Cold Laser and Light Therapy
Transcript of Cold Laser and Light Therapy
Cold Laser
and Light Therapy
By:
Dr. Wendy L.C. Varish, DC, FACO, CCSP, CCOHC
Laser and Light Therapy
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Clinical Applications of
Light Therapy and Cold Laser
in Chiropractic
Wendy Varish, DC, FACO, CCSP,
CCOHC
“Live as if you were to die tomorrow. Learn as if you were to live forever.”
-Mahatma Gandhi
Wendy Varish, DC, FACO, CCSP, CCOHC
Howards Grove Chiropractic
516 S. Wisconsin Drive
Howards Grove, WI 53083
(920) 565-3922 fax (920) 565-2142
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WISCONSIN CT
CHIROPRACTIC TECHNICIAN
STATE REQUIREMENTS
www.dsps.wi.gov
Delegation by Chiropractors
• Chir 10.05 Physiological therapeutics.
• A chiropractor may delegate the performance of patient services through physiological therapeutics that include but are not limited to heat, cold, light, air, water, sound, electricity, massage, and physical exercise with and without assistive devices to an unlicensed person only if the delegation is consistent with s. Chir 10.02 and the unlicensed person has adequate training, education and experience to perform the delegated function to minimally acceptable chiropractic standards.
Delegation Rules• 446.02(7)(d)2.
2. Beginning on July 1, 2010, a chiropractor may
delegate adjunctive services only to a chiropractic
technologist.
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Wisconsin State Statutes:• 446.01 Definitions. In this chapter:
• (1d) “Adjunctive services” means services that are
preparatory or complementary to the practice of
chiropractic. “Adjunctive services” includes all of the
following:
• (a) The taking and preparation of preliminary patient
histories, as defined by the examining board by rule.
• (b) Providing physiotherapy treatment, as defined by the
examining board by rule.
446.026 Regulation of chiropractic technicians:
• (1) (a) No person may provide adjunctive services unless the person is a chiropractic technician and is under the direct, on−premises supervision of a chiropractor licensed under this chapter.
• Chir 10.02
(2) The chiropractor exercises direct supervision of the unlicensed person performing the delegated service.
Chir 10.01 Definitions
(3) “Unlicensed person” means a person who does not possess a valid license to practice chiropractic in this state pursuant to ch.446
• (b) Except as provided in s. 446.025 (1) (b), no person may designate himself or herself as a “chiropractic technician” or “chiropractor technician,” use or assume the title “chiropractic technician” or “chiropractor technician” or any title that includes “chiropractic technician” or “chiropractor technician,” append to the person’s name the letters “C.T.,” or use any other title or designation that represents or implies that he or she is a chiropractic technician unless the person is certified by the examining board under this section.
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Prohibited Practices
• Chir 12.06 Prohibited practices. (1) A
chiropractor shall not delegate to any
chiropractic assistant or other person any
recommendations, analysis, advice,
consultation or dispensing with respect to
vitamins, herbs, or nutritional supplements.
Nothing in this subsection may be construed
to prevent chiropractic assistants or
administrative employees from processing
sales of vitamins, herbs, or nutritional
supplements.
Chiropractic Technician - Licensing
• Beginning July 1, 2010 an applicant must hold a certification as a chiropractic technician to continue to provide adjunctive services delegated by a Wisconsin Licensed Chiropractor.
• (The process of granting a credential to persons currently practicing in the field, based on their past training and experience, is referred to as Grandfathering-no longer applicable.) Persons performing services that will fall within the new scope of practice for chiropractic technicians may apply for a credential by meeting the requirements of the State.
http://dsps.wi.gov
How to Apply for CT
Certificate1). Complete and submit appropriate application form #2884 and fee, including all documentation.
Application for Chiropractic Technician form #2884
2). Certificate of Completion from an approved course provider in relation to the adjunctive services provided by a Chiropractic Technician. (Provide either a copy of Certificate of Completion or Course Provider form #2865)
3). Determination to grant credential is made.Common Denial Reason:
Does not meet criteria above. Convictions of crimes or pending charges may be grounds for denial of license if the circumstances of the conviction or charge are substantially related to professional practice.
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CT Certification Renewal
• Biennial Renewal Due:
• Per Wisconsin State Statutes 440.08 (2), the required renewal date for the Chiropractic Technician credential is 12/14/even years.
• At this time, 6 hours of approved continuing education (CE) required for renewal
• Should you receive your initial credential in the months leading up to this date, you are still required to renew your license by the statutorily defined date. (but will not need the 6 CE credits until the next renewal).
What is Light??
