Low-level laser (light) therapy (LLLT) is a fast-growing technology used to treat a multitude of conditions that require stimulation of healing, relief of pain and inflammation, and restoration of function. Although the skin is the organ that is naturally exposed to light more than any other organ, it still responds well to red and near-infrared wavelengths. The photons are absorbed by mitochondrial chromophores in skin cells. Consequently electron transport, adenosine triphosphate (ATP) nitric oxide release, blood flow, reactive oxygen species increase and diverse signaling pathways get activated. Stem cells can be activated allowing increased tissue repair and healing. In dermatology, LLLT has beneficial effects on wrinkles, acne scars, hypertrophic scars, and healing of burns. LLLT can reduce UV damage both as a treatment and as a prophylaxis. In pigmentary disorders such as vitiligo, LLLT can increase pigmentation by stimulating melanocyte proliferation and reduce depigmentation by inhibiting autoimmunity. Inflammatory diseases such as psoriasis and acne can also benefit. The non-invasive nature and almost complete absence of side-effects encourages further testing in dermatology.
Easetak are exported all over the world and different industries with quality first. Our belief is to provide our customers with more and better high value-added products. Let's create a better future together.
Keywords: Acne, Dermatology, Herpes, Laser, LLLT, Low level laser therapy, Phototherapy, Skin disease, Skin Rejuvenation, Pigmentation, Vitiligo
Increasingly, non-invasive therapies for skin disease and skin rejuvenation are used, especially in Western countries where relatively high disposable incomes are combined with the desire for an ideal appearance fostered by societal pressures. Although the skin is the organ that is naturally most exposed to light, it still responds well to red and near-infrared wavelengths delivered at the correct parameters with therapeutic intent. Low-level laser therapy (LLLT) was discovered in the late s, but only in recent times has it been widely applied in dermatology. The introduction of light emitting diode (LED) devices has reduced many of the concerns formerly associated with lasers, such as expense, safety concerns and the need for trained personnel to operate them. In fact, many LED devices are designed for home use and are widely sold on the internet. This review will cover the use of LLLT as possibly the ultimate non-invasive approach to treating the skin.
LLLT, phototherapy or photobiomodulation refers to the use of photons at a non-thermal irradiance to alter biological activity. LLLT uses either coherent light sources (lasers) or non-coherent light sources consisting of filtered lamps or light-emitting diodes (LED) or, on occasion, a combination of both. The main medical applications of LLLT are reducing pain and inflammation, augmenting tissue repair and promoting regeneration of different tissues and nerves, and preventing tissue damage in situations where it is likely to occur.1,2 In the last few decades, non-ablative laser therapies have been used increasingly for the aesthetic treatment of fine wrinkles, photoaged skin and scars, a process known as photorejuvenation (Table 1). More recently, this approach has also been used for inflammatory acne (Table 1).3 LLLT involves exposing cells or tissue to low-levels of red and near infrared (NIR) light. This process is referred to as low-level because the energy or power densities employed are low compared to other forms of laser therapy such as ablation, cutting, and thermally coagulating tissue. Recently, medical treatment with LLLT at various intensities has been found to stimulate or inhibit an assortment of cellular processes.4
Examples of LLLT Devices for Dermatological Applications
Supplier Product name Wavelength (nm) Power Density (mW/cm2) Standard Dose(J/cm 2) Application PhotoMedex (Manchester, UK) Omnilux 415 (±5) 40 48 Acne, photodamage, non-melanoma skin cancers, skin rejuvenation, vitiligo and wound healing post elective surgery 633 (±6) 105 126 830 (±5) 55 66 Edge Systems (Signal Hill, CA) Delphia del Sol 420 7.4 J per treatment area Acne, improving skin texture, firmness and resilience, increasing lymphatic system activity, fine lines, wrinkles and superficial hyperpigmentation 600700 700 Flip 4 (Sainte-Julie, Quebec, Canada) Max7 420700 4 Acne, rejuvenation, injured skin healing including the shortening of the post skin resurfacing erythema duration Light BioSciences (Virginia Beach, VA) Gentlewaves 588 (±10) Variable Anti-aging OPUSMED (Montreal, Canada) LumiPhase-R 660 150 Skin firmness, rhytid depth, wrinkles Revitalight (Chicago, IL) Revitalight 747 420 80 7.2 J per 90 sec. per treatment area Fine lines, wrinkles, and age spots on the face, neck and hands Hand Spa 590 80 Food Spa 625 80 Evolution 940 80 Soli-Tone (Woburn, MA) LumiFacial 470 84 Acne, anti-aging, hyperpigmentation, rosacea Lumilift 525 27 590 10 640 89 DUSA (Wilmington, MA) BLU-U 417 10 Acne Curelight (Rehovot, Israel) iClearXL 405420 60 Acne, anti-aging, skin rejuvenation, acceleration of healing of post peel and post surgical suture sites Clear100XL 890900 Lumenis (Santa Clara, CA) ClearLight 405420 200 60 Acne Clear100 LIGHTWAVE Technologies (Phoneix, AZ) LIGHTWAVE Professional Deluxe LED System 417 Anti-aging, skin rejuvenation 630 880 Dynatronics (Salt Lake City, UT) Synergie LT2 660 500 mW (total power) 6 J per treatment area Anti-aging, skin firmness, wrinkles, skin tone and texture for face and neck 880 Open in a new tabThe mechanism associated with the cellular photobiostimulation by LLLT is not yet fully understood. From observation, it appears that LLLT has a wide range of effects at the molecular, cellular, and tissue levels. The basic biological mechanism behind the effects of LLLT is thought to be through absorption of red and NIR light by mitochondrial chromophores, in particular cytochrome c oxidase (CCO) which is contained in the respiratory chain located within the mitochondria,57 and perhaps also by photoacceptors in the plasma membrane of cells. Consequently a cascade of events occur in the mitochondria, leading to biostimulation of various processes (Figure 1).8 Absorption spectra obtained for CCO in different oxidation states were recorded and found to be very similar to the action spectra for biological responses to the light.5 It is hypothesized that this absorption of light energy may cause photodissociation of inhibitory nitric oxide from CCO9 leading to enhancement of enzyme activity,10 electron transport,11 mitochondrial respiration and adenosine triphosphate (ATP) production (Figure 1).1214 In turn, LLLT alters the cellular redox state which induces the activation of numerous intracellular signaling pathways, and alters the affinity of transcription factors concerned with cell proliferation, survival, tissue repair and regeneration (Figure 1).2,5,6,15,16
Mechanism of action of LLLT.
