Class 4 Laser Therapy: Debunking Myths With Clinical Evidence

In the evolving landscape of laser therapy, the allure of cutting-edge technology can sometimes overshadow the foundational principles guiding therapeutic efficacy and safety. Class 4 lasers, with their high-power credentials, have been gaining popularity in the market, promising deeper penetration, superior biostimulation effects, and uncompromising safety. But how much of this is marketing buzz, and how much is substantiated by scientific research? In this article, we’ll delve deep into the claims surrounding Class 4 lasers, comparing them against their Class 2/3 counterparts, and decipher the myths from the realities. Our objective is to arm practitioners and patients with evidence-based knowledge, ensuring informed decisions in the realm of laser therapy.

A woman being treated with an LLLT device for pain relief — Erchonia’s **EVRL® Laser**: The only **low-level laser** to be FDA Market Cleared for treating chronic / acute back, neck, and shoulder pain, and pain associated with surgery.

Laser Classifications and FDA Approvals

Before diving into the intricacies, it is important to distinguish between High-Powered Laser Therapy (also referred to as High-Intensity Laser Therapy or High-Level Laser Therapy) and Low-Level Laser Therapy (LLLT). To help with the distinction, we can use the following classification criteria of the FDA:

High-Powered Laser Therapy devices are classified as ‘Class IV Lasers’ in virtue of having a power output that’s greater than 500mW (i.e. high risk of hazard). The vast majority of such devices have longer near-infrared wavelengths.
LLLT devices are classified as either ‘Class IIIB Lasers’, ‘Class IIIR Lasers’, or ‘Class II Lasers’ in virtue of having a power output of 5-500mW, 1-5mW, or <1mW respectively (i.e. lower risk of hazard). The vast majority of LLLT devices have shorter wavelengths.

The first FDA market clearance for laser therapy, gained by an Erchonia® low-level laser, catered to chronic neck and shoulder pain. The laser employed was a 5mW 635nm line-generated beam, with a singular treatment duration of 4 minutes. Astoundingly, the results indicated a 64% pain reduction in all treated patients compared to the placebo group, coupled with enhanced muscle strength and improved range of motion.

With this approval, a new category called NHN was introduced for ‘Powered Light Based Laser Non-Thermal Instrument With Non-Heating Effect For Adjunctive Use In Pain Therapy’.

Interestingly, the FDA only cleared the first high-power therapeutic laser for the market in 2004, two years after the approval of the inaugural low-level laser. This device, produced by a company that drew parallels between it and a standard heat lamp, received clearance for topical heating and muscle relaxation. Notably, no other high-powered laser has earned a 510(k) market clearance based on individual clinical trials to date. In contrast, low-level lasers have been the focus of extensive clinical, cellular, and molecular studies.

Biostimulation and High-Power Lasers: Dissecting the Truth

Diving deeper into the subject, Jan Tunér and Lars Hode’s publication on laser therapy concludes that the range for therapeutic biostimulation is between 0.5 to 1 J/cm² on open wounds and 2-4 J/cm² on skin. To provide some perspective, for a patient to achieve the upper limit of 4 joules essential for biostimulation, merely a one-second treatment with a 4-watt laser or a 0.5-second treatment with a 10-watt laser would suffice.

In line with this, a quintessential study showcased in Photomedicine and Laser Surgery employed 685nm and 830nm lasers to study tissue repair in tendons of mice. The authors divided their subjects into six distinct categories: two as placebo, two under the 685nm (red) laser at 3 joules and 10 joules, and two subjected to the 830nm (infrared) laser at similar energy levels. A comparative analysis of the results revealed superior outcomes with the 685nm laser at 3 J/cm², while the 830nm laser at 10 J/cm² yielded the least favorable results for healing. Similar findings have been published since at least 1989, when Shiroto stated that “an increase in irradiation dose may decrease biostimulatory effects.”

Such findings resonate with the Arndt-Schulz Law which proclaims that while weak stimuli can invigorate biological activity, stronger stimuli might dampen it. More generally, laser therapy devices can reach a limit, termed bio-inhibition, beyond which they no longer effectively influence the intended physiological structures. This threshold, as detailed by Farouk Al-Watban in several studies, is well-established in literature. High-powered lasers, with their substantial power outputs, risk surpassing this limit.

