stroke patients: A systematic review

Abstract

The aim of this review was to summarize the evidence for the effectiveness of low-frequency (LF) repetitive transcranial magnetic stimulation (rTMS) over the unaffected hemisphere in promoting functional recovery after stroke. We performed a systematic search of the studies using LF-rTMS over the contralesional hemisphere in stroke patients and reviewed the 67 identified articles. The studies have been gathered together according to the time interval that had elapsed between the stroke onset and the beginning of the rTMS treatment. Inhibitory rTMS of the contralesional hemisphere can induce beneficial effects on stroke patients with motor impairment, spasticity, aphasia, hemispatial neglect and dysphagia, but the therapeutic clinical significance is unclear. We observed considerable heterogeneity across studies in the stimulation protocols. The use of different patient populations, regardless of lesion site and stroke aetiology, different stimulation parameters and outcome measures means that the studies are not readily comparable, and estimating real effectiveness or reproducibility is very difficult. It seems that careful experimental design is needed and it should consider patient selection aspects, rTMS parameters and clinical assessment tools. Consecutive sessions of rTMS, as well as the combination with conventional rehabilitation therapy, may increase the magnitude and duration of the beneficial effects. In an increasing number of studies, the patients have been enrolled early after stroke. The prolonged follow-up in these patients suggests that the effects of contralesional LF-rTMS can be long-lasting. However, physiological evidence indicating increased synaptic plasticity, and thus, a more favourable outcome, in the early enrolled patients, is still lacking. Carefully designed clinical trials designed are required to address this question. LF rTMS over unaffected hemisphere may have therapeutic utility, but the evidence is still preliminary and the findings need to be confirmed in further randomized controlled trials.

Source: Low-frequency rTMS of the unaffected hemisphere in stroke patients: A systematic review – Sebastianelli – 2017 – Acta Neurologica Scandinavica – Wiley Online Library

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[ARTICLE] The Effects of Navigated Repetitive Transcranial Magnetic Simulation and Brunnstrom Movement Therapy on Upper Extremity Proprioceptive Sense and Spasticity in Stroke Patients: A Double-Blind Randomized Trial – Full Text PDF

Abstract

Purpose: The purpose of this study is to investigate the effects of various treatments (repetitive transcranial magnetic stimulation and Brunnstrom movement therapy) on upper extremity proprioceptive sense and spasticity.

Methods: Twenty-one stroke patients were included in the study. The treatment group (Group 1; n=10) was administered navigated real repetitive transcranial magnetic stimulation (rTMS), and the control group (Group 2; n=11) was administered sham rTMS by the first researcher. The patients in both groups had upper extremity exercises according to Brunnstrom movement therapy (BMT). The patients were assessed using the Brunnstrom recovery stages (BRS), proprioceptive sense assessment, and the modified Ashworth scale (MAS).

Results: Between the treatment group and control group patients, there were no significant statistical differences obtained from pre-treatment and postreatment tenth day, first month, and third month by BRS wrist, hand, and upper extremity stages. The intragroup comparison of the treatment group patients revealed a statistically significant difference between the pre-treatment and post-treatment third month BRS-hand and BRS-upper extremity stages.The pretreatment and postreatment tenth day and first month evaluations of the wrist proprioceptive sense of the groups presented a significant difference. There was no statistically significant difference between the groups in terms of MAS scores before and after treatment evaluations.

Conclusion: The rTMS and BMT approaches that were implemented in the study affected the proprioceptive sense of the wrist after the treatment and in the early period but did not change spasticity.

Keywords: Repetitive transcranial magnetic stimulation, stroke, Brunnstrom recovery stages, proprioceptive sense, spasticity

