Why Wavelength Is Critical in Veterinary Laser Therapy

In veterinary laser therapy, output power determines energy intensity. However, wavelength determines tissue penetration depth and therapeutic target.    Different wavelengths behave differently in biological tissues. Their absorption and scattering characteristics are primarily influenced by chromophores such as hemoglobin, water, and melanin.    Therefore, selecting the appropriate wavelength is essential for achieving precise, efficient, and clinically effective treatment outcomes.

How Different Wavelengths Affect Tissue Penetration

Laser wavelength not only influences how deeply energy penetrates tissue, but also determines which cellular structures absorb the light and what biological effects are ultimately produced.    Based on penetration depth and tissue interaction, therapeutic laser wavelengths can generally be divided into the following ranges:

Visible Red Light (Approximately 635–650 nm)

Penetration Depth: Superficial tissues

Clinical Target: Skin and surface soft tissues

Red light is strongly absorbed by cytochrome c oxidase in mitochondria. This stimulates ATP production and reduces oxidative stress, thereby accelerating superficial tissue repair and decreasing inflammation.

Common clinical applications include:

• Superficial wound healing

• Skin inflammation

• Post-surgical incision recovery

• Small localized lesions

This wavelength is ideal when precise photobiomodulation is needed without significant deep thermal effects.

Near-Infrared (810–980 nm)

Penetration Depth: Moderate to deep soft tissue

Clinical Target: Muscles, tendons, ligaments

Near-infrared wavelengths also target mitochondria and promote photobiomodulation. They enhance deep tissue repair, reduce inflammation and edema, and relieve pain.

Because absorption at the surface level is relatively lower, near-infrared light can penetrate deeper into soft tissues. It is widely used for:

• Muscle injuries

• Tendonitis and ligament damage

• Joint inflammation

• Post-operative rehabilitation

In small animal practice, this is one of the most commonly used therapeutic ranges, offering an optimal balance between tissue penetration and photobiomodulation efficiency. It is suitable for most routine musculoskeletal conditions.

1064 nm Wavelength

Penetration Depth: Deep tissue structures

Clinical Target: Deep muscles, joints, and large treatment areas

The 1064 nm wavelength has lower scattering in tissue and higher transmission capability, allowing deeper penetration into musculoskeletal structures.

It is particularly beneficial for:

• Chronic osteoarthritis

• Deep soft tissue injuries

• Large-breed dogs and equine therapy

• Deep neuropathic modulation

For equine and large animal applications, where muscle mass and tissue thickness are substantial, deep-penetrating wavelengths are essential for delivering sufficient energy to target structures.    The 1064 nm wavelength enables more efficient therapeutic impact on deep musculoskeletal tissues.

The Mechanism of Photobiomodulation (PBM)

Regardless of wavelength, the core mechanism of therapeutic laser treatment is Photobiomodulation (PBM).    When specific wavelengths are absorbed by mitochondria, they activate cytochrome c oxidase, leading to:

• Increased ATP production

• Enhanced cellular metabolism

• Reduced inflammatory mediators

• Improved microcirculation

• Accelerated tissue repair

High-power Class IV laser therapy systems may also generate controlled photothermal effects, further improving blood flow and tissue extensibility when applied properly.

Clinical Advantages of Multi-Wavelength Laser Systems

In real clinical scenarios, injuries often involve multiple tissue layers. For example:

• A surgical incision affects both skin and muscle

• Osteoarthritis impacts cartilage, synovium, and surrounding muscles

• Equine tendon injuries involve complex multi-depth structures

A single-wavelength system may not effectively address all layers.    Multi-wavelength laser systems integrate red and near-infrared wavelengths — often including 1064 nm — to provide broader therapeutic coverage. This allows veterinarians to:

• Target both superficial and deep tissues

• Adjust parameters according to species and body size

• Improve treatment efficiency and workflow

For example, the LYRA multi-wavelength Class IV laser system combines several therapeutic wavelengths in one platform. It is suitable for both small animal and equine clinical applications, offering enhanced flexibility and expanded treatment coverage.

Key Considerations When Choosing a Veterinary Laser Therapy Device

When selecting a veterinary laser therapy system, clinicians should evaluate:

1. Whether the device offers multiple preset treatment protocols, and whether they can be adjusted

2. Whether it includes multiple wavelength configurations — and if wavelengths can be combined

3. Availability of interchangeable treatment handpieces

4. Ease of operation to improve clinical workflow efficiency

Conclusion

In veterinary laser therapy, wavelength selection directly influences treatment outcomes.    Rather than focusing solely on output power, veterinary professionals should prioritize wavelength combinations, tissue penetration capability, and clinical adaptability.    As laser technology continues to evolve, multi-wavelength Class IV laser systems provide veterinary clinics with more comprehensive and efficient treatment solutions.

If you are looking for a system capable of covering both superficial and deep therapeutic needs, explore the LYRA multi-wavelength laser therapy solution to expand your clinical possibilities.