Diabetic Foot Wounds Treated With Human Amniotic Membrane and Low-level Laser Therapy: A Pilot Clinical Study.

BACKGROUND: Low-level laser therapy (LLLT) and human amniotic membrane (HAM) application have been shown to be viable options for use in wound healing. PURPOSE: This study sought to compare LLLT and HAM to a control treatment (hydrogel, saline, and gauze) in persons with diabetes mellitus (DM) and foot ulcers. METHODS: Using a prospective pilot clinical study design, patients receiving care at a health center that specializes in the treatment of diabetic foot wounds between November 2016 and August 2017 were recruited. Eligible patients had to be 30 to 59 years of age; diagnosed with type 2 DM (postprandial capillary glucose levels between 140 and 350 mg/dL); and have uninfected, granulating stage 2 or 3 foot ulcers measuring less than 7 cm by 3 cm. Immunosuppressed and malnourished patients or those with neoplasms or in critical condition were not eligible to participate. Patients received the control treatment (2 mg hydrogel, saline, and gauze), HAM (patches of thawed HAM, applied with overlapping edges), or LLLT (phototherapy session, 2 mg hydrogel, saline, and gauze) for 28 days. Variables, wound area measurements, Pressure Ulcer Scale for Healing (PUSH) scores, and Visual Analog Scale (VAS) scores were used to assess wound improvement progress and pain on days 7, 14, 21, and 28. Descriptive statistics were used to analyze the participant anthropometric and clinical profiles. The Kolmogorov-Smirnov test was used to analyze the sample distribution. The Kruskal-Wallis test with Dunn's post-test was used to evaluate differences in PUSH and VAS scores and wound size for intergroup analysis, and the Mann-Whitney U test was used for the same outcomes in intragroup analysis. The level of significance was 5% (P < .05). RESULTS: Twenty-seven (27) patients participated (mean age, 51.4 years; mean body mass index, 26.5 kg/m2), with 9 patients in each treatment group. No statistically significant differences were noted in clinical or anthropometric variables among the groups, but mean baseline wound areas were different (2.6 cm² for the control, 1.9 cm² for the LLLT, and 5.5 cm² for the HAM groups). Intragroup comparisons showed a significant reduction in PUSH score in the LLT group between days 0 and 21 (8.2 vs 4.9; P < .01) and days 21 to 28 (4.9 vs 3.2; P < .001). In all treatment groups the percent reduction was significantly different between days 7 and 28. No outcomes were significantly different between groups. CONCLUSION: Diabetic foot ulcer wound area as well as PUSH and VAS scores showed more improvement for patients with DM receiving LLLT or HAM than for the control group, but the differences were not significant. Larger studies are needed to compare these treatment modalities.

Effect of low-power gallium-aluminum-arsenium noncoherent light (640 nm) on muscle activity: a clinical study.

BACKGROUND DATA: Studies have shown the significant effects of electromagnetic irradiation in the visible region, with laser as an irradiation source. However, the effect of LEDs (light-emitting diodes) irradiation in similar wavelengths is not known. OBJECTIVE: The purpose of this clinical study was to verify the effects of the LED (640 nm with 40 nm full bandwidth at half maximum) on muscle activity. METHODS: The study was done with 30 test subjects, of both genders, aged 23 ± 3 years, with a mean weight of 60 kg, divided into three groups (n = 10). Fatigue was induced through the maximum power of a bite, for 60 s in two overlaid occlusal platforms, coupled to a load cell and to a biologic signal-acquisition device. LED irradiation of the right masseter muscle was applied to all subjects. The left muscle received placebo treatment. Irradiation was applied in eight points on the right masseter muscle (transcutaneous), 1.044 J per point, 2.088 J per point, or 3.132 J per point, 0.116 W, 0.522 cm(2) spot size, 0.816 cm spot Ø, continuous wave, perpendicular to the skin. RESULTS: An increase in muscle activity was observed after irradiation with 1.044 J per point (p < 0.05). A significant increase (p < 0.01) in the time before fatigue was observed in the irradiated muscle with 2.088 J per point, without a change in the force of contraction (p > 0.05). This change was not observed with 1.044 J per point and 3.132 J per point. The results suggest a dose-dependent relation with this kind of noncoherent irradiation in the red region of the electromagnetic spectrum in the muscle-fatigue process. CONCLUSION: It was concluded that LED can be used as a clinical tool to increase muscle activity (1.044 J per point) and to prevent fatigue (2.088 J per point), without change in the muscle force.

Healing of surgical wounds made with lambda970-nm diode laser associated or not with laser phototherapy (lambda655 nm) or polarized light (lambda400-2000 nm).