INTRODUCTION

Proprioceptive sense is the individual’s ability to perceive the position and the motion of his/her body segments in the space via somatosensorial impulses sent by the receptors in the skin, muscles, and joints (1). Researchers have stated that the proprioceptive sense, which is the awareness sense of the body, consists of three fundamental senses: kinesthesia, joint position sense, and neuromuscular control (2). The proprioceptive sense plays a crucial role in carrying out and controlling daily activities, maintaining posture and balance, joint stability, and motor learning (3, 4). Neuromuscular control is affected by proprioceptive inefficiencies apart from motor dysfunctions. It has been shown that proprioceptive knowledge is of extreme importance for the neural control of motion and that the upper extremity proprioceptive sense is commonly decreased or evanished following stroke (5). It has been explained that the proprioceptive deficit incidence rate is 50-65% in stroke patients, which affects daily activities and quality of life negatively (6, 7). It has been stated that proprioceptive and motor deficits have different recovery rates in the first six months following stroke (8). In stroke patients, sensorimotor learning calls for a sound somatosensorial impulse, which is possible through sensorimotor rehabilitation (9). The Bobath, Brunnstrom, Johnstone, and Rood proprioceptive neuromuscular facilitation techniques and the motor learning method, commonly utilized by physiotherapists, are based upon treating sensorimotor functions (10). There exist several recent studies that report that the pain-free, non-invasive transcranial magnetic stimulation (rTMS) application decreases spasticity or that it has no effect (11-13). Stroke rehabilitation is provided by decreasing the transcallosal inhibition from the unaffected motor cortex to the affected motor cortex via 1 Hz rTMS applied on the motor cortex (14, 15). Whereas there is a limited number of studies in the literature with various results on the effects of rTMS and physiotherapy combination on spasticity, a study dealing with the effect of rTMS and physiotherapy combination on proprioceptive sense has not been found. This study was planned to investigate the effect of rTMS and Brunnstrom movement therapy (BMT) on upper extremity proprioceptive sense and spasticity (11, 12).

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[Abstract] Breakthroughs in the spasticity management: Are non-pharmacological treatments the future?

Highlights

  • Spasticity can cause a severe disability and challenge the rehabilitation process.
  • A successful treatment of spasticity depends on a pathophysiologic assessment.
  • The main therapeutic options include physiotherapy and pharmacological treatments.
  • Non-pharmacologic approaches may reduce spasticity and improve quality of life.

Abstract

The present paper aims at providing an objective narrative review of the existing non-pharmacological treatments for spasticity. Whereas pharmacologic and conventional physiotherapy approaches result well effective in managing spasticity due to stroke, multiple sclerosis, traumatic brain injury, cerebral palsy and incomplete spinal cord injury, the real usefulness of the non-pharmacological ones is still debated. We performed a narrative literature review of the contribution of non-pharmacological treatments to spasticity management, focusing on the role of non-invasive neurostimulation protocols (NINM). Spasticity therapeutic options available to the physicians include various pharmacological and non-pharmacological approaches (including NINM and vibration therapy), aimed at achieving functional goals for patients and their caregivers. A successful treatment of spasticity depends on a clear comprehension of the underlying pathophysiology, the natural history, and the impact on patient’s performances. Even though further studies aimed at validating non-pharmacological treatments for spasticity should be fostered, there is growing evidence supporting the usefulness of non-pharmacologic approaches in significantly helping conventional treatments (physiotherapy and drugs) to reduce spasticity and improving patient’s quality of life. Hence, non-pharmacological treatments should be considered as a crucial part of an effective management of spasticity.

Source: Breakthroughs in the spasticity management: Are non-pharmacological treatments the future? – Journal of Clinical Neuroscience

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[Abstract] Breakthroughs in the spasticity management: Are non-pharmacological treatments the future?

 

Highlights

    Spasticity can cause a severe disability and challenge the rehabilitation process.
    A successful treatment of spasticity depends on a pathophysiologic assessment.
    The main therapeutic options include physiotherapy and pharmacological treatments.
    Non-pharmacologic approaches may reduce spasticity and improve quality of life.

Abstract

The present paper aims at providing an objective narrative review of the existing non-pharmacological treatments for spasticity. Whereas pharmacologic and conventional physiotherapy approaches result well effective in managing spasticity due to stroke, multiple sclerosis, traumatic brain injury, cerebral palsy and incomplete spinal cord injury, the real usefulness of the non-pharmacological ones is still debated.

We performed a narrative literature review of the contribution of non-pharmacological treatments to spasticity management, focusing on the role of non-invasive neurostimulation protocols (NINM). Spasticity therapeutic options available to the physicians include various pharmacological and non-pharmacological approaches (including NINM and vibration therapy), aimed at achieving functional goals for patients and their caregivers. A successful treatment of spasticity depends on a clear comprehension of the underlying pathophysiology, the natural history, and the impact on patient’s performances.