• Light is actually Radiation:
– The process by which energy in various forms travels through space.
What is Light?
• Light (radiation) is a form of energy which behaves as both a particle and also a wave.
• Light particles are known as photons.• Photons are the basic units light. (Just as atoms
are the basic units of matter)
• Photons travel at 186,000 miles per second (300,000km)– faster than any other known particle.
• Energy is emitted and transmitted in the form of particles and waves
• Light energy is absorbed by matter.
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Electric and Magnetic
Properties of Light Waves
Because of the ability to exist as both a particle and wave, light
waves are considered electromagnetic in nature; they have
both electrical and magnetic properties.
What is Light??
• Terms used to Describe Light and Energy:
– Wavelength (width)
– Amplitude (Intensity - how high)
– Velocity (speed of light)
– Frequency (Rate = speed of light / wavelength)
Major Concepts of Light Therapy
• The sun emits energy in a broad spectrum
called the electromagnetic spectrum.
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Sunlight is composed of every color.
When sunlight passes through a prism, the
visible light is separated into a rainbow of
different colors.
However, this prism is also separating forms of
radiant energy that is not visible to our eyes .
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• The Sun emits almost every wavelength of
light, even light our eyes can't see.
• Sunlight your eyes CANNOT see(invisible)
• radio
• microwaves
• infrared
• ultraviolet
• X-Rays
• Gamma Rays
Electromagnetic Spectrum
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Light and Energy
• Velocity (speed of light = 300 million meters per second)
• Wavelength (width)
– Defined as the distance between the peak of one wave
and the peak of the next
• Frequency
– Defined as the number of oscillations or vibrations
occurring in 1 second
– Expressed in hertz (Hz)
– (Frequency = speed of light / wavelength)
• Amplitude (intensity – how high)
Velocity
• Electromagnetic radiation always travels at
the speed of light. (~186,282 miles/sec or
~300,000 km/sec)
• For practical purposes we can say that
radio waves always travel at the speed of
light.
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Wavelength, Frequency, Amplitude
t
Period
Frequency = number of waves per second
Wavelength
The shorter the wavelength, the higher the
frequency of the radiation.
The higher the frequency, the greater the
energy of the wave
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• Ultraviolet light -- 100-380nm
– Considered ionizing radiation
– This penetrates and breaks covalent bonds
• Visible light approximately 380-740 nm
• Infrared light – approximately 740-1000 nm
– Far infrared to approximately 10,000 nm
Major Concepts of Light Therapy
• Radiation (including visible light in the 380-740nm
wavelengths), is made up of individual packets of
energy called photons.
• The energy of a photon relates to its wavelength:
– Short wavelength photons are very energetic
– Long wavelength photons have lower energy
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Effects of Photon Energy
• The photons in the UV range (200-400nm)
creates chemical excitation within the cells,
which leads to alteration of DNA and RNA
synthesis.
• The photons in the red range (~630-660nm) are
strong enough to alter the shape of certain
receptor proteins in the mitochondrial cell
membrane …. But weak enough not to damage
the cell (including its DNA, enzymes, proteins,
and lipids).
Mitochondria
• Power house of the cell
• Involved with cellular respiration; cell division &
growth; cell differentiation; cell signaling; cell death
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Cytochrome c
• Cytochrome c is highly
soluble protein found in the
intermembrane space of
the mitochondria
• Plays a vital role in cellular
oxidation in both plants and
animals.
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Cytochrome c
• It is an essential
component of the
electron transport chain,
where it carries one
electron.
• It is capable of
undergoing oxidation and
reduction, but it does not
bind oxygen.
The main function of Cytochrome c in cellular
respiration is to transport electrons from
cytochrome c reductase (Complex III) to
cytochrome oxidase (Complex IV).
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• Cytochrome c is suspected to be the functional
complex in Low Level Light Therapy.
• In LLLT, red light and some near infra-red
wavelengths penetrate tissue and appear
capable of increasing activity of cytochrome c
• Increasing the activity of cytochrome c
increases the metabolic activity of the cell and
frees up more energy for the cells to repair the
tissue.
• Silveira PC, Streck EL, Pinho RA. (2005). "Cellular effects of low power laser therapy
can be mediated by nitric oxide.". Lasers Surg Med. 36 (4): 307–14.
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Cytochrome c Oxidase
Cytochrome C Oxidase
It is proposed that Cytochrome C Oxidase (Cox) is
the primary photoacceptor for the red to near IR
range in mammalian cells (Karu and Kolyakov 2005).
Nitric Oxide and Cox
• In stressed or hypoxic cells, the mitochondria produce
excess Nitric Oxide. (Brown 2001).