Basic biological mechanism behind the effects of LLLT is thought to be through absorption of red and NIR light by mitochondrial chromophores, in particular cytochrome c oxidase (CCO) which is contained in the respiratory chain located within the mitochondria 57. It is hypothesized that this absorption of light energy may cause photodissociation of inhibitory nitric oxide from CCO 9 leading to enhancement of enzyme activity 10, electron transport 11, mitochondrial respiration and ATP production 1214. In turn, LLLT by altering the cellular redox state can induce the activation of numerous intracellular signaling pathways; alter the affinity of transcription factors concerned with cell proliferation, survival, tissue repair and regeneration2,5,6,15,16.
Although LLLT is now used to treat a wide variety of ailments, it remains somewhat controversial as a therapy for 2 principle reasons. First, there are uncertainties about the fundamental molecular and cellular mechanisms responsible for transducing signals from the photons incident on the cells to the biological effects that take place in the irradiated tissue. Second, there are significant variations in terms of dosimetry parameters: wavelength, irradiance or power density, pulse structure, coherence, polarization, energy, fluence, irradiation time, contact vs non-contact application, and repetition regimen. Lower dosimetric parameters can result in reduced effectiveness of the treatment and higher ones can lead to tissue damage.1 This illustrates the concept of the biphasic dose response that has been reported to operate in LLLT 1,18,19. Many of the published studies on LLLT include negative results. It is possibly because of an inappropriate choice of light source and dosage. It may also be due to inappropriate preparation of the patients skin before application of LLLT, such as: lack of removal of makeup and oily debris, which can interfere with the penetration of the light source, and failure to account for skin pigmentation.17 Inappropriate maintenance of the LLLT equipment can reduce its performance and interfere with clinical results as well. It is important to consider that there is an optimal dose of light for any particular application.
Laser radiation or non-coherent light has a wavelength and radiant exposure dependent capability to alter cellular behavior in the absence of significant heating.20 Phototherapy employs light with wavelengths between 3901,100 nm and can be continuous wave or pulsed. In normal circumstances, it uses relatively low fluences (0.0450 J/cm2) and power densities (< 100 mW/cm2).21 Wavelengths in the range of 390 nm to 600 nm are used to treat superficial tissue, and longer wavelengths in the range of 600nm to 1,100nm, which penetrate further, are used to treat deeper-seated tissues (Figure 2).4 Wavelengths in the range 700 nm to 750 nm have been found to have limited biochemical activity and are therefore not often used.1 Various light sources used in LLLT include inert gas lasers and semiconductor laser diodes such as helium neon (HeNe; 633 nm), ruby (694 nm), argon (488 and 514 nm), krypton (521, 530, 568, 647 nm), gallium arsenide (GaAs; > 760 nm, with a common example of 904 nm), and gallium aluminum arsenide (GaAlAs; 612870 nm).17 A wide range of LED semiconductors are available at lower wavelengths, whose medium contains the elements indium, phosphide and nitride. One question that has not yet been conclusively answered is whether there is any advantage to using coherent laser light over non-coherent LED light.22 While some medical practitioners treat deep tissue lesions using focused lasers in points, in dermatology the use of LEDs is becoming increasingly common due to the relatively large areas of tissue that require irradiation.
Tissue penetration depths of various wavelengths.
Skin starts showing its first signs of aging in the late 20s to early 30s and it usually presents with wrinkles, dyspigmentation, telangiectasia, and loss of elasticity. Common histologic and molecular-level features are reduction in the amount of collagen, fragmentation of collagen fibers, elastotic degeneration of elastic fibers, upregulation of matrix metalloproteinases (MMPs), especially MMP-1 and MMP-2, dilated and tortuous dermal vessels, and atrophy and disorientation of the epidermis.23,24 Both chronological and environmental influences are responsible for the aging process of skin; however photodamage seems to be one of the most important causes of these changes.
Several modalities have been developed in order to reverse the dermal and epidermal signs of photo- and chronological aging. The main concept of most of these modalities is removing the epidermis and inducing a controlled form of skin wounding in order to promote collagen biosynthesis and dermal matrix remodeling. The most commonly used interventions as of today are retinoic acid (a vitamin A derivative), dermabrasion, chemical peels, and ablative laser resurfacing with carbon dioxide (CO2) or erbium: yttrium-aluminum-garnet (Er:YAG) lasers or a combination of these wavelengths.2527 However, these procedures require intensive post-treatment care, prolonged downtime and may lead to complications such as long-lasting erythema, pain, infection, bleedings, oozing, burns, hyper- or hypopigmentation and scarring.28,29 These limitations created a need for the development of alternative rejuvenation procedures that were safer, more effective, had fewer side effects and minimum postoperative care and downtime, which in turn led to the emergence of non-ablative rejuvenation technologies.3032 Non-ablative skin rejuvenation aims to improve photoaged and aging skin without destroying the epidermis.31,32 Irregular pigmentation and telangiectasia can be treated with intense pulsed light sources (IPL), 532 nm potassium-titanyl-phosphate lasers (KTP), and high-dose 585/595 nm pulsed dye lasers (PDL)33. Wrinkle reduction and skin tightening through thermal injury to the dermis (photothermolysis) can be achieved by other IPL sources (ie, low-dose 589/595 nm PDLs, & nm neodymium:yttrium-aluminum-garnet lasers, (Nd:YAG) nm diode lasers, and nm erbium fiber lasers).33
LED which is a novel light source for non-thermal, non-ablative skin rejuvenation has been shown to be effective for improving wrinkles and skin laxity (Figure 3).3440 It is not a new phenomenon since the first reports of LLLT effects on increased collagen go back to . Studies by Abergel et al. and Yu et al. reported an increase in production of pro-collagen, collagen, basic fibroblast growth factors (bFGF) and proliferation of fibroblasts after exposure to low-energy laser irradiation in vitro and in vivo animal models (Figure 4).41,42 Furthermore, LLLT was already known to increase microcirculation, vascular perfusion in the skin, alter platelet-derived growth factor (PDGF), transforming growth factor (TGF-β1) and inhibit apoptosis (Figure 4).1,43,44 Lee et al. investigated the histologic and ultrastructural changes following a combination of 830 nm, 55 mW/cm2, 66 J/cm2 and 633 nm, 105 mW/cm2, 126 J/cm2 LED phototherapy and observed alteration in the status of MMPs and their tissue inhibitors (TIMPs).33 Furthermore, mRNA levels of IL-1β, TNF-α, ICAM-1, and connexin 43 (Cx43) were