Laser phototherapy (780 nm), a new modality in treatment of long-term incomplete peripheral nerve injury: a randomized double-blind placebo-controlled study

Laser light: Illuminating the path to enhanced periodontal care

The utilisation of laser technology in the realm of periodontal care represents a significant advancement in clinical practice. This article delves into the historical context of laser therapy in medicine, from its inception in 1960 to its evolution into low-level laser therapy (LLLT). LLLT, often referred to as photobiomodulation (PBM), has garnered attention due to its potential to enhance periodontal treatment outcomes. The article thoroughly examines the mechanisms of action of photobiomodulation therapy PBM(T), covering its impact on cellular and tissue levels. The authors explore the evidence-based recommendations for the use of PBM(T) in periodontal care, shedding light on its potential to improve periodontal conditions, especially when applied as an adjunct to conventional treatments. They investigate the role of PBM(T) in individuals and its possible contribution to periodontal health. Additionally, the article delves into its application in periodontal regenerative procedures and its ability to expedite soft tissue wound healing and the effects of PBM(T) in reducing periodontal inflammation and mitigating post-periodontal surgery discomfort. In conclusion, the article calls for enhanced clinical research to streamline laser procedures, develop antimicrobial photodynamic therapy, and conduct well-designed randomised controlled trials (RCTs). It also emphasises the importance of understanding the impact of laser therapy on therapeutic and biological goals, the potential to reduce invasive procedures, and the necessity of adequate research funding.

Comparison of the Effects of Botulinum Toxin Doses on Nerve Regeneration in Rats with Experimentally Induced Sciatic Nerve Injury

This study was designed to compare the effects of various doses of botulinum neurotoxin A (BoNT/A) on nerve regeneration. Sixty-five six-week-old rats with sciatic nerve injury were randomly allocated to three experimental groups, a control group, and a sham group. The experimental groups received a single session of intraneural BoNT/A (3.5, 7.0, or 14 U/kg) injection immediately after nerve-crushing injury. The control group received normal intraneural saline injections after sciatic nerve injury. At three, six, and nine weeks after nerve damage, immunofluorescence staining, an ELISA, and toluidine blue staining was used to evaluate the regenerated nerves. Serial sciatic functional index analyses and electrophysiological tests were performed every week for nine weeks. A higher expression of GFAP, S100β, GAP43, NF200, BDNF, and NGF was seen in the 3.5 U/kg and 7.0 U/kg BoNT/A groups. The average area and myelin thickness were significantly greater in the 3.5 U/kg and 7.0 U/kg BoNT/A groups. The sciatic functional index and compound muscle action potential amplitudes exhibited similar trends. These findings indicate that the 3.5 U/kg and 7.0 U/kg BoNT/A groups exhibited better nerve regeneration than the 14 U/kg BoNT/A and control group. As the 3.5 U/kg and the 7.0 U/kg BoNT/A groups exhibited no statistical difference, we recommend using 3.5 U/kg BoNT/A for its cost-effectiveness.

The Potential Effects of Light Irradiance in Glaucoma and Photobiomodulation Therapy

Human vision is mediated by the retina, one of the most critical tissues in the central nervous system. Glaucoma is a complex retinal disease attributed to environmental, genetic, and stochastic factors, all of which contribute to its pathogenesis. Historically, glaucoma had been thought of primarily as a disease of the elderly; however, it is now becoming more problematic as the incidence rate increases among young individuals. In recent years, excessive light exposure has been suggested as contributing to the rise in glaucoma among the younger generation. Blue light induces mitochondrial apoptosis in retinal ganglion cells, causing optic damage; red light increases cytochrome c oxidase activity in the electron transport system, reducing inflammation and increasing antioxidant reactions to promote cell regeneration. In conclusion, the minimization of blue light exposure and the general application of red light treatment strategies are anticipated to show synergistic effects with existing treatments for retinal disease and glaucoma and should be considered a necessary prospect for the future. This review introduces the recent studies that support the relationship between light exposure and the onset of glaucoma and discusses new treatments, such as photobiomodulation therapy.

Effects of systemic vascular photobiomodulation using LED or laser on sensory–motor recovery following a peripheral nerve injury in Wistar rats

Peripheral nerve injury (PNI) is associated with considerable functional impairment. Photobiomodulation (PBM) has demonstrated positive effects regarding neuromuscular repair after PNI when applied locally to the nerve or injured muscle. However, the effects of systemic PBM with transcutaneous application over an important artery, which is also denominated vascular PBM (VPBM), remain unclear. The aim of the study was to compare the effects of VPBM with low-level laser (LLL) and light-emitting diode (LED) on gait, sensitivity and muscle morphology following a PNI. PNI was induced on Wistar rats using the sciatic nerve crushing technique. VPBM was performed over the rat's artery tail region with LED (850 nm, 40 mW, 3.2 J) and LLL (780 nm, 40 mW, 3.2 J). Gait functionality, mechanical (nociceptive) sensitivity, and morphology of the tibialis anterior muscle were evaluated at 7, 14, and 21 days after injury. An improvement in functional gait was shown in the VPBM-LLL group in all periods. Motor sensitivity was found after 14 days in the VPBM-LLL group. The left/right (L/R) muscle mass ratio revealed a reduction in muscle atrophy in the VPBM-LLL group at 7 days. Muscle fiber diameter increased in the VPBM-LED group at 14 days and increases in the cross-section area were found in the VPBM-LED and VPBM-LLL groups at 7 days. VPBM with both light sources (LED and LLL) positively modulated functioning and neuromuscular recovery following sciatic nerve injury in rats, with more pronounced results when using LLL.

Effects of Laser Acupuncture Therapy for Patients With Inadequate Recovery From Bell's Palsy: Preliminary Results From Randomized, Double-Blind, Sham-Controlled Study

Introduction: Inadequate recovery from Bell's palsy exists in a third of patients and results in physical and social impairments. The controversial nature of existing medical treatment options means that novel, alternative approaches are needed. In basic and clinical studies, low-level laser therapy (LLLT) has proven successful in regenerating peripheral nerves. Laser acupuncture therapy (LAT) is a rapidly growing treatment modality; however, its effectiveness for treating chronic Bell's palsy is unknown. The feasibility of this innovative approach is the focus of this pilot study. Methods: A two-armed, parallel, randomized, investigator-subject-assessor-blinded, sham-controlled pilot study was conducted, and 17 eligible subjects were randomly allocated to either LAT (n=8) or sham LAT (n=9). The LAT group received three treatments each week for six weeks (18 sessions), while the sham LAT group received the same procedure but with a sham laser device. The change from baseline to week 6 in the social subscale of the Facial Disability Index (FDI) was the primary outcome. Secondary outcomes were changes in the House-Brackmann facial paralysis scale (HB), the Sunnybrook facial grading system (SB) and a stiffness scale at weeks 3 and 6. Results: A significant difference was shown in the HB score (P=0.0438) between baseline and week 3 and borderline significance was observed in both SB and stiffness scores from baseline to week 6 (P=0.0598 and P=0.0980 respectively). There was no significant difference in the FDI score between baseline and week 6. Conclusion: To the best of our knowledge, this clinical trial is the first such investigation on this topic. Our findings suggest that using LAT may have clinical effects on long-term complications of Bell's palsy and justify further large-scale studies.