Furthermore, there is evidence to suggest that wavelengths exceeding 730nm are unable to provide the minimum 1.7eV energy per photon required for therapeutic biostimulation via photochemical means.

To give an example, a study by Moriyama et. al investigated the efficacy of LLLT in modulating inducible nitric oxide synthase (iNOS) expression as a molecular marker of the inflammation signaling pathway. The authors concluded that the time integrated iNOS signal during the acute inflammation phase was not affected by LLLT using near infrared wavelength at 785, 808, and 905nm, whereas LLLT mediated by 635nm showed a significant upregulation of iNOS. Considering the low quantum energy per photon for the 785 to 905nm range, equal to 1.52 to 1.37eV, they can apparently not induce direct photochemistry as the minimum quantum energy for cis-trans isometration is on the order of 1.7eV.

Similarly, Tiina Karu’s seminal work Ten Lectures on Basic Science of Laser Phototherapy draws attention to a pivotal study by Rochkind et. al. This study discovered that wavelengths 540nm and 632nm significantly influenced the action potential of nerves. Conversely, wavelengths 904nm, along with CW radiation at 830, 880, and 950nm, displayed no such impact.

These studies suggest that high-powered lasers, which often operate within these longer wavelengths, may not primarily function through inducing photochemical reactions. Instead, they might rely on alternative mechanisms, such as the therapeutic influence of localised heat generation. However, this approach may be less efficacious compared to biostimulation by photochemistry.

The Lack of Evidence Behind High-Power Laser Penetration Claims

Proponents of high-powered laser devices often assert that their equipment offers superior power and depth of penetration than LLLT devices. Yet, there is a glaring absence of evidence to suggest that these high-priced devices, which can fetch up to $50,000, outperform LLLT.

Manufacturers of potent lasers often remove the collecting lens, a strategic move to prevent potential skin burns. Furthermore, users must employ a manual scanning technique, moving the device continuously over the skin to avoid injuring the tissue. This methodology indicates that high-powered lasers aren’t penetrating as deeply as one might assume. This perspective is supported by Tunér and Hode in their piece Confounders and Magicians where they remark upon the 980nm wavelength’s reduced penetration capability due to the high absorption by water in the skin’s upper layers, thereby increasing the risk of overheating. Orazio Svelto, in his book Principles of Lasers, also highlights the significant absorption properties of water in relation to near-infrared wavelengths.

Further evidence comes from a pivotal MRI study by Dr. Rodrigo Neira, published in the American Journal of Cosmetic Surgery. This research showed that an 8mW 635nm laser, placed 6 to 8 inches from the skin, could emulsify deep fat up to 6cm and reduce the appearance of scar tissue. Abdominal MRIs taken at intervals of 0, 4, and 6 minutes on both T-1 and T-2 weighted sequences corroborated these observations. Dr. Robert Jackson’s study in the AJCS provided additional validation for these findings.

Contrastingly, an article in Dynamic Chiropractic titled Basic Principles of Low-Level Laser Therapy claimed that red light at 640nm primarily affects the skin and might be suitable for addressing cuts, scars, trigger points, and acupoints, but with a typical penetration depth of less than 10mm. This article however, lacked supporting research, starkly contrasting with the evidence endorsed by the FDA and the findings of the previously mentioned studies. This raises the question of whether some individuals in the field might be drawing conclusions based more on existing literature and affiliations rather than their own original research. This sentiment is echoed by Tunér and Hode, who observed that several individuals in the laser community offer insights without extensive clinical or cellular research to support their claims.

Safety Concerns and the Power Spectrum: The Fine Line Between Therapeutic and Harmful Laser Exposure

The long-term safety of high-powered lasers remains under discussion, as existing research has not provided definitive support for their use. A significant portion of the reference materials pertaining to high-powered lasers often cites studies done on low-level, low-energy lasers, instead of their high-powered equivalents.

A study from January 2006 in Lasers in Surgery and Medicine highlights potential risks, suggesting that merely 10 joules could damage cellular DNA and compromise cell viability. Notably, the laser featured in this study was a 3mW type with a divergent beam, indicating its relative safety compared to lasers with narrow parallel beams.

