Proceedings Volume 8932

Mechanisms for Low-Light Therapy IX

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Proceedings Volume 8932

Mechanisms for Low-Light Therapy IX

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Volume Details

Date Published: 3 March 2014
Contents: 8 Sessions, 27 Papers, 0 Presentations
Conference: SPIE BiOS 2014
Volume Number: 8932

Table of Contents

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Table of Contents

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  • Front Matter: Volume 8932
  • Mechanisms and Dosimetry
  • In Vitro Studies I
  • In Vitro Studies II
  • Animal Studies I
  • Animal Studies III
  • Clinical Studies
  • Poster Session
Front Matter: Volume 8932
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Front Matter: Volume 8932
This PDF file contains the front matter associated with SPIE Proceedings Volume 8932, including the Title Page, Copyright information, Table of Contents, Invited Panel Discussion, and Conference Committee listing.
Mechanisms and Dosimetry
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Application and possible mechanisms of combining LLLT (low level laser therapy), infrared hyperthermia and ionizing radiation in the treatment of cancer
Edward H. Abraham, Van H. Woo, Cheryl Harlin-Jones, et al.
Benefit of concomitant infrared hyperthermia and low level laser therapy and ionizing radiation is evaluated in this study. The purpose/objectives: presentation with locally advanced bulky superficial tumors is clinically challenging. To enhance the efficacy of chemotherapy and IMRT (intensity-modulated radiation therapy) and/or electron beam therapy we have developed an inexpensive and clinically effective infrared hyperthermia approach that combines black-body infrared radiation with halogen spectrum radiation and discrete wave length infrared clinical lasers LLLT. The goal is to produce a composite spectrum extending from the far infrared to near infrared and portions of the visible spectrum with discrete penetrating wavelengths generated by the clinical infrared lasers with frequencies of 810 nm and/or 830 nm. The composite spectrum from these sources is applied before and after radiation therapy. We monitor the surface and in some cases deeper temperatures with thermal probes, but use an array of surface probes as the limiting safe thermal constraint in patient treatment while at the same time maximizing infrared entry to deeper tissue layers. Fever-grade infrared hyperthermia is produced in the first centimeters while non-thermal infrared effects act at deeper tissue layers. The combination of these effects with ionizing radiation leads to improved tumor control in many cancers.
Photo-excitation of electrons in cytochrome c oxidase as a theory of the mechanism of the increase of ATP production in mitochondria by laser therapy
Andrzej Zielke
The hypothesis explains the molecular basis for restoring mitochondrial function by laser therapy. It also explains how laser therapy reverses both excessive oxidation (lack of NADH/FADH2) and excessive reduction (lack of O2) states of cytochrome c oxidase complex. It is proposed that photons interact with heme molecules of cytochrome c oxidase. A molecule of heme contains a porphyrin ring and an atom of iron in the center. The iron atom (Fe) can switch oxidation states back and forth between ferrous (Fe2+) and ferric (Fe3+) by accepting or releasing an electron. The porphyrin ring is a complex aromatic molecule that has 26 pi electrons which are “delocalized”, spinning in the carbon rings creating a resonating electromagnetic cloud. Photons with similar wavelengths are absorbed by the cloud increasing its energy. The energy is then passed on to the centrally located atom of iron existing in a reduced state (Fe2+). The electrons on the orbits of the iron atom accept this electromagnetic energy, and change orbitals to a higher energetic level. If the energy is sufficient, electrons leave the atom entirely. If this occurs, Fe2+ become oxidized to Fe3+ releasing electrons, thus restoring electron flow and the production of ATP. At the same time, electrons freed from complex IV may have sufficient energy to be picked by NAD+/FADH and re-enter the chain at the complex I or II amplifying the flow of electrons.
Combination of nitric oxide therapy, anti-oxidative therapy, low level laser therapy, plasma rich platelet therapy and stem cell therapy as a novel therapeutic application to manage the pain and treat many clinical conditions
Salaheldin Halasa, Eva Dickinson
From hypertension to diabetes, cancer to HIV, stroke to memory loss and learning disorders to septic shock, male impotence to tuberculosis, there is probably no pathological condition where nitric oxide does not play an important role. Nitric oxide is an analgesic, immune-modulator, vasodilator, anti-apoptotic, growth modulator, angiogenetic, anti-thrombotic, anti-inflammatory and neuro-modulator. Because of the above actions of nitric oxide, many clinical conditions associated with abnormal Nitric oxide (NO) production and bioavailability. Our novel therapeutic approach is to restore the homeostasis of nitric oxide and replace the lost cells by combining nitric oxide therapy, anti-oxidative therapy, low level laser therapy, plasma rich platelet therapy and stem cell therapy.