increased following LED phototherapy whereas IL-6 levels were decreased (Figure 4) 33. Finally, an increase in the amount of collagen was demonstrated in the post-treatment specimens 33. Pro-inflammatory cytokines IL-1β and TNF-α are thought to be recruited to heal the intentionally formed photothermally-mediated wounds associated with laser treatments, and this cascade of wound healing consequently contributes to new collagen synthesis.33 LED therapy may induce this wound healing process through non-thermal and atraumatic induction of a subclinical quasi-wound, even without any actual thermal damage which could cause complications as in some other laser treatments.33 TIMPs inhibit MMP activities, so another possible mechanism for the increased collagen could be through the induction of TIMPs (Figure 4). When these observations are put together, it is possible that increased production of IL-1β and TNF-α might have induced MMPs in the early response to LED therapy. This may clear the photodamaged collagen fragments to enable biosynthesis of new collagen fibers. Later on, an increase in the amount of TIMPs might protect the newly synthesized collagen from proteolytic degradation by MMPs.33 Furthermore, increased expression of Cx43 may possibly enhance cell-to-cell communication between dermal components, especially the fibroblasts, and enhance the cellular responses to the photobiostimulation effects from LED treatment, in order to produce new collagen in a larger area which even includes the non-irradiated regions.33 In a clinical study performed by Weiss et al., 300 patients received LED therapy (590 nm, 0.10 J/cm2) alone, and 600 patients received LED therapy in combination with a thermal-based photorejuvenation procedure. Among patients who received LED photorejuvenation alone, 90% reported that they observed a softening of skin texture and a reduction in roughness and fine lines ranging from a significant reduction to sometimes subtle changes.36 Moreover, patients receiving a thermal photorejuvenation laser with or without additional LED photomodulation (n = 152) reported a prominent reduction in post-treatment erythema and an overall impression of increased efficacy with the additional LED treatment.36,45 This reduction in post-treatment erythema could be attributed to anti-inflammatory effects of LLLT.40 Using different pulse sequence parameters, a multicenter clinical trial was conducted, with 90 patients receiving 8 LED treatments over 4 weeks.37,4648 The outcome of this study showed very favorable results, with over 90% of patients improving by at least one Fitzpatrick photoaging category and 65% of patients demonstrating global improvement in facial texture, fine lines, background erythema, and pigmentation. The results peaked at 4 to 6 months following completion of 8 treatments. Markedly increased collagen in the papillary dermis and reduced MMP-1 were common findings. Barolet et al.s study is also consistent with the previously mentioned studies. They used a 3-D model of tissue-engineered human reconstructed skin to investigate the potential of 660 nm, 50 mW/cm, 4 J/cm2 LED in modulating collagen and MMP-1 and results showed upregulation of collagen and down-regulation MMP-1 in vitro.40 A split-face, single-blinded clinical study was then carried out to assess the results of this light treatment on skin texture and appearance of individuals with aged/photoaged skin.40 Following 12 LED treatments, profilometry quantification demonstrated that while more than 90% of individuals had a reduction in rhytid depth and surface roughness, 87% of the individuals reported that they have experienced a reduction in the Fitzpatrick wrinkling severity score.40
Examples of LLLT devices in dermatology for home and clinical use.
Possible mechanism of actions for LLLTs effects on skin rejuvenation.
LLLT aids skin rejuvenation through increasing collagen production and decreasing collagen degradation. Increase in collagen production occurs by LLLTs increasing effects on PDGF and fibroblast production which happens through decreasing apoptosis, increasing vascular perfusion, bFGF and TGF-β. Decrease in IL-6, and increase in TIMPs which in turn reduce MMPs all aid in reduction of collagen degradation.
Pathogenesis of acne vulgaris has not yet been clarified, however current consensus is that it involves four main events: follicular hyperconification, increased sebum secretion effected by the androgenic hormone secretions, colonization of Propionibacterium acnes and inflammation.49 P. acnes plays a key role by acting on triglycerides and releasing its cytokines which in turn trigger inflammatory reactions and alter infundibular keratinization.49 Current treatments for acne vulgaris include topical and oral medications such as topical antibiotics, topical retinoids, benzoyl peroxide, alpha hydroxy acids, salicylic acid, or azaleic acid. In severe cases, systemic antibiotics such as tetracycline and doxycycline, oral retinoids, and some hormones are indicated.50 Medications work by counteracting microcomedone formation, sebum production, P. acnes, and inflammation.50 Despite many options that are available for treatment of acne vulgaris, many patients still respond inadequately to treatment or experience some adverse effects.
Phototherapy (light, lasers, and photodynamic therapy) has been proposed as an alternative therapeutic modality to treat acne vulgaris and was proposed to have less side effects compared to other treatment options.51 Exposure of sunlight was reported to be highly effective for treatment of acne with efficacy up to 70%.52 The sunlight decreases the androgenic hormones in the sebaceous gland, but the unwanted effect of exposure to UVA and UVB limits sunlight for the treatment of acne. Recently, phototherapy with visible light (mainly blue light, red light or combination of both) started being used in the treatment of acne (Figure 3).52 One mechanism of action of phototherapy for acne is through the absorption of light (specifically blue light) by porphyrins that have been produced by P. acnes as a part of its normal metabolism, and that act as endogenous photosensitizers. 49,53 This process causes a photochemical reaction and forms reactive free radicals and Singlet oxygen species which in turn lead to bacterial destruction (Figure 5).49,53 Red light is known to penetrate deeper in tissues when compared to blue light.50 It has been demonstrated that red light can affect the sebum secretion of sebaceous glands and change keratinocyte behavior.54 Furthermore, red light might also exert its effects by modulating cytokines from macrophages and other cells, which in turn could reduce inflammation.51,54
Illustration of acne treatment with red and blue light.
Red and blue light when used in combination have synergistic effects in treatment of acne. P. acnes synthesizes and stores a large amount of porphyrins. Once the porphyrin is exposed to visible light (specifically blue light) it becomes chemically active and transfers to an excited state, resulting in formation of reactive free radicals and singlet oxygen which in turn causes membrane damage in P. acnes 49,53. Red light is proposed to exert its effects through reducing the inflammatory process 51,54.