Furthermore, a well-established medical consensus, bolstered by the ASLMS study from January 2006, is the understanding that skin heating leads to the generation of free radicals.

Conclusion

In the realm of laser therapy, it is crucial to differentiate between marketing hype and scientifically backed facts. Our exploration of Class 4 lasers has shed light on the many misconceptions surrounding their depth of penetration, biostimulation effects, and overall safety. As consumers and healthcare professionals, it’s essential to base decisions on rigorous clinical evidence, ensuring optimal results and patient well-being. The key takeaway? Always challenge claims, stay updated with emerging research, and prioritize safety and efficacy over brand promises.

Common FAQs About Erchonia®

What Is the Scientific Evidence Behind Erchonia® Lasers?

All studies carried out to obtain FDA-clearance are double blind, randomised, placebo-controlled, and multi-site – the most credible research of all Laser Therapy devices on the market today.

The following list shows the clinical trials and an outline of their progress. As a company, to protect our intellectual assets, not all clinical trials we are involved with are made public so as to maintain our competitive advantage. As such, not all clinical trials are listed below.

Please note: There are hundreds of clinical studies confirming the effectiveness of Low-Level Laser Therapy (LLLT), and every year there are many new publications. Below is a list of Erchonia-specific studies for FDA-clearance.

1) Chronic Neck and Shoulder Pain / Low Level Laser — 2000 — Sponsor and monitor, IRB approved, double blind, placebo controlled, multi-site, clinical study.

First study done in support of 510(k) submission, second study requested by FDA.

2) Chronic Neck and Shoulder Pain / Low Level Laser — 2001 — Sponsor and monitor, IRB approved, double blind, placebo controlled, multi-site, clinical study.

Study results used to obtain FDA clearance – K012580
To view NIH clinical trial records, click here.

3) Low Level Laser Light Therapy as an Aid to Liposuction and Reduction of Pain Associated With Surgery — 2004 — Sponsor and monitor, IRB approved, double blind, placebo controlled, multi-site, clinical study.

Study results used to obtain FDA clearance –K041139
To view NIH clinical trial records, click here.

4) Acne Vulgaris — Dermatological Conditions / Low Level Laser — 2005 — Sponsor and monitor, IRB approved, double blind, placebo controlled, multi-site, clinical study.

FDA clearance – K050672

5) Pain Associated With Breast Augmentation Surgery / Low Level Laser — 2007 — Sponsor and monitor, IRB approved, double blind, placebo controlled, multi-site, clinical study.

Results used to obtain FDA clearance – K072206
To view NIH clinical trial records, click here.

6) Non-Invasive Fat Reduction and Body Contouring – Laser Scanner Waist, Hips, and Thighs — 2009 — Sponsor and monitor, IRB approved, double blind, placebo controlled, multi-site, clinical study.

Study results used to obtain FDA clearance – K082609
To view NIH clinical trial records, click here.

7) Equine Wound Healing – 2011 — Sponsor, Case Study.

Study completed from Nov. 2010-March 2011.
Monitored by Hank Jann, DVM, MS, DACVS from Oklahoma State University.

8) Equine Wound Healing – 2011 — Sponsor, placebo controlled, clinical study.

Study completed from Feb. 2011-April 2011.
Monitored by Hank Jann, DVM, MS, DAVCS from Oklahoma State University.

9) Arm Circumference Reduction of the Upper Arms — 2011 — Sponsor and monitor, IRB approved, double blind, placebo controlled, multi-site, clinical study.

Study results used to obtain FDA clearance – K120257
Study submitted to be published 2012.
To view NIH clinical trial records, click here.

10) Appearance of Cellulite (Verju Laser System) — 2012 — Sponsor and monitor, IRB approved, double blind, placebo controlled, multi-site, clinical study.

FDA clearance – K130922
Study submitted to be published 2013.
To view NIH clinical trial records, click here.

11) Non-Invasive Body Contouring Using GLS Laser – 532 nm (Green) Trade Name Verju — 2012 — Sponsor and monitor, IRB approved, double blind, placebo controlled, multi-site, clinical study.

FDA clearance – K123237
Study submitted to be published 2013.
To view NIH clinical trial records, click here.

