Godine describes the rapid growth of photobiomodulation (PBM)—including low-level lasers and therapeutic LEDs—as one of the fastest expanding treatment modalities in veterinary medicine. While equine practitioners have long used PBM for wound and musculoskeletal injuries, the recent surge is largely driven by companion animal veterinarians, supported by strong anecdotal reports and aggressive commercial marketing.
Abstract:
Background: For spinal-cord-injured (SCI) patients, integrative medicine approaches such as photomedicine and acupuncture can renew hope and offer previously unrecognized ways to help regain function and improve quality of life.
Objective: By understanding the mechanisms of action that these two modalities share, practitioners can better target specific attributes of spinal cord pathophysiology that are limiting recovery. Naturally occurring intervertebral disk disease (IVDD) in dogs affords unparalleled translational opportunities to develop treatment strategies involving photobiomodulation and acupuncture.
Conclusions: Insights derived through clinical trials of dogs with IVDD have the potential to raise the standard of care for both human and canine SCI patients.
Keywords: acupuncture; cellular processes; neuromodulation; outcomes research; photobiomodulation; spinal cord injury.
Absract:
The aim of this study was to evaluate the effects of high intensity laser therapy (HILT) on tendon and ligament injury treatment in horses. Twenty six horses with tendinopathies were randomly assigned to a HILT treated or to a non-treated group. Each horse was subjected to the same rehabilitation programme. Horses from the treatment group underwent a series of fifteen HILT treatments with the same parameters. Clinical and ultrasound assessments were performed by the same veterinarian and were carried out before (day 0), during (day 13-15) and after treatment (day 38-40). Clinical evaluation included: pain, swelling and lameness of the affected limb. The ultrasound examination evaluated lesion echogenicity and lesion percentage. After the treatment, pain, swelling and lameness were significantly improved by HILT compared with the control group (p = 0.023, 0.008 and 0.044, respectively). No significant changes were found in lesion echogenicity degree between both groups in measurements taken during treatment (p = 0.188) and after treatment (p = 0.070). For lesion percentage reduction, the statistical modelling showed a significant improvement in the HILT group compared with the control group during (p = 0.038) and after treatment (p = 0.019). In conclusion, HILT promoted analgesic and anti-oedema effects, with visual lameness reduction in horses with tendon and ligament injuries, and reduced lesion percentage but did not influence change in lesion echogenicity.
Keywords: high intensity laser therapy; horse; physiotherapy; ultrasound.
Abstract:
Objective: To evaluate photobiomodulation therapy in dogs with bilateral hip osteoarthritis.
Animals: 20 dogs.
Procedures: Forty joints were assigned to a control group (CG; n = 20) or treatment group (photobiomodulation therapy [PBMT]; 20). CG received a 21-day course of meloxicam, and PBMT received treatment with a Class IV therapeutic laser over 3 weeks. Joint range of motion, thigh girth, the Canine Brief Pain Inventory (divided into pain interference score [PIS] and pain severity score [PSS]), Hudson Visual Analogue Scale, Liverpool Osteoarthritis in Dogs, and Canine Orthopedic Index (COI; divided into function, gait, stiffness, and quality of life) were evaluated before treatment, +8, +15, +30, +60, and +90 days after initial treatment. Results were analyzed with repeated measures ANOVA or Wilcoxon signed ranks test, P < 0.05. Kaplan-Meier estimators were compared with the Breslow test.
Results: Patients had a mean age of 8.3 ± 1.9 years and body weight of 65.7 ± 12.1lb. Osteoarthritis was classified as moderate (n = 26) and severe (14). No differences were found at time 0. Better results were observed in PBMT at +8 days (P = 0.01 for PSS, P = 0.04 for function and COI), +15 days (P = 0.01 for PSS and function, P = 0.02 for PIS and function, P = 0.03 for COI and P = 0.04 for Liverpool Osteoarthritis in Dogs [LOAD]) and +30 days (P = 0.01 for function and gait, P = 0.02 for COI, and P = 0.04 for PIS, PSS, and LOAD). Joint range of motion improved in PBMT from +15 to 90 days. Kaplan-Meier estimators showed that PBMT produced longer periods with better results.
Clinical relevance: PBMT reduced pain levels and improved clinical findings in dogs with hip osteoarthritis.