Several studies reported that LLLT in the red to near infrared spectral range (630 nm) and nonthermal power (less than 200 mW) alone or in combination with other treatment modalities (mainly blue light), is effective for treatment of acne vulgaris.17,49,52,54,55 One of these studies demonstrated significant reduction in active acne lesions after 12 sessions of treatment using 630-nm red spectrum LLLT with a fluence of 12 J/cm2 twice a week for 12 sessions in conjunction with 2% topical clindamycin; however the same study showed no significant effects when a 890 nm laser was used.50 A few studies also showed that the combination of blue light and red light have synergistic effects in acne treatment.49,5456 It is proposed that synergistic effects of mixed light is due to synergy between the anti-bacterial and anti-inflammatory effect of blue and red light respectively (Figure 5).49,56 It is also worth mentioning that in most studies improvement in inflammatory lesions were higher than the improvement in comedones.49,56
It is widely accepted that the UV range (< 400 nm) exposure is responsible for almost all damaging photo-induced effects on human skin.5759 Some proposed mechanisms for UV induced skin damage are collagen breakdown, formation of free radicals, inhibition of DNA repair, and inhibition of the immune system.5759 Existing solutions to prevent UV induced damaging effects are based on minimizing the amount of UV irradiation that reaches the skin, which is achieved by either avoidance of sun exposure or by use of sunscreens. However sometimes sun avoidance might be hard to implement, especially for the people involved in outdoor occupations or leisure activities. On the other hand, the photoprotective efficacy of topical sunscreens have their own limitations as well, which include decreased efficacy following water exposure or perspiration, spectral limitations, possible toxic effects of nanoparticles that are contained by most sunscreens,60 user allergies, and compliance.
It has recently been suggested that infrared (IR) exposure might have protective effects against UV-induced skin damage mainly by triggering protective/repair responses to UV irradiation. In the natural environment, visible and IR solar wavelengths predominate in the morning and UVB and UVA are maximal around noon which suggest that mammalians already possess a natural mechanism which, in reaction to morning IR radiation, prepares the skin for upcoming potentially damaging UV radiation at noon.61 However, opposing views also exist, such as Krutmanns study demonstrating IR-induced disturbance of the electron flow of the mitochondrial electron transport chain which leads to inadequate energy production in dermal fibroblasts.62 Schroeders report is another example stating that IR alters the collagen equilibrium of the dermal extracellular matrix by leading to an increased expression of the collagen-degrading enzyme MMP-1, and by decreasing the de novo synthesis of the collagen itself.59 As previously mentioned, the same light source may have opposite effects on the same tissue depending on the parameters used and these conflicting views are probably due to the biphasic effects of light.18,19
Menezes et al. demonstrated that non-coherent near infrared radiation (NIR) (7002,000 nm) generated a strong cellular defense against solar UV cytotoxicity in the absence of rising skin temperature and it was assumed to be a long-lasting (at least 24 hours) and cumulative phenomenon.63 Following this study, Frank et al. proposed that IR irradiation prepares cells to resist UVB-induced damage by affecting the mitochondrial apoptotic pathway.64 IR pre-irradiation of human fibroblasts was shown to inhibit UVB activation of caspase-9 and -3, partially release of cytochrome c and Smac/Diablo, decrease pro-apoptotic (ie, Bax) and increase anti-apoptotic proteins (ie, Bcl-2 or Bcl-xL).64 The results suggested that IR inhibited UVB-induced apoptosis by modulating the Bcl2/Bax balance, pointing to a role of p53, a sensor of gene integrity involved in cell apoptosis and repair mechanisms. In a further study, Frank et al. studied more specifically the role of the p53 cell signaling pathway in the prevention of UVB toxicity.64 The response to IR irradiation was shown to be p53 dependent which further suggests that IR irradiation prepares cells to resist and/or to repair further UVB-induced DNA damage. Finally, the IR induction of defense mechanisms was supported by Applegate et al. who reported that the protective protein, ferritin, normally involved in skin repair (scavenger of Fe2+ otherwise available for oxidative reactions) was induced by IR radiation.65
In an in vitro study, it was reported that an increase dermal fibroblast procollagen secretion reduces metalloproteinases (MMP) or collagenase production following non-thermal non-coherent deep red visible LED exposures (660 nm, sequential pulsing mode).40 These results correlated with significant clinical improvement of rhytids in vivo.40 In a subsequent in vivo pilot study, effect of this wavelength in 3 healthy subjects using a minimal erythemal dose (MED) method adapted from sunscreen SPF determination has been investigated.61 The results showed that LED therapy was effective, achieving a significant response in the reduction of the erythema induced by UVB.61 Following this pilot study a further investigation has been performed to find out in vivo aspects of this phenomenon. Effects of non-thermal, non-coherent 660 nm LED pulsed treatments in providing enhanced skin resistance prior to upcoming UV damage was investigated in a group of subjects with normal fair skin and patients presenting polymorphous light eruption (PLE). Results suggested that LED based therapy prior to UV exposure provided significant dose-related protection against UVB induced erythema. A significant reduction in UVB induced erythema reaction was observed in at least one occasion in 85% of subjects as well as in the patients suffering from PLE. Furthermore, a sun protection factor SPF-15-like effect and a reduction in post-inflammatory hyperpigmentation were observed. An in vitro study by Yu et al. revealed that HeNe laser irradiation stimulated an increase in nerve growth factor (NGF) release from cultured keratinocytes and its gene expression.66 NGF is a major paracrine maintenance factor for melanocyte survival in skin.67 It was shown that NGF can protect melanocytes from UV-induced apoptosis by upregulating BCL-2 levels in the cells.68 Therefore, an increase in NGF production induced by HeNe laser treatment may provide another explanation for the photoprotective effects of LLLT.
