Repetitive Peripheral Magnetic Stimulation With Intensive Swallowing Rehabilitation for Poststroke Dysphagia: An Open-Label Case Series

Advances in biotechnology and clinical therapy in the field of peripheral nerve regeneration based on magnetism

Peripheral nerve injury (PNI) is one of the most common neurological diseases. Recent studies on nerve cells have provided new ideas for the regeneration of peripheral nerves and treatment of physical trauma or degenerative disease-induced loss of sensory and motor neuron functions. Accumulating evidence suggested that magnetic fields might have a significant impact on the growth of nerve cells. Studies have investigated different magnetic field properties (static or pulsed magnetic field) and intensities, various magnetic nanoparticle-encapsulating cytokines based on superparamagnetism, magnetically functionalized nanofibers, and their relevant mechanisms and clinical applications. This review provides an overview of these aspects as well as their future developmental prospects in related fields.

Dosages of swallowing exercises in stroke rehabilitation: a systematic review

PURPOSE

To investigate the dosages of swallowing exercises reported in intervention studies on post-stroke dysphagia through systematic review.

METHODS

Five electronic databases were searched from inception until February 2022 with reference tracing of included studies. Studies were included, where adults with post-stroke dysphagia received rehabilitative, behavioural swallowing exercises, pre/post outcomes were reported, and intervention dosage was described in detail, including frequency, intensity, time, and type of exercise. Two reviewers independently screened studies and rated quality using ASHA Levels of Evidence tool. Data was tabulated and narratively described.

RESULTS

54 studies were included with a total 1501 participants. Studies included 28 randomised controlled trials, 8 non-randomised controlled trials, 12 pre/post studies, 3 retrospective case controls and 3 case studies. Results showed inconsistent reporting of intervention dosage, with intensity the least consistently reported dosage component. While swallowing intervention was most commonly provided five times per week for four weeks, there was a wide breadth of type, frequency, intensity and duration of swallowing exercises reported. Dosage under-reporting and variation was particularly observed in "standard care" co-interventions or control groups. Study strengths included following PRISMA guidelines, providing a comprehensive review of swallowing exercise methodology and dosages, and including non-English studies. The limitation was lack of meta-analysis due to the heterogeneity of included studies.

CONCLUSIONS

Dosages of swallowing exercises are inconsistently reported and vary significantly in post-stroke dysphagia studies. Results indicate the need for consistent and comprehensive dosage reporting in dysphagia studies, and for further research into evidence-based principles to optimise swallowing exercise dosages.

SYSTEMATIC REVIEW REGISTRATION NUMBER

131294.

Effect of Peripheral Magnetic Stimulation for Dysphagia Rehabilitation: A Systematic Review

Recently, a therapeutic method to stimulate the suprahyoid muscle using peripheral magnetic stimulation for dysphagia rehabilitation has been reported. However, clinical evidence, application protocol, and intervention method remain unclear. Therefore, a systematic review of the published literature is needed. The objective of this study was to systematically review clinical studies of peripheral magnetic stimulation applied for rehabilitation of dysphagia. Issues to be considered in future studies are also suggested. This systematic review performed a literature search of four databases (Medline, Embase, CINAHL, and Web of Science) to identify relevant studies published on the application of repetitive peripheral magnetic stimulation (rPMS) for swallowing-related muscles between 2010 and 2022. Seven studies were reviewed. Randomized controlled trials and one-group pre-post, case study designs were included. In the included studies, rPMS was applied to strengthen the submental suprahyoid muscles. The intervention regime varied. The rPMS was applied at a frequency of 30 Hz for 2 s. Rest time ranged from 8 s to 27-28 s. The number of intervention sessions ranged from 2-3 to 30. The intensity ranged from pain-inducing minimum intensity (90% of maximum stimulus output) to non-painful intensity (70-80% of maximum intensity). The rPMS on the suprahyoid muscles had positive effects on physiological changes in the swallowing function, such as displacement of the hyoid bone, muscle strength (cervical flexor, jaw-opening force), swallowing safety, swallowing performance, and swallowing-related quality of life. Participants also reported little pain and adverse reactions during rPMS. Although rPMS is a therapeutic option that can help improve the swallowing function as a non-invasive stimulation method in the rehabilitation of dysphagia, clinical evidence is needed for the development of clear stimulation protocols and guidelines.

Clinical effect of repetitive transcranial magnetic stimulation on dysphagia due to stroke

BACKGROUND

Repetitive transcranial magnetic stimulation (rT) could change the excitability of the cerebral cortex, and control the neurotransmitter release, with the therapeutic effect depending on stimulation intensity and position. In this study, we used 3 Hz rTMS to stimulate the pharyngeal cortical area of the lesioned hemisphere and to explore its clinical significance in the treatment of dysphagia after acute cerebral infarction.

METHODS

A total of 61 in-patients with acute dysphagia caused by cerebral infarction hospitalized in the department of neurology of our hospital were included in this study and were assigned into the control and rTMS group. Patients in the control group only accepted the basic treatment of rehabilitation training, while patients in the rTMS group received additional rTMS (3 Hz) stimulation. The levels of the water swallowing test (WST) 14 days before and after the treatment of rTMS (3 Hz) would be recorded.