VCSELs in the visible to IR as a light source for low light therapy
VCSELs (Vertical Cavity Surface Emitting Lasers ) provide a very versatile optical source for Low Light Therapy applications. This talk will discuss performance characteristics and packaging demonstrations for VCSELs primarily operating in the 680nm and 850nm regimes. At 680nm individual VCSELs produce >10mW, while >0.35W can be provided from a 0.4mm2 emission area. Spectral width is typically 1-2nm even for a multi-mode or array device. At 850nm these numbers increase to >30mW and >0.8W. Even higher powers can be achieved under pulsed modulation, i.e. 0.55W for a 680nm VCSEL or 1.2W for an 850nm VCSEL. While we report on results achieved at 680nm and 850nm, extension to wavelengths ranging from 660nm to 1000nm is easily achieved. The packaging flexibility of VCSELs also makes them of significant interest to the Low Light Therapy community. We will report on the incorporation of VCSELs into surface mount packages, including typical LED packages such as the PLCC, or ceramic chip carriers. VCSELs in PLCC packages have been attached to flexible circuits to provide a broad area illumination. We will also report on a unique chip on board package which easily allows for the addition of optical elements such as diffusers, diffraction gratings or lenses. This package is 2mm on a side, sufficiently small for incorporation into catheters or implantation.
Near infrared laser penetration and absorption in human skin
Babak Nasouri, Thomas E. Murphy, Halil Berberoglu
For understanding the mechanisms of low level laser/light therapy (LLLT), accurate knowledge of light interaction with tissue is necessary. In this paper, we present a three dimensional, multi-layer Monte Carlo simulation tool for studying light penetration and absorption in human skin. The skin is modeled as a three-layer participating medium, namely epidermis, dermis, and subcutaneous, where its geometrical and optical properties are obtained from the literature. Both refraction and reflection are taken into account at the boundaries according to Snell’s law and Fresnel relations. A forward Monte Carlo method was implemented and validated for accurately simulating light penetration and absorption in absorbing and anisotropically scattering media. Local profiles of light penetration and volumetric absorption densities were simulated for uniform as well as Gaussian profile beams with different spreads at 155 mW average power over the spectral range from 1000 nm to 1900 nm. The results show the effects of beam profiles and wavelength on the local fluence within each skin layer. Particularly, the results identify different wavelength bands for targeted deposition of power in different skin layers. Finally, we show that light penetration scales well with the transport optical thickness of skin. We expect that this tool along with the results presented will aid researchers resolve issues related to dose and targeted delivery of energy in tissues for LLLT.
Evaluation of laser photobiomodulation (λ 780 nm) on repair of dental replantation in rats
Fabíola Bastos de Carvalho, Rebeca Mota Vasconcelos M.D., Laila Santos, et al.
Up to date the success of tooth replantation is still limited. The majority of the teeth is lost due to progressive external root resorption. The aim of this study was to assess, histologically, the effect of laser photobiomodulation on repair after tooth replantation. Sixty Wistar Albinus rats had the right upper incisor extracted and then divided into 4 groups: G1 - absence of storage medium; G2 - milk u s e d as storage medium; G3 – milk used as storage medium a n d followed by GaAlAs laser irradiation on dental surfaces and at the entrance of alveolus; G4 - milk used as storage medium associated with laser irradiation as in G3 before and after replantation on the buccal and palatal mucosa every 48 hours for 15 days. The animals were sacrificed at 15, 30 and 60 days after replantation. The results showed that after 15 days G4 exhibit more intense chronic inflammation, with presence of clastic cells and moderate inflammatory root resorption (p<0.05) when compared to G3, which presented absence of those parameters. At day 30 in G1, G2 and G4 mild to moderate chronic inflammation and severe external root resorption were observed. G3 remained with no inflammation and inflammatory root resorption with 30 and 60 days of healing experimental times. The results suggest that laser irradiation on the dental entrance of the dental alveolus prior to tooth replantation has a positive biomodulative effect on the healing process in rats.
Wavelength, beam size and type dependences of cerebral low-level light therapy: A Monte Carlo study on visible Chinese human
Ting Li, Yue Zhao, Meixue Duan, et al.
Low level light therapy (LLLT) has been clinically utilized for many indications in medicine requiring protection from cell/tissue death, stimulation of healing and repair of injuries, pain reduction, swelling and inflammation. Presently, use of LLLT to treat stroke, traumatic brain injury, and cognitive dysfunction is attracting growing interest. Near-infrared light can penetrate into the brain tissue, allowing noninvasive treatment to be carried out with few treatment-related adverse events. Optimization of LLLT treatment effect is one key issue of the field; however, only a few experimental tests on mice for wavelength selection have been reported. We addressed this issue by low-cost, straightforward and quantitative comparisons on light dosage distribution in Visible Chinese human head with Monte Carlo modeling of light propagation. Optimized selection in wavelength, beam type and size were given based on comparisons among frequently-used setups (i.e., wavelengths: 660 nm, 810 nm, 980 nm; beam type: Gaussian and flat beam; beam diameter: 2 cm, 4 cm, 6cm).This study provided an efficient way to guide optimization of LLLT setup and selection on wavelength, beam type and size for clinical brain LLLT.