Post-Mastectomy Pain Syndrome: An Up-to-Date Review of Treatment Outcomes

BACKGROUND

Post-mastectomy pain syndrome (PMPS) is a known debilitating surgical complication. While research on prevention, risk factors, and treatments have been conducted, there remains no cohesive treatment paradigm. The aim of our study is to synthesize the existing evidence on PMPS treatment, which may facilitate the implementation of standardized, effective management strategies.

METHODS

Using Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, a comprehensive search was developed and translated for MEDLINE, Cochrane Library, EMBASE, CINAHL, PsycINFO, Web of Science, and ClinicalTrials.gov. The databases were searched using a combination of free terms, phrase searching, and database-specific controlled vocabulary related to PMPS. All unique records were by two independent reviewers. Publications on chronic (>3 months duration) pain after breast cancer-related surgery were included. Limited case series, case reports, and editorials were not included.

RESULTS

A total of 3402 articles from the years 1946-2019 resulted from the literature search after deduplication. Twenty-seven articles met final inclusion criteria for analysis, which revealed 10 major treatment modalities: fat grafting, neuroma surgery, lymphedema surgery, nerve blocks and neurolysis, laser, antidepressants, neuromodulators, physical therapy, mindfulness-based cognitive therapy, and capsaicin.

CONCLUSIONS

In this review, we present a comprehensive assessment of the treatments available for PMPS that may help guide breast surgeons and reconstructive surgeons to employ the most effective treatment strategies for these patients. This review supports the importance of multimodal, multidisciplinary care in improving the management of PMPS.

Transvaginal Photobiomodulation for the Treatment of Chronic Pelvic Pain: A Pilot Study

Background: Chronic pelvic pain (CPP) is a common and debilitating condition that affects millions of U.S. women. Most treatments are ineffective and innovative new therapies are desperately needed. Large, controlled studies show that photobiomodulation (PBM) can reduce pain in patients with other chronic pain conditions, such as low back pain, neck pain, and fibromyalgia. The objective of this pilot study was to determine if transvaginal PBM (TV-PBM) can reduce pain in women with CPP. Methods: We conducted a before and after, observational, pilot study. Patients completed the Short Form-McGill Pain Questionnaire (SF-MPQ) at baseline, 1 week, 3 months, and 6 months after nine treatments of TV-PBM. Clinicians completed the Clinical Global Impression Scale (CGI) assessing patient illness severity at the same time. Wilcoxon rank-sum t-tests and effect size using Cohen's d coefficient (low effect size if d < 0.2, medium if 0.2 < d > 8, and high if d > 0.8) was used to measure degree of pain improvement, which was also considered clinically significant if pain reduction was >30%. Results: Thirteen women completed 9 treatments, and 10 women were successfully followed to 6 months. At baseline, the mean SF-MPQ score was 19.7 (standard deviation [SD] ± 5.9). Compared with baseline, 60% improved; the mean SF-MPQ score decreased to 10.0 (SD ±7.5, p = 0.004, d = 1.6) at 1 week after treatment, to 9.7 (SD ±7.9, p = 0.005, d = 1.7) at 3 months, and 8.2 (SD ±8.1, p = 0.002, d = 1.9) at 6 months. Conclusion: Transvaginal PBM provided significant and sustained pain relief to women with CPP up to 6 months. Further controlled studies are needed to confirm these findings, however, in this initial pilot, TV-PBM shows promise.

"At-Home" Photobiomodulation: A New Approach for Bell's Palsy Treatment

Objective

This report is the first one to describe the possibility to use “self‐administered” photobiomodulation (PBM) for Bell's palsy (BP) treatment.

Background

BP is a peripheral disorder of the facial nerve causing sudden paralysis of unilateral facial muscles, and PBM has been successfully suggested for its treatment without any side effect. This is the first case report where a laser device was successfully used at home by the patient herself to treat BP opening new perspectives on the therapy of this disease.

Methods

This report describes the “at-home PBM” treatment performed on a 15-year-old girl who presented BP consisting of acute pain on the right side of her face, difficulty in biting and dripping saliva from the right side of her lips. The treatment was performed twice a day by cutaneous applications, each of 15 minutes (total fluence 48 J/cm²) in an area corresponding to the parotid gland by a device emitting at 808 nm at 250 mW output power.

Results

Two weeks after PBM treatment, performed at home twice a day by the patient herself without any kind of pharmacological therapy, the complete disappearing of the disease was noticed with no side effects.

Conclusion

With the limitations due to a single case report and with the need of further clinical trials to confirm it, “at-home PBM” seems to represent a good and safe approach to the treatment of BP.

Physical therapeutic treatment for traumatic brachial plexus injury in adults: A scoping review

Traumatic brachial plexus injury (BPI) is one of the most disabling injuries of the upper extremity, often requiring specialized treatment and a prolonged rehabilitation period. This scoping review was carried out to identify and describe the physical therapy modalities applied in the rehabilitation of adult individuals with BPI. Electronic databases, gray literature, and reference lists were searched, and studies meeting the following eligibility criteria were included: (a) interventions including any physical therapy modality; (b) individuals age ≥18 years old; and (c) a clinical diagnosis of BPI. The literature search yielded 681 articles of which 49 met the inclusion criteria and had their outcomes, treatment parameters, and the differences between conservative and pre- and postoperative treatment phases analyzed. The most commonly used physical therapy interventions were in the subfields of kinesiotherapy (ie, involving range of motion exercises, muscle stretching, and strengthening), electrothermal and phototherapy, manual therapy, and sensory re-education strategies. Although several physical therapy modalities were identified for the treatment of BPI in this scoping review, the combination of low levels of evidence and the identified gaps regarding the treatment parameters challenge the reproducibility of such treatments in clinical practice. Therefore, future controlled clinical trials with clearer treatment protocols for individuals with BPI are needed.