Abstract:
The pathogenesis of myonecrosis caused by myotoxins from bothropic venom is associated with local extracellular matrix (ECM) disintegration, hemorrhage, and inflammation. Search for alternative methods associated with serum therapy is mandatory to neutralize the fast development of local damage following snakebites. The experimental use of photobiomodulation therapy (PBMT) in murine models has shown promising results relative to structural and functional recovery from bothropic snakebite-induced myonecrosis. This study pioneered in using Raman and Fourier transform infrared (FTIR) spectroscopies to characterize biochemical alterations in the gastrocnemius that had been injected with Bothrops jararacussu venom and exposed to local PBMT. Results show that vibrational spectra from lyophilized and diluted venom (1307 cm -1) was also found in the envenomed gastrocnemius indicating venom presence in the unirradiated muscle 48 h post-injection; but any longer visible after PBMT at this time exposure or 72 h post-injection regardless irradiated or not. Raman and FTIR analyses indicated that the bands with higher area and intensity were 1657 and 1547 cm-1 and 1667 and 1452 cm-1, respectively; all are assignments for proteins, especially collagen, and are higher in the PBMT-exposed gastrocnemius. The infrared spectra suggest that laser treatment was able to change protein in tissue and that such change indicates collagen as the main target. We hypothesize that the findings reflect remodeling of ECM with key participation of collagen and faster tissue recovery for an anabolic condition.
Keywords: Bothrops jararacussu; FTIR; Myonecrosis; PBMT; Raman spectroscopy; Snake venom.
Abstract:
Background and aim: Low-level laser therapy (LLLT) has shown benefits as an alternative treatment of feline chronic gingivostomatitis by reducing pain and inflammation within the oral cavity. Extraoral application technique in cats provides more comfort compared to intraoral application. However, the efficacy of LLLT through buccal tissue is still controversial. This study aimed to investigate the penetration efficacy of LLLT using 830 nm continuous waves with various settings and different application techniques.
Materials and methods: Twenty-four healthy cats were included in this study. The wavelength of LLLT was 830 nm with an output power of 200 mW through extraoral application, using fluences of 2 and 6 J/cm2 in continuous-wave mode. This study compared different distances (contact and non-contact) and three different transmission media (absent media, alcohol, and normal saline solution). Measurement of the laser power within the oral cavity is represented as the mean output power (MOP).
Results: Penetration efficacy was detectable for all fluences, distances, and transmission media, with an average buccal thickness of 2.68 mm. MOP did not differ between fluences of 2 and 6 J/cm2 (p = 0.19). In the absence of media, MOP was significantly higher compared with alcohol (p < 0.05) but was not significantly different from normal saline solution (p = 0.26).
Conclusion: Extraoral application of LLLT demonstrated penetration efficacy through the buccal tissue with both contact and non-contact skin (<10 mm). This is a potential alternative treatment for oral diseases in clinical practice. However, there is a need for further study on the efficacy of treatment in clinical practice.
Keywords: chronic gingivitis; near-infrared light; penetration; photobiomodulation; transmission.
Abstract:
Objective: The aim of this study was to determine if a single photobiomodulation treatment can reduce oral erythema and edema following routine dental prophylaxis in canines. Background: Photobiomodulation therapy has been documented to accelerate healing time through mitigation of erythema and edema in human and veterinary patients. Methods: Canine patients were randomly assigned into three groups: CG (Control, n = 9, mock gingiva treatment without irradiation), LTG (left side treated, n = 8, irradiation of left upper and lower dental arcade), and RTG (right side treated, n = 7, irradiation of right upper and lower dental arcade). Immediately following anesthetized dental prophylaxis, the canines in the RTG and LTG received four points of irradiation (GaAlInP-650 nm, continuous wave, 0.1 W, 0.2 W/cm2, 100 sec, 10 J, 20 J/cm2). Erythema and edema along the gingival surface of each dental arcade were scored 24 h after treatment by a blinded veterinary evaluator. Analysis of variance and Bonferroni correction were used for data analysis. Results: Using a composite evaluation, there was significantly lower inflammation scores for the RTG (p = 0.017) and LTG (p = 0.025) relative to the CG at the location of the lower right dental arcade. Evaluating erythema individually, a significant reduction was found in the LTG (p = 0.049) when compared with the CG for the lower left dental arcade. Conclusions: Despite the limitations in this study, the canines who received a single photobiomodulation treatment demonstrated some degree of reduction in oral inflammation and erythema following dental prophylaxis.
