The light revival: does phototherapy promote wound healing? A review

Immune-modulating properties of blue light do not influence reepithelization in vitro

Phototherapy is gaining more attention in the treatment of various diseases. Especially, blue light seems to be a promising approach for wound healing promotion due to its antimicrobial and immune-modulating properties. Despite this, there is only little research focusing on the immune-modulating properties of blue light and its possible effects on wound healing. Therefore, we investigated the effects of blue light irradiation on peripheral blood mononuclear cells (PBMC) and the influence on reepithelization in vitro. PBMCs were irradiated with DermoDyne® (DermoDyne HealthCare, Berlin, Germany) and effects on cell viability, cytokine expression, and scratch wound closure were evaluated afterwards. Irradiated cells showed a higher Interleukin-γ concentration while irradiation reduced resazurin concentration in a time-dependent manner. No differences in reepithelization were detectable when keratinocytes were treated with the supernatant of these blue light irradiated PBMCs. Blue light-mediated ex vivo stimulation of PBMCs does not cause faster reepithelization in an in vitro setting. Further research is needed to investigate the wound healing effects of phototherapy with blue light.

The influence of low- intensity laser irradiation versus hyperbaric oxygen therapy on transcutaneous oxygen tension in chronic diabetic foot ulcers: a controlled randomized trial

BACKGROUND AND OBJECTIVE

Evaluation of the stage and severity of the chronic diabetic foot ulcer (CDFU) is vital to increase the healing rate and to select the suitable treatment. We aim to assess the influence of low-intensity laser irradiation (LILI) and hyperbaric oxygenation therapy (HBOT) to accelerate the CDFU healing thru the transcutaneous oxygen tension (TcPO2) measurements.

MATERIALS AND METHODS

Seventy-five diabetic patients (type 2) of both genders, their ages ranged from 40-65 years with CDFUs (duration of ulcer < 6 weeks). All patients were randomly assigned into LILI, HBOT, and the control group. Measurement of TcPO2 using transcutaneous oximetry was performed for all patients once in the baseline and consequently in the second, fourth, and sixth- weeks duration. LILI utilized by a 33-diode cluster contact applicator with output power 1440 mW, energy density (fluency) was adjusted for 4 J/Cm2 at 10 kHz, and for 8 min per session, three times per week for a total of consecutive 6 weeks. HBOT was pressurized up to 2.5 ATA and patients delivered 100% oxygen for 60 min per session for 30 sessions. The Control group received conventional wound care only, twice daily, with saline and apply a new bandage after cleaning.

RESULTS

MANOVA revealed a statistically insignificant difference in the control group, while statistically significant improvement in both the LILI and HBOT groups. The intergroup comparisons showed an insignificant statistical difference in the pre-test, while highly statistically significant differences for the three post-measures in favor of HBOT and LILI groups. The percentage of improvement of the HBOT group was higher than LILI. Post-hoc test using the least significant difference (LSD) revealed statistically significant differences of HBOT in favor of the LILI group.

CONCLUSION

Both LILI and HBOT may be used as adjunctive methods to improve TcPO2 that accelerate healing in CDFUs. HBOT may be favorable in the improvement of TcPO2 than LILI.

Retrospective Matched Case-Control Study on the Use of CO2 Laser for the Treatment of Nonhealing Diabetic Foot Ulcers: The DULCIS-2 (Diabetic ULcer, CO2 Laser, and Infections) Study

PURPOSE

Infection, which is one of the possible complications of diabetic foot ulcers (DFUs), makes the treatment of ulcers challenging because of its negative impact on healing processes and the high prevalence of multiresistant germs. This study is aimed at verifying the effect of a surgical CO₂ laser (which reduces the bacterial load and allows a more accurate debridement), as compared with the traditional lancets, on the healing rate of DFU.

METHODS

The present case-control retrospective analysis was performed on patients with chronic (>6 months) DFU with Texas grade >1, treated with 80 W surgical CO₂ laser (DEKA SmartXide2 C80, El.En. Group) and compared with a matched sample of patients with similar characteristics, who were treated with a traditional surgical approach. The debridement was performed trying to achieve the complete removal of nonviable tissues. The principal endpoint was the proportion of patients healed at 6 months. All analyses were carried out with SPSS 25.0. The study protocol was approved by the local ethical committee.