Effects of 660-nm and 780-nm Laser Therapy on ST88-14 Schwann Cells

The aim of the present study was to evaluate the comparative effects of red (660-nm) and near-infrared (780-nm) low-level laser therapy (LLLT) on viability, mitochondrial activity, morphology and gene expression of growth factors on Schwann cells (SC). ST88-14 cells were grown in RPMI 1640 with 10 mM of HEPES, 2 mM of glutamine, 10% fetal bovine serum and 1% antibiotic-antimycotic solution at 37°C in humidified atmosphere of 5% CO₂ . Cells were detached with trypsin and centrifugated at 231 g for 5 min at 10°C, and the pellet (8 × 10⁴  cells/tube) was irradiated at the bottom of 50 ml polypropylene tube with a Twin-Laser system (660 and 780 nm, 40 mW, 1 mW cm^-2 , 3.2 and 6.4 J, 80 and 160 J cm^-2 with 80 and 160 s). After 1, 3 and 7 days, the analysis was performed. After irradiation, the SC increase mitochondrial activity, gene expression of the neural growth factors NGF and BDNF, and cell migration and increase the G2/M cells. SC showed neuronal morphology, normal F-actin cytoskeleton organization and positive labeling for S100. PBM increased metabolic activity, mitosis and gene expression when irradiated with red and infrared LLLT. An increase in cell migration was obtained when irradiated with infrared LLLT.

Additive Manufacturing of Nerve Guidance Conduits for Regeneration of Injured Peripheral Nerves

As a common and frequent clinical disease, peripheral nerve defect has caused a serious social burden, which is characterized by poor curative effect, long course of treatment and high cost. Nerve autografting is first-line treatment of peripheral nerve injuries (PNIs) but can result in loss of function of the donor site, neuroma formation, and prolonged operative time. Nerve guidance conduit (NGC) serves as the most promising alternative to autologous transplantation, but its production process is complicated and it is difficult to effectively combine growth factors and bioactive substances. In recent years, additive manufacturing of NGCs has effectively solved the above problems due to its simple and efficient manufacturing method, and it can be used as the carrier of bioactive substances. This review examines recent advances in additive manufacture of NGCs for PNIs as well as insight into how these approaches could be improved in future studies.

Photobiomodulation in Sciatic Nerve Crush Injuries in Rodents: A Systematic Review of the Literature and Perspectives for Clinical Treatment

Objective : The aim of the study was to perform a literature review to analyze the effect of photobiomodulation in experimental studies on peripheral nerve regeneration after sciatic nerve crush injury in rodents. Methods: A bibliographic search was performed in the electronic databases, including MEDLINE (PubMed), SCOPUS, and SciELO, from 2008 to 2018. Results: A total of 1912 articles were identified in the search, and only 19 fulfilled all the inclusion criteria. Along with the parameters most found in the manuscripts, the most used wavelengths were 660 nm and 830 nm, power of 30 and 40 mW, and energy density of 4 and 10 J/cm² . For total energy throughout the intervention period, the lowest energy found with positive effects was 0.70 J, and the highest 1.141 J. Seventeen studies reported positive effects on nerve regeneration. The variables selected to analyze the effect were: Sciatic Functional Index (SFI), Static Sciatic Index (SSI), morphometric, morphological, histological, zymographic, electrophysiological, resistance mechanics and range of motion (ROM). The variety of parameters used in the studies demonstrated that there is yet no pre-determined protocol for treating peripheral nerve regeneration. Only two studies by different authors used the same power, energy density, beam area, and power density. Conclusion: It was concluded that the therapeutic window of the photobiomodulation presents a high variability of parameters with the wavelength (632.8 to 940 nm), power (5 to 170 mW) and energy density (3 to 280 J /cm² ), promoting nerve regeneration through the expression of cytokines and growth factors that aid in modulating the inflammatory process, improving morphological aspects, restoring the functionality to the animals in a brief period.

Photobiomodulation After Neurotization (Oberlin Procedure) in Brachial Plexus Injury: A Randomized Control Trial

Objective: To investigate effect of photobiomodulation (PBM) on nerve regeneration after neurotization with the Oberlin Procedure (ulnar fascicle to motor branch to biceps) to restore elbow flexion in patients with brachial plexus injury. Materials and methods: This prospective randomized controlled trial was conducted with 14 patients with high brachial plexus injury who underwent neurotization with the Oberlin Procedure to restore elbow flexion. The patients were randomly allocated to two groups of equal numbers: control group and PBM group. In this study, the PBM used has a wavelength of 808 nm, 50 mW power, continuous mode emission, 4 J/cm² dosimetry, administered daily for 10 consecutive days, with an interval of 2 days (weekends). The outcome of surgery was assessed after 1, 2, 3, and 6 months. The nonparametric Mann-Whitney U-test and chi-square test were utilized to compare the results between both groups. Results: After 3 months postoperatively, more patients in the PBM group had demonstrated signs of reinnervation and the mean muscle power was significantly higher in the PBM group. No adverse effects resulted from the administration of PBM. Conclusions: PBM is a treatment modality that can improve nerve regeneration after neurotization with the Oberlin Procedure.

Nerve guide conduits for peripheral nerve injury repair: A review on design, materials and fabrication methods

Peripheral nerves can sustain injuries due to loss of structure and/or function of peripheral nerves because of accident, trauma and other causes, which leads to partial or complete loss of sensory, motor, and autonomic functions and neuropathic pain. Even with the extensive knowledge on the pathophysiology and regeneration mechanisms of peripheral nerve injuries (PNI), reliable treatment methods that ensure full functional recovery are scant. Nerve autografting is the current gold standard for treatment of PNI. Given the limitations of autografts including donor site morbidity and limited supply, alternate treatment methods are being pursued by the researchers. Neural guide conduits (NGCs) are increasingly being considered as a potential alternative to nerve autografts. The anatomy of peripheral nerves, classification of PNI, and current treatment methods are briefly yet succinctly reviewed. A detailed review on the various designs of NGCs, the different materials used for making the NGCs, and the fabrication methods adopted is presented in this work. Much progress had been made in all the aspects of making an NGC, including the design, materials and fabrication techniques. The advent of advanced technologies such as additive manufacturing and 3D bioprinting could be beneficial in easing the production of patient-specific NGCs. NGCs with supporting cells or stem cells, NGCs loaded with neurotropic factors and drugs, and 4D printed NGCs are some of the futuristic areas of interest. STATEMENT OF SIGNIFICANCE: Neural guide conduits (NGCs) are increasingly being considered as a potential alternative to nerve autografts in the treatment of peripheral nerve injuries. A detailed review on the various designs of NGCs, the different materials used for making the NGCs, and the fabrication methods (including Additive Manufacturing) adopted is presented in this work.

Low-level laser therapy for neurosensory recovery after sagittal ramus osteotomy

BACKGROUND

Dento-skeletal deformities are treated combining orthodontic treatment with orthognathic surgery. One of the techniques most used in this type of surgery is the sagittal osteotomy of the mandible. This technique offers many advantages, but within its disadvantages is the inferior alveolar nerve paresthesia. There are various treatments that aim to recovery of the nerve bundle, and one of them is low intensity laser treatment. The aim of this study was to evaluate the effectiveness of low intensity laser therapy in the recovery of neurosensorial tissues after mandibular sagittal osteotomy during orthognathic surgery.