Keywords: canines; dental prophylaxis; inflammation; photobiomodulation.
Abstract:
Background: Staphylococcus pseudintermedius is the most common cause of bacterial skin infections in dogs. Meticillin-resistant infections have become more common and are challenging to treat. Blue light phototherapy may be an option for treating these infections.
Hypothesis/objectives: The objective of this study was to measure the in vitro bactericidal activity of 465 nm blue light on meticillin-susceptible Staphylococcus pseudintermedius (MSSP) and meticillin-resistant Staphylococcus pseudintermedius (MRSP). We hypothesized that irradiation with blue light would kill MSSP and MRSP in a dose-dependent fashion in vitro as previously reported for meticillin-resistant Staphylococcus aureus (MRSA).
Methods: In six replicate experiments, each strain [MSSP, n = 1; MRSP ST-71 (KM1381) n = 1; and MRSA (BAA-1680) n = 1] were cultivated on semisolid media, irradiated using a 465 nm blue light phototherapeutic device at the cumulative doses of 56.25, 112.5 and 225 J/cm2 and incubated overnight at 35°C. Controls were not irradiated. Colony counts (CC) were performed manually. Descriptive statistics were performed and treatment effects assessed using the Wilcoxon-Mann-Whitney rank-sum test. Bonferroni-corrected rank-sum tests were performed for post hoc analysis when significant differences were identified.
Results: There was a significant decrease in CC with blue light irradiation at all doses for MRSA (P = 0.0006) but not for MSSP (P = 0.131) or MRSP (P = 0.589).
Conclusions: Blue light phototherapy significantly reduced CC of MRSA, but not of MSSP or MRSP. The mechanism for the relative photosensitivity of the MRSA isolate is unknown, but is hypothesized to be due to an increased concentration of porphyrin in S. aureus relative to S. pseudintermedius, which would modulate blue light absorption.
Woundtreatment in animals
Abstract:
Laser therapy is becoming common place in veterinary medicine with little evidence proving efficacy or dosages. This study evaluated surgical wound healing in canines. Twelve Dachshunds underwent thoraco-lumbar hemilaminectomies for intervertebral disc disease (IVDD). Digital photographs were taken of their incisions within 24 h of surgery and 1, 3, 5, 7, and 21 days postoperatively. The first three dogs were used to create a standardized scar scale to score the other dogs’ incision healing. The remaining 9 dogs were randomly assigned to either receive 8 J/cm2 laser therapy once a day for 7 days or the non-laser treated control group. Incision healing was scored based on the scar scale from 0 to 5, with zero being a fresh incision and five being completely healed with scar contraction and hair growth. All scar scores significantly improved with increasing time from surgery (<0.001). Good agreement was achieved for inter-rater reliability (p = 0.9). Laser therapy increased the scar scale score, showed improved cosmetic healing, by day seven and continued to be significantly increased on day 21 compared to control dogs (p < 0.001). Daily application of laser therapy at 8J/cm2 hastened wound healing in Dachshunds that received thoracolumbar hemilaminectomies for IVDD. It also improved the cosmetic appearance.
Keywords: IVDD; canine; incision; laser; photobiomodulation; scar scale; wound healing.
Abstract:
The possibilities that photobiomodulation has brought on to the medical field are ever expanding and the scope it has reached is infinite. Determining how this relatively new treatment technique can be incorporated into the veterinary medical field is of interest to many medical professionals. In this review, we examine the treatment outcomes of low-level-laser therapy (LLLT) in different animal models to pinpoint any similarities between the studies. A search was conducted to identify LLLT studies using different animal models with an open or closed wound. The studies were compared to identify the laser parameters that resulted in positive treatment outcomes. The overall result of the studies examined indicated that daily laser exposure at a wavelength of a 600 or 800 nm range was the most beneficial across the rodent studies regardless of health status or wound type. More studies on rabbit, canine, and equine models are needed to explain the inconsistent results reviewed and find the correct treatment parameters for these species. Further research involving LLLT studies that focus on different factors including health status, treatment interval, wavelength, and energy density is needed to help validate our knowledge about the efficacy of using photobiomodulation in the veterinary medical field.
