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THOR on YouTubeThis our biggest bimonthly Literature Watch ever. There is so much interesting clinical and lab work being published including LLLT treatment of Meniere’s Disease, muscle fatigue, stroke, bone healing, Oral Mucositis, TMJ, Carpal Tunnel Syndrome, TB, burns and even Snake Venom.
Effect of Low-Level Laser Therapy on Mast Cells in Viability of the Transverse Rectus Abdominis Musculocutaneous Flap.
Pinfildi CE, Liebano RE, Hochman BS, Enokihara MM, Lippert R, Gobbato RC, Ferreira LM
Department of Plastic Surgery and Professor of IMES-FAFICA, Sao Paulo Federal University (UNIFESP), Sao Paulo, SP, Brazil.
Abstract Objective: To assess the effect of low-level laser therapy (LLLT) on viability of mast cells of the transverse rectus abdominis musculocutaneous (TRAM) flap. Background Data: LLLT has been recently used on the TRAM flap to stimulate mast cells. Materials and Methods: Eighty-four Wistar rats were randomly divided into seven groups of 12 rats in each: group 1 (sham laser therapy); group 2 received 3 J/cm(2) at one point; group 3 received 3 J/cm(2) at 24 points; group 4 received 72 J/cm(2) at 1 point; group 5 received 6 J/cm(2) at 1 point; group 6 received 6 J/cm(2) at 24 points; and group 7 received 144 J/cm(2) at 1 point. All experimental groups underwent LLLT immediately after TRAM surgery and on the next two following days, for three sessions in total. The percentage of the area of skin flap necrosis was calculated on the fourth postoperative day and two samples of skin were collected from each rat with a 1-cm(2) punch to perform mast cell evaluations with toluidine blue dye. Results: Statistically significant differences were found in the percentage of necrosis, and higher values were seen in group 1 than in all other groups. Among groups 3-7 no statistically significant differences were found (p < 0.292). For mast cells, when group 1 was compared to groups 5 (6 J/cm(2) at 1 point) and 7 (144 J/cm(2) at 1 point), it had fewer mast cells. Conclusion: LLLT at a wavelength of 670 nm was effective at reducing the necrotic area, and we found that it can stimulate mast cells growth to increase vascular perfusion.
Photomed Laser Surg 2008 Sep 11
Histologic study of the effect of laser therapy on bone repair.
Blaya DS, Guimaraes MB, Pozza DH, Weber JB, de Oliveira MG
AIM: This study used histologic analysis and HE staining to evaluate laser biomodulation of bone repair in cavities made in the femurs of rats that underwent non-ablative laser irradiation. METHODS AND MATERIALS: Eighteen male Wistar rats weighing 300 to 400 grams were randomly assigned to three groups of six animals each. A surgical defect site was produced with a trephine about 2 mm in diameter under abundant irrigation. In Group I the complete surgical protocol to produce a bone defect was followed but without laser radiation (control). In Group II a continuous wave 830 nm infrared laser was used at 10 J/cm2 and 50 mW at each point of the surgical site. In Group III a continuous wave 685 nm infrared laser at 10J/cm2 and 35 mW was used at each point of surgical site. The animals were irradiated at intervals of 48 hours beginning immediately after the preparation of the defect and were sacrificed on the 15th, 21st, and 30th days. Slides were studied by means of descriptive analysis. RESULTS: Greater degrees of new bone formation and vertical regeneration were found in the irradiated groups than in the control group. CONCLUSION: Laser therapy in this study protocol was efficient in promoting bone repair. CLINICAL SIGNIFICANCE: The use of laser technology has been used to improve the clinical results of bone surgeries and to promote a more comfortable postoperative period and quicker healing.
J Contemp Dent Pract 2008 9(6) 41-8
Efficacy of low-level laser therapy in the treatment of temporomandibular disorder.
da Cunha LA, Firoozmand LM, da Silva AP, Esteves SA, Oliveira W
Benjamim Manoel Amarante, Sao Jose dos campos, SP, Brazil. liaalves@hotmail.com
AIMS: To evaluate the effectiveness of low-level laser therapy (LLLT) in patients presenting with temporomandibular disorder (TMD) in a random and placebo-controlled research design. METHODS: The sample consisted of 40 patients, divided into an experimental group (G1) and a placebo group (G2). The treatment was done with an infrared laser (830nm, 500mW, 20s, 4J/point) at the painful points, once a week for four consecutive weeks. The patients were evaluated before and after the treatment through a Visual Analogue Scale (VAS) and the Craniomandibular Index (CMI). RESULTS: The baseline and posttherapy values of VAS and CMI were compared by the paired T-test, separately for the placebo and laser groups. A significant difference was observed between initial and final values (p < 0.05) in both groups. Baseline and post-therapy values of pain and CMI were compared in the therapy groups by the two-sample T-test, yet no significant differences were observed regarding VAS and CMI (p > 0.05). CONCLUSION: After either placebo or laser therapy, pain and temporomandibular symptoms were significantly lower, although there was no significant difference between groups. The low-level laser therapy was not effective in the treatment of TMD, when compared to the placebo.
Int Dent J 2008 Aug 58(4) 213-7
Evaluation of low-level laser therapy of osteoblastic cells.
Pires Oliveira DA, de Oliveira RF, Zangaro RA, Soares CP
Laboratorio de Dinamica de Compartimentos Celulares, Instituto de Pesquisa e Desenvolvimento, UNIVAP, Sao Jose dos Campos, Sao Paulo, Brazil.
OBJECTIVE: The purpose of the present study was to evaluate the effect of biomodulation on osteoblastic cells using a gallium-aluminium-arsenide diode laser. BACKGROUND DATA: Low-level laser therapy (LLLT) is a non-pharmacological therapeutic resource to which biological tissues respond well, producing such effects as the acceleration of bone formation and bone repair. MATERIALS AND METHODS: Osteoblastic cell cultures (OFCOL II) were irradiated with a gallium-aluminium-arsenide diode laser (GaAlAs lambda = 830 nm; 50 mW; 3 J/cm(2); 600-microm-diameter optical fiber) and divided into two groups: group 1–irradiated cells, and group 2–non-irradiated cells. Irradiation occurred at 24-h intervals for a total of 3 d. After each interval, the cells were marked with Mito Tracker Orange dye to assess the biostimulatory effect on mitochondrial activity and cell proliferation using an MTT assay. RESULTS: Intense grouping of mitochondria in the perinuclear region was observed at 24 h and 48 h following irradiation. Changes from a filamentous to a granular appearance in mitochondrial morphology and mitochondria distributed throughout the cytoplasm were observed 72 h following proliferation. Such changes led to an in vitro proliferation process, as confirmed by the MTT assay. CONCLUSION: LLLT has shown itself capable of altering mitochondrial activity and the population of OFCOL II cells.
Photomed Laser Surg 2008 Aug 26(4) 401-4
The effects of low level laser in clinical outcome and neurophysiological results of carpal tunnel syndrome.
