Clinical application of low reactive level laser therapy (LLLT) for atopic dermatitis

Effect of low-level laser intervention on dermatitis symptoms and cytokine changes in DNCB-induced atopy mouse model: A randomized controlled trial

The incidence of atopic dermatitis (AD) has recently increased due to various factors. Its prevalence is higher among children and teenagers than in other age groups. Numerous methods to treat AD are available, including light ray therapy, which has been proposed as an alternative therapy for the treatment of AD. The present study aimed to evaluate the curative mechanism and optimal energy level of energy irradiation from a low-level laser (LLL) toward AD. AD was induced in BALB/c mice with dinitrochlorobenzene (DNCB) solution. The mice were divided into six groups, including one normal control (n=8), one AD control (n=10) and four AD experimental groups with LLL irradiation at 2 J/cm² (n=10), 4 J/cm² (n=10), 6 J/cm² (n=9) and 8 J/cm² (n=10). Following AD induction, an LLL was applied to the four AD experimental groups for 2, 4, 6, and 8 min, for two weeks (14 times in total) at a wavelength of 650 nm and an output of 50 mW. The effects of irradiation on AD were evaluated using a scratch test, a clinical skin severity test, immunoglobulin-E (IgE) analysis and measurements of numerous cytokine levels, including interleukin (IL)-4, IL-6, tumor necrosis factor (TNF)-α, and interferon-γ (IFN-γ), tissue thickness and mast cell count. The results demonstrated that serum IgE level in all irradiated groups was significantly decreased compared with that of the AD control group, and IL-4 level was significantly decreased in all irradiated groups apart from the 8 J/cm² LLL irradiated group. IL-6 and TNF-α levels were also significantly decreased in all irradiated groups. The results from histological analysis revealed diminished epidermal thickness and mast cell counts in irradiated mice compared with those mice in the AD control group. In summary, these findings suggested that LLL irradiation may alleviate symptoms of AD and may be useful for restoring cytokines levels and tissues features to normal levels.

Is low-level laser therapy useful as an adjunctive treatment for canine acral lick dermatitis? A randomized, double-blinded, sham-controlled study

BACKGROUND

Conventional therapy for canine acral lick dermatitis (ALD) consists of systemic antibiotics and anti-anxiety medications. Low-level laser therapy (LLLT) is a noninvasive therapy used to treat inflammatory and painful conditions.

HYPOTHESIS/OBJECTIVES

The primary objective was to determine whether LLLT with conventional therapy would be beneficial as an adjunct treatment for ALD. We hypothesized that LLLT and conventional therapy combined would result in a greater reduction in licking Visual Analog Score (LVAS) compared to conventional therapy alone. Secondary objectives were to assess change in lesion/ulcer size, thickness and hair growth.

ANIMALS

Thirteen dogs with a skin lesion consistent with ALD.

METHODS AND MATERIALS

Dogs were randomly assigned to two groups. All dogs received systemic antibiotics and trazodone. The treatment group (TG) received LLLT by laser (130 mW, 2 min) with blue and red light-emitting diodes (LEDs), while the control group (CG) had sham therapy (laser/LEDs off). Treatments were administered three times weekly for two weeks, then twice weekly for two weeks for a total of 10 visits. Descriptive statistics were performed (mean, median); primary and secondary objectives were assessed with nonparametric ANOVA (Kruskal-Wallis test), with significance set at P < 0.05.

RESULTS

Thirteen dogs (six CG, seven TG) were enrolled. There were no significant differences in median LVAS, lesion/ulcer size or thickness of the ALD lesion between TG and CG. There was a significantly greater increase (24%) in hair growth in TG (P = 0.0081) compared to CG.

CONCLUSIONS AND CLINICAL RELEVANCE

Treatment of ALD requires multimodal therapy. Although combining LLLT with conventional therapy did not result in a significantly greater reduction in LVAS, there was a significant increase in hair growth compared to conventional therapy alone.

Advances in phototherapy for psoriasis and atopic dermatitis

Introduction: Phototherapy has long been used for the treatment of inflammatory skin diseases, such as psoriasis and atopic dermatitis. The most frequent treatment approach utilizes ultraviolet (UV) light, however, recently, different lasers and low-level light therapies (LLLT) emitting wavelengths in the spectrum of the visible light have also been tried for the treatment of inflammatory skin diseases with variable success.Areas covered: This review provides an update on the different forms of phototherapy used for the treatment of psoriasis and atopic dermatitis. The proposed mechanism of action of the different phototherapeutical approaches are covered, including the immunosuppressive effect of UV light, the anti-inflammatory effect of vascular lasers and the LLLT induced photobiomodulation. The clinical efficacy of the different treatment options is also discussed.Expert opinion: Based on the efficacy and safety, NB-UVB represents the gold standard for treating psoriasis and atopic dermatitis. The UVB excimer laser and excimer lamp might be the best option for clearing localized therapy-resistant lesions. Home UV phototherapy systems might promote treatment adherence and better compliance of the patients. Vascular lasers, IPLs and LLLT, however, can not currently be recommended for the treatment of inflammatory skin diseases because of the lack of well-controlled studies.