RESULTS

This study included 118 patients (59 cases and 59 controls). At 6 months, the proportion of healing patients was 35% and 18% in cases and controls, respectively (P = .034). The corresponding figure at 1 year was 62% and 38% (P = .009), whereas no difference was observed at 1, 2, and 3 months. No serious adverse event was observed.

CONCLUSIONS

In this article, we show for the first time that CO₂ laser treatment, in comparison with traditional surgical approaches, can be associated with an increased healing rate in patients with DFU.

Therapeutic Efficacy of Home-Use Photobiomodulation Devices: A Systematic Literature Review

Objective: Perform systematic literature review on photobiomodulation (PBM) devices used at home for nonesthetic applications. Background: Home-use PBM devices have been marketed for cosmetic and therapeutic purposes. This is the first systematic literature review for nonesthetic applications. Methods: A systematic literature search was conducted for PBM devices self-applied at home at least thrice a week. Two independent reviewers screened the articles and extracted the data. Treatment dosage appropriateness was compared to the World Association for Laser Therapy (WALT) recommendations. The efficacy was evaluated according to the relevant primary end-point for the specific indication. Results: Eleven studies were suitable. Devices were applied for a range of indications, including pain, cognitive dysfunction, wound healing, diabetic macular edema, and postprocedural side effects, and were mostly based on near-infrared, pulsed light-emitting diodes with dosages within WALT recommendations. Regarding efficacy, studies reported mostly positive results. Conclusions: Home-use PBM devices appear to mediate effective, safe treatments in a variety of conditions that require frequent applications. Conclusive evaluation of their efficacy requires additional, randomized controlled studies.

Therapeutic Efficacy of Home-Use Photobiomodulation Devices: A Systematic Literature Review

OBJECTIVE

Perform systematic literature review on photobiomodulation (PBM) devices used at home for nonesthetic applications.

BACKGROUND

Home-use PBM devices have been marketed for cosmetic and therapeutic purposes. This is the first systematic literature review for nonesthetic applications.

METHODS

A systematic literature search was conducted for PBM devices self-applied at home at least thrice a week. Two independent reviewers screened the articles and extracted the data. Treatment dosage appropriateness was compared to the World Association for Laser Therapy (WALT) recommendations. The efficacy was evaluated according to the relevant primary end-point for the specific indication.

RESULTS

Eleven studies were suitable. Devices were applied for a range of indications, including pain, cognitive dysfunction, wound healing, diabetic macular edema, and postprocedural side effects, and were mostly based on near-infrared, pulsed light-emitting diodes with dosages within WALT recommendations. Regarding efficacy, studies reported mostly positive results.

CONCLUSIONS

Home-use PBM devices appear to mediate effective, safe treatments in a variety of conditions that require frequent applications. Conclusive evaluation of their efficacy requires additional, randomized controlled studies.

Electroactive biomaterials: Vehicles for controlled delivery of therapeutic agents for drug delivery and tissue regeneration

Electrical stimulation for delivery of biochemical agents such as genes, proteins and RNA molecules amongst others, holds great potential for controlled therapeutic delivery and in promoting tissue regeneration. Electroactive biomaterials have the capability of delivering these agents in a localized, controlled, responsive and efficient manner. These systems have also been combined for the delivery of both physical and biochemical cues and can be programmed to achieve enhanced effects on healing by establishing control over the microenvironment. This review focuses on current state-of-the-art research in electroactive-based materials towards the delivery of drugs and other therapeutic signalling agents for wound care treatment. Future directions and current challenges for developing effective electroactive approach based therapies for wound care are discussed.

A randomized, open-label, controlled trial to evaluate the antimicrobial and surgical effect of CO2 laser treatment in diabetic infected foot ulcers: DULCIS (diabetic ulcer, CO2 laser, and infections) study

AIM

Debridement of fibrin and necrotic tissue from the ulcer surface is an important component of the treatment of diabetic ulcers. A possible alternative to standard lancets is represented by CO₂ laser, which vaporizes necrotic tissues together with any pathogen. The present trial is aimed at verifying the effect of a CO₂ laser on bacterial load in the debridement of infected diabetic foot ulcers.

METHODS

In this open-label randomized controlled trial (NCT02677779), patients with diabetes and an infected foot ulcers were randomized to either CO₂ laser or traditional debridement.