METHODS

Twelve patients submitted to surgery, using mandibular sagittal osteotomy, were treated unilaterally with low intensity infrared (808 nm, GaAIAs active medium) laser, following the inferior alveolar nerve path. The other part of the mandible was treated by placebo. The parameters used were 100 mW of power, irradiancy of 3.6 W/cm2, 2.8J energy per point, an energy density of 100 J/cm2, 28 seconds at each point with a distance of 1.0 cm between points, two sessions per week with a minimum of 10 sessions, starting 48 hours after surgery. Mechanical evaluation was performed in first, fourth, seventh and tenth session.

RESULTS

Significant improvement on the treated side was observed. Comparing the behavior among the variables between the treatment (T) group and the control (C) group in the General Recovery was showed a tendency to better results in the T group when compared to the C group, with statistical difference (P≤0.05) after the 10th laser therapy session.

CONCLUSIONS

The treatment of neurosensorial disorders with infrared low intensity laser could be effective in accelerating recovery, providing greater comfort to the patient, and it presents advantages over other existing methods.

Peripheral nerve injury and myelination: Potential therapeutic strategies

Traumatic peripheral nerve injury represents a major clinical and public health problem that often leads to significant functional impairment and permanent disability. Despite modern diagnostic procedures and advanced microsurgical techniques, functional recovery after peripheral nerve repair is often unsatisfactory. Therefore, there is an unmet need for new therapeutic or adjunctive strategies to promote the functional recovery in nerve injury patients. In contrast to the central nervous system, Schwann cells in the peripheral nervous system play a pivotal role in several aspects of nerve repair such as degeneration, remyelination, and axonal growth. Several non-surgical approaches, including pharmacological, electrical, cell-based, and laser therapies, have been employed to promote myelination and enhance functional recovery after peripheral nerve injury. This review will succinctly discuss the potential therapeutic strategies in the context of myelination following peripheral neurotrauma.

Laser Light Therapy in Inflammatory, Musculoskeletal, and Autoimmune Disease

PURPOSE OF REVIEW

The goal of this review is to summarize the field to date and to discuss strengths and limitations of low-level laser (light) therapy (LLLT) for the future investigation as a treatment of inflammatory disease.

RECENT FINDINGS

LLLT is a promising therapeutic, particularly for those diseases of skin and joints because they are most accessible to treatment. Indeed, the known mechanisms of LLLT support its use for anti-inflammatory purposes, as well as stimulation of tissue growth and repair. Although the standard of care for the majority of inflammatory diseases is immunosuppressive agents such as corticosteroids with undesirable toxicities, LLLT offers a unique approach by being non-invasive and incurring minimal side effects. It is also relatively inexpensive and accessible and even has the possibility to be patient directed at home. There is evidence that LLLT is able to modulate the immune system at the skin and joint, and it has been shown to be efficacious in humans by affecting bacterial colonization as it may pertain to chronic rhinosinusitis. However, there is variability in the methods of laser application as well as a lack of evidence for laser type, dose-ranging studies, and wavelength selection that create barriers to the implementation of LLLT without further more rigorous and standardized study. The heterogeneity makes it difficult to draw strong conclusions about the efficacy of LLLT and its mechanisms.

Efficacy of laser acupuncture for patients with chronic Bell's palsy: A study protocol for a randomized, double-blind, sham-controlled pilot trial

BACKGROUND

Bell's palsy is the most frequent cause of unilateral peripheral facial palsy, a common condition that third of patients can have inadequate recovery and subsequent physical and social impairments. The largely ineffective and even controversial nature of the various medical and surgical treatment options means that novel, alternative approaches are needed. In preclinical and clinical evidence, low-level laser therapy (LLLT) has demonstrated the ability to regenerate peripheral nerves. Laser acupuncture treatment (LAT), the stimulation of traditional acupoints with low-intensity, non-thermal laser irradiation, is a common treatment modality, but its efficacy in chronic Bell's palsy is undetermined. This study aims to evaluate the efficacy of LAT in patients experiencing inadequate recovery from Bell's palsy.

METHODS

This 2-armed, parallel, randomized, subject-assessor-blinded, single-center, sham-controlled pilot trial will randomly assign 32 eligible patients into either a real LAT group (n = 16) or a sham LAT group (n = 16). The real LAT group will receive 3 LAT sessions each week for 6 weeks (a total of 18 sessions), delivered to acupoints corresponding with the affected side of the face. The sham LAT group will receive the same treatment as the real LAT group, but with a sham laser device. The primary outcome measure will be the change from baseline at week 6 in the Facial Disability Index score. Secondary outcomes will monitor changes during treatment in the House-Brackmann and Sunnybrook facial nerve grading systems and stiffness scale, at weeks 1, 3, and 6.

DISCUSSION

To the best of our knowledge, this double-blind, randomized, sham-controlled trial is the first such investigation into the efficacy of LAT in chronic Bell's palsy. Clinical trials using LLLT have shown positive therapeutic effects in acute Bell's palsy, although as yet, the feasibility and efficacy of LAT remain unclear in patients experiencing inadequate recovery from Bell's palsy.

TRIAL REGISTRATION

This trial protocol has been approved by the Research Ethics Committee of the China Medical University Hospital, Taichung, Taiwan (Protocol ID: CMUH107-REC1-030) also registered at ClinicalTrials.gov (identifier no. NCT03592797).

Therapeutic effects of simultaneous Photobiomodulation therapy (PBMT) and Meloxicam administration on experimental acute spinal cord injury: Rat animal model

STUDY DESIGN

Application of Photobiomodulation therapy (PBMT) and meloxicam in acute spinal cord injury, functional recovery and histological evaluation.

OBJECTIVE

Evaluation of the effect of simultaneous PBMT and meloxicam on treatment of acute experimental spinal cord injury and comparing it with the effect of application of each of them separately.

SETTING

The study was conducted at the Department of Surgery & Radiology, Faculty of Veterinary Medicine and Institute of Biomedical Research, University of Tehran, Tehran, Iran.

METHODS

Twenty four rats were used in this study. A compression injury was induced to the T8-T9 segment of the spinal cord of rats using a Fogarty embolectomy catheter. Rats were randomly divided into 4 groups including: Control group, PBMT (810 nm-200 mw-8 s-2 weeks) group, Meloxicam (1 mg/kg) group, and PBMT and Meloxicam (mixed) group. After inducing injury, hind limb performance of the rats was evaluated, using BBB test and then treatment intervention was performed and continued for 2 weeks.

RESULTS

Four  weeks after injury induction, BBB test results were significantly higher in all treatment groups in comparison to control group, however, there were no significant differences among the treatment groups. In addition, histological findings revealed no significant difference between all 4 study groups.

CONCLUSION

According to the results of this study we can conclude that simultaneous and separate application of PBMT and Meloxicam play an effective role in treatment of acute spinal cord injuries.