Shooshtari SM, Badiee V, Taghizadeh SH, Nematollahi AH, Amanollahi AH, Grami MT
Shiraz University of medical science, Shiraz, Iran
OBJECTIVES: Carpal tunnel syndrome (CTS) is the most common neuropathy that can be diagnosed with confidence by the nerve conduction study (NCS). One of the recent treatments of CTS is the application of low power laser (LPL) therapy. The present study evaluates the effects of LPL irradiation through NCS and clinical signs and symptoms. METHODS: A total of 80 patients were included in this study. Diagnosis of CTS was based on both clinical examination and electromyographic (EMG) findings. Patients were randomly assigned into two groups. Test group (group A) underwent laser therapy (9-11 joules/cm2) over the carpal tunnel area. Control group (group B) received sham laser therapy. Pain, hand grip strength, median proximal sensory and motor latencies, transcarpal median sensory nerve conduction (SNCV) were recorded. After fifteen sessions of irradiation (five times per week), parameters were recorded again and clinical symptoms were measured in both groups. Pain was evaluated by Visual Analog Scale (VAS; day-night). Hand grip was measured by Jamar dynometer. Paired t-test and independent sample t-test were used for statistical analysis. RESULTS: There was a significant improvement in clinical symptoms and hand grip in group A (p < 0.001). Proximal median sensory latency, distal median motor latency and median sensory latencies were significantly decreased (p < 0.001). Transcarpal median SNCV increased significantly after laser irradiation (p < 0.001). There were no significant changes in group B except changes in clinical symptoms (p < 0.001). CONCLUSIONS: Laser therapy as a new conservative treatment is effective in treating CTS paresthesia and numbness and improves the subjects’ power of hand grip and electrophysiological parameters.
Electromyogr Clin Neurophysiol 2008 Jun-Jul 48(5) 229-31
[Low-energy semiconductor laser intranasal irradiation of the blood improves blood coagulation status in normal pregnancy at term.]
Gao X, Zhi PK, Wu XJ
Department of Obstetrics and Gynecology, Tung Wah Hospital Affiliated to Sun Yat-sen University, Dongguang 523110, China. E-mail: flyhighlucky@gmail.com.
OBJECTIVE: To explore the effect of low-energy semiconductor laser intranasal irradiation of the blood on blood coagulation status in healthy pregnant women at term. METHODS: Low-energy semiconductor laser was introduced into the nasal cavity in 126 healthy pregnant women at term and 123 healthy young unmarried women as the control group. The plasma prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time (TT), and fibrinogen levels were examined using transmissive turbidimetry after the therapy. RESULTS: PT, APTT and TT levels were significantly lowered, whereas fibrinogen level significantly increased in the healthy pregnant women before the laser therapy as compared with those in the control group (P<0.01). After intranasal laser therapy, these parameters were significantly improved in the healthy pregnant women (P<0.05) although there were differences from those of the control group. CONCLUSION: Low-energy semiconductor laser intranasal irradiation of the blood can effectively improve high blood coagulation status in healthy pregnant women at term.
Nan Fang Yi Ke Da Xue Xue Bao 2008 Aug 28(8) 1400-1
Attenuation of TCDD-induced oxidative stress by 670 nm photobiomodulation in developmental chicken kidney.
Lim J, Sanders RA, Yeager RL, Millsap DS, Watkins JB 3rd, Eells JT, Henshel DS
School of Public and Environmental Affairs, Indiana University, Bloomington, IN 47405, USA.
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), a potent developmental teratogen inducing oxidative stress and sublethal changes in multiple organs, provokes developmental renal injuries. In this study, we investigated TCDD-induced biochemical changes and the therapeutic efficacy of photobiomodulation (670 nm; 4 J/cm(2)) on oxidative stress in chicken kidneys during development. Eggs were injected once prior to incubation with TCDD (2 pg/g or 200 pg/g) or sunflower oil vehicle control. Half of the eggs in each dose group were then treated with red light once per day through embryonic day 20 (E20). Upon hatching at E21, the kidneys were collected and assayed for glutathione peroxidase, glutathione reductase, catalase, superoxide dimutase, and glutathione-S-transferase activities, as well as reduced glutathione and ATP levels, and lipid peroxidation. TCDD exposure alone suppressed the activity of the antioxidant enzymes, increased lipid peroxidation, and depleted available ATP. The biochemical indicators of oxidative and energy stress in the kidney were reversed by daily phototherapy, restoring ATP and glutathione contents and increasing antioxidant enzyme activities to control levels. Photobiomodulation also normalized the level of lipid peroxidation increased by TCDD exposure. The results of this study suggest that 670 nm photobiomodulation may be useful as a noninvasive treatment for renal injury resulting from chemically induced cellular oxidative and energy stress.
J Biochem Mol Toxicol 2008 Jul 22(4) 230-9
A possible mechanism for visible light-induced wound healing.
Lipovsky A, Nitzan Y, Lubart R
The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel.
BACKGROUND AND OBJECTIVES: Chronic wounds resistant to conventional therapy have been treated successfully with low energy lasers and light emitting diodes (LEDs) in the visible and near IR region. It has been proposed that production of low level reactive oxygen species (ROS) following illumination is the first step of photobiomodulation. It was also shown that white light (400-800 nm) has similar stimulatory effects as lasers and LEDs. ROS at higher levels are toxic to cells and bacteria. STUDY DESIGN/MATERIALS AND METHODS: In the present study, we examined the phototoxicity of broadband (400-800 nm, 120 J/cm(2)) visible light on the survival of several pathogenic bacteria: Staphylococcus aureus 195, Pseudomonas aeruginosa 1316, Escherichia coli 1313, and Serratia marcescens. These bacteria were chosen due to their high prevalence in infected wounds. The survival of bacterial cells following illumination was monitored by counting the number of colony forming units before and after exposure to light. RESULTS: Illumination with white light, 120 J/cm(2), caused a reduction of 62%, 83%, and 56% in the colony count of E. coli 1313, S. aureus 195 and S. marcescens, respectively, though no reduction in the viability of P. aeruginosa 1316 was demonstrated. The phototoxic effect was found to involve induction of ROS production by the bacteria. It was also found that illumination of S. aureus 195 and E. coli 1313 in the presence of pyocyanin, known to be secreted by P. aeruginosa, had a stronger bactericidal effect compared to illumination alone. CONCLUSION: Visible light at high intensity can kill bacteria in infected wounds. Thus, illumination of infected wounds with intense visible light, prior to low intensity illumination for stimulating wound closure, may reduce infection and promote healing.
Lasers Surg Med 2008 Sep 40(7) 509-14
Anti-Inflammatory effects of low-level laser therapy (660 nm) in the early phase in carrageenan-induced pleurisy in rat.
Boschi ES, Leite CE, Saciura VC, Caberlon E, Lunardelli A, Bitencourt S, Melo DA, Oliveira JR
Laboratorio de Pesquisa em Biofisica Celular e Inflamacao, Pontificia Universidade Catolica do Rio Grande do Sul (PUCRS), Av. Ipiranga 6681 predio 12C sala 263, CEP 90619-900 Porto Alegre, RS, Brazil.
