Long-term analyses of spastic muscle behavior in chronic poststroke patients after near-infrared low-level laser therapy (808 nm): a double-blinded placebo-controlled clinical trial

Neuromodulation technologies improve functional recovery after brain injury: From bench to bedside

Spontaneous recovery frequently proves maladaptive or insufficient because the plasticity of the injured adult mammalian central nervous system is limited. This limited plasticity serves as a primary barrier to functional recovery after brain injury. Neuromodulation technologies represent one of the fastest-growing fields in medicine. These techniques utilize electricity, magnetism, sound, and light to restore or optimize brain functions by promoting reorganization or long-term changes that support functional recovery in patients with brain injury. Therefore, this review aims to provide a comprehensive overview of the effects and underlying mechanisms of neuromodulation technologies in supporting motor function recovery after brain injury. Many of these technologies are widely used in clinical practice and show significant improvements in motor function across various types of brain injury. However, studies report negative findings, potentially due to variations in stimulation protocols, differences in observation periods, and the severity of functional impairments among participants across different clinical trials. Additionally, we observed that different neuromodulation techniques share remarkably similar mechanisms, including promoting neuroplasticity, enhancing neurotrophic factor release, improving cerebral blood flow, suppressing neuroinflammation, and providing neuroprotection. Finally, considering the advantages and disadvantages of various neuromodulation techniques, we propose that future development should focus on closed-loop neural circuit stimulation, personalized treatment, interdisciplinary collaboration, and precision stimulation.

A modified scoping review of interventions for global post stroke spasticity

PURPOSE

Stroke is a major global health concern, and post-stroke spasticity (PSS) can severely impair mobility and quality of life. This modified scoping review synthesizes the most current evidence up to 2024 for interventions targeting PSS, employing GRADE methodology and a packed bubble chart adapted from the Evidence Alert Traffic Light System to rigorously evaluate the state of evidence to assist global healthcare professionals and policymakers in developing context-sensitive strategies that are both effective and feasible within their specific healthcare environments.

METHODS

From a pool of 2420 studies, 53 met our inclusion criteria and were subjected to a detailed analysis, representing 44 distinct interventions.

FINDINGS

In our findings, oral medications showed limited efficacy with potential adverse effects. Therefore, prioritizing GRADE A treatments with green traffic light like low-dose botulinum toxin type A (BoNT-A) injections, early intervention, and multimodal therapies of GRADE A can significantly reduce spasticity, as well as alleviate pain and shed light to enhance functional recovery. These treatments offer the additional advantage of requiring minimal therapy duration and personnel. Intrathecal baclofen (ITB) has demonstrated efficacy in managing severe spasticity following bilateral strokes, surpassing the effectiveness of oral medicines. Nevertheless, in settings with limited resources, therapies graded from A to C and indicated by green to yellow traffic lights can still be employed to control spasticity and accomplish rehabilitation goals, even though they require daily sessions that demand substantial time and personnel.

SUMMARY

Our study provides valuable insights into efficacious therapies for PSS and highlights areas requiring additional research to enhance clinical decision-making.

Long-Term Enhancement of Botulinum Toxin Injections for Post-Stroke Spasticity by Use of Stretching Exercises-A Randomized Controlled Trial

Botulinum toxin A (BONT/A) injections play a central role in the treatment of upper limb spasticity in stroke patients. We proposed structured stretching exercises to enhance the effect of post-stroke spasticity relief of the upper limbs following BONT/A injections. A total of 43 patients who had a stroke with grade 2 spasticity or higher on the Modified Ashworth Scale (MAS) in their upper-limb muscles were randomly assigned to the intervention (n = 21) or control group (n = 22). The former received structured stretching exercises after their BONT/A injections for 20 min, 5 days per week, for 6 months at a hospital, while the others conducted self-stretching exercises at home. The outcome measures were assessed before the intervention (T0) and after three (T1) and six months (T2). Significantly greater improvements in the MAS scores of the elbows, wrists, and fingers were found in the intervention group's patients at T1 and T2. The behavioral outcome measures, including shoulder pain, activities of daily living, and quality of life, and our electrophysiological studies also showed a significantly higher enhancement in this patient group. In conclusion, the structured stretching exercises plus BONT/A injections for six months showed a superior effect in relieving post-stroke upper-limb spasticity compared to self-stretching exercises.