One of the most common virus infections is caused by herpes simplex virus (HSV). HSV is chronic and lasts ones entire life. The exposure of the host to several kinds of physical or emotional stresses such as fever, exposure to UV light, and immune suppression causes virus reactivation and migration through sensory nerves to skin and mucosa, localizing particularly on the basal epithelium of the lips and the perioral area.69 Up to 60% of sufferers will experience a prodromic stage, after which the lesions develop through stages of erythema, papule, vesicle, ulcer and crust, until healing is achieved. It is accompanied by pain, burning, itching, or tingling at the site where the blisters form. Immune responses to HSV infection involve: macrophages, Langerhans cells, natural killer cells, lymphocyte-mediated delayed-type hypersensitivity, and cytotoxicity.70
While several anti-viral drugs such as acyclovir and valacyclovir are used to control recurrent herpes outbreaks, only limited reduction in the lesions healing time has been observed.69 Furthermore, development of drug-resistant HSV strains is of increasing significance especially in immunocompromised patients.70 Therefore, new therapy modalities that can shorten the recurrent episodes and cause prominent reduction of related pain and inflammation are necessary.
LLLT has been suggested as an alternative to current medications for accelerated healing, reducing symptoms and influencing the length of the recurrence period.69,71,72 Among 50 patients with recurrent perioral herpes simplex infection (at least once per month for more than 6 months), when LLLT (690 nm, 80 mW/cm2, 48 J/cm2) was applied daily for 2 weeks during recurrence-free periods it was shown to decrease the frequency of herpes labialis episodes.73 In another study with similar irradiation parameters (647 nm, 50 mW/cm2, 4.5 J/cm2), investigators achieved a significant prolongation of remission intervals from 30 to 73 days in patients with recurrent herpes simplex infection.74 Interestingly, patients with labial herpes infection showed better results than those with genital infection. However, irradiation did not effect established HSV latency in a murine model.75
Even though mechanism of action is still not clear, an indirect effect of LLLT on cellular and humoral components of the immune system involved in antiviral responses rather than a direct virus-inactivating effect was proposed.76 Inoue et al. investigated tuberculin reactions at the bilateral sites of the backs of sensitized guinea pigs. They applied a single low-power laser irradiation dose at a fluence of 3.6 J per cm2on one side and compared it to contralateral non-irradiated sites.77 Interestingly, following irradiation, tuberculin reaction was suppressed not only at the irradiated site but also at the contralateral nonirradiated site. It is worth to note that this phenomenon was observed when mononuclear cells were dominant in the perivascular cellular infiltration. Based on their results, they have suggested a possible systemic inhibitory effect of LLLT on delayed hypersensitivity reactions.77 Activation and proliferation of lymphocytes7881 and macrophages82 as well as the synthesis and expression of cytokines83,84 following low intensities of red and NIR light have been reported by several investigators. The question of whether these effects of LLLT have any influence on HSV infection remains to be determined.
Vitiligo is an acquired pigmentary disorder characterized by depigmentation of the skin and hair. The underlying mechanism of how the functional melanocytes disappear from the involved skin is still under investigation. However, findings suggest that regardless of the pathogenetic mechanism involved, keratinocytes, fibroblasts, melanoblasts and melanocytes may all be involved in both the depigmentation and also the repigmentation processes of vitiligo.66,8589 Therefore, stimulation of these epidermal and dermal cells may be a possible treatment option. Due to the obscure pathogenesis of the disease, treatment of vitiligo has generally been unsatisfactory. Current existing therapies that induce varying degrees of repigmentation in patients with vitiligo are topical corticosteroids, phototherapy, and photochemotherapy (PUVA).89 In , a group of investigators found that low energy laser irradiation had effects on defective biosynthesis of catecholamine in certain dermatological conditions including scleroderma and vitiligo.90,91 Later on, one of the investigators from the same group reported that after 68 months of treating 18 vitiglio patients with low-energy HeNe laser (632 nm, 25 mW/cm2 ) therapy, marked repigmentation was observed in 64% of the patients and some follicular repigmentation was observed in the remaining 34%.91 Since then, LLLT has been suggested as an alternative effective treatment option for patients with vitiligo.66,88,89
Segmental-type vitiligo is associated with a dysfunction of the sympathetic nerves in the affected skin and it is relatively resistant to conventional therapies.66 Based on the previous reports stating that HeNe laser irradiation leads to improvement in nerve injury9294 and LLLT induces repigmentation responses,95,96 it was proposed that the HeNe laser might be a potential treatment modality for treatment of segmental type vitiligo. 66 When the HeNe laser light was administered locally (3 J/cm2, 1.0 mW, 632.8 nm), marked perilesional and perifollicular repigmentation (> 50%) was observed in 60% of patients with successive treatments. Both NGF and bFGF stimulate melanocyte migration and deficiencies of these mediators may participate in the development of vitiligo.86,97,98 In the same study, when cultured keratinocytes and fibroblasts were irradiated with 0.51.5 J per cm2 HeNe laser, significant increase in bFGF release both from keratinocytes and fibroblasts as well as a significant increase in NGF release from keratinocytes was reported. 66 Additionally, the medium from HeNe laser irradiated keratinocytes stimulated [3H]thymidine uptake and proliferation of cultured melanocytes. Another study by Lan et al. demonstrated that the HeNe laser (632.8 nm, 1 J/cm2 and 10 mW) stimulates melanocyte proliferation through enhanced α2β1 integrin expression88 and induces melanocyte growth through upregulation of the expression of phosphorylated cyclic-AMP response element binding protein (CREB) which is an important regulator of melanocyte growth.88 ECM molecules are also important elements of the pigmentation process due to their regulatory roles for physiological functions of pigment cells including morphology, migration, tyrosinase activity and proliferation.99101 Type IV collagen is present in the basement membrane and is known to have an intricate relationship with melanocytes in the epidermis such as increasing melanocyte mobility.89 Following, HeNe irradiation, the attachment of melanocytes to type IV collagen was found to be significantly enhanced which also indicated modulation of melanocyte physiological function by HeNe laser irradiation.88 Furthermore, among various ECM proteins found in the dermis, fibronectin was shown to have significant effects on both differentiation and migration of cultured melanoblasts and melanocytes.102,103 In , Gibson et al. demonstrated that the physical distribution of fibronectin in vivo was closely associated with the migration path undertaken by melanoblasts during the repigmentation process of vitiligo.104 Based on Lan at al.s findings, an immature melanoblast cell line (NCCmelb4) showed significant decrease in the attachment to fibronectin following HeNe laser treatment while the attachment of a more differentiated melanoblast cell line (NCCmelan5) to fibronectin increased about 20% following 1 J/cm2, 10 mW HeNe laser treatment.89 Lastly, expression of integrin a5b1 which mediate locomotion of pigment cells was found to be enhanced on NCCmelb4 cells.89