Photobiomodulation induces antinociception, recovers structural aspects and regulates mitochondrial homeostasis in peripheral nerve of diabetic mice

Diabetic peripheral neuropathy (DPN) is a nervous disorder caused by diabetes mellitus, affecting about 50% of patients in clinical medicine. Chronic pain is one of the major and most unpleasant symptoms developed by those patients, and conventional available treatments for the neuropathy, including the associated pain, are still unsatisfactory and benefit only a small number of patients. Photobiomodulation (PBM) has been gaining clinical acceptance once it is able to promote early nerve regeneration resulting in significant improvement in peripheral nerves disabilities. In this work, the effects of PBM (660 nm, 30 mW, 1.6 J/cm² , 0.28 cm² , 15 s in a continuous frequency) on treating DPN-induced pain and nerve damage were evaluated in an experimental model of diabetic-neuropathy induced by streptozotocin in mice. PBM-induced antinociception in neuropathic-pain mice was dependent on central opioids release. After 21 consecutive applications, PBM increased nerve growth factor levels and induced structural recovery increasing mitochondrial content and regulating Parkin in the sciatic nerve of DPN-mice. Taking together, these data provide new insights into the mechanisms involved in the effects of PBM-therapy emphasizing its therapeutic potential in the treatment of DPN.

Management of an iatrogenic injury to the tibial nerve in a 24-year-old hurdle runner

According to previously published papers, neurovascular injuries seem to be the most unfortunate complications after surgical procedures. In this report, we present our therapeutic approach to iatrogenic injury of the posterior tibial nerve that occurred during ankle arthroscopy in a 24-year-old patient. The outcome of the therapy was a full sensory return and partial motor return (S4 and M3 according to the Medical Research Council Grading System for Nerve Recovery). Our patient was able to resume her typical training. In comparison with available reports, our therapeutic approach enabled earlier functional recovery after nerve injury. While sensory return is beneficial, motor improvement is also important. However, we are conscious of the poor functional outcomes reported by other researchers.

Photobiomodulation in Neuroscience: A Summary of Personal Experience

OBJECTIVE

This review summarizes personal experience with laser photobiomodulation and its potentials for the treatment of peripheral and central nerve system injuries.

METHODS AND RESULTS

Laser photobiomodulation was shown to induce nerve cell activation, have a positive effect on metabolism of the nerve cells, and to stimulate nerve sprouting processes. Studies investigating the effects of laser photobiomodulation on injured peripheral nerves in rats reported immediate protective effects which increase the functional activity of the nerve, decrease or prevent scar tissue formation at the injured site, prevent or decrease degeneration in corresponding motor neurons of the spinal cord, and significantly increase axonal growth and myelinization. A direct application of laser on the spinal cord had a positive impact on the corresponding injured peripheral nerve and promoted recovery. A 780-nm laser phototherapy was applied following peripheral nerve reconstruction using a guiding nerve tube. Results showed myelinated axons crossing through the nerve tube and the continuation of axonal sprouting through the tube toward the distal part of the nerve. In a double-blind, placebo-controlled randomized pilot clinical trial in patients with incomplete stable long-term peripheral nerve injury (PNI), 780-nm laser irradiation progressively improved peripheral nerve function and led to substantial functional recovery. Muscle atrophy represents a major challenge in restorative medicine. Laser phototherapy was shown to increase biochemical activity and improve morphological recovery in muscle and, thus, could have a direct therapeutic application, especially during progressive muscle atrophy resulting from PNI. The effectiveness of composite implants of cultured embryonal nerve cells and the role of laser irradiation on regeneration and repair of the completely transected rat spinal cord were examined. Results suggested that laser photobiomodulation treatment accelerates the axonal growth.

CONCLUSIONS

The significance of the performed experimental and clinical studies is in the provision of new laser technology in field of cell therapy and its therapeutic value for peripheral nerve and spinal cord injuries. Additional well-designed clinical studies are needed to evaluate the effectiveness and role of laser photobiomodulation treatment in a clinical setting.

Beyond the Laboratory, Into the Clinic: What Dogs with Disk Disease Have Taught Us About Photobiomodulation for Spinal Cord Injury

BACKGROUND

For spinal-cord-injured (SCI) patients, integrative medicine approaches such as photomedicine and acupuncture can renew hope and offer previously unrecognized ways to help regain function and improve quality of life.

OBJECTIVE

By understanding the mechanisms of action that these two modalities share, practitioners can better target specific attributes of spinal cord pathophysiology that are limiting recovery. Naturally occurring intervertebral disk disease (IVDD) in dogs affords unparalleled translational opportunities to develop treatment strategies involving photobiomodulation and acupuncture.

CONCLUSIONS

Insights derived through clinical trials of dogs with IVDD have the potential to raise the standard of care for both human and canine SCI patients.

Photobiomodulation Therapy (PBMT) in Peripheral Nerve Regeneration: A Systematic Review

Photobiomodulation therapy (PBMT) has been investigated because of its intimate relationship with tissue recovery processes, such as on peripheral nerve damage. Based on the wide range of benefits that the PBMT has shown and its clinical relevance, the aim of this research was to carry out a systematic review of the last 10 years, ascertaining the influence of the PBMT in the regeneration of injured peripheral nerves. The search was performed in the PubMed/MEDLINE database with the combination of the keywords: low-level laser therapy AND nerve regeneration. Initially, 54 articles were obtained, 26 articles of which were chosen for the study according to the inclusion criteria. In the qualitative aspect, it was observed that PBMT was able to accelerate the process of nerve regeneration, presenting an increase in the number of myelinated fibers and a better lamellar organization of myelin sheath, besides improvement of electrophysiological function, immunoreactivity, high functionality rate, decrease of inflammation, pain, and the facilitation of neural regeneration, release of growth factors, increase of vascular network and collagen. It was concluded that PBMT has beneficial effects on the recovery of nerve lesions, especially when related to a faster regeneration and functional improvement, despite the variety of parameters.

Low level laser therapy alters satellite glial cell expression and reverses nociceptive behavior in rats with neuropathic pain

BACKGROUND

Nerve injury often results in persistent or chronic neuropathic pain characterized by spontaneous burning pain accompanied by allodynia and hyperalgesia. Low level laser therapy (LLLT) is a noninvasive method that has proved to be clinically effective in reducing pain sensitivity and consequently in improving the quality of life. Here we examined the effects of LLLT on pain sensitivity induced by chronic constriction injury (CCI) in rats. CCI was performed on adult male rats, subjected thereafter to 10 sessions of LLLT, every other day, and starting 14 days after CCI. Over the treatment period, the animals were evaluated for nociception using behavioral tests, such as allodynia, thermal and mechanical hyperalgesia. Following the sessions, we observed the involvement of satellite glial cells in the dorsal root ganglion (DRG) using immunoblotting and immunofluorescence approaches. In addition we analyzed the expression levels of interleukin 1 (IL-1β) and fractalkine (FKN) after the same stimulus.

