Lasers in Surgery and Medicine, 2013
Low-Level Laser Therapy for Fat Layer Reduction: A Comprehensive Review
Pinar Avci, MD,1,2,3 Theodore T. Nyame, MD,4 Gaurav K. Gupta, MD, PhD,1,2 Magesh, Sadasivam, MTech,1 and Michael R. Hamblin, PhD 1,2,5, 1 Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts, 02114, Department of Dermatology, Harvard Medical School, Boston, Massachusetts, 02114 3 Department of Dermatology, Dermatooncology and Venerology, Semmelweis University School of Medicine, Budapest, 1085, Hungary, 4Division of Plastic and Reconstructive Surgery, Harvard Medical School, Boston, Massachusetts, 02115, 5Harvard-MIT Division of Health Sciences and Technology, Cambridge, Massachusetts
Background and Objective: Low-level laser (light) therapy (LLLT) is a noninvasive, nonthermal approach to disorders requiring reduction of pain and inflammation and stimulation of healing and tissue regeneration. Within the last decade, LLLT started being investigated as an adjuvant to liposuction, for noninvasive body contouring, reduction of cellulite, and improvement of blood lipid profile. LLLT may also aid autologous fat transfer procedures by enhancing the viability of adipocytes. However the underlying mechanism of actions for such effects still seems to be unclear. It is important, therefore, to understand the potential efficacy and proposed mechanism of actions of this new procedure for fat reduction.
Methods: A review of the literature associated with applications of LLLT related to fat layer reduction was performed to evaluate the findings from preclinical and clinical studies with respect to the mechanism of action, efficacy, and safety.
Results: The studies as of today suggest that LLLT has a potential to be used in fat and cellulite reduction as well as in improvement of blood lipid profile without any significant side effects. One of the main proposed mechanism of actions is based upon production of transient pores in adipocytes, allowing lipids to leak out. Another is through activation of the complement cascade which could cause induction of adipocyte apoptosis and subsequent release of lipids.
Conclusion: Although the present studies have demonstrated safety and efficacy of LLLT in fat layer reduction, studies demonstrating the efficacy of LLLT as a standalone procedure are still inadequate. Moreover, further studies are necessary to identify the mechanism of action.
Gabriel Y.F. Ng, P.T., Ph.D., and Dicky T.C. Fung, P.T., Ph.D.
Objective: We examined the ultrastructural morphology (number of collagen fibrils, mean and mass-averaged diameter) of isolated and combined treatments of a therapeutic laser and herbs for medial collateral ligament (MCL) injury in rats.
Methods: Twenty-eight rats, divided into seven groups: laser (L), herb (H), laser herb (LH), laser control (LC), herb control (HC), laser sham (LS) and herb sham (HS), were studied. Right MCL of groups L, H, LH, LC and HC were transected, while that of LS and HS remained intact. Group L received 9 treatment sessions of GaAlAs laser with a dosage of 3.5 Jcm2; group H received herbal plaster treatment; groups LH had combined treatments of laser and herb; group LC had placebo laser; group LS had no treatment; groups HC and HS received only bandage without herb. All MCLs were analyzed using transmission electron microscopy at 3 weeks.
Results: Differences (p 0.05) existed in mean fibril diameters among groups. Core mass-averaged diameters of groups L and H were larger than the control groups (LC and HC). Fibril diameter of group LH (combined treatment) was even larger and approaching that of the intact MCL.
Conclusion: Combined therapeutic laser and herbal treatment hastened collagen fibril maturation in MCL repair.
Pugliese LS, Medrado AP, Reis SR, Andrade Zde A.
Pesqui Odontol Bras. 2003 Oct-Dec;17(4):307-13. Epub 2004 Apr 19.
Department of Basic Science, Foundation for the Development of Science, Salvador. The study of low-level laser therapy upon extracellular matrix elements is important to understand the wound healing process under this agent. However, little is known about the interference of laser light in relation to collagen and elastic fibers. Cutaneous wounds were performed on the back of 72 Wistar rats and a Ga-Al-As low-level laser was punctually applied with different energy densities. The animals were killed after 24, 48, 72 hours and 5, 7 and 14 days. Tissues were stained with hematoxilin-eosin, sirius red fast green and orcein and then analyzed. It was observed that the treated group exhibited larger reduction of edema and inflammatory infiltrate.
The treated animals presented a larger expression of collagen and elastic fibers, although without statistical significance (p > 0.05). Treatment with a dosage of 4 J/cm(2) exhibited more expressive results than that with 8 J/cm(2).
In this study, the authors concluded that low-level laser therapy contributed to a larger expression of collagen and elastic fibers during the early phases of the wound healing process.