Even though further studies aimed at validating non-pharmacological treatments for spasticity should be fostered, there is growing evidence supporting the usefulness of non-pharmacologic approaches in significantly helping conventional treatments (physiotherapy and drugs) to reduce spasticity and improving patient’s quality of life.

Hence, non-pharmacological treatments should be considered as a crucial part of an effective management of spasticity.

Source: Breakthroughs in the spasticity management: Are non-pharmacological treatments the future?

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[ARTICLE] Short- and Long-term Effects of Repetitive Transcranial Magnetic Stimulation on Upper Limb Motor Function after Stroke: a Systematic Review and Meta-Analysis – Full Text

The aim of this study was to evaluate the short- and long-term effects as well as other parameters of repetitive transcranial magnetic stimulation (rTMS) on upper limb motor functional recovery after stroke.

The databases of PubMed, Medline, Science Direct, Cochrane, and Embase were searched for randomized controlled studies reporting effects of rTMS on upper limb motor recovery published before October 30, 2016.

The short- and long-term mean effect sizes as well as the effect size of rTMS frequency of pulse, post-stroke onset, and theta burst stimulation patterns were summarized by calculating the standardized mean difference (SMD) and the 95% confidence interval using fixed/random effect models as appropriate.

Thirty-four studies with 904 participants were included in this systematic review. Pooled estimates show that rTMS significantly improved short-term (SMD, 0.43; P < 0.001) and long-term (SMD, 0.49; P < 0.001) manual dexterity. More pronounced effects were found for rTMS administered in the acute phase of stroke (SMD, 0.69), subcortical stroke (SMD, 0.66), 5-session rTMS treatment (SMD, 0.67) and intermittent theta burst stimulation (SMD, 0.60). Only three studies reported mild adverse events such as headache and increased anxiety .

Five-session rTMS treatment could best improve stroke-induced upper limb dyskinesia acutely and in a long-lasting manner. Intermittent theta burst stimulation is more beneficial than continuous theta burst stimulation. rTMS applied in the acute phase of stroke is more effective than rTMS applied in the chronic phase. Subcortical lesion benefit more from rTMS than other lesion site.

Continue —> Short- and Long-term Effects of Repetitive Transcranial Magnetic Stimulation on Upper Limb Motor Function after Stroke: a Systematic Review and Meta-Analysis – Feb 17, 2017

figure

Figure 1. The flow diagram of the selection process.

 

 

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[ARTICLE] Does a combined intervention program of repetitive transcranial magnetic stimulation and intensive occupational therapy affect cognitive function in patients with post-stroke upper limb hemiparesis? – Full Text HTML

 

Abstract

Low-frequency repetitive transcranial magnetic stimulation (LF-rTMS) to the contralesional hemisphere and intensive occupational therapy (iOT) have been shown to contribute to a significant improvement in upper limb hemiparesis in patients with chronic stroke. However, the effect of the combined intervention program of LF-rTMS and iOT on cognitive function is unknown. We retrospectively investigated whether the combined treatment influence patient’s Trail-Making Test part B (TMT-B) performance, which is a group of easy and inexpensive neuropsychological tests that evaluate several cognitive functions. Twenty-five patients received 11 sessions of LF-rTMS to the contralesional hemisphere and 2 sessions of iOT per day over 15 successive days. Patients with right- and left-sided hemiparesis demonstrated significant improvements in upper limb motor function following the combined intervention program. Only patients with right-sided hemiparesis exhibited improved TMT-B performance following the combined intervention program, and there was a significant negative correlation between Fugl-Meyer Assessment scale total score change and TMT-B performance. The results indicate the possibility that LF-rTMS to the contralesional hemisphere combined with iOT improves the upper limb motor function and cognitive function of patients with right-sided hemiparesis. However, further studies are necessary to elucidate the mechanism of improved cognitive function.

