Objective: To compare the efficacy of a simple irradiation scheme with that of a double-fractionated irradiation scheme on the healing of rat skin lesions using in vivo monitoring of tissue diffuse reflectance. Background Data: Low-level laser therapy (LLLT) is used in medicine for treating a wide range of pathological conditions. The practical benefits of laser treatment of acute and chronic conditions were obtained, using a single session of irradiation per day. Materials and Methods: Thirty Wistar rats were divided into three experimental groups (controls, simple laser irradiation scheme, and double-fractionated laser irradiation scheme). A skin lesion was created on the calf of the right hind leg of all rats. The laser irradiation parameters were λ = 635 nm and power = 15 mW. The exposure time was 600 s for the simple laser irradiation scheme and 300 s × 2 for the double-fractionated laser irradiation scheme on 3 consecutive days. The optical properties of tissue were studied by processing and analyzing the diffuse reflectance spectra of injured skin, acquired before and after each laser irradiation. Results: The results demonstrate that, using a simple laser irradiation scheme (single daily irradiation session: \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland, xspace} \usepackage{amsmath, amsxtra} \pagestyle{empty} \DeclareMathSizes {10} {9} {7} {6} \begin{document} \begin{align*} t_{{\exp}_1} = 600 \, {\rm s} \end{align*} \end{document}, power = 15 mW, λ = 635 nm), healing of the skin lesion began after 3 consecutive treatment days. The application of the double-fractionated laser irradiation scheme (2 daily irradiation sessions : \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland, xspace} \usepackage{amsmath, amsxtra} \pagestyle{empty} \DeclareMathSizes {10} {9} {7} {6} \begin{document} \begin{align*} t_{{\exp}_2} = t_{{\exp}_1}/2 = 300 \,{\rm s} \end{align*} \end{document}, power = 15 mW and λ = 635 nm) led to a reduction in treatment time to 2 days. Conclusion: In conclusion, a double-fractionated irradiation scheme is more efficient than simple irradiation scheme for LLLT in rat skin lesions.
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References
1.
GamA.N., ThorsenH., LonnbergF.1993. The effect of low-level laser therapy on musculoskeletal pain: a meta- analysis. Pain, 52:63–66.
2.
BasfordJ.R., SheffieldC.G., HarmsenW.S.1999. Laser therapy: a randomised, controlled trial of the effects of low-intensity Nd: YAG laser irradiation on musculoskeletal back pain. Arch. Phys. Med. Rehabil., 80:647–652.
3.
GuzzardellaG.A., FiniM., TorricelliP., GiavaresiG., GiardinoR.2002. Laser stimulation on bone defect healing: an in vitro study. Lasers Med. Sci., 17:216–220.
4.
BjordalJ.M., CouppèC., ChowR., TunèrJ., LjunggrenA.E.2003. A systematic review of low level laser therapy with location-specific doses for pain from chronic joint disorders. Aust. J. Physiother., 49:107–116.
QadriT., MirandaL., TunerJ., GustafssonA.2005. The short-term effects of low-level lasers as adjunct therapy in the treatment of periodontal inflammation. J. Clin. Periodontol., 32:714–719.
7.
PayerM., JakseN., PertlC., TruschneggA., LechnerE., EskiciA. 2005. The clinical effect of LLLT in endodontic surgery: a prospective study on 72 cases. Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod., 100:375–379.
8.
OzcelikO., Cenk HaytacM., KuninA., SeydaogluG.2008. Improved wound healing by low-level laser irradiation after gingivectomy operations: a controlled clinical pilot study. J. Clin. Periodontol., 35:250–254.
9.
PozzaD.H., Wehmeyer FregapaniP., WeberJ.B.B.et al.2008. Analgesic action of laser therapy (LLLT) in an animal model. Med. Oral Patol. Oral Cir. Bucal., 13:E648–E652.
10.
StergioulasA.2004. Low-level laser treatment can reduce edema in second degree ankle sprains. J. Clin. Laser Med. Surg., 22:125–128.
11.
LucasC., CoenenC.H.M., De HaanR.J.2000. The effect of low level laser therapy (LLLT) on stage III decubitus ulcers (pressure sores): a prospective randomised single blind, multicentre pilot study. Lasers Med. Sci., 15:94–100.
12.
SchindlA., SchindlM., Pernerstorfer-SchönH., MossbacherU., SchindlL.2000. Low intensity laser irradiation in the treatment of recalcitrant radiation ulcers in patients with breast cancer—long-term results of 3 cases. Photodermatol. Photoimmunol. Photomed., 16:34–37.
13.
GaidaK., KollerR., IslerC.et al.2004. Low level laser therapy—a conservative approach to the burn scar?Burns, 30:362–367.
14.
MoritaH., KohnoJ., HoriM., KitanoY.1993. Clinical application of low level laser therapy (LLLT) for atopic dermatitis. Keio J. Med., 42:174–176.
15.
StergioulasA.2004. Low-level laser treatment can reduce edema in second degree ankle sprains. J. Clin. Laser Med. Surg., 22:125–128.
16.
HoukL.D., HumphreysT.2007. Masers to magic bullets: an updated history of lasers in dermatology. Clin. Dermatol., 25:434–442.
17.
GurA., KarakocM., CevikR., NasK., SaracA.J., KarakocM.2003. Efficacy of low power laser therapy and exercise on pain and functions in chronic low back pain. Lasers Surg. Med., 32:233–138.
18.
ChowR.2008. Is relief of pain with low-level laser therapy (LLLT) a clinical manifestation of laser-induced neural inhibition?Proceedings of Light-Activated Tissue Regeneration and Therapy Conference. WaynantR., TataD.B.Berlin: Springer Science and Business Media, 277–281.
