Burns |
J Photochem Photobiol B. 2005 Feb 1;78(2):171-7.
Effect Of Low-Level Laser Therapy On The Healing Of Second-Degree Burns In Rats: A
Histological And Microbiological Study
Bayat M, Vasheghani MM, Razavi N, Taheri S, Rakhshan M.
Anatomy Department, Medical Faculty, Cell and Molecular Biology Research Center, Shaheed Beheshti University of Medical Sciences, P.O. Box 19395/4719, Tehran, Iran.
bayat_m@yahgo.com
This paper presents the results of a study on the effects of two different doses of low-level laser
therapy on healing of deep second-degree burns. Sixty rats were randomly allocated to one of
four groups. A deep second-degree burn was inflicted in each rat. In the control group burns
remained untreated; in two laser treated groups the burns were irradiated daily with low-level
helium-neon laser with energy densities of 1.2 and 2.4 J/cm2, respectively. In the fourth group the burns were treated topically with 0.2% nitrofurazone cream every day. The response to
treatments was assessed histologically at 7, 16 and 30 days after burning, and microbiologically
at Day 15. The number of macrophages at day 16, and the depth of new epidermis at day 30,
was significantly less in the laser treated groups in comparison with control and nitrofurazone
treated groups (P=0.000).
Staphylococcus epidermidis was found in the 70% of rat wounds in the laser treated groups in comparison with 100% of rats in the control group. S. aureus was found in the 40% rat wounds in the nitrofurazone treated group, but there was not found in the wounds of laser treated, and control groups. It is concluded that low-level laser therapy of deep seconddegree burn caused significant decrease in the number of macrophage and depth of new
epidermis. In addition, it decreased incidence of S. epidermidis and S. aureus.
J Clin Laser Med Surg. 2004 Feb;22(1):59-66.
Effects Of Low-Intensity Polarized Visible Laser Radiation On Skin Burns: A Light
Microscopy Study
Ribeiro MS, Da Silva Dde F, De Araujo CE, De Oliveira SF, Pelegrini CM, Zorn TM, Zezell DM.
Center for Lasers and Applications, IPEN-CNEN/SP, Cidade Universitaria, Sao Paulo, Brazil. mribeiro@ipen.br
OBJECTIVE: This study was carried out to investigate the influence of low-intensity polarized
visible laser radiation on the acceleration of skin wound healing. Background Data: Low-level
laser therapy (LLLT) at adequate wavelength, intensity, and dose can accelerate tissue repair.
However, there is still unclear information about light characteristics, such as coherence and
polarization. Some studies indicate that linearly polarized light can survive through long
propagation distance in biological tissue.
MATERIALS AND METHODS: Three burns about 6 mm in diameter were created on the back of
rats with liquid N(2). Lesion "L(//)" was irradiated by He-Ne laser (lambda = 632.8 nm), D= 1.0
J/cm(2), with linear polarization parallel to the spinal column of the rat. Lesion "L(inverted v)" was
irradiated using the same laser and dose, but the light polarization was aligned perpendicularly to the relative orientation. Lesion "C" was not irradiated in order to be considered as control. The
animals were sacrificed at day 3-17 after lesion creation. Samples were collected and prepared
for histological analysis.
RESULTS: Histological analysis showed that the healing of irradiated wounds was faster than
that of non-irradiated wounds. Moreover, it was observed that skin wound repair is dependent on
polarization orientation with respect to a referential axis as the animal's spinal column.
Burns. 2004 Jun;30(4):362-7.
Low Level Laser Therapy--A Conservative Approach To The Burn Scar?
Gaida K, Koller R, Isler C, Aytekin O, Al-Awami M, Meissl G, Frey M.
Department of Reconstructive and Plastic Surgery, Burn Unit, Division of Surgery,
University of Vienna, Austria.
Burn scars are known to be difficult to treat because of their tendency to worsen with hypertrophy and contracture. Various experimental and clinical efforts have been made to alleviate their effects but the problem has not been solved. Since patients keep asking for Low Level Laser Therapy (LLLT) and believe in its effectiveness on burn scars, and since former studies show contradictory results of the influence of LLLT on wound healing, this prospective study was designed to objectify the effects of LLLT on burn scars.
Nineteen patients with 19 burn scars were treated with a 400 mW 670 nm Softlaser twice a week over 8 weeks. In each patient a control area was defined, that was not irradiated. Parameters assessed were the Vancouver Scar Scale (VSS) for macroscopic evaluation and the Visual Analogue Scale (VAS) for pruritus and pain. Photographical and clinical assessments were recorded in all the patients. Seventeen out of 19 scars exhibited an improvement after treatment. The average rating on the VSS decreased from 7.10+/-2.13 to 4.68+/-2.05 points in the treated areas, whereas the VSS in the control areas decreased from 6.10+/-2.86 to 5.88+/-2.72. A correlation between scar duration and improvement through LLLT could be found. No
negative effects of LLLT were reported.
The present study shows that the 400 mW 670 nm softlaser has a positive, yet sometimes limited effect on burn scars concerning macroscopic appearance, pruritus, and pain.
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