BACKGROUND AND OBJECTIVE: In the classic model of pleurisy there is little evidence about the anti-inflammatory effects of low-level laser therapy (LLLT) as well the dosage characteristics, such as wavelength, total energy, number and pattern of treatment. In this study we investigated the potential effects of LLLT on modulating the pro-inflammatory and anti-inflammatory mediators of acute inflammation in a rat pleurisy model. STUDY DESIGN/MATERIALS AND METHODS: A sample of 48 female Wistar rats were divided into control and experiential groups. An inflammation was induced by carrageenan (0.2 ml) injected into the pleural cavity. At 1, 2, and 3 hours after induction a continuous wave (20 mW) diode laser of the InGaAlP (660 nm) type was used in the four laser groups with different doses and treatment patterns. One group received a single dose of 2.1 J and the other three groups received a total energy of 0.9, 2.1, and 4.2 J. Four hours later the exudate volume, total and differential leukocytes, protein concentration, NO, IL-6, IL-10, TNF-alpha, and MCP-1 were measured from the aspirated liquid. RESULTS: All the treatment patterns and quantity of energy studied show significant reduction of the exudate volume (P<0.05). Using energy of 0.9 J only NO, IL-6, MCP-1 and IL-10 are significantly reduced (P<0.05). On the other hand, higher energies (2.1 and 4.2 J) significantly reduce all variables independently of the treatment pattern. The neutrophil migration has a straight correlation with the TNF-alpha (r = 0.551) and NO (r = 0.549) concentration. CONCLUSIONS: LLLT-660 nm induced an anti-inflammatory effect characterized by inhibition of either total or differential leukocyte influx, exudation, total protein, NO, IL-6, MCP-1, IL-10, and TNF-alpha, in a dose-dependent manner. Under these conditions, laser treatment with 2.1 J was more effective than 0.9 and 4.2 J.
Lasers Surg Med 2008 Sep 40(7) 500-8
[Laser Doppler fluometry in assessment of endothelium state in patients with coronary heart disease and its correction by intravenous laser irradiation of blood]
Influence of laser therapy on vascular endothelium function in patients with stable angina pectoris, detected by the method of laser Doppler fluorimetry, was studied. 77patients with stable angina pectoris were divided into 2 groups. In control group only medicamentous therapy was used, in main group a course of intravenous blood laser irradiation was carried out additionally. The increase of initially decreased mean index of microcirculation and index of microcirculation after acetylcholine iontophoresis was noticed. Tendency to increase of endothelial oscillations and capillary blood flow under influence of intravenous blood laser irradiation was noticed too. Laser therapy can be considered an effective method of increase of endothelial functional activity in patients with stable angina pectoris.
Klin Med (Mosk) 2008 86(6) 44-7
Effect of equal daily doses achieved by different power densities of low-level laser therapy at 635 nm on open skin wound healing in normal and corticosteroid-treated rats.
Gal P, Mokry M, Vidinsky B, Kilik R, Depta F, Harakalova M, Longauer F, Mozes S, Sabo J
Department of Medical Biophysics, Pavol Jozef Safarik University, Trieda SNP 1, 040 11, Kosice, Slovak Republic, galovci@yahoo.com.
Optimal parameters of low-level laser therapy (LLLT) for wound healing are still discussed. Hence, our study was aimed to compare effects of different power densities of LLLT at 635 nm in rats. Four, round, full-thickness, skin wounds were made on the backs of 48 rats that were divided into two groups (non-steroid laser-treated and steroid laser-treated). Three wounds were stimulated daily with a diode laser (daily dose 5 J/cm(2)) each with different power density (1 mW/cm(2), 5 mW/cm(2), and 15 mW/cm(2)), whereas the fourth wound served as a control. Two days, 6 days, and 14 days after surgery, eight animals from each group were killed and samples were removed for histological evaluation. In the non-steroid laser-treated rats, significant acceleration of epithelization and collagen synthesis 2 days and 6 days after surgery was observed in stimulated wounds. In steroid laser-treated rats, 2 days and 14 days after surgery, a decreased leucocyte/macrophage ratio and a reduction in the area of granulation tissue were recorded, respectively. In conclusion, LLLT, by the method we used, improved wound healing in the non-steroid laser-treated rats, but it was useless after corticosteroid treatment.
Lasers Med Sci 2008 Aug 21
Pre-Irradiation of blood by gallium aluminum arsenide (830 nm) low-level laser enhances peripheral endogenous opioid analgesia in rats.
Hagiwara S, Iwasaka H, Hasegawa A, Noguchi T
Department of Brain and Nerve Science, Anesthesiology, Oita University Faculty of Medicine, 1-1 Idaigaoka-Hasamamachi-Yufu City-Oita 879-5593, Japan. saku@med.oita-u.ac.jp
BACKGROUND: Low-level laser therapy (LLLT) has been reported to relieve pain, free of side effects. However, the mechanisms underlying LLLT are not well understood. Recent studies have also demonstrated that opioid-containing immune cells migrate to inflamed sites and release beta-endorphins to inhibit pain as a mode of peripheral endogenous opioid analgesia. We investigated whether pre-irradiation of blood by LLLT enhances peripheral endogenous opioid analgesia. METHODS: The effect of LLLT pretreatment of blood on peripheral endogenous opioid analgesia was evaluated in a rat model of inflammation. Additionally, the effect of LLLT on opioid production was also investigated in vitro in rat blood cells. The expression of the beta-endorphin precursors, proopiomelanocortin and corticotrophin releasing factor, were investigated by reverse transcription polymerase chain reaction. RESULTS: LLLT pretreatment produced an analgesic effect in inflamed peripheral tissue, which was transiently antagonized by naloxone. Correspondingly, beta-endorphin precursor mRNA expression increased with LLLT, both in vivo and in vitro. CONCLUSION: These findings suggest that that LLLT pretreatment of blood induces analgesia in rats by enhancing peripheral endogenous opioid production, in addition to previously reported mechanisms.
Anesth Analg 2008 Sep 107(3) 1058-63
Increased expression of heat shock protein 70 and heat shock factor 1 in chronic dermal ulcer tissues treated with laser-aided therapy.
Zhou JD, Luo CQ, Xie HQ, Nie XM, Zhao YZ, Wang SH, Xu Y, Pokharel PB, Xu D
Department of Burns and Plastic Surgery, Third Xiangya Hospital, Central South University, Changsha, Hunan 410013, China. zjianda@yahoo.com.cn)
BACKGROUND: Chronic dermal ulcers are also referred to as refractory ulcers. This study was conducted to elucidate the therapeutic effect of laser on chronic dermal ulcers and the induced expression of heat shock factor 1 (HSF1) and heat shock protein 70 (HSP70) in wound tissues. METHODS: Sixty patients with 84 chronic dermal ulcers were randomly divided into traditional therapy and laser therapy groups. Laser treatment was performed in addition to traditional therapy in the laser therapy group. The treatment efficacy was evaluated after three weeks. Five tissue sections of healing wounds were randomly collected along with five normal skin sections as controls. HSP70-positive cells from HSP70 immunohistochemical staining were counted and the gray scale of positive cells was measured for statistical analysis. Reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting were performed to determine the mRNA and protein expressions of HSF1 and HSP70. RESULTS: The cure rate of the wounds and the total efficacy in the laser therapy group were significantly higher than those in the traditional therapy group (P < 0.05, P < 0.01, respectively). Immunohistochemical staining revealed that the HSP70-positive cell count was significantly higher in laser therapy group than those in the traditional therapy group and controls (P < 0.01), and the gray scale of the cell signal was obviously lower than traditional therapy group and controls (P < 0.05). By contrast, the traditional therapy group and the control group were not significantly different. The RNA levels of HSF1 and HSP70 were higher in the laser therapy group by RT-PCR, but very low in normal skin and the traditional therapy group. The analysis on the gray scale of the Western blot bands indicated that the expression of HSF1 and HSP70 in the laser therapy group was significantly higher than in the traditional therapy group and the control group (P < 0.01), and the expression in the traditional therapy group was also higher than in the control group (P < 0.05). CONCLUSION: Laser-aided therapy of chronic dermal ulcers plays a facilitating role in healing due to the mechanism of laser-activated endogenous heat shock protection in cells in wound surfaces.