Abstract:
Background and aim: Chronic wounds are a clinical problem and require intensive standard wound care. However, this is sometimes insufficient to promote healing. Photobiomodulation therapy (PBMT) can be used as an adjunctive therapy to improve wound healing. Various PBMT devices with different properties and parameter settings as well as different animal species can influence a variety of clinical outcomes. This study aims to assess the use of 830 nm PBMT or simultaneous superpulsed and multiple wavelengths (SPMW; 660, 875, and 905 nm) PBMT on chronic wounds in client-owned dogs.
Materials and methods: This study included 21 client-owned dogs with chronic wounds allocated into three groups: (1) Control group (C) treated with irrigated saline and without PBMT (n=7); (2) L1 group treated with irrigated saline together with the radiation of 830 nm PBMT (n=7); and (3) L2 group treated with irrigated saline together with the radiation of simultaneous SPMW-PBMT (n=7). Wound healing was assessed on the basis of wound size reduction as a percentage of wound area every 2nd day for 15 days using image analysis software (ImageJ software®, National Institutes of Health, Rockville, Maryland, USA).
Results: A significant difference in the percentage of wound area reduction was noted between the C and PBMT groups (L1 and L2; p<0.05). The average percentages of wound area reduction at the end of the study (15 days) were 42.39±20.58, 56.98±24.82, and 61.81±27.18 in the C, L1, and L2 groups, respectively. A steady decrease in wound size was noted in both PBMT and non-PBMT groups, and coefficients were 7.77, 8.95, and 10.01 in the C, L1, and L2 groups, respectively. The percentage of wound area reduction was found to be significantly different between the PBMT and non-BPMT groups on day 7 (p<0.05).
Conclusion: Based on the results of the current study, using either 830 nm PBMT or simultaneous SPMW-PBMT can accelerate the chronic wound healing process in dogs with a significant reduction in wound area. Therefore, it can be used as an adjunctive therapy to improve wound healing in dogs with reduced treatment duration.
Keywords: canine; chronic wound; combined wavelength photobiomodulation therapy; low-intensity laser therapy; photobiomodulation therapy.
Abstract:
Background: Recent studies have reported contrasting results of the effects of laser therapy on post-operative intervertebral disk herniation, with a lack of evidence-based advantages of this modality within a rehabilitation protocol. The aim of this study was to report the clinical effects of photobiomodulation therapy within a post-operative rehabilitation protocol in dogs submitted to surgery for thoracolumbar disk extrusion. Twenty-four dogs were included in the study (12 dogs treated with laser therapy and rehabilitation protocol and 12 dogs treated with same rehabilitation protocol but without laser therapy).
Results: All dogs treated with laser therapy showed improved neurological status (Modified Frankel Score more than 3 within 30 days of physiotherapy starting) if deep nociception on admission was maintained (P = 0.04). However, Kaplan-Meier analysis did not show any statistical difference in time to regain ambulatory ability, although there was a tendency for a shorter mean time of 14.2 ± 8.55 days in the laser group versus 24 ± 18.49 days in the no laser group.
Conclusions: The use of laser therapy in the post-operative rehabilitation of dogs affected by intervertebral disc extrusion and submitted to surgery for spinal decompression could help improve their neurological status.
Keywords: Dog; Intervertebral disk extrusion; Photobiomodulation; Rehabilitation therapy; Thoracolumbar spine.
Abstract:
Class IV laser therapy has emerged as a promising non-invasive tool to promote tissue repair, but its effects on post-surgical wound healing in small animals remain underexplored. This preliminary study investigated the impact of class IV laser therapy on surgical wound healing in 49 dogs and cats. Each surgical incision was divided into a Laser Zone (LZ) and a Control Zone (CZ). Wound healing was assessed at three timepoints (T0, T1, T2) using standardized clinical parameters: skin thickness, skin color, presence of hematoma, regional temperature, skin elasticity, and presence of fluids. The LZ consistently showed reduced skin thickness, more vivid pinkish skin color, faster hematoma resolution, increased regional temperature, improved skin elasticity, and decreased fluid accumulation compared to the CZ. These effects were observed across different species, ages, sexes, and body condition scores, indicating robust biological consistency. The results suggest that class IV laser therapy accelerates post-surgical wound healing by modulating inflammation, enhancing vascularization, and supporting extracellular matrix remodeling. This technique may serve as a valuable adjunct to conventional wound management in veterinary practice. Further studies are needed to confirm these findings and explore long-term outcomes.
Keywords: cat; class IV therapeutic laser; dog; surgical wound; wound healing.