[LED lights in dermatology]

The use in dermatology of light-emitting diodes (LEDs) continues to be surrounded by controversy. This is due mainly to poor knowledge of the physicochemical phases of a wide range of devices that are difficult to compare to one another, and also to divergences between irrefutable published evidence either at the level of in vitro studies or at the cellular level, and discordant clinical results in a variety of different indications: rejuvenation, acne, wound healing, leg ulcers, and cutaneous inflammatory or autoimmune processes. Therapeutic LEDs can emit wavelengths ranging from the ultraviolet, through visible light, to the near infrared (247-1300 nm), but only certain bands have so far demonstrated any real value. We feel certain that if this article remains factual, then readers will have a different, or at least more nuanced, opinion concerning the use of such LED devices in dermatology.

Adjunctive 830 nm light-emitting diode therapy can improve the results following aesthetic procedures

BACKGROUND

Aggressive, or even minimally aggressive, aesthetic interventions are almost inevitably followed by such events as discomfort, erythema, edema and hematoma formation which could lengthen patient downtime and represent a major problem to the surgeon. Recently, low level light therapy with light-emitting diodes (LED-LLLT) at 830 nm has attracted attention in wound healing indications for its anti-inflammatory effects and control of erythema, edema and bruising.

RATIONALE

The wavelength of 830 nm offers deep penetration into living biological tissue, including bone. A new-generation of 830 nm LEDs, based on those developed in the NASA Space Medicine Laboratory, has enabled the construction of planar array-based LED-LLLT systems with clinically useful irradiances. Irradiation with 830 nm energy has been shown in vitro and in vivo to increase the action potential of epidermal and dermal cells significantly. The response of the inflammatory stage cells is enhanced both in terms of function and trophic factor release, and fibroblasts demonstrate superior collagenesis and elastinogenesis.

CONCLUSIONS

A growing body of clinical evidence is showing that applying 830 nm LED-LLLT as soon as possible post-procedure, both invasive and noninvasive, successfully hastens the resolution of sequelae associated with patient downtime in addition to significantly speeding up frank wound healing. This article reviews that evidence, and attempts to show that 830 nm LED-LLLT delivers swift resolution of postoperative sequelae, minimizes downtime and enhances patient satisfaction.

Clinical efficacy of low-level laser therapy on localized canine atopic dermatitis severity score and localized pruritic visual analog score in pedal pruritus due to canine atopic dermatitis

BACKGROUND

Canine atopic dermatitis is a genetically predisposed inflammatory skin disease often requiring multimodal treatment. There is a need to find further low-risk adjunctive therapies.

HYPOTHESIS/OBJECTIVES

To evaluate the localized effect of low-level laser therapy (LLLT) on the paws of dogs with atopic dermatitis using a localized canine atopic dermatitis severity score (LCADSS) and owner localized pruritic visual analog score (LPVAS) in comparison to treatment with a placebo.

ANIMALS

Thirty client-owned dogs with symmetrical pedal pruritus due to canine atopic dermatitis.

METHODS

Dogs were randomly assigned into two groups. In each group, one paw was treated with LLLT and one paw treated with a placebo laser (comparing either both fore- or hindpaws). Treatments were administered at 4 J/cm(2) (area from carpus/tarsus to distal aspect of digit 3) three times per week for the first 2 weeks and two times per week for the second 2 weeks. Scores were assessed for each paw at weeks 0, 2, 4 and 5.

RESULTS

There were no significant differences in LCADSS or LPVAS between LLLT and placebo treatments between weeks 0 and 5 (P = 0.0856 and 0.5017, respectively). However, LCADSS and LPVAS significantly decreased from week 0 at weeks 2, 4 and 5 in both LLLT and placebo groups (P < 0.0001 for all).

CONCLUSIONS AND CLINICAL IMPORTANCE

Low-level laser therapy is not an effective localized treatment for pedal pruritus in canine atopic dermatitis.

Guidelines of care for the management of atopic dermatitis: section 3. Management and treatment with phototherapy and systemic agents

Atopic dermatitis is a chronic, pruritic inflammatory dermatosis that affects up to 25% of children and 2% to 3% of adults. This guideline addresses important clinical questions that arise in atopic dermatitis management and care, providing recommendations based on the available evidence. In this third of 4 sections, treatment of atopic dermatitis with phototherapy and systemic immunomodulators, antimicrobials, and antihistamines is reviewed, including indications for use and the risk-benefit profile of each treatment option.

In vivo comparison of simple and double-fractionated low-level laser irradiation schemes on the healing of rat skin lesions

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 lambda = 635 nm and power = 15 mW. The exposure time was 600 s for the simple laser irradiation scheme and 300 s x 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: t exp 1 =600 s, power = 15 mW, lambda = 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: t exp 2 = t exp 1/2 = 300 s, power = 15 mW and lambda = 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.