Chin Med J (Engl) 2008 Jul 20 121(14) 1269-73
[Primary drug resistance of Mycobacterium tuberculosis in adolescents with tuberculosis: the specific features of its clinical course, the efficiency of treatment]
Ninety adolescents suffering from tuberculosis with primary drug resistance (PDR) in Mycobacterium tuberculosis (MBT) were followed up. All the patients had active, marked processes, mainly infiltrative tuberculosis in the phase of decay and dissemination. MBT resistance to 3 drugs or more was detected in most patients (62.3%). Multidrug resistance was 32.2%. The course of the disease was chiefly favorable. An exacerbation of the process occurred during therapy in 6.6% of patients. In patients with PDR, abacillation occurred in 100% of cases and the decay cavities closed in 86.6% by the end of the course of therapy. The PDR patients received treatment with both first- and second-line drugs, had surgery, collapsotherapy, laser therapy, and physiotherapeutic treatments, and lidase. Treatment of patients with drug-resistant tuberculosis presents severe difficulties. However, good results can be achieved in most patients, by applying an individual approach to each patient and determining the optimum chemotherapy regimens and pathogenetic treatments.
Probl Tuberk Bolezn Legk 2008 (5) 17-20
[Laser therapy in complex treatment for early tuberculosis of peripheral lymph nodes]
The high efficiency of etiopathogenetic treatment was established in patients with the proliferative form of isolated tuberculosis of peripheral lymph nodes, by using a combination of antituberculosis chemotherapy and low-energy laser radiation without surgical intervention. At the same time after 2.5-3-months, there was a persistent improvement, suggested by the elimination of clinical and laboratory signs of tuberculosis intoxication, disappearance of enlarged lymph nodes and a tendency of the body’s tuberculosis sensitivity to reduce, evidenced by Mantoux 2 TE PPD-L test. The paper shows it efficient to pursue medical treatment policy in early isolated tuberculosis of peripheral lymph nodes.
Probl Tuberk Bolezn Legk 2008 (6) 15-8
Visible Lasers Were Better Than Invisible Lasers in Accelerating Burn Healing on Diabetic Rats.
Al-Watban FA, Zhang XY, Andres BL, Al-Anize A
Laser Research Section, Biological and Medical Research Department, King Faisal Specialist Hospital and Research Centre, Riyadh, Kingdom of Saudi Arabia.
Abstract Objective: This study was designed to compare the efficacy of low-power visible with invisible lasers for accelerating burn healing on diabetic rats. Background Data: Low-level laser therapy (LLLT) has been used in a number of diabetic animal and human studies, with some researchers finding positive and others finding no effects. Materials and Methods: Male Sprague-Dawley rats were used in this study. Streptozocin (70 mg/kg) was injected to induce diabetes. A burn was created using a metal rod heated to 600 degrees C applied to the shaved back of the animals. The study was performed using 532-, 633-, 670-, 810-, and 980-nm diode lasers. Doses of 5, 10, 20, and 30 J/cm(2) and a treatment schedule of three sessions per week were used in the experiments. The burned area on all rats was measured and plotted on a slope chart. The slope values (mm(2)/d) and the percentage of the healed burns were computed. Results: The percentage of healed burn areas on the rats after LLLT was 78.37% for the visible lasers and 50.68% for the invisible lasers. There were significant differences (p < 0.005) in the percentage of healed burn areas after laser therapy between the visible and the invisible lasers. Conclusion: Low-power laser therapy using visible and invisible lasers with the appropriate treatment parameters can accelerate burn healing on diabetic rats. The effects of visible lasers were more pronounced than those of invisible lasers in accelerating burn healing on diabetic rats.
Photomed Laser Surg 2008 Aug 15
Laser therapy in acute stroke treatment.
Yip S, Zivin J
Department of Neuroscience, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0624, USA.
Recent development of near infrared light therapy (NILT) as an acute stroke treatment is promising. In various preclinical animal stroke models, NILT has been shown to be effective in improving long-term stroke outcome. More importantly, NILT has a long postischemic therapeutic window that has not been previously observed in other treatment modalities. The preliminary efficacy and safety of NILT in acute stroke patients were demonstrated in the recently published phase II NeuroThera Effectiveness and Safety Trial (NEST-1). If confirmed by the NEST-II trial, NILT will revolutionize acute stroke management as ut has a long time window (possible 24 hr) for therapy. Moreover, understanding the mechanisms of action of NILT will provide a new therapeutic target for future drug or device development.
Int J Stroke 2008 May 3(2) 88-91
Severity of Oral Mucositis in Patients Undergoing Hematopoietic Cell Transplantation and an Oral Laser Phototherapy Protocol: A Survey of 30 Patients.
Eduardo FD, Bezinelli L, Luiz AC, Correa L, Vogel C, Eduardo CD
Hospital Israelita Albert Einstein, Unit of Bone Marrow Transplantation, School of Dentistry, University of Sao Paulo, Sao Paulo, Brazil.
Abstract Background Data and Objective: Oral mucositis (OM) is one of the worst cytotoxic effects of chemotherapy and radiotherapy in patients undergoing hematopoietic cell transplantation (HCT), and it causes severe morbidity. Laser phototherapy has been considered as an alternative therapy for prevention and treatment of OM. The aim of this study was to describe the incidence and severity of OM in HCT patients subjected to laser phototherapy, and to discuss its effect on the oral mucosa. Patients and Methods: Information concerning patient age and gender, type of basic disease, conditioning regimen, type of transplant, absence or presence of pain related to the oral cavity, OM grade, and adverse reactions or unusual events were collected from 30 patients undergoing HCT (allogeneic or autologous). These patients were given oral laser phototherapy with a InGaAIP laser (660 nm and 40 mW) daily. The data were tabulated and their frequency expressed as percentages. Results: In the analysis of those with OM, it was observed that 33.4% exhibited grade I, 40% grade II, 23.3% grade III, and 3.3% grade IV disease. On the most critical post-HCT days (D+5 and D+8), it was observed that 63.3% of patients had grade I and 33.3% had grade II disease; no patients had grade III or IV disease in this period. This severity of OM was similar to that seen in other studies of laser phototherapy and OM. Conclusion: The low grades of OM observed in this survey show the beneficial effects of laser phototherapy, but randomized clinical trials are necessary to confirm these findings.
Photomed Laser Surg 2008 Aug 12
Safety Profile of Transcranial Near-Infrared Laser Therapy Administered in Combination With Thrombolytic Therapy to Embolized Rabbits.