Phototherapy for age-related brain diseases: Challenges, successes and future

Brain diseases present a significant obstacle to both global health and economic progress, owing to their elusive pathogenesis and the limited effectiveness of pharmaceutical interventions. Phototherapy has emerged as a promising non-invasive therapeutic modality for addressing age-related brain disorders, including stroke, Alzheimer's disease (AD), and Parkinson's disease (PD), among others. This review examines the recent progressions in phototherapeutic interventions. Firstly, the article elucidates the various wavelengths of visible light that possess the capability to penetrate the skin and skull, as well as the pathways of light stimulation, encompassing the eyes, skin, veins, and skull. Secondly, it deliberates on the molecular mechanisms of visible light on photosensitive proteins, within the context of brain disorders and other molecular pathways of light modulation. Lastly, the practical application of phototherapy in diverse clinical neurological disorders is indicated. Additionally, this review presents novel approaches that combine phototherapy and pharmacological interventions. Moreover, it outlines the limitations of phototherapeutics and proposes innovative strategies to improve the treatment of cerebral disorders.

Recent advances in light energy biotherapeutic strategies with photobiomodulation on central nervous system disorders

Transcranial photobiomodulation refers to irradiation of the brain through the skull using low-intensity red or near-infrared light, which is the most commonly studied method of light energy biotherapy for central nervous system disorders. The absorption of photons by specific chromophores within the cell elevates ATP synthesis, reduces oxidative stress damage, alleviates inflammation or mediates the activation of transcription factors and signaling mediators through secondary mediators, which in turn trigger downstream signaling pathways to cause a series of photobiological effects including upregulation of neurotrophic factors. Multiple mechanisms are simultaneously involved in the pathological process of central nervous system disorders. The pleiotropic treatment of transcranial photobiomodulation towards multiple targets plays a beneficial role in improving hemodynamics, neural repair and improving behaviors in central nervous system disorders such as ischemic stroke, traumatic brain injury, neurodegenerative diseases, epilepsy and depression. This review mainly introduces the mechanism and recent preclinical and clinical advances of transcranial photobiomodulation for central nervous system disorders, which will provide a reference for clinicians to understand and engage in related studies, and calls for more and larger studies to validate and develop a wider application of transcranial photobiomodulation in central nervous system.

Transcranial photobiomodulation therapy associated with cardiorespiratory rehabilitation in spastic subjects

The objective of this study was to evaluate the effects of cardiorespiratory rehabilitation (CR) and transcranial photobiomodulation (tPBM) on exercise tolerance (ET), heart rate variability (HRV), and peripheral muscle activity in individuals with spasticity. Fifteen participants with spasticity were randomly assigned to two groups: the tPBM group (tPBMG) consisted of eight volunteers who underwent tPBM (on mode) and CR, while the control group (CG) consisted of seven volunteers who underwent simulated tPBM (off mode) and CR. The CR program included 12 weeks of treatment, twice a week for one hour, involving aerobic exercises and lower limb strengthening. For tPBM, a cluster with three lasers (λ = 680 nm, 808 nm), with a power of 100 mW/laser and energy of 36 J, applied to the F7, F8, and Fpz points. The following parameters were evaluated after 8 and 12 weeks: ET, HRV, and surface electromyography (EMG) of the rectus femoris muscle during orthostasis (ORT), isometric squatting (ISOM), and isotonic squatting (ISOT). Both groups showed a 40% increase in ET for the CG and a 30% increase for the tPBMG. The CG had more pronounced parasympathetic modulation alterations during post-exercise effort and recovery compared to the tPBMG. The EMG results showed that the tPBMG exhibited progressive improvement in muscle activity during ISOM and ISOT, as well as a decrease in the interlimb difference. In conclusion, both CR and tPBMG demonstrated improvements in ET. However, tPBMG specifically showed promising effects on HRV modulation and peripheral muscle electrical activity, providing additional benefits compared to CR alone.