 

Introduction
Upper limb hemiparesis is reported to be observed in 55–75% of post-stroke patients, and affects the patient’s activities of daily living and quality of life (Nichols-Larsen et al., 2005; Wolf et al., 2006). Duncan et al. (1992) reported that dramatic recovery of motor function was completed by 1month post-stroke, and that recovery often plateaued by 6 months. In recent years, repetitive transcranial magnetic stimulation (rTMS) has attracted attention as a treatment technique for the sequelae of stroke. It is a non-invasive, painless method to stimulate regions of the cerebral cortex, in which a figure-8 or a round coil converts electrical current into a rapidly variable magnetic field that is orthogonal to the current. Eddy currents generated by the changes of the magnetic field directly affect neurons (Barker, 1999). In addition, it has been known that different stimulation frequencies have different effects on the activities of the cerebral cortex, with high-frequency (> 5 Hz) stimulation facilitating local neuronal excitability and low-frequency (< 1 Hz) stimulation showing inhibitory effects (Lefaucheur, 2006; Butler and Wolf, 2007). Low-frequency rTMS (LF-rTMS) aims at increasing the excitability of the ipsilesional hemisphere by exerting its effects on the disrupted interhemispheric inhibition following stroke and thereby providing inhibitory stimulation to the contralesional hemisphere. Meta-analyses of rTMS in patients with stroke indicate that LF-rTMS is recommended for stroke patients in the chronic phase (> 6 months post-stroke), showing a strong possibility of a significant improvement of their upper limb function (Hsu et al., 2012; Le et al., 2014). In the past, our research group implemented a 15-day treatment protocol consisting of LF-rTMS and an intensive individualized rehabilitation program for patients with upper limb hemiparesis following stroke, and demonstrated a significant improvement of upper limb hemiparesis (Kakuda et al., 2011, 2012, 2016). Furthermore, we investigated the effects of our treatment protocol on brain activity and demonstrated a significant increase in the fMRI laterality index, indicating increased neuronal activity in the ipsilesional hemisphere (Yamada et al., 2013). Our single photon emission computed tomography (SPECT) study also demonstrated a significant decrease in perfusion in the middle frontal gyrus (Brodmann area; BA6), precentralgyrus (BA4), and post central gyrus (BA3) of the contralesional hemisphere, as well as an increased perfusion in the insula (BA13) and precentral gyrus (BA44) of the ipsilesional hemisphere (Hara et al., 2013). Thus, we demonstrated changes in brain activity between pre- and post-treatment that combined LF-rTMS and an intensive occupational therapy (iOT) program.

In recent studies, rTMS was used not only in treating upper limb hemiparesis after stroke, but also for other conditions, including neurological and psychiatric disorders, pain, and Parkinson’s disease (Lefaucheur et al., 2014). Furthermore, some studies conducted neuropsychological examinations at the time of rTMS to evaluate its effect on cognitive function (Nardone et al., 2014; Drumond Marra et al., 2015). One study reported an improvement in cognitive function following rTMS in patients with mild cognitive impairment (Nardone et al., 2014). Drumond Marra et al. (2015) reported an improved performance on the Rivermead Behavioral Memory Test following high-frequency rTMS (HF-rTMS) to the left dorsolateral prefrontal cortex (DLPFC).

Furthermore, the effects of rTMS on cognitive function in addition to motor disorders, aphasia, and affective disorders have been attracting attention (Lefaucheur et al., 2014; Nardone et al., 2014; Drumond Marra et al., 2015). One study reported an improvement in Trail-Making Test part B (TMT-B) performance by HF-rTMS, while another study reported a lack of significant improvement relative to a control group (Moser et al., 2002; Mittrach et al., 2010). However, few studies have investigated the effects of LF-rTMS on cognitive function. As described earlier, LF-rTMS exerts an inhibitory stimulation to the side of administration and is considered to affect the contralateral cerebral cortices via a modulation of interhemispheric inhibition. Therefore, LF-rTMS possibly affects a broader region than that affected by HF-rTMS. Meta-analyses of rTMS in patients with stroke indicate that LF-rTMS is recommended for stroke patients in the chronic phase (> 6 months post-stroke).

Although previous studies indicate a possibility of positive effects of rTMS on cognitive function; however, to the best of our knowledge, there has been no report describing the effect of a combined intervention program of LF-rTMS and intensive occupational therapy (iOT) on cognitive function in post-stroke patients. Therefore, the present study aimed to explore the therapeutic effect of the combined intervention program on patients with post-stroke upper limb hemiparesis.