19.
TamG.2002. Effects of LLLT for pain: a clinical study on different pain types. Proc. SPIE., 4903:174–180.
DjavidG.E., MehrdadR., GhasemiM., Hasan-ZadehH., Sotoodeh-ManeshA., PouryaghoubG.2007. In chronic low back pain, low level laser therapy combined with exercise is more beneficial than exercise alone in the long term: a randomised trial. Aust. J. Physiother., 53:155–160.
22.
GurA., KarakocM., CevikR., NasK., SaracA.J., KarakocM.2003. Efficacy of low power laser therapy and exercise on pain and functions in chronic low back pain. Lasers Surg. Med., 32:233–238.
23.
AlvaroB.L.M.R., SocratesC.P.S., JonJ., VegardV.I., BjordalJ.M.2007. Low level laser therapy [LLLT] in inflammatory and rheumatic diseases: a review of therapeutic mechanisms. Curr. Rheumatol. Rev., 3:147–154.
24.
AimbireF., AlbertiniR., PachecoM.T.T.et al.2006. Low-level laser therapy induces dose-dependent reduction of TNFα levels in acute inflammation. Photomed. Laser Surg., 24:33–37.
25.
BjordalJ.M., Lopes-MartinsR.A.B., IversenV.V.2006. A randomised, placebo controlled trial of low level laser therapy for activated Achilles tendinitis with microdialysis measurement of peritendinous prostaglandin E2 concentrations. Br. J. Sports Med., 40:76–80.
26.
SimunovicZ., TrobonjacaT.1999. Soft-tissue injuries from sports activities and traffic accidents–treatment with low-level laser therapy: a multicenter double-blind placebo-controlled clinical study on 132 patients. Proc. Soc. Photo Opt. Instrum. Eng., 4166:286–293.
27.
HawkinsD., AbrahamseH.2005. Biological effects of helium-neon laser irradiation on normal and wounded human skin fibroblasts. Photomed. Laser Surg., 23:251–239.
28.
HoureldN., AbrahamseH.2007. Laser light influences cellular viability and proliferation in diabetic-wounded fibroblast cells in a dose- and wavelength-dependent manner. Laser Med. Sci., 23:11–18.
29.
MooreP., RidgwayT.D., HigbeeR.G., HowardE.W., LucroyM.D.2005. Effect of wavelength on low-intensity laser irradiation-stimulated cell proliferation in vitro. Lasers Surg. Med., 36:8–12.
30.
MendezT., PinheiroA., PachecoM., NascimentoP., RamalhoL.2004. Dose and wavelength of laser light have influence on the repair of cutaneous wounds. J. Clin. Laser Med. Surg., 22:19–25.
31.
KaruT.1989. Photobiology of low-power laser effects. Health Phys., 56:691–704.
32.
IlicS., LeichliterS., StreeterJ., OronA., deTaboadaL., OronU.2006. Effect of power densities, continuous and pulse frequencies, and number of sessions of low-level laser therapy on intact rat brain. Photomed. Laser Surg., 24:458–466.
33.
BasfordJ.R.2005. Low intensity laser therapy: still not an established clinical tool. Lasers Surg. Med., 16:331–342.
34.
van GeelI.P, OppelaarH., MarijnissenJ.P, StewartF.A.1996. Influence of fractionation and fluence rate in photodynamic therapy with Photofrin or mTHPC. Radiat. Res., 145:602–609.
35.
CurnowA., HallerJ.C., BownS.G.2000. Oxygen monitoring during 5-aminolaevulinic acid induced photodynamic therapy in normal rat colon. Comparison of continuous and fractionated light regimes. J. Photochem. Photobiol. B, 58:3149–3155.
36.
BabilasP., SchachtV., LiebschG.et al.2003. Effects of light fractionation and different fluence rates on photodynamic therapy with 5-aminolaevulinic acid in vivo. Br. J. Cancer, 88:1462–1469.
37.
OberdannerC.B., PlaetzerK., KiesslichT., KrammerB.2005. Photodynamic treatment with fractionated light decreases production of reactive oxygen species and cytotoxicity in vitro via regeneration of glutathione. Photochem. Photobiol., 81:609–613.
38.
XiaoZ., HallsS., DickeyD., TulipJ., RonaldB, MooreR.B.2007. Fractionated versus standard continuous light delivery in interstitial photodynamic therapy of dunning prostate carcinomas. Clin. Cancer Res., 13:7496–7505.
39.
WeingartenM.S., PapazoglouE.S., ZubkovL.et al.2008. Correlation of near infrared absorption and diffuse reflectance spectroscopy scattering with tissue neovascularization and collagen concentration in a diabetic rat wound healing model. Wound Repair Regen., 16:234–242.
40.
Hui LiH., XieS.2007. Response of diffuse reflectance light of two-layered tissue to optical properties of inner layer. Proc. Soc. Photo Opt. Instrum. Eng., 6534:65340.
41.
XiaJ., YaoG.2007. Angular distribution of diffuse reflectance in biological tissue, Appl. Opt., 46:6552–6560.
42.
YuB., FuH., BydlonT., BenderT.J., RamanujamN.2008. Diffuse reflectance spectroscopy with a self-calibrating fiber optic probe, Opt. Lett., 33:1783–1785.
43.
YangH., XieS., LiH., LuZ.2007. Determination of human skin optical properties in vivo from reflectance spectroscopic measurements. Chinese Optics Letters, 5:181–183.
44.
JacquesS.L.Spectroscopic determination of tissue optical properties using optical fiber spectrometer [on-line]http://omlc.ogi.edu/news/feb06/skinspect/index.htm.