RESULTS

LLLT induced an early reduction (starting at the second session; p ≤ 0.001) of the mechanical and thermal hyperalgesia and allodynia in CCI rats, which persisted until the last session. Regarding cellular changes, we observed a decrease of GFAP (50%; p ≤ 0.001) expression after LLLT in the ipsilateral DRG when compared with the naive group. We also observed a significant increase of pro-inflammatory cytokines after CCI, whereas LLLT dramatically inhibited the overexpression of these proteins.

CONCLUSIONS

These data provide evidence that LLLT reverses CCI-induced behavioral hypersensitivity, reduces glial cell activation in the DRG and decreases pro-inflammatory cytokines; we suggest that this involvement of glial cells can be one potential mechanism in such an effect.

Laser Biophotomodulation in Patients with Neurosensory Disturbance of the Inferior Alveolar Nerve After Sagittal Split Ramus Osteotomy: A 2-Year Follow-Up Study

OBJECTIVE

To evaluate the effect of the application of photobiomodulation in a 2-year follow-up period in patients who have been intervened with a sagittal ramus split osteotomy and present neurosensory disturbance of the inferior alveolar nerve.

BACKGROUND

Photobiomodulation is a common clinical tool in dentistry, for its beneficial effects have been shown in surgical and periodontal wound healing, reducing of swelling and pain, neurosensory recovery, and treatment of temporomandibular joint disorders.

METHODS

This is a 2-year follow-up study with an experimental (Laser) group (n = 33) that received photobiomodulation, and a control (Sham) group (n = 9), placebo. All patients from the Laser group received laser applications (continuous wave of 0.353 W/cm², 27 J in 270 sec per session) on days 1, 2, 3, 5, 10, 14, 21, and 28 after surgery. Neurosensory disturbance was evaluated with five tests: Visual Analog Scale (VAS) for pain and sensitivity, sensitivity threshold test, two-point discrimination, and thermal discrimination. All tests were performed before (24 h before surgery) and after surgery (24 h, 28 days, 60 days, 6 months, 1 year, 2 years, more than 2 years). Participants and evaluator were blinded to intervention. Variables were described with absolute frequencies, percentages, and medians. Ordinal and dichotomous variables were compared with Mann-Whitney's and Fisher's tests, respectively.

RESULTS

Clinical improvement was observed during the follow-up period for the Laser group; general VAS for sensitivity was normal in 11 participants from the Laser group at 2 years postsurgery (40.74%), while no participants from the Sham group achieved this (p = 0.0341). Twenty-three participants recovered initial values for two-point discrimination (69.7%) after 2 years of follow-up (p = 0.0025) as well as sensitivity threshold test. General VAS for pain was normal in 31 patients from the Laser group after 2 years of follow-up (93.94%, p = 0.0254).

CONCLUSIONS

Photobiomodulation was effective for neurosensory recovery on sample studied.

Stimulation Effect of Low Level Laser Therapy on Sciatic Nerve Regeneration in Rat

Introduction: Recent studies showed that low-level laser therapy (LLLT) accelerates the regeneration process of injured peripheral nerve tissue. The objective of this study was investigate the effect of LLLT (780 nm) on regeneration of injured right sciatic nerve of male Wistar rat. Methods: In this research work, the effect of LLLT (780 nm) on the regeneration process and reconstruction of injured peripheral right side sciatic nerve was investigated. Twelve adult male Wistar rats underwent surgery in aseptic conditions under general anesthesia to induce a lesion to their right side sciatic nerve according to standard protocol. Before suturing the location, only the experimental group was treated by laser. The damaged nerve was directly irradiated with (2 J, 100 mW, 40 seconds). The irradiation procedure was terminated in 21 days with little improvement (4 J, 200 mW, 40 seconds) across the skin surface of experimental group. Rats were selected randomly from each group to be sacrificed on different periods and histopathological examination was carried out on the extracted nerves. Results: Significant acceleration of revascularization and angiogenesis of the injury site was observed in the experimental group. Furthermore, a reduction of hemorrhages and increase in blood supply was observed. Also, Wallerian degeneration decreased while higher axonal density compared to the control rats was observed. Moreover, the cross-section analysis of the injured area on the 14th and 21st days as post-surgery showed that the nerve sheath diameter in the lesion area of the experimental group was reduced. While the ratio between thicknesses increased in the control group. Conclusion: The results of the current study suggest that laser phototherapy at 780 nm exactly could accelerate the regeneration process of injured peripheral nerves tissue.

Low-power laser therapy for carpal tunnel syndrome: effective optical power

Low-power laser therapy has been used for the non-surgical treatment of mild to moderate carpal tunnel syndrome, although its efficacy has been a long-standing controversy. The laser parameters in low-power laser therapy are closely related to the laser effect on human tissue. To evaluate the efficacy of low-power laser therapy, laser parameters should be accurately measured and controlled, which has been ignored in previous clinical trials. Here, we report the measurement of the effective optical power of low-power laser therapy for carpal tunnel syndrome. By monitoring the backside reflection and scattering laser power from human skin at the wrist, the effective laser power can be inferred. Using clinical measurements from 30 cases, we found that the effective laser power differed significantly among cases, with the measured laser reflection coefficient ranging from 1.8% to 54%. The reflection coefficient for 36.7% of these 30 cases was in the range of 10-20%, but for 16.7% of cases, it was higher than 40%. Consequently, monitoring the effective optical power during laser irradiation is necessary for the laser therapy of carpal tunnel syndrome.

Low-level laser therapy attenuates the acute inflammatory response induced by muscle traumatic injury

The purpose of this work was to investigate the effect of early and long-term low-level laser therapy (LLLT) on oxidative stress and inflammatory biomarkers after acute-traumatic muscle injury in Wistar rats. Animals were randomly divided into the following four groups: control group (CG), muscle injury group (IG), CG + LLLT, and IG + LLLT: laser treatment with doses of 3 and 5 J/cm(2). Muscle traumatic injury was induced by a single-impact blunt trauma in the rat gastrocnemius. Irradiation for 3 or 5 J/cm(2) was initiated 2, 12, and 24 h after muscle trauma induction, and the treatment was continued for five consecutive days. All the oxidant markers investigated. namely thiobarbituric acid-reactive substance, carbonyl, superoxide dismutase, glutathione peroxidase, and catalase, were increased as soon as 2 h after muscle injury and remained increased up to 24 h. These alterations were prevented by LLLT at a 3 J/cm(2) dose given 2 h after the trauma. Similarly, LLLT prevented the trauma-induced proinflammatory state characterized by IL-6 and IL-10. In parallel, trauma-induced reduction in BDNF and VEGF, vascular remodeling and fiber-proliferating markers, was prevented by laser irradiation. In order to test whether the preventive effect of LLLT was also reflected in muscle functionality, we tested the locomotor activity, by measuring distance traveled and the number of rearings in the open field test. LLLT was effective in recovering the normal locomotion, indicating that the irradiation induced biostimulatory effects that accelerated or resolved the acute inflammatory response as well as the oxidant state elicited by the muscle trauma.