OBJECTIVE: The aim of this study was to analyze the effect of two phototherapies, laser and polarized light, on diode laser (970lambda nm) wounds. BACKGROUND DATA: Lasers have been used in surgery, and some wavelengths may cause thermal damage to the tissue and affect healing. Several studies have shown that some wavelengths are effective in improving healing. Coherent and noncoherent light have been successfully used on the modulation of biological phenomena of several origins. ANIMALS AND METHODS: Thirty-one Wistar rats were divided into 3 groups (GI to GIII). A 20-mm x 2-mm wound was created on the dorsum of each animal with a diode laser (Sirolaser, Sirona, Bensheim, Germany). Group GI acted as control. On GII, laser light (lambda655 nm, 30 mW, phi approximately 3 mm, 12 J/cm(2)) was used and on GIII illumination with polarized light (lambda400-2000 nm, 40 mW, phi approximately 5.5 cm, 12 J/cm(2)) was used, every other day (GII) or daily (GIII) for 7 days. The animals were killed at 0, 7, and 14 days after surgery. Specimens were taken, routinely processed, stained and imunnomarked [HE (hematoxylin-eosin), sirius red, alpha-smooth muscle actin (SMA)], and underwent histological analysis. RESULTS: GII showed better response at day 14 when re-epithelialization was in a more advanced stage. The number of myofibroblasts was significantly different over the healing time (7 to 14 days); this number was smaller than that observed on G1. On GIII at day 7, the number of myofibroblasts was significantly higher than for GII. At day 14, a more pronounced deposition of collagen matrix was also seen, and inflammation was discrete and more advanced for GIII. CONCLUSION: The results of the present study showed that the effect of the use of laser light was more evident at early stages of healing and that the use of polarized light improved the resolution of the inflammatory reaction, increased the deposition of collagen, increased the number of myofibroblasts, and quickened re-epithelialization during the experimental time.

Análise eletromiográfica do músculo masseter após indução de fadiga com aplicação de laser de baixa potência – resultados preliminares / Eletromyografic analysis of masseter muscle after inducion of fatigue with low power laser aplication

Diversos estudos em animais têm demonstrado a efetividade dos lasers de baixa potência (LBP) sobre a otimização da atividade muscular esquelética. Contudo, poucos estudos foram direcionados à prevenção de fadiga em humanos. Assim, o presente estudo teve por objetivo analisar a aplicação do LBP na prevenção de fadiga muscular induzida em músculo masseter (MM). Participaram do estudo 10 voluntários divididos em dois grupos: irradiados com laser em 685nm (n=5) e irradiados com laser em 830nm (n=5). Foram colhidos sinais eletromiográficos durante o processo de fadiga induzida (60 s), antes e após o tratamento. O laser foi aplicado no MM direito, utilizando-se: 30 mW, 4 J/cm², 0,0028 cm², em 8 pontos (recobrindo todo o MM, com 1 cm de distância entre os pontos). As medidas pré-irradiação foram consideradas controle. Avaliou-se a atividade muscular, tempo de fadiga, força máxima e média e, em todos esses parâmetros estudados, verificou-se a ausência de diferença significativa. Embora o laser seja indicado pela literatura, nesse presente estudo concluímos que tal tratamento não se apresentou efetivo para prevenção de fadiga muscular no músculo masseter, não devendo, portanto, ser utilizado para este fim.

Several studies in animals have demonstrated the effectiveness of low power lasers (LBP) on the optimizationof skeletal muscle activity. However, few studies have been directed at the prevention of fatigue in humans.Therefore, the objective of this study was to analyze the implementation of LBP in the prevention of muscle fatigue induced at the masseter (MM). The participants of this study were 10 volunteers divided into two groups: irradiated with laser at 685 nm (n = 5) and irradiated with laser at 830 nm (n = 5). Electromyography signals were collected during fatigue induced process (60 s) before and after the treatment. The laser was applied in the right MM using: 30 mW, 4 J / cm ², 0.0028 cm ², 8 points (covering the whole MM, with 1 cm of distance between points). The pre-irradiation measures were considered as control measures. It was evaluated the muscle activity, duration of fatigue, maximum and average power and, in all these studied parameters, there was no signifi cant difference. Although laser is indicated by literature, in this present study it was concluded that such treatment was not effective in the prevention of muscle fatigue at the masseter and, therefore, it should not be utilized to this end.

The effects of low-level light emitting diode on the repair process of Achilles tendon therapy in rats.

Thirty Wistar rats (350 +/- 20 g) were subjected to total Achilles tendon tenotomy of the right fore limb. They were submitted to a daily dose of 20 J/cm(2) light emitting diode (LED) (640 +/- 20 nm) therapy. The LED was applied punctually and transcutaneously to the lesioned region. The animals were separated into six groups, C1 and L1, C2 and L2, C3 and L3. The C groups were used for control and the L groups, treated for 7, 14 and 21 consecutive days, respectively. The animals were killed on the 7th, 14th and 21st days after surgery. After the animals had been killed, their tendons were extracted and dissected, fixed in formaldehyde at 10%, and sent for histological analysis by light microscopy in which the repair process was analysed. This study demonstrated that LED interfered in the repair process of the tendon tissue, reducing the number of fibroblasts in the initial periods and improving the quality of the repair in all periods studied.