In Vitro Studies I
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Irradiation at 660 nm modulates different genes central to wound healing in wounded and diabetic wounded cell models
Nicolette N. Houreld
Wound healing is a highly orchestrated process and involves a wide variety of cellular components, chemokines and growth factors. Laser irradiation has influenced gene expression and release of various growth factors, cytokines and extracellular matrix proteins involved in wound healing. This study aimed to determine the expression profile of genes involved in wound healing in wounded and diabetic wounded fibroblast cells in response to irradiation at a wavelength of 660 nm. Human skin fibroblast cells (WS1) were irradiated with a diode laser (wavelength 660 nm; fluence 5 J/cm2; power output 100 mW; power density 11 mW/cm2; spot size 9.1 cm2; exposure duration 7 min 35 s). Total RNA was isolated and 1 μg reverse transcribed into cDNA which was used as a template in real-time qualitative polymerase chain reaction (qPCR). Eighty four genes involved in wound healing (extracellular matrix and cell adhesion; inflammatory cytokines and chemokines; growth factors; and signal transduction) were evaluated in wounded and diabetic wounded cell models. Forty eight hours post-irradiation, 6 genes were significantly upregulated and 8 genes were down-regulated in irradiated wounded cells, whereas 1 gene was up-regulated and 33 genes down-regulated in irradiated diabetic wounded cells. Irradiation of stressed fibroblast cells to a wavelength of 660 nm and a fluence of 5 J/cm2 modulated the expression of different genes involved in wound healing in different cell models. Modulation of these genes leads to the effects of laser irradiation seen both in vivo and in vitro, and facilitates the wound healing process.
Genetic expression of adipose derived stem cell and smooth muscle cell markers to monitor differentiation potential following low intensity laser irradiation
Mesenchymal stem cells (MSCs) have the capacity to differentiate into a variety of cell types that could potentially be used in tissue engineering and regenerative medicine. Low intensity laser irradiation (LILI) has been shown to induce a significant increase in cell viability and proliferation. Growth factors such as retinoic acid (RA) and transforming growth factor β1 (TGF-β1) play important roles in the differentiation of cells. The aim of this study was to investigate whether LILI in combination with growth factors could induce the differentiation of adipose derived stem cells (ADSCs) cocultured with smooth muscle cells (SMCs). The study used primary and continuous ADSC cell lines and a SMC line (SKUT-1) as control. Cells were co-cultured directly at a ratio of 1:1 using established methods, with and without growth factors and then exposed to LILI at 5 J/cm2 using a 636 nm diode laser. The cellular morphology, viability and proliferation of the co-cultures were assessed over a period of one week. The study also monitored the expression of cell specific markers over the same period of time. Genetic expression of the markers for both adipose derived stem cells (β1 Integrin and Thymidine 1) and smooth muscle cells (Heavy Myosin Chain) was monitored using flow cytometry. Cell viability and proliferation increased significantly in the co-cultured groups that were exposed to laser alone, as well as in combination with growth factors. Furthermore, there was a significant decrease in the expression of stem cell markers in the ADSCs over time. The results indicate that LILI in combination with growth factors not only increases the viability and proliferation of co-cultured cells but also decreases the expression of ADSC stem cell markers. This could indicate the possible differentiation of ADSCs into SMCs.
Alterations in cell migration and cell viability of wounded human skin fibroblasts following visible red light exposure
Vijendra Prabhu, Bola Sadashiva Satish Rao, Krishna Kishore Mahato
The present study intended to examine the effect of visible red light on structural and cellular parameters on wounded skin fibroblast cells. To achieve the stated objective, uniform scratch was created on confluent monolayered human skin fibroblast cells, and were exposed to single dose of He-Ne laser (15 mm spot, 6.6808 mWcm-2) at 1, 2, 3, 4, 5, 6 and 7 Jcm-2 in the presence and absence of 10% fetal bovine serum (FBS). Beam profile measurements of the expanded laser beam were conducted to ensure the beam uniformity. The influence of laser dose on the change in temperature was recorded using sensitive temperature probe. Additionally, following laser exposure cell migration and cell survival were documented at different time intervals on wounded human skin fibroblast cells grown in vitro. Beam profile measurements indicated more or less uniform power distribution over the whole beam area. Temperature monitoring of sham irradiated control and laser treatment groups displayed negligible temperature change indicating the absence of thermal effect at the tested laser doses. In the absence of 10% FBS, single exposure of different laser doses failed to produce any significant effects on cell migration or cell survival. However, in the presence of serum single exposure of 5 J/cm2 on wounded skin fibroblasts significantly enhanced the cell migration (P<0.05) compared to the other tested doses (1, 2, 3, 4, 6 and 7 J/cm2) and sham irradiated controls. In conclusion, the LLLT acts by improving cell migration and cell proliferation to produce measurable changes in wounded fibroblast cells.