Most studies carried out for vitiligo show the stimulatory effects of LLLT on pigmentation; however in a previously mentioned study, while testing effects of blue and red laser for acne treatment, an interesting and unexpected result was found for the first time.49 Combining both blue (415 +5 nm, irradiance 40 mW/cm2, 48 J/cm2 ) and red (633 +- 6 nm, 80 mW/cm2, 96 J/cm2 ) light produced an overall decrease in the melanin level. Instrumental measurement results showed that melanin level increased by 6.7 (the median of differences between the melanin level before and after one treatment session) after blue light irradiation without a statistical significance (P > .1), whereas it decreased by 15.5 with statistical significance (P < .005) after red light irradiation. This finding may have some relationship with the lasers brightening effect of the skin tone, which 14 out of 24 patients spontaneously reported after the treatment period. However as of today, no other studies investigated or reported similar decrease in melanin levels following red light irradiation. Considering that different parameters are used for vitiligo and acne treatment, different effects of red light on the same tissue might be due to the biphasic effects of LLLT.18,19
Hypertrophic scars and keloids are benign skin tumors that usually form following surgery, trauma, or acne and are difficult to eradicate. Fibroblastic proliferation and excess collagen deposits are the 2 main characteristics105 and imbalance between rates of collagen biosynthesis and degradation superimposed on the individuals genetic predisposition have been implicated in their pathogenesis. A wide range of surgical (eg, cryotherapy, excision), non-surgical (e.g., pharmacological, mechanical pressure, silicone gel dressings), and laser therapies (CO2, pulsed dye, fractional ablative, and non-ablative lasers) have been tested with variable success, however until now, an optimal treatment of these lesions remains to be found.106108 It has recently been proposed that poor regulation of interleukin (IL)-6 signaling pathways and transforming growth factor beta-I (TGF-βI) expression have a significant role in this process and thus inhibition of the IL-6 pathway and/or TGF-βI could be a potential therapeutic target.106,107,109111 Based on the reports demonstrating the effects of LLLT on decreasing IL-6 mRNA levels,33 modulation of PDGF, TGF-β, interleukins such as IL-13 and IL- 15, MMPs, which are all also associated with abnormal wound healing,112,113 it was proposed to be an alternative therapy to existing treatment options. The use of LLLT as a prophylactic method to alter the wound healing process to avoid or attenuate the formation of hypertrophic scars or keloids has been investigated by Barolet and Boucher in 3 cases studies, where following scar revision by surgery or CO2 laser ablation on bilateral areas, a single scar was treated daily by the patient at home with NIR - LED 805 nm at 30 mW/cm2 and 27 J/cm2.112 The first patient had pre-auricular linear keloids bilaterally post-face lift procedure and surgical scar revision/excision had been performed. The second patient had hypertrophic scars on the chest bilaterally post-acne when the CO2 laser was used for resurfacing. The third patient had hypertrophic scars on the back bilaterally post-excision and again the CO2 laser was used for resurfacing. As a result, significant improvements on the NIR-LED treated vs the control scar were seen in all efficacy measures and moreover no significant treatment-related adverse effects were reported.112
In a clinical study by Weiss et al. 10 patients received LED treatment (590 nm) for acute sunburn using a once-or twice-daily treatment regimen for 3 days, treating only half of the affected anatomic area.36 Decreased symptoms of burning, redness, swelling, and peeling were reported. One patient received LED treatment twice daily for 3 days only on half of his back, and other half was left untreated.36 When compared with the untreated side, decreased MMP-1 was demonstrated on the LED-treated side through immunofluorescence staining. Moreover, RT-PCR gene expression analysis showed a significant decrease in MMP-1 gene expression on the LED-treated side at both 4 and 24 hours postUV injury compared with the untreated side. Other significant changes were also noted with LED treatment related to inflammation and dermal matrix composition 4 days postultraviolet (UV) exposure.36
One of the main complications of receiving laser treatment is burns which may be devastating for the patient. LED was suggested as a treatment modality for facilitating faster healing. A group of 9 patients who had a variety of second-degree burns from nonablative laser devices were given LED therapy once a day for 1 week and according to both the patient and the physician, healing occurred 50% faster.36 Also the same investigators conducted a pilot study, where one forearm was injured by a CO2 laser using a computer pattern generator to deliver the identical treatment to both test sites. Both sites received daily dressing changes using a non-stick dressing and Polysporin ointment, but one site also received additional LED treatment.36 As a result, when compared to the untreated control site, accelerated reepithelialization was observed in the LED-treated site 36.
More recently LLLT has been considered for treatment of plaque psoriasis. A recent preliminary study investigated the efficacy of a combination of 830 nm (near infrared) and 630 nm (visible red light) to treat recalcitrant psoriasis using LED irradiation. All patients with psoriasis resistant to conventional therapy were enrolled and were treated sequentially with 830 nm and 630 nm wavelengths in 2 20-min sessions with 48 hours between session for 4 or 5 weeks. The results showed no adverse side effects and a resolution of psoriasis.114 The limitation of this study was the small number of patients enrolled, however the results observed encourage future investigations for use of LLLT in treating psoriasis.
LLLT appears to have a wide range of applications of use in dermatology, especially in indications where stimulation of healing, reduction of inflammation, reduction of cell death and skin rejuvenation are required. The application of LLLT to disorders of pigmentation may work both ways by producing both repigmentation of vitiligo, and depigmentation of hyperpigmented lesions depending on the dosimetric parameters. The introduction of LED array-based devices has simplified the application to large areas of skin. There is no agreement as yet on several important parameters particularly whether red, NIR, or a combination of both wavelengths is optimal for any particular application. There is a credibility gap that needs to be overcome before LLLT is routinely applied in every dermatologists office.
This work was supported by the US NIH (R01AI to MRH)
Conflict of Interest Disclosures: The authors have completed and submitted the ICMJE Form for Disclosure for Potential Conflicts of Interest and none were reported. Dr Gupta has received a grant from Boyscast Fellowship, Rolo-11, in India. All other authors have nothing to disclose.
Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Do you remember when cosmetic lasers were first introduced a couple of decades ago? The idea of zapping away age spots or never having to shave your legs or bikini line again was exciting until you had it done. Lasers of the past were painful, required dozens of sessions, and didnt offer satisfactory results but not in .
