| What
is a Laser ? A Laser is an amplifier of
light. The letters LASER are an acronym, signifying “
light amplification by stimulated emission of radiation
“.
What are
the properties of laser light ?
There are two properties :
1. Monochromatic. Laser light has a very narrow bandwidth.
2. Coherent. The light is well ordered and synchronous.
Like a musical instrument holding a single note, a laser
emits pure light at a specific wavelength rather than over
the wide spectral distribution of most light sources. Laser
light is extremely well-organized. Photons emitted from
a laser source have been compared to soldiers marching in
precise order. We call this coherence; it is an exclusive
property of lasers.
Two common misconceptions about lasers are that 1. beams
are always parallel and 2. all lasers are high-powered.
Therapeutic lasers are often designed with divergent beams
as a safety precaution, and they may operate at very low
levels of power.
What is low-level
laser therapy and who can use it ?
LLLT is the therapeutic application of laser light at low
intensity. It is commonly performed using lasers in the
near infrared or visible, red portions of the spectrum.
As a contrast to surgical lasers which usually have output
of 500 milliwatts or less and are classified by the FDA
as non-significant risk devices.
What are
the effects of LLLT ?
The physiological effects of laser light at low intensity
are not completely understood, but what is known from a
biochemical model is often summarized in terms of three
main effects :
• Bio-stimulation / Tissue regeneration
• Anti-inflammatory
• Analgesic
LLLT increases metabolism at the cellular level, causing
accelerated ATP production; protein synthesis ; DNA and
RNA formation; and many positive markers. At the tissue
level, circulation increases during and after the administration
of LLLT ; new blood and lymphatic vessels are formed; and
collagen synthesis is enhanced. The biochemical model attributes
pain relief to a host of factors, including elevated endorphins
and acetylcholine; nerve blockade; decreased syhthesis of
bradykinin; decreased release of histamine; and increased
microcirculation to correct ischemia and acidosis.
How does
one integrate LLLT into Oriental medicine ?
Just as depth of insertion and technique alter the effects
of traditional needling, so may wavelength, power and pulsing
modify the energetic response by the body of LLLT. Light
is an energetic bias like needles, electrical stimulation
and herbs. The body’s response is activated by differences.
Are there
risks associated with LLLT ?
There is no destruction of tissue and relatively little
risk associated with low power lasers.
While low level lasers are comparatively safe, there is
a potential for damage to the eye. The beam in LLLT, if
directed through the lens of the eye, could burn the retina.
In over 30 years of research and clinical practice, however,
an adverse reaction of this or any type has never been documented.
To operate a laser safely, it is important to understand
the nature of one’s equipment. The power, wavelength
and characteristics of the laser beam (its divergence, convergence
or parallel nature ) all influence the level or risk. Knowledge
may be even more valuable than protective goggles.
Obviously, a high power laser is much riskier than a weak
one. An infrared laser poses a greater risk than a visible,
red laser with the same power and beam characteristics because
the light is invisible and therefore does not promote a
blink response.
What can
Laser Therapy treat ?
Therapeutic applications which have shown promising results
based on studies include :
Acne. Arthritis. Back Pain. Carpal Tunnel Syndrome. Cerebral
Palsy. Dental Applications. Fibromyalgia. Hearing Disorders.
Herpes. Hypertension. Lymphedema. Maxillofacial Disorders.
Meniere’s Disease. Nerve regeneration. Neuralgia.
Neuropathy. Pain (Musculoskeletal, Myofascial, Nerve ).
Peyronie’s Disease. Prostatitis. Sinusitis. Scars.
Skin Disorders. Sjoegren’s Syndrome. Sports Injuries.
Tendonitis. Tinnitus. Wound Healing.
Is there a
physical difference between laser and LED /or other light
sources ?
Yes there is, Laser light has unique physical properties,
that no ordinary light has. This is the key to why laser
light is so effective compared to other kinds of light in
healing.
Is Laser Therapy
scientifically well documented ?
Basicly yes. There are more than 100 double-blind positive
studies confiming the clinical effect of LLLT. More than
2500 research reports are published. Looking at the limited
LLLT dental literature alone (370 studies), more than 90%
of these studies do verify the clinical value of laser therapy.
But I’ve
heard that there’re dozens of studies failing to find
any effect of LLLT?
That is true. But you cannot just take any laser and irradiate
for any length of time and using any technique. A closer
look at the majority of the negative studies will reveal
serious flaws. But LLLT will naturally not work on anything.
Competent research certainly has failed to demonstrate effect
in several indications. However, as with any treatment,
it is a matter of dosage, diagnosis, treatment technique
and individual reaction.
How deep into
the tissue can a laser penetrate ?