In Vitro Studies II
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Nitric oxide measurements in hTERT-RPE cells and subcellular fractions exposed to low levels of red light
Jeffrey C. Wigle, Cherry C. Castellanos, Michael L. Denton, et al.
Cells in a tissue culture model for laser eye injury exhibit increased resistance to a lethal pulse of 2.0-μm laser radiation if the cells are first exposed to 2.88 J/cm2 of red light 24 hr prior to the lethal laser exposure. Changes in expression of various genes associated with apoptosis have been observed, but the biochemical link between light absorption and gene expression remains unknown. Cytochome c oxidase (CCOX), in the electron transport chain, is the currentlyhypothesized absorber. Absorption of the red light by CCOX is thought to facilitate displacement of nitric oxide (NO) by O2 in the active site, increasing cellular respiration and intracellular ATP. However, NO is also an important regulator and mediator of numerous physiological processes in a variety of cell and tissue types that is synthesized from l-arginine by NO synthases. In an effort to determine the relative NO contributions from these competing pathways, we measured NO levels in whole cells and subcellular fractions, with and without exposure to red light, using DAF-FM, a fluorescent dye that stoichiometrically reacts with NO. Red light induced a small, but consistently reproducible, increase in fluorescence intensity in whole cells and some subcellular fractions. Whole cells exhibited the highest overall fluorescence intensity followed by (in order) cytosolic proteins, microsomes, then nuclei and mitochondria.
Association phenothiazine and laser on growth of C. tropicalis fluconazole-resistant
Rafael Araújo Gomes Júnior, Susana C. P. S. de Oliveira, Juliana S. C. Monteiro, et al.
Candidiasis is caused by Candida species found on the skin, gastrointestinal tract and mucous cavities of the humans and may be acute, chronic, localized or systemic. Alhough C. albicans is the species most often identified as responsible for this type of infection C. Tropicalis has been considered an emerging cause. The effect of the association of phenothiazine - PTZ and laser on fluconazole-resistant C.tropicalis growth was tested. 2.5 x 106 CFU/mL 100mg/mL of phenothiazine with the pre-irradiation time of 10 min were irradiated with laser light (660 nm; 4.8 and 12 J/cm2 (L1 and L2 respectively) 40 mW) followed by incubation in RPMI for 24h. The following conditions were tested: control (control), laser (L1 and L2), phenothiazine (F1 and F2), and PACT (F1L1 and F2L2). Statistically significant diferences were seen between groups (L-F +) and (F + L +) for both conditions of the laser, with a growth inhibition of the yeast around 67 and 51%, respectively, however, when using only the laser there was an increase of 18% in the survival of these cells. PACT's efficacy on fluconazole-resistant C. tropicalis depended on both the time of pre-irradiation and concentration of the PTZ.
In vitro influence of photodynamic antimicrobial chemotherapy on staphylococcus aureus by using phenothiazines derivatives associated with laser/LED Light
Susana C. P. S. de Oliveira, Juliana S. C. Monteiro, Gustavo M. Pires-Santos, et al.
The aim of this study was to evaluate the effect of photodynamic antimicrobial chemotherapy (PACT) using phenothiazinium dyes - PTZ irradiated with red laser (λ660nm) or red-orange LED (λ632±2nm) on Staphylococcus aureus in vitro. triplicate tests were performed in 10 groups: control, Laser (L1+P- and L2+P-) bacterial suspensions were irradiated only with laser energy 2.4 and 4.8 J/cm2 respectively, (Led1+P- and Led2+P-) irradiated only with LED energy 2.4 and 4.8 J/cm2 respectively, (L1+P+ and L2+P+) irradiated with laser in the presence of 1μg/ml of photosensitizer, (Led1+P+ and Led2+P+) irradiated with LED in the presence of 1μg/ml of photosensitizer and finally (L-P+) only in the presence of PTZ dye. Bactericidal effect of the PACT was assessed by counting colony-forming units. The results showed no significant difference on regards different energy densities on group PACT for both lights. PACT groups (L2+P+ and Led2+P+) compared to the Control showed significant reduction of CFUs. LED/Laser groups (L2+P- and Led2+P-) compared to control and PTZ groups showed also significant differences as groups LED/Laser (4.8J/cm2) increased the average of CFUs. Although the results of this study have shown a reduction in average number of colonyforming units by the appropriate Laser or LED-dye treatment combination, it this topic requires further investigation.