Lapchak PA, Han MK, Salgado KF, Streeter J, Zivin JA
From the Department of Neuroscience, University of California San Diego, La Jolla, Calif; the Veterans Administration San Diego Healthcare System, Stroke Research, San Diego, Calif; the Veterans Medical Research Foundation, San Diego, Calif; and Photothera Inc, Carlsbad, Calif.
BACKGROUND AND PURPOSE: Transcranial near-infrared laser therapy (TLT) is currently under investigation in a pivotal clinical trial that excludes thrombolytic therapy. To determine if combining tissue plasminogen activator (tPA; Alteplase) and TLT is safe, this study assessed the safety profile of TLT administered alone and in combination with Alteplase. The purpose for this study is to determine if the combination of TLT and thrombolysis should be investigated further in a human clinical trial. METHODS: We determined whether postembolization treatment with TLT in the absence or presence of tPA would affect measures of hemorrhage or survival after large clot embolism-induced strokes in New Zealand white rabbits. RESULTS: TLT did not significantly alter hemorrhage incidence after embolization, but there was a trend for a modest reduction of hemorrhage volume (by 65%) in the TLT-treated group compared with controls. Intravenous administration of tPA, using an optimized dosing regimen, significantly increased hemorrhage incidence by 160%. The tPA-induced increase in hemorrhage incidence was not significantly affected by TLT, although there was a 30% decrease in hemorrhage incidence in combination-treated rabbits. There was no effect of TLT on hemorrhage volume measured in tPA-treated rabbits and no effect of any treatment on 24-hour survival rate. CONCLUSIONS: In the embolism model, TLT administration did not affect the tPA-induced increase in hemorrhage incidence. TLT may be administered safely either alone or in combination with tPA because neither treatment affected hemorrhage incidence or volume. Our results support the study of TLT in combination with Alteplase in patients with stroke.
Stroke 2008 Aug 7
The Effect of Visible and Infrared Polarized Light on the Healing Process of Full-Thickness Skin Wounds: An Experimental Study.
Iordanou P, Lykoudis EG, Athanasiou A, Koniaris E, Papaevangelou M, Fatsea T, Bellou P
Technological Educational Institute of Athens, Ioannina University School of Medicine, Ioannina, Greece.
Abstract Objective and Background Data: Polarized light has already been experimentally and clinically used in an effort to promote wound healing, but the findings have been equivocal. The aim of this study was to evaluate the effect of visible and infrared polarized light of a specific range of wavelength (580-3400 nm) on the secondary healing of full-thickness skin wounds in rats. Materials and Methods: Forty male Wistar rats were used, divided in two groups of 20 animals each. A standardized open full-thickness skin wound was created on the back of each animal. In the first group the rats were exposed to polarized light (40 mW/cm(2) and 2.4 J/cm(2)) for 7 min on a daily basis (total daily dose = 16.8 J/cm(2)), while the second group acted as controls. Clinical and histological evaluation of wound healing were performed on days 5, 10, 15, and 20 post-wound. The size of the wounds was measured with the use of planimetry, whereas epithelialization, inflammatory response, neovascularization, and collagen formation were histologically assessed. Results: According to our findings, the group exposed to light therapy showed statistically significantly faster epithelialization seen on days 10 and 15 post-wound compared to controls, as well as better quality of the healing process (although not statistically significantly) at all time points. Conclusion: In conclusion, this specific fraction of polarized light seems to have beneficial effects on wound healing, leading to faster epithelialization and qualitatively better wound healing.
Photomed Laser Surg 2008 Aug 8
Effect of Low-Level Laser Therapy on Mast Cells in Second-Degree Burns in Rats.
Aras MH
Ataturk University Dentistry Faculty Department of Oral and Maxillofacial Surgery, Erzurum, Turkey.
Photomed Laser Surg 2008 Aug 8
[Diagnosis and treatment of acute epididymoorchitis]
From 1963 we treated 330 patients aged from 15 to 85 years admitted to the urological clinic with acute epididymoorchitis of mild (n = 106), moderate (n = 82) and grave severity (n = 152). The diagnosis of purulent forms of epididymitis and epididymoorchitis was made basing on clinical and ultrasonic studies. Aspiration thin-needle puncture of epididymic membrane under ultrasonic control with calculation of leucocyte count was made for detection of purulent-process in 17 patients with epididymitis at the stage of diffuse inflammation. 198 patients with mild and moderate forms of acute epididymoorchitis received complex conservative treatment including laser therapy. 132 patients with severe epididymoorchitis were operated. In epididymoorchitis with total inflammatory-purulent process we made epididymectomy, in local – resection. The testis was removed in total necrosis or purulent lesion of its tissues. For comparison we analysed case histories of 150 patients with epididymoorchitis treated before 1983. Comparison of the treatment results in patients with acute inflammatory diseases of scrotal organs favours early surgical treatment.
Urologiia 2008 May-Jun (3) 49-52
Effect of 670-nm laser therapy and dexamethasone on tissue repair: a histological and ultrastructural study.
Reis SR, Medrado AP, Marchionni AM, Figueira C, Fracassi LD, Knop LA
Department of Propaedeutics and Integrated Clinic, School of Dentistry, Federal University of Bahia, Salvador, Brazil.
OBJECTIVE: In this study we investigated the role of extracellular matrix elements and cells during the wound healing phases following the use of low-level laser therapy (LLLT) and anti-inflammatory drugs. BACKGROUND DATA: There are few scientific studies that characterize the possible interactions of LLLT and anti-inflammatory medications. MATERIALS AND METHODS: Thirty-two rats submitted to a wound inflicted with a 6-mm-diameter punch. The animals were divided into four groups: sham treated, those treated with the GaAlAs laser (4 J/cm(2), 9 mW, lambda = 670 nm, spot size 28.27 x 10(2) cm(2)), those treated with dexamethasone (2 mg/kg), and those treated with both LLLT and dexamethasone. After 3 and 5 d, the cutaneous wounds were assessed by histopathology using polarized light and ultrastructural assessment using transmission electron microscopy. Changes seen in polymorphonuclear inflammatory cells, edema, mononuclear cells, and collagen fiber deposition were semi-quantitatively evaluated. RESULTS: The laser-treated group demonstrated increased collagen content and better arrangement of the extracellular matrix (p < 0.05). Fibroblasts in these tissues were increased in number and were more synthetically active. In the dexamethasone group, the collagen was shown to be non-homogenous and disorganized, with a scarcity of fibroblasts. In the group treated with both types of therapy, fibroblasts were more common and they exhibited vigorous rough endoplasmic reticulum, but they had less collagen production compared to those seen in the laser group. CONCLUSION: LLLT alone accelerates post-surgical tissue repair and reduces edema and the polymorphonuclear infiltrate even in the presence of dexamethasone.
Photomed Laser Surg 2008 Aug 26(4) 307-13
Low-intensity light therapy: exploring the role of redox mechanisms.