Low Level Laser Therapy: A Panacea for oral maladies

AIM

To review the applications of low level laser therapy on various soft and hard oral tissues. A variety of therapeutic effects of Low Level Laser Therapy have been reported on a broad range of disorders. It has been found amenably practical in dental applications including soft as well as hard tissues of the oral cavity. LLLT has been found to be efficient in acceleration of wound healing, enhanced remodelling and bone repair, regeneration of neural cells following injury, pain attenuation, endorphin release stimulation and modulation of immune system. The aforementioned biological processes induced by Low level lasers have been effectively applied in treating various pathological conditions in the oral cavity. With is article, we attempt to review the possible application of Low Laser Therapy in the field of dentistry.

Long-term effect of pulsed high-intensity laser therapy in the treatment of post-mastectomy pain syndrome: a double blind, placebo-control, randomized study

We assess the long-term effect of pulsed high-intensity laser therapy (HILT) in the treatment of the post-mastectomy pain syndrome (PMPS). A total of 61 women participated in this study (30 in the laser group and 31 in the placebo laser group), with a mean age of 53.56 ± 1.11 years. Patients who were randomly assigned to the laser group received HILT three times per week for 4 weeks, plus a routine physical therapy program (RPTP). The placebo laser group received placebo HILT plus RPTP. The outcomes measured were pain level by visual analog scale (VAS), shoulder range of motion (ROM), and quality of life (QOL). Statistical analysis was performed by ANOVA with repeated measures to compare the differences between baseline and post-treatment measurements and after 12 weeks of follow-up for both groups. The level of statistical significance was set at P < 0.05. Shoulder ROM significantly increased in the laser group after 4 weeks of treatment and after 12 weeks of follow-up compared with the placebo group. VAS results showed a significant decrease post-treatment in the laser group relative to the placebo group, and QOL results showed a significant improvement in the laser group compared with the placebo group and still improved after 12 weeks of follow-up. HILT combined with an RPTP appears to be more effective in patients with PMPS than a placebo laser procedure with RPTP.

Treatment of Bell's Palsy Using Monochromatic Infrared Energy: A Report of 2 Cases

OBJECTIVE

The purpose of the study is to describe the use of monochromatic infrared energy (MIRE) therapy in the management of 2 patients with Bell's palsy.

CLINICAL FEATURES

Two patients presented to a chiropractic clinic with Bell's palsy that was diagnosed by a medical physician. Both patients were treated using MIRE. The acute patient was a 32-year-old male. He presented with left facial palsy 1 day before the consultation. He was unable to puff the left cheek and close the left eyelid. He had difficulty raising the left eyebrow. The chronic case was a 46-year-old lady. Prior to the first consultation, she was treated with corticosteroid and electro-acupuncture for one and a half years, with incomplete recovery. When first seen, the left corner of mouth drooped and she had difficulty raising her left eyebrow.

INTERVENTION AND OUTCOME

Monochromatic infrared energy therapy, emitting 890 nm infrared light, was placed on the post-auricular area, pre-auricular area, the temple and mandibular area of the affected side. Each treatment lasted 30 minutes. Photographs were taken every week to document changes. The acute case received 19 treatments in 6 weeks. He reported an improvement of 95%. The chronic case received a total of 45 treatments in 9 months. She rated an improvement of 50%. At the conclusion of treatment, she was able to close her left eyelid and puff her left cheek but still could not raise her left eyebrow.

CONCLUSION

These 2 patients seemed to respond to a different degree to the MIRE therapy. As 71% of patients with Bell's palsy recover uneventfully without any treatment, the present study describes the course of care but cannot confirm the effectiveness of MIRE therapy in the management of Bell's palsy.

Effect of low-level laser therapy (685 nm, 3 J/cm(2)) on functional recovery of the sciatic nerve in rats following crushing lesion

Previous studies have shown that low-level laser therapy (LLLT) promotes posttraumatic nerve regeneration. The objective of the present study was to assess the efficacy of 685-nm LLLT at the dosage of 3 J/cm(2) in the functional recovery of the sciatic nerve in rats following crushing injury. The left sciatic nerves of 20 male Wistar rats were subjected to controlled crush injury by a hemostatic tweezers, and the rats were randomly allocated into two experimental groups as follows: control group and laser group. Laser irradiation (685 nm wavelength; 15 mW, CW, 3 J/cm(2), spot of 0.028 cm(2)) was started on the postsurgical first day, above the site of injury, and was continued for 21 consecutive days. Functional recovery was evaluated at 3 weeks postoperatively by measuring the sciatic functional index (SFI) and sciatic static index (SSI) at weekly intervals. The treated rats showed improvement in motion pattern. The SFI and SSI results were significant when comparing two groups on the 14th and 21st postoperative days (p < 0.05). There were intra-group differences detected in laser group in different periods (p < 0.05). Low-level laser irradiation, with the parameters used in the present study, accelerated and improved sciatic nerve function in rats after crushing injury.

Restoration and protection of brachial plexus injury: hot topics in the last decade

Brachial plexus injury is frequently induced by injuries, accidents or birth trauma. Upper limb function may be partially or totally lost after injury, or left permanently disabled. With the development of various medical technologies, different types of interventions are used, but their effectiveness is wide ranging. Many repair methods have phasic characteristics, i.e., repairs are done in different phases. This study explored research progress and hot topic methods for protection after brachial plexus injury, by analyzing 1,797 articles concerning the repair of brachial plexus injuries, published between 2004 and 2013 and indexed by the Science Citation Index database. Results revealed that there are many methods used to repair brachial plexus injury, and their effects are varied. Intervention methods include nerve transfer surgery, electrical stimulation, cell transplantation, neurotrophic factor therapy and drug treatment. Therapeutic methods in this field change according to the hot topic of research.