RESULTS

The reduction (%) of bacterial load with CO₂ laser was significantly greater than in control group [-99.9 (-100.0; -90.0) vs. -50.0 (-96.0; -75.0), p = 0.049]. Similarly, a significantly greater reduction (%) of the fraction of ulcer area covered by fibrin was obtained in the intervention group [-84.1 (-95.0; -72.2) vs. -46.9 (-69.5; -40.8), p = 0.038].

CONCLUSIONS

Debridement of ulcers with CO₂ laser significantly reduces bacterial load and fibrin-covered areas, and could be of help in the treatment of diabetic foot ulcer.

Epitelização de enxertos cutâneos em feridas recentes de coelhos tratados com membrana amniótica canina e/ou laserterapia

RESUMO A enxertia cutânea é uma técnica cirúrgica simples e bastante útil para o reparo de feridas, principalmente aquelas onde existe dificuldade da aplicação do fechamento primário ou de outras técnicas reconstrutivas. Entretanto, para a sobrevivência do enxerto, é necessário que o leito da ferida esteja saudável e com presença de tecido de granulação exuberante. O objetivo do presente trabalho foi avaliar a aplicação da membrana amniótica e da laserterapia como potenciais estimulantes da cicatrização em enxertos aplicados em feridas sem tecido de granulação. Foram utilizados 42 coelhos, divididos em quatro grupos: grupo controle (GC), grupo membrana (GM), grupo laser (GL) e grupo membrana e laser (GML), submetidos a avaliações macro e microscópicas. Na avaliação macroscópica, foi possível notar que os pacientes dos grupos nos quais a membrana amniótica foi utilizada (GM e GML) apresentaram evidências associadas à acentuada reação inflamatória, à falha de integração do enxerto e à consequente necrose dele. Já os pacientes do GL apresentaram melhor aspecto do enxerto no último dia de avaliação. Na análise microscópica, observou-se intensa integração do enxerto à derme, reepitelização acentuada e escassas células inflamatórias no local do enxerto no GL. O contrário foi observado nos pacientes do GM e GML, nos quais aparentemente houve rejeição da membrana. A formação de colágeno não se correlacionou com outros fatores, como inflamação e necrose, em nenhum dos grupos de tratamento. Dessa forma, é possível afirmar que a laserterapia mostrou ser efetiva, contribuindo para o processo cicatricial e a integração do enxerto. Já a membrana amniótica canina não deve ser utilizada para esse fim, pois provoca intensa reação inflamatória, além de impedir a nutrição do enxerto.

Phototherapy for treating pressure ulcers

BACKGROUND

A pressure ulcer is defined as "an area of localized injury to the skin and/or underlying tissue, usually over a bony prominence, as a result of pressure, or pressure in combination with shear". The use of phototherapy - that is, light (or laser) used as an adjuvant, non-surgical intervention, with the aim of having a therapeutic effect on healing - has increased recently.

OBJECTIVES

To determine the effects of phototherapy on the healing of pressure ulcers.

SEARCH METHODS

In January 2014, we searched the Cochrane Wounds Group Specialised Register; The Cochrane Central Register of Controlled Trials (CENTRAL); Ovid MEDLINE; Ovid EMBASE; Ovid MEDLINE (In-Process & Other Non-Indexed Citations); and EBSCO CINAHL. We did not restrict the search by language or publication date.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing the effects of phototherapy (in addition to standard treatment) with sham phototherapy (in addition to standard treatment), another type of phototherapy (in addition to standard treatment) or standard or conventional treatment alone.

DATA COLLECTION AND ANALYSIS

Two review authors assessed studies for relevance and design according to the selection criteria, extracted data and evaluated study quality. The authors made attempts to obtain missing data by contacting study authors. Disagreement was resolved by consensus and discussion with a third review author.