Animal Studies I
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Treating metabolic syndrome’s metaflammation with low level light therapy: preliminary results
Metabolic syndrome comprises a constellation of morbidities such as insulin resistance, hyperinsulinemia, atherogenic dyslipidemia, dysglycemia and obesity (especially abdominal). Metabolic alterations are observed in major insulin target organs, increasing the risk of cardiovascular diseases, type-2 diabetes and therefore mortality. Tissue alterations are characterized by immune cells infiltrates (especially activated macrophages). Released inflammatory mediators such as TNF-α induce chronic inflammation in subjects with metabolic syndrome, since inflammatory pathways are activated in the neighboring cells. The intra-abdominal adipose tissue appears to be of particular importance in the onset of the inflammatory state, and strategies contributing to modulate the inflammatory process within this adipose tissue can mitigate the metabolic syndrome consequences. Considering the low level light therapy (LLLT) recognized benefits in inflammatory conditions, we hypothesized this therapeutic approach could promote positive effects in modulating the inflammatory state of metabolic syndrome. That being the scope of this study, male C57BL/6 mice were submitted to a high-fat/high-fructose diet among 8 weeks to induce metabolic syndrome. Animals were then irradiated on the abdominal region during 21 days using an 850 nm LED (6 sessions, 300 seconds per session, 60 mW output power, ~6 J/cm2 fluence, ~19 mW/cm2 fluence rate). Before and during treatment, blood was sampled either from the retroorbital plexus or from tail puncture for glucose, total cholesterol and triglycerides analysis. So far our results indicate no alterations on these metabolic parameters after LLLT. For further investigations, blood was collected for plasma inflammatory cytokine quantification and fresh ex vivo samples of liver and intra-abdominal adipose tissue were harvested for immunohistochemistry purposes.
Raman and histological study of the repair of surgical bone defects grafted with biphasic synthetic micro-granular HA + β - calcium triphosphate and irradiated or not with λ780 nm laser
Antonio Luiz Barbosa Pinheiro, Luiz Guilherme P. Soares, Aparecida Maria C. Marques, et al.
The treatment of bone loss due to different etiologic factors is difficult and many techniques aim to improve repair, including a wide range of biomaterials and, recently, phototherapies. This work assessed, by Raman spectroscopy and histology, the mineralization of bone defects. Forty rats divided into 4 groups each subdivided into 2 subgroups according to the time of sacrifice were used. Bone defects were made on the femur of each animal with a trephine drill. On animals of group Clot the defect was filled only by blood clot, on group Laser the defect filled with the clot was further irradiated. On animals of groups Biomaterial and Laser + Biomaterial the defect was filled by biomaterial and the last one was further irradiated (λ780 nm, 70 mW, Φ ~ 0.4 cm2, 20 J/cm2-session, 140 J/cm2-treatment). At both 15th and 30th days following sacrifice, samples were taken and analyzed by Raman spectroscopy and light microscopy. Raman peaks of inorganic and organic contents and a more advanced stage of repair were seen on group Laser + Biomaterial. It is concluded that the use of Laser phototherapy associated to biomaterial was effective to improve the repair of bone defects.
Evaluation of low level laser therapy irradiation parameters on rat muscle inflammation through systemic blood cytokines
Matias Mantineo, João P. Pinheiro, António M. Morgado
Low level laser therapy (LLLT) has been used for inflammation treatment. Here, we evaluate the effect of different doses, using continuous (830 and 980 nm) and pulsed illumination (830 nm), in the treatment of inflammation induced in the gastrocnemius muscle of Wistar rats, through cytokines concentration in systemic blood and histological analysis of muscle tissue. Animals were randomly divided into five groups per wavelength (5 animals per group: 10, 20, 30, 40 and 50 mW) plus a control group. LLLT was applied during five days, with constant exposure time and irradiated area (3 minutes; 0.5026 cm2). Blood was collected on days 0, 3 and 6. TNF-α, IL-1β, IL-2 and IL-6 cytokines were quantified by ELISA. Rats were killed on day 6. Muscle inflammatory cells were counted using optical microscopy. Treatment effects occurred for all applied doses (largest effect at 40 mW: 7.2 J, 14 J/cm2 per irradiation), with reduction of proinflammatory TNF-α, IL-1β and IL-6 cytokines and lower number of inflammatory cells. Results were better for 830 nm. Identical methodology was used with pulsed illumination. Average power (40 mW) and duty cycle were kept constant (80%) at five frequencies (5, 25, 50, 100 and 200 Hz). Treatment effects were observed at higher frequencies, with no significant differences between them. However, the treatment effect was lower than for continuous illumination. LLLT effect on inflammation treatment can be monitored by measuring systemic blood cytokines. A larger treatment effect was observed with continuous illumination, where results seem to be compatible with a biphasic dose response.
