“I use the Theralase Laser to keep my throwing arm healthy. It reduces fatigue and allows me to play at my peak game after game after game.”
Roy Halladay
#32 Toronto Blue Jays
(2003 Cy Young Award)
Frequently Asked Questions
Is laser (LLT) therapy scientifically documented?
There are thousands of published studies that describe the positive effects of laser therapy. These studies range from studies on individual cell types to in vivo double blind control studies. The areas of study range from wound healing to muscular skeletal conditions and have been conducted on different types of laser devices. Medicine is a very good medical database search engine that can provide abstracts and can sell literature. There are also many books on the subject. One very good text is “Low Level Laser Therapy-Clinical Practice and Scientific Background”, written by Jan Turner & Lars Hode.
How deep into tissue can a laser penetrate?
The depth of penetration of laser light depends on many parameters such as the laser’s wavelength, the power, the type of device driver (pulse or continuous wave mode), and lastly the technique used. The higher the wavelength typically the deeper the penetration; however, with wavelengths greater than 950nm the water in the tissue absorbs light and the depth of penetration is drastically reduced in addition to causing heat. Secondly devices of greater power can provide better penetration. Thirdly, the peak power of the unit is the most critical factor in providing depth of penetration. Thus, devices which are true pulsed have better penetration versus continuous wave devices because they have greater peak power densities for superior photon concentrations at depth.
The TLC-1000 series of Therapeutic Medical Lasers can provide a direct penetration of tissue 5 cm into tissue and an indirect penetration up to 10 cm.
What is the relationship between Peak Power and Average Power?
Average power is computed by multiplying the device’s peak power by the pulse frequency and the pulse duration. Since continuous wave units are not pulsed, the pulse duration and the pulse frequency are both equal to 1 and thus the unit’s average power. Some manufacturers of continuous wave devices have chopped the output to create a pulsing effect. It is important to note that in continuous wave units with a fixed 50/50 duty cycle that the average power of the laser system is reduced to ½. In a true pulsed laser system, increasing the frequency, increases the number of super pulses and hence, increases the average power output. The peak power of a continuous wave device is typically measured in milliwatts whereas in a true pulsed laser the peak power is measured in watts or thousands of milliwatts.
Are there harmful side effects/contraindications?
No, although one must never shine the laser directly into the eye. Otherwise, we recommend that laser devices not be used on the abdomen of a pregnant woman, in the presence of photosensitive compounds or directly on any cancerous tissue.
Does it have to be a laser?
Some manufactures produce devices with super-luminous diodes instead of true laser diodes because they are much cheaper to produce.Super-luminous diodes produce monochromatic light, but it is not coherent and hence scattered in all directions.Studies have shown that lasers are much more effective because of their superior photon density.The most common application for super-luminous diodes is for superficial wounds and surface dermatological conditions.Since these devices are very low powered, (approximately 5 to 15 mW rated and only 1 mW actual) and much of the energy they deliver is scattered, they will require much longer periods of treatment time.Most importantly, super-luminous diodes because of their low photon density will not be effective at delivering energy to tissues below the dermis.
How do I know which laser I should buy?
Here are some tips to help determine which instruments are good value for your money:
1. “Laser instruments” have been sold which do not even contain a laser, but LEDs and sometimes even ordinary light bulbs.These instruments have been sold for between US $3,000 - $10,000.Ask for proof that the instrument really does contain a laser.
2.In a number of products, laser diodes have been combined with LED’s.This is often not mentioned.Check that all light sources in the apparatus (except guide lights and warning lights) are real lasers.
3.For oral work and wound healing HeNe and GaAIAs are the most common types and GaAIAs as the most versatile.Sterilizeable probes are normally only available for GaAIAs lasers.For injuries to joints, vertebrae, the back, and muscles, that is, for the treatment of more deep-lying problems, the GAAs laser is the best documented.For veterinary work, laser designed so that the light can pass through the coat, and penetrate to the desired depth is best.For superficial tendon and muscle attachments, the required depth can be reached with the GaAIAs laser.Many companies have only one type of laser, such as a GaAIAs, and the salesman will naturally tell you that it is the best model for everything, and that it is irrelevant which type of laser is used.However, research tells quite a different story.