Low-level laser irradiation improves functional recovery and nerve regeneration in sciatic nerve crush rat injury model

The development of noninvasive approaches to facilitate the regeneration of post-traumatic nerve injury is important for clinical rehabilitation. In this study, we investigated the effective dose of noninvasive 808-nm low-level laser therapy (LLLT) on sciatic nerve crush rat injury model. Thirty-six male Sprague Dawley rats were divided into 6 experimental groups: a normal group with or without 808-nm LLLT at 8 J/cm² and a sciatic nerve crush injury group with or without 808-nm LLLT at 3, 8 or 15 J/cm². Rats were given consecutive transcutaneous LLLT at the crush site and sacrificed 20 days after the crush injury. Functional assessments of nerve regeneration were analyzed using the sciatic functional index (SFI) and hindlimb range of motion (ROM). Nerve regeneration was investigated by measuring the myelin sheath thickness of the sciatic nerve using transmission electron microscopy (TEM) and by analyzing the expression of growth-associated protein 43 (GAP43) in sciatic nerve using western blot and immunofluorescence staining. We found that sciatic-injured rats that were irradiated with LLLT at both 3 and 8 J/cm² had significantly improved SFI but that a significant improvement of ROM was only found in rats with LLLT at 8 J/cm². Furthermore, the myelin sheath thickness and GAP43 expression levels were significantly enhanced in sciatic nerve-crushed rats receiving 808-nm LLLT at 3 and 8 J/cm². Taken together, these results suggest that 808-nm LLLT at a low energy density (3 J/cm² and 8 J/cm²) is capable of enhancing sciatic nerve regeneration following a crush injury.

Low-level laser effect in patients with neurosensory impairment of mandibular nerve after sagittal split ramus osteotomy. Randomized clinical trial, controlled by placebo

Objectives: Evaluate the effect on the application of low level laser therapy, in patients that have been previously intervened with a sagittal ramus split osteotomy and present neurosensory impairment due to this surgery, compared with placebo. Study Design: This preliminary study is a randomized clinical trial, with an experimental group (n=17) which received laser light and a control group (n=14), placebo. All participants received laser applications, divided after surgery in days 1, 2, 3, 5, 10, 14, 21 and 28. Neurosensory impairment was evaluated clinically with 5 tests; visual analog scale (VAS) for pain and sensitivity, directional and 2 point discrimination, thermal discrimination, each one of them performed before and after surgery on day 1, and 1, 2 and 6 months. Participants and results evaluator were blinded to intervention. Variables were described with absolute frequencies, percentages and medians. Ordinal and dichotomous variables were compared with Mann Whitney’s and Fisher’s test respectively. Results: Results demonstrate clinical improvement in time, as well as in magnitude of neurosensory return for laser group; VAS for sensitivity reached 5 (normal), 10 participants recovered initial values for 2 point discrimination (62,5%) and 87,5% recovered directional discrimination at 6 months after surgery. General VAS for sensitivity showed 68,75% for laser group, compared with placebo 21,43% (p-value = (0.0095). Left side sensitivity (VAS) showed 3.25 and 4 medians for placebo and laser at 2 months, respectively (p-value = (0.004). Conclusions: Low-level laser therapy was beneficial for this group of patients on recovery of neurosensory impairment of mandibular nerve, compared to a placebo.

Key words:Laser Therapy, low-level, LLLP, osteotomy, sagittal split ramus, paresthesia, mandibular nerve.

[Nerve injuries and posttraumatic therapy]

Peripheral nerve injuries are a common clinical problem and can represent a major challenge, especially after trauma. In order to achieve optimal therapy, an early and adequate diagnosis with subsequent therapy is critical for functional preservation and restoration. Especially after complete severance of a peripheral nerve, the surgical techniques for nerve coaptation are an important prerequisite for peripheral nerve regeneration. The importance and necessity of adequate nerve coaptation and nerve transplantation are presented in detail. In addition, the types of primary and secondary nerve reconstruction procedures are described as well as the optimal time point of nerve repair. This article provides a comprehensive overview of the possibilities for diagnosis and intervention after nerve injury, additionally including an algorithm for surgical intervention. Furthermore, possible pitfalls and factors for improving the functional outcome are presented to optimize results with trauma-related nerve injury.

The use of phototherapy in peripheral nerve regeneration: an updated critical review

This review describes the possible factors that may have contributed to the variability of the results between studies that have assessed the effects of phototherapy on peripheral nerve regeneration. Furthermore, it aims to make recommendations to overcome the methodological shortcomings identified. A search of the literature was conducted. In vitro and in vivo experimental studies and clinical trials were included. Twenty five studies were critically reviewed and showed considerable variability in irradiation parameters, techniques, approaches, length of irradiation courses, experimental injury tools and procedures. Many studies that have investigated the use of phototherapy in nerve regeneration produce positive results. However, the majority of these studies suffered from a number of shortcomings: no evidence of blinding and/or randomizing procedures, lack of specification of irradiation parameters, unspecified and/or inadequate tests in their experimental injury procedures, inappropriate irradiation parameters and/or poor experimental conditions.

Effect of low level laser therapy on chronic compression of the dorsal root ganglion

Dorsal root ganglia (DRG) are vulnerable to physical injury of the intervertebral foramen, and chronic compression of the DRG (CCD) an result in nerve root damage with persistent morbidity. The purpose of this study was to evaluate the effects of low level laser therapy (LLLT) on the DRG in a CCD model and to determine the mechanisms underlying these effects. CCD rats had L-shaped stainless-steel rods inserted into the fourth and fifth lumbar intervertebral foramen, and the rats were then subjected to 0 or 8 J/cm2 LLLT for 8 consecutive days following CCD surgery. Pain and heat stimuli were applied to test for hyperalgesia following CCD. The levels of TNF-α, IL-1β and growth-associated protein-43 (GAP-43) messenger RNA (mRNA) expression were measured via real-time PCR, and protein expression levels were analyzed through immunohistochemical analyses. Our data indicate that LLLT significantly decreased the tolerable sensitivity to pain and heat stimuli in the CCD groups. The expression levels of the pro-inflammatory cytokines TNF-α and IL-1β were increased following CCD, and we found that these increases could be reduced by the application of LLLT. Furthermore, the expression of GAP-43 was enhanced by LLLT. In conclusion, LLLT was able to enhance neural regeneration in rats following CCD and improve rat ambulatory behavior. The therapeutic effects of LLLT on the DRG during CCD may be exerted through suppression of the inflammatory response and induction of neuronal repair genes. These results suggest potential clinical applications for LLLT in the treatment of compression-induced neuronal disorders.

Lack of effectiveness of laser therapy applied to the nerve course and the correspondent medullary roots

OBJECTIVE:

To investigate the influence of low intensity laser irradiation on the regeneration of the fibular nerve of rats after crush injury.

METHODS:

Twenty-five rats were used, divided into three groups: 1) intact nerve, no treatment; 2) crushed nerve, no treatment; 3) crush injury, laser irradiation applied on the medullary region corresponding to the roots of the sciatic nerve and subsequently on the course of the damaged nerve. Laser irradiation was carried out for 14 consecutive days.

RESULTS:

Animals were evaluated by functional gait analysis with the peroneal functional index and by histomorphometric analysis using the total number of myelinated nerve fibers and their density, total number of Schwann cells, total number of blood vessels and the occupied area, minimum diameter of the fiber diameter and G-quotient.

CONCLUSION:

According to the statistical analysis there was no significant difference among groups and the authors conclude that low intensity laser irradiation has little or no influence on nerve regeneration and functional recovery. Laboratory investigation.