Theralase designs and manufactures high quality therapeutic medical laser systems for the international medical rehabilitation community. Theralase manufactures the TLC-1000 portable model therapeutic medical laser systems with a variety of probe configurations designed for specific healthcare practitioner applications
Technology
Laser Design Parameters and Tissue Interaction
Wavelength
There are 3 main components of tissue that affect the absorption of light, specifically:
water, haemoglobin (pigment that renders blood red) and melanin (pigment that
gives skin its natural colour). The absorption curves for these three substances
versus the laser wavelength will determine the precise impact that a particular
laser will have on tissue.
This laser light has the unique properties of monochromaticity, (a single wavelength), coherence (travels in a straight line) and defined location (concentrated beam). These properties are what allow lasers to penetrate the skin surface, non-invasively, delivering energy directly to the cells which the cells then convert into chemical energy.
T. Oshiro, a leading expert on therapeutic medical lasers, testifies to the effectiveness of the 905nm laser in his book Low Level Laser Therapy: A Practical Introduction:
"The peak of tissue penetration is around 900 nm. This would appear to make the GaAlAs diode system the most effective LLLT (Low-Level Laser Therapy) system for penetrating to the desired depth. In addition the comparative cost of a GaAlAs makes it both financially and biomedically competitive. The near infrared GaAlAs diode laser systems are even more inexpensive than the HeNe systems, and are also proving more effective in therapy."
Power
The power of a laser determines how much energy is initially delivered to the
tissue surface and along with the wavelength, the power at any given depth of
penetration. Energy density (Joules / centimeter2) is equal to the power of
the laser in watts multiplied by the treatment time in seconds, divided by the
surface area irradiated in square centimetres.
Energy Density = (Power x Time) / Surface Area
Continuous versus Pulsed Wave Technology
A super pulsed laser such as the Theralase therapeutic medical laser uses a
peak power up to 50 Watts (50,000 mW) delivering this energy in a fraction of
a second (200 billionths of a second) for an average power output of 100 mW.
A super pulsed laser system has a peak power which is 500 times greater than the peak power of a continuous wave system of the exact same average power rating.
The Theralase laser system achieves tissue penetration by delivering powerful bursts of energy versus a continuous output, which has difficulty penetrating different densities of tissue.
Delivery System of Laser Probes
In order for your laser system to provide optimal penetration through the skin
it must be in direct contact with the skin and be at an incident angle of 90
degrees (perpendicular to the skin). This will minimise any reflection from
the skin's surface and allow the best penetration into the tissue. The Theralase
therapeutic laser system's unique design ensures each and every probe is always
in direct contact with the skin surface, thus minimising surface reflection.
True Lasers versus Super-luminous Diodes
True lasers such as the Theralase system focus all of their energy in one direction
in a very concentrated line. A super-luminous diode, on the other hand, diffuses
its energy in all directions with only a small percentage of the energy travelling
in the direction of the treatment. A true laser system will deliver over 90%
more power to the treatment area than a super-luminous diode system of exactly
the same average power rating.
Summary
In order for a therapeutic laser system to be efficacious and time efficent for your treatment applications, remember that the deeper in tissue that you wish to penetrate the more optimal the following laser characteristics must be chosen:
Wavelength affects the depth of tissue penetration and ability of the photons
to perform photo chemistry.
Peak Power affects the depth of tissue penetration and the quantity of photons
per unit time at depth sufficient to create biostimulation.
Average Power affects the total quantity of photons available at the tissue
surface.
Delivery systems affect the ability of the photons to penetrate the tissue surface.
Laser versus LED's affect the quantity of photons moving in a forward vector
to penetrate the tissue surface.
Vendor Comparison
Laser System: Theralase TLC-1000 Mfg. A Mfg. B Mfg. C
Wavelength: 905 nm/ 660 nm 830 nm 635 nm 635 nm
Average Power: 100 mW/ 20 mW 30 mW 5 mW 5 mW
Peak Power: 50,000 mW 30 mW 10 mW 5 mW
# of Diodes: 9 3 2 4
Total Power: 5 x 100 mW + 4 x 25 mW = 600 mW 3 x 30 mW = 90 mW 2 x 5 mW = 10
mW 4 x 5 mW = 20 mW