4.Size, colour, shape, appearance and price vary a great deal from manufacturer to manufacturer.Because a piece of equipment is large, it does not necessarily follow that its medical efficacy is high, or vice versa.The most important factor is the dosage that enters the tissue.Make sure the laser you buy is designed so that the light actually enters the tissue.Ask the salesman: How is the dosage measured? What kind of dosage is too high, and what is too low?
5.Many companies which import lasers have deficient knowledge in terms of medicine, laser physics, and technology.In fact, there are many examples of companies that have gone bankrupt.If a piece of equipment is faulty, it may have to be sent to the country of manufacture for repair.How long would you be without your equipment in such a case, and what would it cost to repair?Can the importer document his expertise? Who can you speak to who has used the apparatus in question for a long period of time? Is there a well-known professional who uses this make?What does it cost to change the laser diode or laser tube, for example, after the guarantee has expired?Can you get written confirmation of this? Try to get a list of references.
6.The difference between a colourful brochure and reality is often considerable.There are examples of brochures which describe the output ten times that which the equipment actually provides.How can you find out the real performance of the equipment (e.g. its output)?Are the measurement results from an independent authority? Is it possible to borrow an apparatus in order to measure its performance?Is there an intensity meter on the apparatus which can measure what is emitted and show it in figures? It is not enough simply to have a light indicator.
7.Some dealers know that their products are sub-standard.This can often be seen by the fact that they are anxious to get the customer to sign a contract.If a product is good, the dealer will have no doubts about selling it on sale-or-return basis, with written confirmation of this.What happens if the medical effects are not as promised?Is it possible to get a written guarantee of sale-or-return? In most countries, therapy lasers must be approved.The approval certificate shows the laser type and the class to which the instrument belongs, e.g. laser class 3B.There is also a certificate number.A laser which is not approved is either not a laser, or is being sold illegally.
8.Many companies organize courses and “training” events of markedly varying quality.A serious importer or manufacturer takes pains to ensure that his equipment is used in a qualified way, and makes sure that the customer receives some training in its use.What are the instructor’s background and qualifications?Has he or she published anything? Is there a course description? What does the training material cost?Is a training course included in the cost of the equipment? Is the training material included? Is it possible to buy the training material only?
9.Development is going on at a fast pace.Suddenly, you have out-of-date laser equipment and a new and perhaps more efficient type of laser comes onto the market.What happens if your laser becomes outmoded?Do you have to buy a new laser, or can your equipment be updated with future components lasers?
How do I compute the dosage for a laser treatment?
Typically, clinicians calculate the Energy Density (E.D.) in J/cm2 for a specific treatment using the following equation:
E.D. (J/cm2) = (Average Power (Watts) x Time (seconds)) / Surface Area (cm2)
Hence;
Time (seconds) = (E.D. (J/cm2) x Surface Area (cm2)) / Average Power (Watts)
The surface area is the beam spot size of the laser device used. Since the beam spot size in true lasers is usually quite small, typical E.D.’s for treatment protocols are in the hundreds of J/cm2. Some manufacturers of weaker power devices will advertise use of E.D’s less than 10 in order to advertise shorter treatment times.
Since many clinicians use the grid technique and direct contact on the skin, the surface area in the above equation should be 1 cm2. This makes calculating treatment time very straightforward. It also becomes evident that devices with higher average powers will take less time to obtain the same density.
What factors should I consider in calculating the appropriate dose?
Since laser energy is absorbed by water, hemoglobin and melanin, different people will require different dosages so that the target tissue of interest obtains the desired energy density.The depths of the target will also play a major part in this decision. Since light energy will be absorbed by other tissues that lie between the target tissue and the skin surface, one should increase the dose to obtain the desired dosage at the target site.In order to bio-stimulate the tissue, light must reach the target in a sufficient dose otherwise bio-stimulation will not occur.