Nowadays, you have more options, such as IPL treatments, which are much less painful and much more advanced. However, the surge in these treatments has resulted in many at-home devices claiming to match up to professional treatments.
In this article, we will explain why you should reconsider purchasing an at-home laser device and how professional treatments are far superior. We will also discuss what an IPL treatment is, everything it can be used for, and how it differs from a standard laser treatment. Lets dive in!
IPL stands for intense pulsed light. Intense pulsed light treatment, also called IPL therapy or a photofacial, is a cutting-edge cosmetic procedure that uses a unique type of light and delivery method to penetrate the skins layers and tackle a range of skin issues.
While IPL is often grouped in the laser category and is often referred to as a laser treatment, IPL treatment isnt a traditional laser treatment. IPL operates by employing bursts of gentle yet powerful, broad-spectrum lightsort of like a photo flash (hence the name photo facial). In comparison, a regular laser focuses on one wavelength of light directed at your skin.
During an IPL laser treatment session, a handheld device is gently moved over the treatment area. Most describe the feeling as a slight sting or a rubber band lightly hitting the skin. The targeted regions absorb the energy from the light pulses, causing them to break down and gradually disappear through your bodys natural healing process. You might experience some redness and swelling following your session, but you can resume most activities immediately.
For some skin issues, such as broken blood vessels, results are noticeable as soon as the treatment ends. While other skin concerns, such as brown spots, might take a couple of weeks to reveal results. Skin discolorations, such as age or sun spots, become darker and flake off before revealing your improved skin.
For more information on IPL treatment, read FAQs: IPL Facial Treatment,
Both IPL and traditional laser treatments utilize light energy to address various skin issues and unwanted hair growth. But thats pretty much where their similarities end.
IPL isnt technically a laser treatment; its non-laser high-intensity light therapy. A laser is very strong and spotlights a single, focused beam of light on a specific spot. IPL is weaker and unfocused. Its more like a camera flash that spreads a broad spectrum of light with multiple wavelengths out over a large areaexactly why IPL is so great for treating skin.
So, while traditional lasers and IPL devices both use light, IPL uses completely different technology to deliver the light source.
If you are looking for more details, kindly visit Home Laser Therapy for Better Health.
Another difference is that IPL tends to be much less painful than traditional laser treatments, with most patients reporting only mild discomfort during the procedure. Additionally, IPL treatments typically have minimal downtime compared to traditional lasers, allowing patients to resume their daily activities immediately after the procedure.
While both a traditional laser and IPL can treat a wide range of skin concerns such as uneven skin tone, texture issues, and scars and are great for hair removal, IPL is the gentler, more advanced, modern choice.
The versatility and effectiveness of IPL have made it one of the most sought-after in-office cosmetic treatments for anyone hoping to improve the appearance and health of their skin or get rid of unwanted hair.
Here are some of the most common uses for IPL treatment:
IPL treatment can help reduce wrinkles and improve skin texture by stimulating collagen production. As collagen levels increase, skin becomes firmer and smoother while irregularities like fine lines and large pores diminish.
IPL treatment effectively improves the appearance of scars, such as acne and surgical scars, by triggering collagen remodeling and rejuvenating the skin. By stimulating collagen production, IPL helps fill in and soften the scar tissue, resulting in a smoother skin texture.
IPL therapy can reduce acne breakouts and inflammation by targeting acne-causing bacteria and reducing sebum production. This can result in clearer skin with fewer acne breakouts and a more even complexion.
If you have broken blood vessels on your face or legs, IPL treatment can effectively diminish their appearance. By targeting hemoglobin in the blood vessels, IPL causes them to collapse and fade, resulting in a reduction in visible veins and an overall improvement in skin appearance.
Skin discolorations are often caused by an overproduction or irregular distribution of melanin in the skin. This can result from prolonged sun exposure, hormonal changes, aging, or genetics. During IPL treatment, the targeted bursts of intense pulsed light work to break down the excess melanin in these areas, gradually fading pigmented lesions and promoting a more even skin tone.
IPL works to lessen redness and symptoms of rosacea by targeting the blood vessels responsible for the visible redness. The intense pulsed light energy heats the targeted blood vessels, causing them to constrict and gradually fade over time. Additionally, IPL stimulates collagen production, which can help strengthen the skin and reduce redness associated with rosacea.
Stretch marks, or striae, are a common concern for many people. They often appear as streaks or lines on the skin. IPL treatment can be effective in reducing the appearance of stretch marks by stimulating collagen production, which helps to improve the elasticity and texture of the skin. Over time, the skin undergoes natural healing processes, resulting in smoother and more even-toned skin.
Shaving is a hassle, and waxing requires hair re-growth windows that dont always time out around important events. IPL effectively reduces hair growth in the treated areas, resulting in smoother skin and long-lasting hair reduction.
IPL hair removal works by emitting pulses of intense light energy that are absorbed by the melanin in the hair follicles. This process heats and damages the follicles, inhibiting their ability to regrow hair.
IPL treatments are highly sought after because they can address a variety of skin concerns in a quick office visit, offering effective, long-term results with minimal discomfort and downtime.
Here are some key advantages of IPL treatment over traditional lasers:
Lasers often have a bad reputation for being painful. IPL treatment is significantly less painful compared to other procedures like traditional laser treatments or waxing. In fact, most patients report only mild stinging discomfort during the procedure, making it a more comfortable option for hair removal and skin rejuvenation.
IPL treatment stands out for its ability to deliver longer-lasting results. Compared to other skin procedures, IPL treatments are more sustainable over time, reducing the need for frequent touch-ups or maintenance sessions.
One significant advantage of IPL treatment is its versatility. It can be customized to suit different skin tones and hair types, making it suitable for a wide range of people seeking hair removal or skin rejuvenation.
IPL is a non-invasive procedure that does not require incisions or anesthesia. This makes it a safer option for individuals who may not be suitable candidates for invasive procedures.
IPL treatments typically have minimal downtime compared to more invasive procedures like laser resurfacing or advanced chemical peels. Patients can usually resume their daily activities immediately after the procedure, with only mild redness or swelling that subsides quickly.
IPL treatments are relatively quick. Many clients even pop in on their lunch break. Small areas like the upper lip or underarms can be treated in just a few minutes. Even larger areas like the legs dont require lengthy office visits.