Animal Studies III
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Efficacy of multiple exposure with low level He-Ne laser dose on acute wound healing: a pre-clinical study
Vijendra Prabhu, Bola Sadashiva Satish Rao, Krishna Kishore Mahato
Investigations on the use of Low Level Laser Therapy (LLLT) for wound healing especially with the red laser light have demonstrated its pro-healing potential on a variety of pre-clinical and surgical wounds. However, until now, in LLLT the effect of multiple exposure of low dose laser irradiation on acute wound healing on well-designed pre-clinical model is not much explored. The present study aimed to investigate the effect of multiple exposure of low dose Helium Neon laser on healing progression of full thickness excision wounds in Swiss albino mice. Further, the efficacy of the multiple exposure of low dose laser irradiation was compared with the single exposure of optimum dose. Full thickness excision wounds (circular) of 15 mm diameter were created, and subsequently illuminated with the multiple exposures (1, 2, 3, 4 and 5 exposure/ week until healing) of He-Ne (632.8 nm, 4.02 mWcm-2) laser at 0.5 Jcm-2 along with single exposure of optimum laser dose (2 J/cm-2) and un-illuminated controls. Classical biophysical parameters such as contraction kinetics, area under the curve and the mean healing time were documented as the assessment parameters to examine the efficacy of multiple exposures with low level laser dose. Experimental findings substantiated that either single or multiple exposures of 0.5 J/cm2 failed to produce any detectable alterations on wound contraction, area under the curve and mean healing time compared to single exposure of optimum dose (2 Jcm-2) and un-illuminated controls. Single exposure of optimum, laser dose was found to be ideal for acute wound healing.
Clinical Studies
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Low-level light therapy (LLLT) for cosmetics and dermatology
Over the last few years, low-level laser (light) therapy (LLLT) has been demonstrated to be beneficial to the field of aesthetic medicine, specifically aesthetic dermatology. LLLT encompasses a broad spectrum of procedures, primarily cosmetic, which provide treatment options for a myriad of dermatological conditions. Dermatological disorders involving inflammation, acne, scars, aging and pigmentation have been investigated with the assistance of animal models and clinical trials. The most commercially successful use of LLLT is for managing alopecia (hair loss) in both men and women. LLLT also seems to play an influential role in procedures such as lipoplasty and liposuction, allowing for noninvasive and nonthermal methods of subcutaneous fat reduction. LLLT offers a means to address such conditions with improved efficacy versatility and no known side-effects; however comprehensive literature reports covering the utility of LLLT are scarce and thus the need for coverage arises.
Effect of laser acupuncture versus traditional acupuncture in neck pain of cervical spondylosis
Ahmed M. El-Kharbotly, Alyaa A. El-Gendy, Mouchira A. Mohammed, et al.
This prospective cohort study aimed to compare the efficiency of laser versus traditional acupuncture in treating cervical spondylosis (CS) pain. Forty female patients were randomized into two equal groups that received 3 sessions / week for 4 weeks. Group A received needle acupuncture therapy with electrical stimulation for 20 min at standard acupoints, ear points and Ashi point on the average 3 points. Group B received low level laser therapy (LLLT) acupuncture at the same acupoints. The results demonstrated that tenderness disappeared in 65% of patients in group A and 75% of patients in group B with improved percentage of 85.5% and 89.2%. Pain on VAS related to direction of motion at 6 directions was improved in all cases where with improvement percentage 76.45% and 85.88%. Pain on VAS at rest was improved in all patients with improvement percentage of 80.41% and 84.28%. NDIQ score improved in all patients with improvement percentage of 69.78% and 73.77%. Follow up of VAS after 6 months from the last session revealed persistent improvement in 55% of patients of group A vs 80% of patients of group B. Mean serum TNF-α was decreased in 85% of patients of group A vs 95% of patients of group B where serum beta endorphins was increased in all patients. It is concluded that both modes of treatment for CS gave improvement regarding pain intensity, disability and quality of life being more evident in LLLT followed for 6 months supported with improved serum TNFα and beta endorphin.
Comparison of clinical effectiveness of laser acupuncture and amitriptyline in diabetic peripheral neuropathy (DPN): a sham controlled randomized clinical trial
Imran Hassan Khan, Shahzad Anwar, Asif Hanif, et al.