Tafur J, Mills PJ
Department of Psychiatry, Behavioral Medicine Laboratory, University of California at San Diego, La Jolla, California 92093-0804, USA. jtafur@ucsd.edu
Low-intensity light therapy (LILT) appears to be working through newly recognized photoacceptor systems. The mitochondrial electron transport chain has been shown to be photosensitive to red and near-infrared (NIR) light. Although the underlying mechanisms have not yet been clearly elucidated, mitochondrial photostimulation has been shown to increase ATP production and cause transient increases in reactive oxygen species (ROS). In some cells, this process appears to participate in reduction/oxidation (redox) signaling. Redox mechanisms are known to be involved in cellular homeostasis and proliferative control. In plants, photostimulation of the analogous photosynthetic electron transport chain leads to redox signaling known to be integral to cellular function. In gene therapy research, ultraviolet lasers are being used to photostimulate cells through a process that also appears to involve redox signaling. It seems that visible and near visible low-intensity light can be used to modulate cellular physiology in some nonphotosynthetic cells, acting through existing redox mechanisms of cellular physiology. In this manner, LILT may act to promote proliferation and/or cellular homeostasis. Understanding the role of redox state and signaling in LILT may be useful in guiding future therapies, particularly in conditions associated with pro-oxidant conditions.
Photomed Laser Surg 2008 Aug 26(4) 323-8
Efficacy of low-level laser therapy in Meniere’s disease: a pilot study of 10 patients.
Teggi R, Bellini C, Fabiano B, Bussi M
Ear, Nose, and Throat Department, IRRCS San Raffaele Hospital, Vita-Salute University, Milan, Italy. teggi.roberto@hsr.it
OBJECTIVE: To assess the efficacy of low-level laser therapy (LLLT) for Meniere’s disease (MD). MATERIALS AND METHODS: Twenty patients with unilateral MD were included in the study; all presented with uncontrolled vertigo. The patients were randomly divided into two groups: group 1 patients received LLLT 20 min a day with a 5-mW soft laser for 6 mo, while group 2 received betahistine 16 mg twice a day for 6 mo. According to American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) guidelines, the main outcome for vertigo control was considered to be the number of spells per month in the 6 mo before treatment compared with the same parameter in the 6 mo of therapy. The duration of spells expressed in minutes was also considered. Moreover, a hearing test was performed before and after therapy and results were reported as the pure tone average of 500-, 1000-, 2000-, and 3000-Hz frequencies. All results were valued at baseline, and after 3 and 6 mo of therapy. RESULTS: Compared to baseline, the number and duration of spells were significantly reduced in both groups; statistical significance was detected for the 3-mo control in both groups (p 0.05 with the multiple pair comparison test). Betahistine seems to have a faster action in spell reduction (p 0.05 comparing the 3-mo results between the two groups). Audiometric examination did not show a statistically significant difference between the two groups. CONCLUSIONS: In our experience, LLLT seems to prevent vertigo spells in MD, although results indicate that it has a slower action than betahistine. Dose-dependent therapeutic effects could explain the last result. In our opinion, increased blood flow in the inner ear is the main mechanism leading to the therapeutic results.
Photomed Laser Surg 2008 Aug 26(4) 349-53
Phototherapy in the treatment of acne vulgaris.
Sami NA, Attia AT, Badawi AM
Dermatology Unit, National Institute of Laser Enhanced Sciences, Cairo University, Egypt. nevien_a_sami@hotmail.com
BACKGROUND: Achieving an effective management of acne vulgaris with minimal complications remains a difficult challenge for physicians. Moreover, the rise in antibiotic-resistant strains reduce the future usefulness of current mainstay therapies, and accordingly, the need for alternative therapies is mandatory. Phototherapy has been shown to be an effective treatment for acne, and there has been a renewed interest in photodynamic therapy as a treatment modality for this condition. OBJECTIVES: To evaluate the effectiveness of pulsed dye laser (PDL), intense pulsed light (IPL) and light-emitting diode (LED) phototherapy for the treatment of moderate to severe acne vulgaris. METHODS: Forty-five patients with moderate to severe acne were randomly divided into 3 equal groups. Group 1 was treated with a PDL, group 2 was treated with IPL, and group 3 was treated with a blue-red combination LED. Treatment was continued until a > or = 90% clearance of patient lesions was achieved. Clinical assessments were conducted before starting treatment, at 1 month as a midpoint evaluation, and after the final treatment session. RESULTS: Patients treated with the PDL reached a > or = 90% clearance of their inflammatory lesions after a mean of 4.1 +/- 1.39 sessions, while patients treated with IPL required a mean of 6 +/- 2.05 sessions. Patients treated with the LED required a mean of 10 +/- 3.34 sessions. At the mid-point evaluation, the percent reduction in acne lesions treated with the PDL was 90% or more, in cases of IPL and the LED, the percent reductions were 41.7% and 35.3%, respectively. Laser and light phototherapy sessions were well tolerated with minimal adverse events experienced as being mild and usually self-limiting. CONCLUSIONS: The encouraging results of the present study contributes evidence of phototherapy as useful therapeutic option for treatment of moderate to severe acne, and validates further studies to evaluate treatments with a larger number of patients and for a longer period of follow-up.
J Drugs Dermatol 2008 Jul 7(7) 627-32
Stem cell proliferation under low intensity laser irradiation: a preliminary study.
Eduardo Fde P, Bueno DF, de Freitas PM, Marques MM, Passos-Bueno MR, Eduardo Cde P, Zatz M
Hospital Israelita Albert Einstein, Unit of Bone Marrow Transplantation, Sao Paulo 05651-901, SP, Brazil.
BACKGROUND AND OBJECTIVES: Phototherapy with low intensity laser irradiation has shown to be effective in promoting the proliferation of different cells. The aim of this in vitro study was to evaluate the potential effect of laser phototherapy (660 nm) on human dental pulp stem cell (hDPSC) proliferation. STUDY DESIGN/MATERIALS AND METHODS: The hDPSC cell strain was used. Cells cultured under nutritional deficit (10% FBS) were either irradiated or not (control) using two different power settings (20 mW/6 seconds to 40 mW/3 seconds), with an InGaAIP diode laser. The cell growth was indirectly assessed by measuring the cell mitochondrial activity through the MTT reduction-based cytotoxicity assay. RESULTS: The group irradiated with the 20 mW setting presented significantly higher MTT activity at 72 hours than the other two groups (negative control–10% FBS–and lased 40 mW with 3 seconds exposure time). After 24 hours of the first irradiation, cultures grown under nutritional deficit (10% FBS) and irradiated presented significantly higher viable cells than the non-irradiated cultures grown under the same nutritional conditions. CONCLUSIONS: Under the conditions of this study it was possible to conclude that the cell strain hDPSC responds positively to laser phototherapy by improving the cell growth when cultured under nutritional deficit conditions. Thus, the association of laser phototherapy and hDPSC cells could be of importance for future tissue engineering and regenerative medicine. Moreover, it opens the possibility of using laser phototherapy for improving the cell growth of other types of stem cells.
Lasers Surg Med 2008 Aug 40(6) 433-8
Effect of 830 nm low-level laser therapy in exercise-induced skeletal muscle fatigue in humans.
Leal Junior EC, Lopes-Martins RA, Vanin AA, Baroni BM, Grosselli D, De Marchi T, Iversen VV, Bjordal JM
Laboratory of Human Movement (LMH), University of Caxias do Sul (UCS), Rua Francisco Getulio Vargas, 1130, Caxias do Sul, 95070-560, Rio Grande do Sul, Brazil, ecplealj@ucs.br.
