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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. |