Continue —> Does a combined intervention program of repetitive transcranial magnetic stimulation and intensive occupational therapy affect cognitive function in patients with post-stroke upper limb hemiparesis? Hara T, Abo M, Kakita K, Masuda T, Yamazaki R – Neural Regen Res

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[ARTICLE] The Effect of rTMS with Rehabilitation on Hand Function and Corticomotor Excitability in Sub-Acute Stroke – Full Text PDF

Abstract:

Objectives: Stroke is the leading cause of long-term disability. Hand motor impairment resulting from chronic stroke may have extensive physical, psychological, financial, and social implications despite available rehabilitative treatments. The best time to start treatment for stroke, is in sub-acute period. Repetitive transcranial magnetic stimulation (rTMS) is a method of stimulating and augmenting the neurophysiology of the motor cortex in order to promote the neuroplastic changes that are associated with motor recovery. The purpose of this study was to compare the effects of repetitive transcranial magnetic stimulation protocols plus routine rehabilitation on hand motor functions and hand corticomotor excitability in stroke patients with hemiplegia with pure routine rehabilitation programs.

Methods: This study was a randomized clinical trial which was performed on 24 patients with hemiplegia who were randomly divided in to three groups. One group (n=7), received high frequency repetitive transcranial magnetic stimulation (Hf rTMS) on lesioned M1 with routine rehabilitation program, and the other group (n=7), received rehabilitation program with low frequency repetitive transcranial magnetic stimulation stimulation (Lf rTMS) on nonlesined M1, and a control group (n=10), who were given only routine rehabilitation programs. The treatment was performed for 10 sessions, three times peri-test, Post and follow-up about neurophysiological contralesional hemisphere evaluations using record of MEP wave indices by single pulse TMS, and assessing functional wolf test and hand grip power of disabled hand by dynamometer.

Results: The results demonstrated that the rest MEP threshold reduction in experimental group which received high frequency magnetic stimulation was statistically significant (P<0.05). There was similar finding for active MEP threshold in the both high and low frequency but not in control group (P<0.05). Also there were more significant relation between obtained results from WOLF test and grip power with MEP mentioned parameters, in high frequency group, but not in low frequency and control group.

Discussion: According to the results, However it seems that Hf rTMS combined with routin physiotherapy can significantly improve hand functions and brain neurophysiology via specifically increase of contralesional corticomotor excitability in sever stroke patients that is representative of the role of neuroplasticity in nonlesioned hemisphere but the hypothesis of movement improvement related cognitive balance can’t be eliminated by exploring powerful approved effect of Hf rTMS on mood regulation.

Source: The Effect of rTMS with Rehabilitation on Hand Function and Corticomotor Excitability in Sub-Acute Stroke – Iranian Rehabilitation Journal

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[Abstract] Safety of repetitive transcranial magnetic stimulation in patients with epilepsy: A systematic review – Epilepsy & Behavior

Highlights

We reviewed the crude risk of seizures and other adverse events of rTMS in patients with epilepsy.

A crude per-subject risk of 2.9% (95% CI: 1.3–4.5) was estimated for seizures occurring during or shortly after.

The safety of rTMS applied to patients with epilepsy appears to be the same as in other conditions.

Abstract

Approximately one-third of patients with epilepsy remain with pharmacologically intractable seizures. An emerging therapeutic modality for seizure suppression is repetitive transcranial magnetic stimulation (rTMS). Despite being considered a safe technique, rTMS carries the risk of inducing seizures, among other milder adverse events, and thus, its safety in the population with epilepsy should be continuously assessed.

We performed an updated systematic review on the safety and tolerability of rTMS in patients with epilepsy, similar to a previous report published in 2007 (Bae EH, Schrader LM, Machii K, Alonso-Alonso M, Riviello JJ, Pascual-Leone A, Rotenberg A. Safety and tolerability of repetitive transcranial magnetic stimulation in patients with epilepsy: a review of the literature. Epilepsy Behav. 2007; 10 (4): 521–8), and estimated the risk of seizures and other adverse events during or shortly after rTMS application.

We searched the literature for reports of rTMS being applied on patients with epilepsy, with no time or language restrictions, and obtained studies published from January 1990 to August 2015. A total of 46 publications were identified, of which 16 were new studies published after the previous safety review of 2007.

We noted the total number of subjects with epilepsy undergoing rTMS, medication usage, incidence of adverse events, and rTMS protocol parameters: frequency, intensity, total number of stimuli, train duration, intertrain intervals, coil type, and stimulation site.