12) Adjunct to Chronic Heel Pain Arising from Plantar Fasciitis Using the Erchonia FX635 Laser — 2012 — Sponsor and monitor, IRB approved, double blind, placebo controlled, multi-site, clinical study.

FDA clearance – K132940
Study results published in the American Orthopaedic Foot & Ankle Society April 2014
To view NIH clinical trial records, click here.

13) Non-Invasive Dermatological Aesthetic Treatment for Reduction of Circumference of Hips, Waist and Upper Abdomen When Applied to Individuals with a Body Mass Index (BMI) Between 30 kg/m2 and 40 kg/m2 — 2013 – Sponsor and monitor, IRB approved, double blind, placebo controlled, multi-site, clinical study.

FDA clearance – K142042
To view NIH clinical trial records, click here.

14) Non-Invasive Dermatological Aesthetic Treatment for the Reduction of Circumference of Hips, Waist and Thighs (Zerona-Z6 OTC) — 2012 — Sponsor and monitor, IRB approved, double blind, placebo controlled, multi-site, clinical study.

FDA clearance – K143007
To view NIH clinical trial records, click here.

15) Non-Invasive Dermatological Aesthetic Treatment for the Reduction of Circumference of Hips, Waist, Thighs and Upper Abdomen — 6 Week Treatment Protocol (Zerona-Z6) — 2014 — Sponsor and monitor, IRB approved, double blind, placebo controlled, multi-site, clinical study.

FDA clearance – K150446
To view NIH clinical trial records, click here.

16) Erchonia EVRL (EVRL) – 2016

a. while using the red diode, for adjunctive use in providing temporary relief of minor chronic neck and shoulder pain of musculoskeletal origin.

b. and while using the violet diode, to treat dermatological conditions, and specifically indicated to treat moderate inflammatory Acne Vulgaris.

FDA clearance – K152196

17) Temporary Increase of Clear Nail in Patients With Onychomycosis (e.g., Dermatophytes Trichophyton Rubrum and T. mentagrophytes, and/or Yeasts Candida Albicans, etc.) (Lunula Laser ) — 2016 — Sponsor and monitor, IRB approved, blind, placebo controlled, clinical study.

FDA clearance – K153164
To view NIH clinical trial records, click here.

18) Non-Invasive Dermatological Aesthetic Treatment for the Reduction of Body Circumference (Zerona-Z6) — 2016.

FDA clearance – K162578

19) Market Clearance to Treat Chronic Low Back Pain (FX 635) — 2018 — Placebo-controlled, randomized, double-blind, parallel-group, multi-center clinical study.

FDA clearance – K180197
To view NIH clinical trial records, click here.

20) Market Clearance for Relief of Chronic Musculoskeletal Pain (FX 635) — 2019 — A collection of placebo-controlled, randomized, double-blind, parallel-group, multi-center clinical studies.

FDA clearance – K190572

21) Non-Invasive Dermatological Aesthetic Treatment for the Reduction of Body Circumference in Individuals With a Body Mass Index (BMI) of up to 40 kg / m² — 2019 — The data used to get this approval combined all previous data Erchonia® had on 20-40 BMI patients in the green laser studies above.

How Do Erchonia® Lasers for Pain Relief Work?

While the benefits of Low-Level Laser Therapy (LLLT) have been observed in hundreds of medical studies, the exact mechanisms that lead to these results are still being explored. Although we still have a lot to learn about the effects of light energy on different types of cells, the leading theory is that LLLT generates therapeutic effects through stimulating and enhancing specific biochemical processes within cells.

More specifically, utilising the first law in photochemistry (Grotthuss-Draper law), laser energy is transferred to cytochrome c oxidase (CcO) – a respiratory energy-transducing enzyme which is involved in the electron transport chain in mitochondria. This energy transfer causes photodissociation of inhibitory nitric oxide from CcO, leading to an enhancement of enzyme activity, electron transport, mitochondrial respiration, and adenosine triphosphate (ATP) production. Consequently, by altering the cellular redox state, LLLT induces the activation of numerous intracellular signalling pathways, and alters the affinity of transcription factors concerned with cell proliferation, survival, repair, and regeneration.