The depth of penetration of laser light depends on the
light’s wavelength, on whether the laser is super-pulsed,
and on the power output, but also on the technical design
on the apparatus and the treatment technique used. A laser
designed for the treatment of humans is rarely suitable
for treating animals with fur. There are, in fact, lasers
specially made for this purpose. The special design feature
here is that the laser diode(s) obtrude from the treatment
probe rather like the teeth on a comb. By delving between
the animal’s “hair”, the laser diode’s
glass surface comes in contact with the skin and all the
light from the laser is “forced” into the tissue.
A factor of importance here is the compressive removal
of blood in the target tissue. When you press lightly with
a laser probe against skin, the blood flows to the sides,
ao that the tissue right in front of the probe ( and some
distance into the tissue ) is fairly empty of blood. As
the haemoglobin in the blood is responsible for most of
the absorption, this mechanical removal of the blood greatly
increases the depth of penetration of the laser light.
It is of no importance whether the light from a laser probe,
held in contact with skin is a parallel beam or not. There
is no exact limit with respect to the penetration of the
light. The light gets weaker and weaker the further from
the surface it penetrates. There is , however, a limit at
which the light intensity is so low that no biological effect
of the light can be registered. This limit, where the effect
ceases, is called the greatest active depth. In addition
to the factors mentioned above, this depth is also contingent
on tissue type, pigmentation, and dirt on the skin. It is
worth noting that laser light can even penetrate bone (
as well as it can penetrate muscle tissue ). Fat tissue
is more transparent than muscle tissue.
For example: a HeNe Laser with a power output of 3.5mW
has a greatest active depth of 6-8 mm depending on the type
of tissue involved. A HeNe laser with an output of 7mW has
a greatest active depth of 8-10 mm. a GaAIAs probe of some
strength has a penetration of 35mm with a 55mm lateral spread.
A GaAs laser has a greatest active depth of between 20 and
30 mm ( sometimes down to 40-50 mm), depending on its peak
pulse output (around a thousand time greater than its average
power output). If you are working in direct contact with
the skin, and press the probe against the skin, then the
greatest active depth will be achieved.
Can LLLT
cause cancer ?
The answer is no. no mutational effects have been observed
resulting from light with wavelengths in the red or infra-red
range and of doses used within LLLT. But what happens if
I treat someone who has cancer and is unaware of it ? Can
the cancer’s growth be stimulated? The effects of
LLLT on cancer cells in vitro have been studied, and it
was observed that they can be stimulated by laser light.
However, with respect to a cancer in vivo, the situation
is rather different. Experiments on rats have shown that
small tumours treated with LLLT can recede and completely
disappear, although laser treatment had no effect on tumours
over a certain size. It is probably the local immune system
which is stimulated more than the tumour. The situation
is the same for bacteria and virus in culture. These are
stimulated in vitro by laser light in certain doses, while
a bacterial or viral infection is cured much quicker after
the treatment with LLLT.
What happens
if I use a too high dose ?
You will have a biosuppressive effect. That means that,
for instance, the healing of a wound will take longer time
than normally. Very high doses on healthy tissues will not
damage them.
LASER as
a Therapeutic tool
Lasers have been used safely as a therapeutic tool for
over 30 years. Laser Therapy (LT) differs from the use of
lasers in surgery due to a lower output power and reduced
energy density. Instead of ablating tissue, LT stimulates
cellular activity that improves the speed and quality of
healing. In over 1800 publications worldwide, LT has demonstrated
its non-invasive, non-toxic quality, and its ability to
augment and in some cases, replace, pharmaceuticals and
surgical intervention. LT is most often used as a primary
medical treatment, but is also effective as a complement
to other modalities, such as needle acupuncture and chiropractic
adjustment. Acupuncturists, Chiropractors, Physical Therapists,
Dentists, Osteopaths and M.D’s currently use LT for
a variety of problems; including the treatment of acute
pain and chronic degenerative conditions, improving the
speed and quality of wound healing, and for muscle, tendon
and ligament injuries.
How is Laser
Therapy Administered ?
LT is usually conducted in an outpatient clinic setting
or professional Beauty Salon, and requires no unusual equipment
or precautions except that safety glasses are normally recommended
for the patient and therapist.
The laser is held against the skin in a contact mode (OSHIRO),
applying the maximum amount of laser light to the area of
consideration. Many therapists recommend applying light
to firm pressure to the area to distress the underlying
blood vessels and tissue to improve the penetration of the
energy. The laser is applied at a given power output for
a specified period of time, to deliver the proper amount
of laser energy, measured in joules. Dosages can range from
1 joule up to 30 or more, depending upon the condition being
treated and the schedule of treatments. A wavelength is
chosen which meets the absorption requirements of the condition,
with wounds and aesthetic conditions benefiting from higher
absorption (lower wavelengths). Normally , multiple treatments
are needed to resolve chronic conditions and injuries. Laser
can be directed to acupuncture points,
trigger points, nerve endings and directly to the specific
injury. Recent findings conclude that, with few exceptions,
patients do better when treatment begins as quickly as possible.
Veqish
Spa ~ If you’ve had a choice….. you’d
live a healthy life. |