IPL treatment is often more cost-effective in the long run compared to other cosmetic procedures. While the upfront cost may be higher than other skin rejuvenation and hair removal methods, such as facials and waxing, the long-lasting results mean fewer maintenance treatments over time, saving money in the long term.
IPL can address multiple skin concerns simultaneously, including hair removal, pigmentation issues, vascular lesions, and signs of aging. This versatility allows patients to target multiple concerns in a single treatment session, saving time and effort.
Because IPL can cover larger areas of the skin in a single session, it is more time-efficient for patients seeking treatment for larger body areas. The broader spectrum of light used in IPL also means that it can be adjusted to target specific skin concerns more precisely, leading to more consistent and predictable results.
For more on the benefits of IPL treatment, click here.
With the growing demand for at-home skin and hair removal solutions, numerous laser devices have flooded the market, promising to deliver professional-quality results in the comfort of your own home at a price point less than a single professional treatment.
However, as the old adage goes, You get what you pay for. While at-home IPL devices may offer convenience and appear to offer cost savings, they lack the precision, power, and expertise of professional IPL treatments. Furthermore, they could be dangerous.
Here are some key differences between professional IPL treatments and at-home laser devices:
Professional IPL treatment uses very advanced technology that is significantly more advanced than at-home devices, allowing for more precise targeting of specific skin concerns and hair removal.
At-home devices do not have this patented technology. They operate at lower intensities and require significant time for treatment. Consequently, results may appear inconsistent and patchy due to irregular treatment patterns.
Thanks to the expertise of trained professionals and the use of advanced technology, professional IPL treatments yield more visible, consistent and predictable results than at-home devices.
Users of at-home devices might see a slight decrease in unwanted hair and a minor improvement in skin issues. However, it takes months of consistent use, and once discontinued, the problems usually come back with no assurance of sustained results.
There really isnt a comparison when it comes to results. Professional IPL devices provide noticeable results with limited sessions, whereas home devices might provide minor improvements after months of consistent, ongoing use.
If you want to use a home device, get ready to spend a lot of your time. You must use the device numerous times a week, for months, before noticing even minor improvements. Then, you must continue using the device consistently to maintain results.
Professional IPL treatments are much more powerful and cover larger areas of the skin, providing obvious results in limited sessions with fewer maintenance visits.
When considering using a laser or light therapy on your skin, its a bad idea to attempt to do it yourself or allow someone who isnt trained to use cosmetic lasers. You could harm your skin if you arent careful.
Clinics and medical spas adhere to strict safety protocols to ensure the safety and comfort of patients during IPL treatments, minimizing the risk of adverse effects or complications.
Professional IPL treatments are administered by trained and experienced technicians who understand how to customize treatments for each individuals skin type and concerns. For example, those with darker skin will require different protocols than those with fair skin.
If you attempt IPL at home, you could end up causing damage to your skin, such as burns, blistering, or hyperpigmentation. Additionally, some areas, such as the back of the legs, the back of the neck, and the back, are hard to reach and better treated by a professional.
At-home devices do not offer the same features as professional devices. Professional IPL devices can tailor IPL treatments to address specific skin concerns and adjust parameters such as light intensity and pulse duration to optimize results while minimizing side effects.
At-home laser devices have limitations in terms of safety, efficacy, and customization. If you want optimal results and peace of mind, professional IPL facial laser treatments remain the gold standard.
Sure, you could spend less money on a home laser device, but you will not get the same results, and you could hurt yourself. So, if we are being blunt, most at-home face laser devices are a waste of money and could be dangerous if not used properly.
Bottom line home devices will end up like many gadgets youve purchased, collecting dust on a shelf.
Professional IPL laser treatments are highly safe when performed by licensed and experienced professionals. Clinics adhere to strict safety protocols, ensuring that treatments are administered correctly and tailored to each individuals unique skin type and concerns. Additionally, many professional IPL devices have received FDA approval, further confirming their safety and efficacy.
In terms of the safety of at home laser devices, we do not believe most are safe and would not recommend them. While at-home devices may seem convenient, they pose significant risks when used improperly. Misapplication or incorrect settings could result in adverse effects such as burns, blistering, hyperpigmentation, or scarring.
The cost of a professional IPL laser treatment can vary depending on several factors, including the area being treated, the severity of the condition, and the number of sessions required to achieve optimal results.
For example, targeting a single visible facial vein may cost less than addressing multiple spider veins on the legs. One light age spot might be resolved in one session, while darker spots might require a few treatments.
Since IPL treatments are often customized to each individuals needs, providing a precise cost without a consultation is challenging. However, clinics typically offer laser packages to accommodate various treatment goals.
If you want to know exactly how much your IPL laser treatment will cost, you should book a complimentary consultation with a skincare professional to receive an accurate estimate based on your specific concerns and desired outcomes.
The number of IPL laser treatments required varies depending on several factors, including the specific skin concern being addressed, its severity, and individual skin characteristics. While some patients may see noticeable improvement after just one session, most will require multiple treatments spaced several weeks apart to achieve optimal results.
For skin rejuvenation or pigmentation issues, a series of treatments may be needed to achieve desired outcomes. Similarly, for hair removal, multiple sessions are necessary to target hair follicles at different stages of growth.
During a consultation, a skincare professional will assess the patients skin and develop a personalized treatment plan outlining the recommended number of sessions and expected timeline for results.
IPL is preferred over a standard laser due to its versatility, efficiency, and ability to treat a wide range of skin concerns in a single session. This type of technology is far superior to a standard laser or any at-home device, but it isnt available everywhere.
At Garza Plastic Surgery, we proudly offer Lumecca IPL facial laser treatments as a quick and easy way to revitalize your skin. The Lumecca IPL machine boasts remarkable power, delivering up to three times more energy than others on the market. With its larger spot size and high pulse repetition rate, the Lumecca device offers the advantage of reduced treatment time, allowing for quicker and more efficient sessions.
Whether you want to minimize skin damage on your face, hands, or head caused by the sun, clear up rosacea, improve the appearance and texture of scars, or eliminate broken blood vessels and spider veins, IPL can help in only a few treatments.
Book your complimentary consultation today to discover if an IPL facial laser treatment is right for you! You can also click here to learn how this trademarked pulsed light technology works and what to expect before, during, and after treatment.
If you want to learn more, please visit our website Low Level Laser Therapy.