Erchonia® pain relief lasers utilise true laser technology, optimising photonic energy delivery through the use of monochromatic, collimated, and coherent beams of light. That is, the light emitted by a true laser is composed from photons that have the same wavelength (monochromatic), travel in the same direction / do not disperse (collimated), and are in phase in space and time (coherent). These three properties of true lasers make them the most effective and efficient devices within the Laser Therapy sector.

Erchonia® lasers were specifically designed to deliver the optimal amount of energy required to stimulate and enhance cell function while not damaging cells or producing painful heat sensations – all of our non-thermal LLLT devices are classified as ‘Class II Lasers’ by the FDA in virtue of their low output and very low risk of hazard.

How Do Erchonia® Lasers for Fat Removal Work?

Erchonia® fat removal lasers create a small transitory pore for the fatty liquids in fat cells to seep out. The fatty liquids are then naturally flushed out through the lymphatic system.

The result is that the fat cells shrink instead of being killed. When this happens, the shrunken fat cells begin to act and function like healthy lean cells, releasing the correct messages to the brain and creating a communication effect throughout the fat organ, causing other fat cells to release their content and return their hormone responses to the positive.

Procedures that have been popular in the past (such as fat freezing) focus on the elimination of fat cells, but recent research has shown this approach to be less effective, and in the worst-case scenario, providing counterproductive results.

Erchonia® lasers effectively train fat cells to behave and react differently, and all without excessive heat or cooling.

How Do Erchonia® Lasers for Fungal Nail Treatment Work?

Erchonia® lasers for fungal nail treatment target onychomycosis through the use of two true laser beams (red 635nm and violet 405nm – monochromatic, collimated, and coherent).

The two wavelengths trigger a photochemical reaction, producing Reactive Oxygen Species which is converted to Hydrogen Peroxide – a natural antiseptic that kills onychomycosis.

In addition, the red 635nm wavelength induces the production of Adenosine Triphosphate (ATP) which is converted to Nitric Oxide – aiding the natural immune response in fighting the infection.

What Are the Biological Effects of Low-Level Laser Therapy (LLLT)?

Clinical studies and trials of Laser Therapy technologies indicate the following beneficial effects of Low-Level Laser Therapy (LLLT).

Anti-Inflammation. LLLT creates an anti-edema effect by dilating blood vessels and activating the lymphatic drainage system (which drains swollen areas). This reduces swelling caused by trauma or inflammation.
Anti-Pain (Analgesic). LLLT exerts a very beneficial effect on pain in multiple ways: It partially blocks neural transmission of pain signals to the brain; It decreases nerve sensitivity; It lessens pain by reducing edema; It helps to increase the production of high levels of painkilling chemicals such as endorphins, enkephalins, and opioids from the brain and adrenal gland.
Accelerated Tissue Repair and Cell Growth. Photons of light from lasers penetrate deeply into tissues and accelerate cellular reproduction and growth. The laser light also increases the energy available to the cell by increasing ATP production so that the cell can take on nutrients faster and get rid of waste products. As a result of exposure to laser light, all cells, including the cells of tendons, ligaments, and muscles, are repaired faster.
Improved Vascular Activity. LLLT significantly increases the formation of new capillaries in damaged tissue, which speeds up the healing process, closes wounds more quickly, and reduces scarring. LLLT also causes vasodilation – an increase in the diameter of blood vessels – which improves the delivery of blood and healing elements to damaged tissues.
Increased Metabolic Activity. LLLT stimulates higher outputs of specific pro-healing enzymes in blood cells, along with improved oxygen and nutrient delivery.
Trigger Points and Acupuncture Points. LLLT stimulates muscle trigger points and acupuncture points on a non-invasive basis, providing musculoskeletal pain relief.
Reduced Fibrous Tissue Formation. LLLT reduces the formation of scar tissue following damage from cuts, scratches, burns, or surgery.
Improved Nerve Function. Slow recovery of nerves in damaged tissue results in impaired sensory and motor function. LLLT speeds up the process of axonal regeneration and nerve cell reconnection, and increases the amplitude of action potentials to optimize muscle action.
Immunoregulation. LLLT directly affects immunity status by stimulating the production of immunoglobulins and lymphocytes, and by improving the ease of penetration of white blood cells into damaged tissue.
Faster Wound Healing. LLLT stimulates fibroblast development in damaged tissue. Fibroblasts are the building blocks of collagen, which is the essential protein required to replace old tissue or repair tissue injuries. As a result, LLLT is effective on open wounds and burns.