This study aimed to investigate the effect of 830 nm low-level laser therapy (LLLT) on skeletal muscle fatigue. Ten healthy male professional volleyball players entered a crossover randomized double-blinded placebo-controlled trial. Active LLLT (830 nm wavelength, 100 mW output, spot size 0.0028 cm(2), 200 s total irradiation time) or an identical placebo LLLT was delivered to four points on the biceps humeri muscle immediately before exercises. All subjects performed voluntary biceps humeri contractions with a load of 75% of the maximum voluntary contraction (MVC) force until exhaustion. After active LLLT the mean number of repetitions was significantly higher than after placebo irradiation [mean difference 4.5, standard deviation (SD) +/- 6.0, P = 0.042], the blood lactate levels increased after exercises, but there was no significant difference between the treatments. We concluded that 830 nm LLLT can delay the onset of skeletal muscle fatigue in high-intensity exercises, in spite of increased blood lactate levels.
Lasers Med Sci 2008 Jul 23
Effect of low-power gallium-aluminum-arsenium laser therapy (830 nm) in combination with bisphosphonate treatment on osteopenic bone structure: an experimental animal study.
Diniz JS, Nicolau RA, de Melo Ocarino N, do Carmo Magalhaes F, de Oliveira Pereira RD, Serakides R
Instituto de Pesquisa e Desenvolvimento (IP&D), Universidade do Vale do Paraiba, Sao Jose dos Campos, SP, Brazil.
Laser therapy is able to modulate cell metabolism and accelerate the repair of fracture. Little attention has been given to the effect of laser on bone with osteopenia or osteoporosis. The purpose of our study was to verify the effect of laser therapy in combination with bisphosphonate on osteopenic bone structure. The 35 Wistar female rats used were divided into five groups: (1) sham-operation rats (control), (2) ovariectomized (OVX’d) rats with osteopenia, (3) OVX’d rats with osteopenia treated with laser, (4) OVX’d rats with osteopenia treated with bisphosphonate and (5) OVX’d rats with osteopenia treated with bisphosphonate and laser. Groups 3 and 5 were given daily 6 mg doses of bisphosphonate orally. Groups 4 and 5 underwent low level laser therapy [gallium-aluminum-arsenium (GaAlAs) laser, 830 nm, 50 mW and 4 J/cm(2)] on the femoral neck and vertebral segments (T13-L2). Both treatments were performed over an 8-week period. Rats from the osteopenic control and osteopenic + laser groups presented marked osteopenia. In the osteopenic + bisphosphonate group, the trabecular bone volume in vertebra L2 was significantly greater than in the osteopenic control group. Notably, in the association between laser and bisphosphonate, the trabecular bone volume was significantly greater in vertebrae L2 and T13 and was similar to that in the sham-operation control group. It was concluded that the laser therapy associated with bisphosphonate treatment was the best method for reversing vertebral osteopenia caused by the ovariectomy.
Lasers Med Sci 2008 Jul 22
Does the use of laser photobiomodulation, bone morphogenetic proteins, and guided bone regeneration improve the outcome of autologous bone grafts? An in vivo study in a rodent model.
Torres CS, dos Santos JN, Monteiro JS, Amorim PG, Pinheiro AL
Centro Baiano de Estudos Odontologicos, Especializacao em Cirurgia e Traumatologia Bucomaxilofaciais, Universidade Federal da Bahia, Salvador, Brazil.
OBJECTIVE: The aim of the present investigation was to histologically assess the effect of laser photobiomodulation (LBPM) on the repair of autologous bone grafts in a rodent model. BACKGROUND DATA: A major problem in modern dentistry is the recovery of bone defects caused by trauma, surgical procedures, or pathologies. Several types of biomaterials have been used to improve the repair of these defects. These materials are often associated with procedures of guided bone regeneration (GBR). MATERIALS AND METHODS: Twenty four animals were divided into four groups: group I (control); group II (LPBM of the bone graft); group III (bone morphogenetic proteins [BMPs] + bone graft); and group IV (LPBM of the bed and the bone graft + BMPs). When appropriate the bed was filled with lyophilized bovine bone and BMPs used with or without GBR. The animals in the irradiated groups received 10 J/cm(2) per session divided over four points around the defect (4 J/cm(2)), with the first irradiation immediately after surgery, and then repeated seven times every other day. The animals were humanely killed after 40 d. Results: The results showed that in all treatment groups, new bone formation was greater and qualitatively better than the untreated subjects. Control specimens showed a less advanced repair after 40 d, and this was characterized by the presence of medullary tissue, a small amount of bone trabeculi, and some cortical repair. CONCLUSION: We conclude that LPBM has a positive biomodulatory effect on the healing of bone defects, and that this effect was more evident when LPBM was performed on the surgical bed intraoperatively, prior to the placement of the autologous bone graft.
Photomed Laser Surg 2008 Aug 26(4) 371-7
Laser-needle therapy for spontaneous osteonecrosis of the knee.
Banzer W, Hubscher M, Schikora D
Department of Sports Medicine, Goethe-University Frankfurt/Main, University of Paderborn, Frankfurt/Main, Germany. banzer@sport.uni-frankfurt.de
OBJECTIVE: This case report describes the treatment of a 63-year-old patient with spontaneous osteonecrosis of the knee (SONK). BACKGROUND DATA: SONK usually appears in the elderly patient without the typical risk factors for osteonecrosis. It is characterized by acute and sudden pain, mostly occurring at the medial side of the knee joint. Symptoms usually worsen with physical activity and improve with rest. Besides physical therapy, limited weight-bearing and the use of analgesics and nonsteroidal anti-inflammatory drugs, we propose low-level laser therapy (LLLT) as a conservative treatment option. METHODS: LLLT was carried out using laser needles emitting radiation with wavelengths of 685 and 885 nm, and a power density of 17.8 W/cm(2). Therapy sessions lasted 60 min and were performed daily over a period of 3 mo. The total irradiation dose emitted by 8 laser needles in 60 min of treatment was 1008 J. RESULTS: Magnetic resonance imaging revealed distinct restitution of the spongiosa edema 5 wk after treatment onset, and the final check-up at 35 wk demonstrated complete restoration of integrity. CONCLUSION: The present case report provides the first indication that laser-needle therapy may be a promising tool for complementary and alternative therapeutic intervention for those with SONK.
Photomed Laser Surg 2008 Aug 26(4) 301-6
The use of light photobiomodulation on the treatment of second-degree burns: a histological study of a rodent model.
Oliveira PC, Meireles GC, dos Santos NR, de Carvalho CM, de Souza AP, dos Santos JN, Pinheiro AL
Laser Center, School of Dentistry, Department of Propedeutica and Clinica Integrada, Federal University of Bahia, Salvador, Brazil.