MAIN RESULTS

We identified seven RCTs involving 403 participants. All the trials were at unclear risk of bias. Trials compared the use of phototherapy with standard care only (six trials) or sham phototherapy (one trial). Only one of the trials included a third arm in which another type of phototherapy was applied. Overall, there was insufficient evidence to determine the relative effects of phototherapy for healing pressure ulcers. Time to complete healing was reported in three studies. Two studies showed the ultraviolet (UV) treated group had a shorter mean time to complete healing than the control group (mean difference -2.13 weeks (95% CI -3.53 to -0.72, P value 0.003)). One study reported that the laser group had a longer mean time to complete healing than the control group (mean difference 5.77 weeks; 95% CI -0.25 to 11.79). However, this result should be interpreted with caution, as these were small studies and the findings may have been due to chance. Three studies reported proportions of ulcers healed with a variety of results. One study reported a different outcome measure, and the other two studies had different treatment durations. These variations did not allow us to pool the studies and draw any conclusions as to whether phototherapy is effective or not. Adverse effects were reported in only two studies that compared phototherapy with control; the risk ratio for adverse events was imprecise. One study reported risk ratio (RR) 0.72 (95%CI 0.18 to 2.80). However, another study reported RR 0.89 (95% CI: 0.71 to 1.12) based on the number of events in each group, rather than the number of people with events. Among five studies reporting the rate of change in ulcer area, three studies found no statistically significant difference between the two groups. Pooling was not undertaken because of differences in outcome measures reported. The results were based on data from trials with unclear risk of bias for which generation of the randomisation sequence, concealment allocation and blinding of outcome assessors were unclear. No studies reported on quality of life, length of hospital stay, pain or cost.

AUTHORS' CONCLUSIONS

We are very uncertain as to the effects of phototherapy in treating pressure ulcers. The quality of evidence is very low due to the unclear risk of bias and small number of trials available for analysis. The possibility of benefit or harm of this treatment cannot be ruled out. Further research is recommended.

Macroscopic effect of blue light cure on wound healing in NMRI mice NMRI

Background:

Wound healing is a complex process and has been an ongoing challenge all over the world. Some studies have suggested light cure as a modality to accelerate wound repair. It can induce fibroblast proliferation, increase collagen synthesis and activate cellular processes involved in expression of procollagen type I and III mRNA. This study was designed to assess the macroscopic effect of halogen dental curing blue light on full-thickness open wound healing in NMRI mice.

Materials and Methods:

Forty male NMRI mice were divided into control and treatment groups. A full-thickness wound of 6 mm in diameter was induced on the lower back of all mice under general anesthesia and sterile conditions. The mice of the treatment group received a 5-min exposure of halogen light Coltolux II (QHL), 420-500 nm, daily for 7 days. The diameter of the wound was measured in both the treatment and the control groups every second day up to Day 14. Data were analyzed by SPSS version 12 software using Student's t-test. A significance level of P ≤ 0.05 was considered for each comparison.

Results:

There was a significant difference in wound diameter between the control and the treatment groups at all measurements after Day 3 (P ≤ 0/05).

Conclusion:

The results of this study suggest improvement of full-thickness wound healing by daily irradiation of halogen dental curing blue light of 420-500 nm for 7 days.

Low level laser therapy for the treatment of diabetic foot ulcers: a critical survey

Diabetic foot ulcers as one of the most common complications of diabetes mellitus are defined as nonhealing or long-lasting chronic skin ulcers in diabetic patients. Multidisciplinary care for the diabetic foot is common, but treatment results are often unsatisfactory. Low level laser therapy (LLLT) on wound areas as well as on acupuncture points, as a noninvasive, pain-free method with minor side effects, has been considered as a possible treatment option for the diabetic foot syndrome. A systematic literature review identified 1764 articles on this topic. Finally, we adopted 22 eligible references; 8 of them were cell studies, 6 were animal studies, and 8 were clinical trials. Cell studies and animal studies gave evidence of cellular migration, viability, and proliferation of fibroblast cells, quicker reepithelization and reformed connective tissue, enhancement of microcirculation, and anti-inflammatory effects by inhibition of prostaglandine, interleukin, and cytokine as well as direct antibacterial effects by induction of reactive oxygen species (ROS). The transferral of these data into clinical medicine is under debate. The majority of clinical studies show a potential benefit of LLLT in wound healing of diabetic ulcers. But there are a lot of aspects in these studies limiting final evidence about the actual output of this kind of treatment method. In summary, all studies give enough evidence to continue research on laser therapy for diabetic ulcers, but clinical trials using human models do not provide sufficient evidence to establish the usefulness of LLLT as an effective tool in wound care regimes at present. Further well designed research trials are required to determine the true value of LLLT in routine wound care.