Background: Painful neuropathy is a very common complication in diabetic patients. Various treatment strategies like manual therapies, conservative management, drug therapy and exercise have been opted for this problem. Studies have shown clinical effectiveness of laser acupuncture as well. On the other hand, Amitryptaline is also a commonly used treatment for this disease. We aim to compare the efficacy of both treatments. Objective: To assess the effect of laser acupuncture in patients suffering from painful diabetic neuropathy and its comparison with standard of care. Patients and Method: This study was conducted in Diabetic and Endocrine Management Center (DEMC) Lahore General Hospital, Lahore, Pakistan. A randomized control trial (RCT) was opted and a total of 164 patients were chosen using Non-probability purposive sampling technique. Pain was graded by using a patient friendly Visual Analogue Score (VAS), scoring from 0 to 10. Treatment was done involving organized fortnightly follow ups. Data of all patients was recorded on Performa and was entered and analyzed for descriptive statistics in PASW 18 (IBM®. SPSS). Results: A total of 164 subjects were included in the study who were subdivided into three groups labeled as A, B and C for laser therapy treatment, amitryptaline treatment and controls respectively. The mean age of subjects was 51.54±10.46 in Group A, 49.38±10.56 in Group B and 51.70±11.43 in Group C. The difference of mean ages in all study groups was statistically insignificant (p-value= 0.469). The average pain score in patients who received laser therapy was 5.95±0.91 before treatment, whereas after treatment it was 4.31±0.98. The mean pain score in subjects having Amitryptaline before starting the treatment was 6.87±0.71 and after treatment, it was 6.23±0.98. The mean score for daily life activities in subjects who received laser therapy was 9.562.37 before treatment, while after treatment it was 7.56±1.54. The average score for daily life activities in patients having Amitryptaline before starting the treatment was 9.05±1.93 and after treatment, it was 8.11±1.71. Average depression and anxiety score in patients receiving laser therapy was 9.29±2.28 before treatment, whereas after treatment it was found to be 7.42±1.91. Similarly, the mean depression and anxiety score in patients of Amitryptaline group before starting the treatment was 9.38±2.21 and after treatment, it was 8.38±2.14. Conclusion: The mean score in our study reveals that laser therapy shows better outcomes in improvement of pain relief, depression, anxiety and daily life activities compared to amitryptaline in patients of diabetic neuropathy.
Poster Session
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Assessment laser phototherapy on bone defects grafted or not with biphasic synthetic micro-granular HA + β-Tricalcium phosphate: histological study in an animal model
Luiz Guilherme P. Soares, Aparecida M. C. Marques, Jouber Mateus S. Aciole, et al.
Beside of biomaterials, Laser phototherapy has shown positive results as auxiliary therapy on bone repair. The aim of this study was to evaluate, through histological analysis, the influence of Laser phototherapy in the process of repair of bone defects grafted or not with Hydroxyapatite. Forty rats were divided into 4 groups each subdivided into 2 subgroups according to the time of sacrifice. Surgical bone defects were made on femur of each animal with a trephine drill. On animals of group Clot the defect was filled only by blood, on group Laser the defect filled with the clot and further irradiated. In group Biomaterial the defect was filled with HA + β-TCP graft. In group Laser + Biomaterial, the defect was filled with biomaterial and further irradiated. The irradiation protocols were performed every 48 hours during for 15 days. Animal death occurred after 15 and 30 days. The specimens were routinely processed and evaluated by light microscopy. Qualitative analysis showed that group Laser + Biomaterial was in a more advanced stage of repair at the end of the experimental time. It was concluded that the Laser irradiation improved the repair of bone defects grafted or not.
Phenothiazinium dyes in association with diode red laser against B16F10 melanoma cells: in vitro study
Anderson F. Miranda, Gustavo M. P. Santos, Susana C. P. S. de Oliveira, et al.
In Brazil solar incidence is high and continuous throughout the year. Body exposure to sunlight may be a key point in the rates of individuals affected by melanoma and other types of skin cancer in many countries. Brazil already occupies the 15th place in the ranking of melanoma cases and the limitations presented by drugs used in the therapy of this cancer, new approaches are being used in an attempt to decrease the mortality of this malignancy. The aim of this study was to evaluate the effects of phenothiazinium dyes (PD) associated with laser light on murine melanoma (B16F10) in vitro by measuring cell growth using colorimetric assay before and after photodynamic therapy. We used a diode laser (λ660nm, 2.4 J/cm2, 40 mW, 60 s, CW) associated with PD at 12.5 μg/mL, time pre-irradiation of 30 minutes). The following groups were tested: control (LF-), PD (L-F+), Laser (L+F-), Laser + PD (L+F+). The results showed a significant reduction in cell growth in the group treated by the photodynamic therapy compared to the control at 24 and 48 h (p < 0.001). Were showing at 30 min PD has a dose-dependent response on B16F10 cells, but at 24 h did not demonstrated this response.
Evaluation of enamel by scanning electron microscopy green LED associated to hydrogen peroxide 35% for dental bleaching
Juliana S. C. Monteiro, Susana C. P. S. de Oliveira, Fátima A. A. Zanin, et al.