RESULTS

After different therapies in two groups, 9 patients of the control group showed excellent curative effect, with a recovery rate of 31.0%. However, in the rTMS group, the swallowing function of 21 patients was significantly improved, with a recovery rate of 65.6%. Comparison results showed that the recovery rate of the rTMS group was much better than the control group (P < 0.05), indicating an effective therapeutic effect of 3 Hz rTMS on patients with dysphagia after acute cerebral infarction.

CONCLUSION

Stimulating the target cortical representation areas of pharyngeal of the lesioned hemisphere with cerebral infarction by the rTMS (3 Hz) could improve the patients' function.

Checklist on the Quality of the Repetitive Peripheral Magnetic Stimulation (rPMS) Methods in Research: An International Delphi Study

An increasing number of clinical research studies have used repetitive peripheral magnetic stimulation (rPMS) in recent years to alleviate pain or improve motor function. rPMS is non-invasive, painless, and administrated over peripheral nerve, spinal cord roots, or a muscle using a coil affixed to the skin and connected to a rapid-rate magnetic stimulator. Despite the clinical impact and scientific interest, the methodological inconsistencies or incomplete details and findings between studies could make the rPMS demonstration difficult to replicate. Given the lack of guidelines in rPMS literature, the present study aimed at developing a checklist to improve the quality of rPMS methods in research. An international panel of experts identified among those who had previously published on the topic were enrolled in a two-round web-based Delphi study with the aim of reaching a consensus on the items that should be reported or controlled in any rPMS study. The consensual rPMS checklist obtained comprises 8 subject-related items (e.g., age, sex), 16 methodological items (e.g., coil type, pulse duration), and 11 stimulation protocol items (e.g., paradigm of stimulation, number of pulses). This checklist will contribute to new interventional or exploratory rPMS research to guide researchers or clinicians on the methods to use to test and publish rPMS after-effects. Overall, the checklist will guide the peer-review process on the quality of rPMS methods reported in a publication. Given the dynamic nature of a consensus between international experts, it is expected that future research will affine the checklist.

Repetitive peripheral magnetic stimulation combined with intensive physical therapy for gait disturbance after hemorrhagic stroke: an open-label case series

In this pilot study, we aimed to determine the safety and feasibility of a 15-day protocol consisting of in-hospital repetitive peripheral magnetic stimulation (rPMS) combined with intensive physical therapy for the recovery of the gait disturbance in chronic stroke patients with lower limb hemiparesis. Seven hemorrhagic stroke patients with lower limb hemiparesis and gait disturbance (age: 50-78; time from onset of stroke: 7-107 months) were enrolled. rPMS was applied to the muscles of the paretic lower limb with a parabolic coil. A train of stimuli at a frequency of 20 Hz was applied for 3 s followed by a 27-s rest interval. Therapy with rPMS was performed with eighty such trains of stimuli (total 4800 pulses). Following rPMS therapy, 120 min of physical therapy was administrated daily. Each patient received this combination treatment over fifteen consecutive days, with the walking function of all participants assessed before and after the intervention. The proposed treatment protocol resulted in significant improvements in the walking speed, ambulation ability, and balance ability, but showed no significant effects on the endurance capacity, step length, and spasticity. No rPMS-related side effects were noted. Our protocol consisting of rPMS and intensive physical therapy appears well tolerated and feasible for therapy in hemorrhagic stroke patients with gait disturbance. Further large-scale studies are required to confirm its efficacy.

Dose-response of rPMS for upper Limb hemiparesis after stroke

INTRODUCTION

Repetitive peripheral magnetic stimulation (rPMS) therapy is an innovative and minimally invasive neurorehabilitative technique and has been shown to facilitate neural plasticity. However, there is at present no research that clarifies the dose-response of rPMS therapy on the recovery of upper limb hemiparesis after stroke. This trial aims to clarify the dose-response of rPMS therapy combined with intensive occupational therapy (OT) for chronic stroke patients with moderate to severe upper limb hemiparesis.

METHODS AND ANALYSIS

This multicenter, prospective, assessor-blinded, randomized controlled study with 3 parallel groups will be conducted from January 20, 2020 to September 30, 2022. Fifty patients will be randomly assigned in a ratio of 1:2:2 to the control group, the group receiving daily 2400 pulses of rPMS, or the group receiving daily 4800 pulses of rPMS, respectively. From the day after admission (Day 1), rPMS therapy and intensive OT will be initiated. The primary outcome is the change in the motor function of the affected upper extremity (Fugl-Meyer Assessment) between the time of admission (Day 0) and the day after 2 weeks of treatment (Day 14). Secondary outcomes will include the changes in spasticity, active range of motion, motor evoked potential, and activity of daily living.

ETHICS AND DISSEMINATION

The study was approved by the Jikei University Certified Review Board for all institutions (reference number: JKI19-020). Results of the primary and secondary outcomes will be published in a peer-reviewed journal and presented at international congresses. The results will also be disseminated to patients.

TRIAL REGISTRATION NUMBER

jRCTs032190191.