What is Class 4 Laser?
Laser therapy is the most effective modality in treating pain. It can treat acute and chronic injuries, sprains and strains, arthritis, swelling due to back disc problems, and muscular-skeletal abnormalities. It also helps to regenerate nerve tissue after surgery.
Class 4 laser used to generate heat but with new technology, it does not generate heat anymore. Hence it being considered as a cold laser. However the difference between Class 3B and Class 4 laser is the power being emitted – Class 3B has a lower power level as compared to Class 4.
Class 4 laser is the application of red and near infra-red light over injuries or lesions to improve wound and soft tissue healing, reduce inflammation and give relief for both acute and chronic pain. It is stronger as it has a higher power to drive more light energy to heal tissues effectively. First developed in 1967, it is now commonly referred to as LLLT.
LLLT is used to: increase the speed, quality and tensile strength of tissue repair; resolve inflammation and relieve pain (analgesia).The red and near infrared light (800nm) commonly used in LLLT can be produced by laser or high intensity LEDs. The intensity of LLLT lasers and LED’s is not high like a surgical laser. There is no heating effect. The effects of LLLT are photochemical (like photosynthesis in plants). When the correct intensity and treatment times are used, red and near infrared light reduces oxidative stress and increases ATP. This improves cell metabolism and reduce inflammation. These effects can be enhanced with pulses however when analgesia is required there is a second mechanism which works best when a strong continuous beam is applied. Lasers are nothing more than a beam of light that travels at a certain frequency that allows the laser to generate heat and penetrate tissue. Some Class IV or cold lasers are programmable to a range of frequencies in order to treat many different types of problems in dogs.
Pre and Post Surgery Care
Class 4 Laser has been known for almost 50 years since shortly after the discovery of lasers in 1960. For many years it was thought that there was something special about laser light, but it is now known that many wavelengths of visible light (especially in the red or near-infrared regions) produced from LEDs or other light sources are equally effective. Longer red and near-infrared wavelengths are much better at penetrating tissue than shorter blue/ green wavelengths and are therefore preferred clinically.
Although the mechanism of action of LLLT is still not fully understood, much information is now known concerning the primary photoacceptor molecules, the immediate effectors, the signaling pathways, transcription factor activation and short and long-term effects of LLLT on cells and tissues. The most important photoacceptor is accepted to be cytochrome c oxidase (unit IV in the mitochondrial respiratory chain). Increase in mitochondrial membrane potential, oxygen consumption and ATP production are rapidly observed. Nitric oxide and ROS are transiently produced. Cyclic AMP is involved in signaling pathways. Transcription factors such as NF-kB are activated. Anti-apoptotic proteins, heat shock proteins, anti-oxidant defense pathways and anti-inflammatory cytokines are increased. In the long-term parameters involved in healing such as cell migration, cell adhesion, protein synthesis, and DNA synthesis are stimulated. Many vets in US are using LLLT as a pre and post surgery therapy to aid in healing.
The Science behind Cold Laser
For tissue to absorb light and alter its physiology, a photochemical or photobiologic event must occur. Ideally, this event would take place within the target tissue(s), whether it be skin, muscle, fascia, nerves, vessels, bones, and/or joints. A “photoacceptor” molecule, also known as a “chromophore,” responds to light by initiating a series of physiologic responses that engender healing and improved tissue homeostasis. When a chromophore (such as cytochrome c oxidase in the mitochrondria respiratory chain) absorbs a photon from laser-treated tissue, an electron within the chromophore becomes excited and jumps from a low- to a higher-energy orbit. This increased electron energy provides the impetus for the system to perform cellular activities geared toward growth and repair.
Rather than categorizing Cold Laser Therapy as a quack therapy, below are proper research papers on this theraphy.
- Thor Laser
- Role of Low-Level Laser Therapy in Neurorehabilitation
- Cryolipolysis for noninvasive body contouring: clinical efficacy and patient satisfaction
- The Nuts and Bolts of Low-level Laser (Light) Therapy
- Low-level laser (light) therapy (LLLT) on muscle tissue: performance, fatigue and repair benefited by the power of light
- Photomedicine and Laser Surgery
- Low Level Laser Therapy with Trigger Points Technique: A Clinical Study on 243 Patients
- Current Rheumatology Reviews
- Effect of Low-Intensity Laser Irradiation on the Process of Bone Repair