Dental bleaching is a frequently requested procedure in clinical dental practice. The literature is contradictory regarding the effects of bleaching agents on both morphology and demineralization of enamel after bleaching. The aim of this study was to analyze by SEM the effect of 35% neutral hydrogen peroxide cured by green LED. Buccal surfaces of 15 pre-molars were sectioned and marked with a central groove to allow experimental and control groups on the same specimen. For SEM, 75 electron micrographs were evaluated by tree observers at 43X, 220X and 1000X. Quantitative analysis for the determination of the surface elemental composition of the samples through X-ray microanalysis by SEM was also performed. The protocol tested neither showed significant changes in mineral composition of the samples nor to dental enamel structure when compared to controls. SEM analysis allowed inferring that there were marked morphological differences between the enamel samples highlighting the need for the use of the same tooth in comparative morphological studies. The tested protocol did not cause morphological damage the enamel surface when compared to their respective controls.
Enhanced angiogenic effect of adipose-derived stromal cell spheroid with low-level light therapy in hindlimb ischemia mice
Adipose-derived stromal cells (ASCs) are attractive cell source for tissue engineering. However, one obstacle to this approach is that the transplanted ASC population can decline rapidly in the recipient tissue. The aim of this study was to investigate the effects of low-level laser therapy (LLLT) on transplanted human ASCs (hASCs) spheroid in a hindlimb ischemia animal model. LLLT, hASCs spheroid and hASCs spheroid transplantation with LLLT (spheroid + LLLT) were applied to the ischemic hindlimbs in athymic mice. The survival, differentiation and secretion of vascular endothelial growth (VEGF) of spheroid ASCs were evaluated by immunohistochemistry. The spheroid + LLLT group enhanced the tissue regeneration, including angiogenesis, compared with other groups. The spheroid contributed tissue regeneration via differentiation and secretion of growth factors. In the spheroid + LLLT group, the survival of spheroid hASCs was increased by the decreased apoptosis of spheroid hASCs in the ischemic hindlimb. The secretion of growth factors was stimulated in the spheroid + LLLT group compared with the ASCs group and spheroid group. These data suggest that LLLT is an effective biostimulator of spheroid hASCs in tissue regeneration that enhances the survival of ASCs and stimulates the secretion of growth factors in the ischemic hindlimb.
Effect of LED phototherapy (λ630 ± 20nm) on mast cells during wound healing in hypothyroid
Gardênia Matos Paraguassú, Isabele Cardoso Viera De Castro, Rebeca Mota Vasconcelos, et al.
Hypothyroidism has been associated with the disruption of the body's metabolism, including the healing process. LED phototherapy has been studied using several healing models, but their effects on mast cells proliferation associated to hypothyroidism remains unknown. The aim of this study was to assess the effect LED (λ630±20nm) phototherapy on mast cells proliferation during tissue repair in hypothyroid rats. Under general anesthesia, a standard surgical wound (1cm2) was created on the dorsum of 24 male Wistar rats divided into 4 groups of 6 animals each: EC-Control Euthyroid; ED-Euthyroid+LED; HC-Control Hypothyroid and HD-Hypothyroid+LED. The irradiation started immediately after surgery and was repeated every other day for 7 days, when animals death occurred. Hypothyroidism was induced in rats with propylthiouracil (0.05g/100mL) administered orally for 4 weeks and maintained until the end of the experiment. The specimens removed were processed to wax and stained with toluidine blue for mast cell identification. The mast cell proliferation was significantly higher in HC group than in EC group (Mann Whitney, p<0.05), but when ED group was compared to HD group, no significant difference was found. Our results showed that there was increase of mast cells in the presence of hypothyroidism, prolonging the inflammatory phase of repair, and the LED light has a biomodulative effect on mast cell population, even when hipothyroidism was present.
Laser photobiomodulation as an adjunct of the wound healing impairment of rats exposed to a cafeteria diet
V. Uzeda, G. M. Paraguassu, J. N. Dos Santos, et al.
Obesity is associated to a delayed wound healing and prolonged inflammatory phase. Laser light has shown positive results in the photobiomodulation of tissue repair; however, its use associated with systemic disorders such as obesity is still little explored in the literature. The aim of this study was to validate an experimental system for studying weight gaining by consuming a high fat diet called "cafeteria diet" (CD) for the induction of obesity. Forty-eight rats were weaned, divided into two experimental groups: standard diet (SD) and Cafeteria Diet (CD). Free feeding was carried out during 20 weeks and the mass gaining was accompanied. After general anesthesia standardized surgical wounds were created (1cm2) in the dorsal midline region of each animal. Both groups (SD; CD) were divided into 2 subgroups of 12 animals, G1 and G3 (non-irradiated) and G2 and G4 (irradiated). The irradiation protocols (λ660 nm, 40 mW, CW; 24 J/cm2) started immediately after surgery and were repeated every other day during 14 days. The rats were killed at the 8th or 15th days after surgery. The abdominal fat was removed and weighed to verify the success of the induction technique. The specimens were taken and routinely processed histology (hematoxylin/eosin) was performed. It was concluded that the ingestion of fast-food increased abdominal fat in rats and modified the inflammatory pattern of the healing. Laser phototherapy in the parameters employed decreased inflammatory intensity quickening wound healing in obese rats.