Our main data analysis included separate calculations for crude per subject risk of seizure and other adverse events, as well as risk per 1000 stimuli. We also performed an exploratory, secondary analysis on the risk of seizure and other adverse events according to the type of coil used (figure-of-8 or circular), stimulation frequency (≤1 Hz or >1 Hz), pulse intensity in terms of motor threshold (<100% or ≥100%), and number of stimuli per session (<500 or ≥ 500).

Presence or absence of adverse events was reported in 40 studies (n = 426 subjects). A total of 78 (18.3%) subjects reported adverse events, of which 85% were mild. Headache or dizziness was the most common one, occurring in 8.9%. We found a crude per subject seizure risk of 2.9% (95% CI: 1.3–4.5), given that 12 subjects reported seizures out of 410 subjects included in the analysis after data of patients with epilepsia partialis continua or status epilepticus were excluded from the estimate.

Only one of the reported seizures was considered atypical in terms of the clinical characteristics of the patients’ baseline seizures. The atypical seizure happened during high-frequency rTMS with maximum stimulator output for speech arrest, clinically arising from the region of stimulation. Although we estimated a larger crude per subject seizure risk compared with the previous safety review, the corresponding confidence intervals contained both risks. Furthermore, the exclusive case of atypical seizure was the same as reported in the previous report. We conclude that the risk of seizure induction in patients with epilepsy undergoing rTMS is small and that the risk of other adverse events is similar to that of rTMS applied to other conditions and to healthy subjects.

Our results should be interpreted with caution, given the need for adjusted analysis controlling for potential confounders, such as baseline seizure frequency. The similarity between the safety profiles of rTMS applied to the population with epilepsy and to individuals without epilepsy supports further investigation of rTMS as a therapy for seizure suppression.

Source: Safety of repetitive transcranial magnetic stimulation in patients with epilepsy: A systematic review – Epilepsy & Behavior

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[Abstract] Effects of repetitive transcranial magnetic stimulation on lower extremity spasticity and motor function in stroke patients – Disability and Rehabilitation

Effects of repetitive transcranial magnetic stimulation on lower extremity spasticity and motor function in stroke patientsAbstract

Purpose: To investigate the effect of low-frequency repetitive transcranial magnetic stimulation (rTMS) on lower extremity (LE) spasticity, motor function and motor neurone excitability in chronic stroke patients.
Method: This study was a randomised sham-controlled cross-over trial with 1-week follow-up. A total of 20 post-stroke patients were randomised to receive active (n = 10) or sham (n = 10) rTMS. Fourteen of them (7 in each group) crossed over to the sham or active rTMS after a washout period of 1 month. Interventions consist of five consecutive daily sessions of active or sham rTMS to the unaffected lower extremity motor area (1000 pulses; 1 Hz; 90% of the tibialis anterior motor threshold). Outcome measures were modified modified ashworth scale (MMAS), the H-reflex, lower extremity section of Fugl–Mayer assessment (LE-FMA) and timed UP and GO (TUG) test. All outcomes were measured at three levels in each intervention period: pre- and post-intervention and 1-week follow-up.
Results: Friedman’s test revealed significant improvement in MMAS score only after active rTMS. This improvement lasted for one week after the active rTMS. Repeated measure analysis of variance (ANOVA) showed significant time*intervention interaction for LE-FMA. There are no differences between groups for the MMAS and LE-FMA. No significant change inHmax/Mmax ratio and TUG test was noted.
Conclusion: Low-frequency rTMS over the LE motor area can improve clinical measures of muscle spasticity and motor function. More studies are needed to clarify the changes underlying this improvement in spasticity.

  • Implications for Rehabilitation

  • Spasticity is a common disorder and one of the causes of long-term disability after stroke.

  • Physical therapy modalities, oral medications, focal intervention and surgical procedures have been used for spasticity reduction.

  • Beneficial effect of the repetitive transcranial magnetic stimulation (rTMS) for post-stroke upper extremity spasticity reduction and motor function improvement was demonstrated in previous studies.

  • This study shows amelioration of lower extremity spasticity and motor function improvement after five daily sessions of inhibitory rTMS to the unaffected brain hemisphere which lasted for at least 1 week following the intervention.

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Source: Effects of repetitive transcranial magnetic stimulation on lower extremity spasticity and motor function in stroke patients – Disability and Rehabilitation –

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