What Is the Difference Between Erchonia® and Other Technologies in This Market?

The efficacy of Erchonia® lasers has been scientifically proven with double blind, randomised, placebo-controlled, and multi-site studies. Many competing companies advertise their products as ‘clinically proven’, guaranteeing ‘instant results’. However, these claims are often not backed by comprehensive clinical evidence.

Several companies have FDA-clearance within the Laser Therapy sector, however, in most cases the intended use / indications of their products are quite limiting or not relevant to the marketed applications. Furthermore, these FDA-clearances are often obtained without any scientific research.

We always recommend that you ask for details of the FDA-clearances and make an informed decision. Pay particular attention to the scope of the clearance, whether it involved clinical studies, how many patients participated, were the studies placebo controlled, double blind, and randomised, how many peer reviewed published articles they have, and what the adverse reactions / side effects were – we would be happy to provide this information for you.

What Conditions Can Erchonia® Pain Relief Lasers Help With?

Erchonia® pain relief lasers can help a wide variety of patients, including: Orthopaedic pain – sprains, whiplash, muscular pain, cervical or lumbar radiculopathy, tendinitis, and carpal tunnel syndrome. Our devices have also shown positive effects on individuals with chronic conditions like arthritis and osteoarthritis, and in treating post-surgical pain; Neuropathic pain, including various types of neuralgia and diabetic neuropathy; Pain management for athletes recovering from training or injuries.

What Areas Do Erchonia® Fat Removal Lasers Treat?

Erchonia® lasers for fat removal treat overall body circumference while also allowing your clients to target stubborn areas of fat and cellulite.

Most people who undergo the treatments focus on their midriff and thighs, but the device can also target any area of subcutaneous fat, including bra strap, upper arms, jowls, knees, and more.

Are There Any Conditions Which Would Prevent Patients From Receiving the Treatments?

There are no code regulated contraindications, however, since there are no long-term evaluations on certain conditions, we do not recommend using Erchonia® non-thermal lasers on pregnant women, clients with a pacemaker, or clients with photosensitive epilepsy. We also do not recommend using our devices over an area of known cancer.

Will Erchonia® Lasers Cause Pain or Burning?

Erchonia® are true Non-Thermal Low-Level Lasers and cause no pain or health risks.

What Do Erchonia® Lasers Treat and How Are They Used?

Erchonia® lasers are used in many areas, such as 360-degree fat loss, body sculpting, cellulite reduction, pain management, pre / postsurgical healing, pre / rehabilitation, nail and skin pathologies (e.g. nail fungus and acne), and more.

Not only do our lasers treat specifics, but they also empower the body to function efficiently due to the beneficial effects they have on our cells.

Why Choose Erchonia®?

With over 25 years of experience, 16,000+ devices in the market, and 21 FDA-clearances, Erchonia® Corporation are world leaders in medical-grade Laser Therapy technology for physicians, chiropractors, physical therapists, podiatrists, osteopaths, aesthetics clinics, veterinarians, and many other types of medical / health professionals.

Erchonia® own 21 of the 24 FDA-clearances given to Low-Level Lasers, and the efficacy of our devices has been proven by multiple (level 1) double blind, randomised, placebo-controlled, and multi-site clinical studies – the most credible research in the market today.

All Erchonia® laser systems are cut from raw materials, and all of our products go through a rigorous quality control process before delivery to our customers around the world. As a company, we are 85% self-reliant in all facets of our organisation, and all of our products are FDA, ISO, OSHA, and MDSAP compliant.

The Erchonia® mission statement is simply “Quality Not Compromise”, and this is ingrained in every aspect of our business – from an unwavering belief in the limitless potential applications of Low-Level Lasers, down to the care and quality of the smallest component of our devices. Just pick up any Erchonia® product, feel the quality of workmanship, and see the attention to detail that can only come from Erchonia’s near-complete control of the manufacturing and assembly processes that go into each product bearing the Erchonia® name. Read More