Safety and Clinical Impact of a Single Red Light Irradiation on Breast Tumor-Bearing Mice

Low-level light therapy has been used in health care as a therapeutic strategy for different diseases. However, its effects on cancer are controversial. This work evaluated the effects of three energies on breast cancer-bearing mice after a single red light-emitting diode (LED) irradiation. 4T1 cells were inoculated into the mammary fat pad of female BALB/c mice. When tumor volume reached 100 mm³ , animals were irradiated by a LED irradiator (660 ± 11 nm) with energies of 1.2, 3.6, and 6.0 J. Control without irradiation and healthy animals were also evaluated. Mice were monitored regarding tumor volume and total blood count. After euthanasia, their organs were examined. We observed that a single irradiation does not increase tumor volume. All irradiated groups exhibited better clinical conditions than control, which presented a significant decrease in platelet and red blood cell levels compared with healthy mice. The energy of 3.6 J arrested neutrophil-lymphocyte rate besides promoting longer survival and a lower number of metastatic nodules in the lungs. These findings suggest that a single red LED irradiation causes no impact on the course of the disease. Besides, the intermediary dose-effect should be further investigated since it seems to promote better outcomes on breast cancer-bearing mice.

Post-stroke fatigue: a scoping review

Background: Post-stroke fatigue (PSF) is one of the most common and frustrating outcomes of stroke. It has a high prevalence and it can persist for many years after stroke. PSF itself contributes to a wider range of undesirable outcomes that affect all aspects of daily life. The aim of this review was to identify and summarise the most recent research on PSF, in order to update the evidence base. Methods: We updated an existing review (Hinkle et al. 2017) systematically searching CINAHL, MEDLINE, PsycINFO, and PubMed to cover new research studies between 1 st March 2016 and the search date (19 th January 2020). We included interventional and observational research, and clinical practice guidelines that were not covered in the original review. After duplicate removal in EndNote, two reviewers screened the search results in Rayyan, and data from eligible full texts were extracted onto an Excel spreadsheet. Finally, we used RobotReviewer and a human reviewer to assess the risk of bias of randomised trials for this scoping review. Results: We identified 45 records for 30 studies (14 observational, 10 interventional studies, and 6 guidelines). Apart from one, the interventional studies were single-centred, had high risk of bias and small sample size (median 50). They investigated exercise, pharmacotherapy, psychotherapy, education, and light therapy. Observational studies mainly reported the factors related to PSF including co-morbidities, depression and anxiety, quality of life, activities of daily living, stroke severity, medication use and polypharmacy, polymorphism, pain, apathy, limb heaviness, neuroticism, mobility, and thyroid-stimulating hormone. Guidelines either did not report on PSF or, when reported, their recommendations were supported by little or low level of evidence. Conclusion: Although we identified a number of recent studies which have added to our current knowledge on PSF, none are robust enough to change current clinical practice.

Post-stroke fatigue: a scoping review

Background: Post-stroke fatigue (PSF) is one of the most common and frustrating outcomes of stroke. It has a high prevalence and it can persist for many years after stroke. PSF itself contributes to a wider range of undesirable outcomes that affect all aspects of daily life. The aim of this review was to identify and summarise the most recent research on PSF, in order to update the evidence base. Methods: We updated an existing review (Hinkle et al. 2017) systematically searching CINAHL, MEDLINE, PsycINFO, and PubMed to cover new research studies between 1 st March 2016 and the search date (19 th January 2020). We included interventional and observational research, and clinical practice guidelines that were not covered in the original review. After duplicate removal in EndNote, two reviewers screened the search results in Rayyan, and data from eligible full texts were extracted onto an Excel spreadsheet. Finally, we used RobotReviewer and a human reviewer to assess the risk of bias of randomised trials for this scoping review. Results: We identified 45 records for 30 studies (14 observational, 10 interventional studies, and 6 guidelines). Apart from one, the interventional studies were single-centred, had high risk of bias and small sample size (median 50). They investigated exercise, pharmacotherapy, psychotherapy, education, and light therapy. Observational studies mainly reported the factors related to PSF including co-morbidities, depression and anxiety, quality of life, activities of daily living, stroke severity, medication use and polypharmacy, polymorphism, pain, apathy, limb heaviness, neuroticism, mobility, and thyroid-stimulating hormone. Guidelines either did not report on PSF or, when reported, their recommendations were supported by little or low level of evidence. Conclusion: Although we identified a number of recent studies which have added to our current knowledge on PSF, none are robust enough to change current clinical practice.