OBJECTIVE: The aim of this investigation was to compare, by light microscopy, the effects of the use of laser photobiomodulation (LPBM) and polarized light (PL) on second-degree burns on rodents. BACKGROUND DATA: Burns are severe injuries that result in the loss of tissue fluids, destruction of tissues, infection, and shock. With severe and widespread third-degree burns death may occur. Several light sources have been suggested as being effective for improving wound healing. MATERIALS AND METHODS: Forty five rats were used in this study. A second-degree burn was created on the dorsum of each animal, and the animals were divided into four groups: PL (400-2000 nm, 40 mW, 2.4 J/cm(2)/min); LPBM-1 (780 nm, 35/40 mW, theta approximately 2 mm, 4 x 5 J/cm(2)); LPBM-2 (660 nm, 35/40 mW, theta approximately 2 mm, 4 x 5 J/cm(2)); and untreated animals acted as controls. The treatment was started immediately post-burn at four points around the burned area (laser: 5 J/cm(2) per site). The illumination with PL was performed according to the manufacturer’s instructions. Treatments were repeated at 24-h intervals for 7 d. The animals were sacrifice at 3, 5, and 7 d post-burn. The specimens were routinely cut and stained and analyzed by light microscopy using hematoxylin and eosin and Sirius red. RESULTS: The analysis of the results demonstrated that the damaged tissue was able to efficiently absorb and process the light at all tested wavelengths. LPBM at 660 nm showed better results at early stages of wound healing. However, the use of 780-nm laser light had beneficial effects throughout the experimental period, with the animals growing newly-formed tissue similar to normal dermis. CONCLUSION: Despite our findings that the use of both types of light energy improved the healing of second-degree burns at the early stages, long-term assessment is needed to verify if this improvement will influence the final results of treatment.
Photomed Laser Surg 2008 Aug 26(4) 289-99
The Ability of Low Level Laser Therapy to Prevent Muscle Tissue Damage Induced by Snake Venom.
Doin-Silva R, Baranauskas V, Rodrigues-Simioni L, da Cruz-Hofling MA
Department of Pharmacology, Faculty of Medical Sciences, State University of Campinas (UNICAMP), Campinas, SP, Brazil.
Antivenom therapy has been ineffective in neutralizing the severe local fast developing tissue damage following snakebite envenoming. Herein, some effects of in situ helium neon (HeNe) laser irradiation on rat nerve-muscle preparation injected with Bothrops jararacussu venom are described. The tibialis anterior muscle was injected with venom diluted in 0.9% saline solution (60 mug/0.02 mL) or saline solution alone. Sixty minutes after venom injection, laser (HeNe) treatment was administered at three incident energy densities: dose 1, a single exposure of 3.5 J cm(-2); dose 2, three exposures of 3.5 J cm(-2); dose 3, a single exposure of 10.5 J cm(-2). Muscle function was assessed through twitch tension recordings whereas muscle damage was evaluated through histopathologic analysis, morphometry of area of tissue affected and creatine kinase (CK) serum levels, and compared to unirradiated muscles. Laser application at the dose of 3.5 J cm(-2) reduced the area of injury by 64% (15.9 +/- 1.5%vs 44.2 +/- 5.7%), decreased the neuromuscular blockade (NMB) by 62% (11.5 +/- 2.5%vs 30.4 +/- 5.2%) and reduced CK levels by 58% (from 455 +/- 4.5% to 190.3 +/- 23.4%) when compared with unirradiated controls. Dose 2 showed a poorer benefit than dose 1, and dose 3 was ineffective in preventing the venom effects. Measurements of the absorbance of unirradiated and irradiated venom solution showed no difference in absorption spectra. In addition, no difference in the intensity of partial NMB in nerve-muscle preparation was shown by unirradiated and irradiated venom. The results indicate that the laser light did not alter venom toxicity. We conclude that HeNe laser irradiation at a dosage of 3.5 J cm(-2) effectively reduces myonecrosis and the neuromuscular transmission blocking effect caused by B. jararacussu snake venom. Thus, low level laser therapy may be a promising tool to minimize the severity of some of the local effects of snake envenoming.
Photochem Photobiol 2008 Jul 17
Electrophysiologic Effects of a Therapeutic Laser on Myofascial Trigger Spots of Rabbit Skeletal Muscles.
Chen KH, Hong CZ, Kuo FC, Hsu HC, Hsieh YL
From the Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Chiayi, Taiwan (K-HC, H-CH); College of Medicine, Chang Gung University, Taoyuan, Taiwan (K-HC, H-CH); and Department of Physical Therapy, HungKuang University, Taichung, Taiwan (C-ZH, F-CK); and the Department of Physical Therapy, Graduate Institute of Rehabilitation Science, China Medical University, Taichung, Taiwan (Y-LH).
Chen K-H, Hong C-Z, Kuo F-C, Hsu H-C, Hsieh Y-L: Electrophysiologic effects of a therapeutic laser on myofascial trigger spots of rabbit skeletal muscles. Am J Phys Med Rehabil 2008;87:000-000. OBJECTIVE:: To better understand the mechanisms of therapeutic lasers for treating human myofascial trigger points, we designed a blinded controlled study of the effects of a therapeutic laser on the prevalence of endplate noise (EPN) recorded from the myofascial trigger spot (MTrS) of rabbit skeletal muscle. DESIGN:: In eight rabbits, one MTrS in each biceps femoris muscle was irradiated with a 660-nm, continuous-wave, gallium-aluminum-arsenate (GaAlAs) laser, at 9 J/cm. The contralateral side of muscle was treated with a sham laser. Each rabbit received six treatments. The immediate and cumulative effects were assessed by the prevalence of EPN with electromyographic (EMG) recordings after the first and last treatments. RESULTS:: Compared with pretreatment values, the percentages of EPN prevalence in the experimental side after the first and last treatments were significantly reduced (P < 0.01 for both). The change in EPN prevalence in the experimental side was significantly greater than in the control side immediately after the first and last treatments (P < 0.05). However, no significant differences were noted between the first and last treatments (P > 0.05). CONCLUSIONS:: In our study, immediate and cumulative effects of a GaAlAs laser applied on MTrS were demonstrated on the basis of the assessment of EPN prevalence. It seems that laser irradiation may inhibit the irritability of an MTrS in rabbit skeletal muscle. This effect may be a possible mechanism for myofascial pain relief with laser therapy.
Am J Phys Med Rehabil 2008 Jul 9
Multimodal therapy for chronic tinnitus.
Hahn A, Radkova L, Achiemere G, Klement V, Alpini D, Strouhal J
Ear, Nose, and Throat Department, Third Medical Faculty, Charles University, Prague, Czech Republic. hahn@fnkv.cz
From 2001 to 2006, we performed a retrospective study of patients suffering from chronic unilateral or bilateral tinnitus that was previously ineffectively treated by oral drugs [betahistine (Betaserc), extract of Ginkgo biloba (EGb 761), tanakan (Tebokan), and cinnarizine-dimenhydrinate (Arlevert), singly or in combination]. We divided 150 tinnitus patients (80 men, 70 women) into seven treatment groups. Treatments consisted of application of intravenous pentoxifylline, lidocaine, or vinpocetine (Cavinton) and combination of these agents with physiotherapy and soft laser. Mean duration (+/- standard deviation) of tinnitus in these patients was 7.4 +/- 6.0 years; their mean age was 55.6 +/- 12.5 years. The aim of our study was to compare treatment modalities and define their effectiveness for tinnitus relief. The most effective treatment was defined as a combination of Cavinton and physiotherapy. We evaluated pure lidocaine infusion therapy as ineffective. None of the treatment modalities had an objective correlate of improvement, though improvement was reported by a visual analog scale.
Int Tinnitus J 2008 14(1) 69-72