• The excess Nitric Oxide bond to Cox (Cytochrome oxidase).
This will competitively displace oxygen and will inhibit
respiration.
• After LLLT, increased nitric oxide (NO) concentrations can
be measured in cell cultures and in animals.
• It has been proposed that LLLT works by photodissociating
NO from Cox, thereby reversing the mitochondrial inhibition
of respiration due to excessive NO binding (Lane 2006).
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When LLLT (red light) is applied, Nitric Oxide is released from its
binding to heme iron and copper centers in cytochrome c oxidase.
Oxygen is allowed to rebind to these sites.
Respiration is restored and leads to increased ATP synthesis
Phototherapy
• Phototherapy is the “Application of light to stimulate” -
-visible red and NIR light absorbed by Cytochrome c
oxidase
• Karu (2010) speculates that photoirradiation may
intensify the transfer of electrons within cytochrome c
oxidase by making more electrons available
• Karu TI et al., (2008) Photomedicine and Laser Surgery 26(6):593-599.
• Karu TI. (2010) IUBMB Life 62(8) 607-610.
• Silveira PCL, et al., (2009) Journal of Photochemistry and Photobiology B: Biology 95:89-92.
Therapeutic Application of Red
light at 636 nm…..
• Stimulates stressed cells
• Increases the mitochondrial membrane potential
• Increases activity of mitochondrial complex IV
(cytochrome c oxidase)
• Increases ATP and cAMP
• Directs cells into a cell survival pathway
• Restores homeostasis to cells
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Therapeutic Window of Light
Major Concepts of Light Therapy
• The 635nm photon wavelength has just
the right amount of energy to stimulate
mitochondrial membrane proteins.
• This results in an increase of cellular
energy ATP.
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Major Concepts of Light Therapy
• Small amounts of increased cellular energy
(ATP) have significant influences on how the cell
functions.
• Since the nervous system uses the greatest
amount of ATP energy, the greatest
improvement with laser/light therapy is seen in
neurological function.
To Summarize…
• In a clinical setting, we use radiation in the
red (~635-740nm) and infrared (~740-
1000nm) wavelengths
• Red and infrared are on the opposite side
of the visible spectrum as ultraviolet
• Ultraviolet (and smaller wavelengths) are
considered ionizing radiation and can be
damaging
• Red and Infrared (when applied correctly)
are therapeutically beneficial on a cellular
level!
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Clinical Benefits
of
Light Therapy
3 Basic Effects of Light Therapy
• Tissue Repair
• Acceleration of Inflammation
• Pain Control
Effects of Light Therapy
• Speeds up inflammation (i.e. the HEALING
process
• Speeds up wound healing / soft tissue repair
• Increases microcirculation
• Decreases pain
• Muscle relaxation
• Increases range of motion
• Increases lymph drainage – improves immune
system function
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Beneficial tissue effects of LLLT can include
almost all the tissues and organs of the body.
APPROVED CLAIMS FOR INFRARED THERAPY
“Infrared therapy emits energy for temporary increase in local
blood circulation, temporary relief of minor muscle and joint aches,
pain and stiffness and relaxation of muscles; for muscle spasms,
and minor pain and stiffness associated with arthritis.”
Laser therapy effective for acute and
chronic neck pain…
(Reuters Health, 11-12-2009) –Meta-analysis by Dr. Roberta T. Chow and
colleagues from the University of Sydney, Australia
• 16 randomized controlled trials (with 820
patients) that compared LLLT with placebo or
with active control as a treatment for acute or
chronic neck pain.
• Reports that low-level laser therapy (LLLT)
provides rapid relief of acute neck pain as well
as sustained improvements in chronic neck pain
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Chow, cont.: 11/13/2009 Online issue of The Lancet…
• Data from two of the trials showed that LLLT was
69% more likely than placebo to improve acute neck
pain.
• In five trials looking at chronic neck, LLLT was
roughly four times more likely than placebo to
improve pain.
• In 11 trials that evaluated changes in visual
analogue scale, LLLT was associated with a mean
drop in pain intensity of 19.86 mm.
• Data from seven trials, with up to 22 weeks of
follow-up, showed persistent pain relief for up to 6
months, with a mean reduction in pain intensity of
22.07 mm.
Infrared therapy for chronic low back
pain: A randomized, controlled trialGeorge D Gale, MBBS FRCA FRCPC DAAPM, Peter J Rothbart, MD FRCPC, and Ye Li Pain
Research & Management. 2006 Autumn; 11(3): 193–196
OBJECTIVE: The objective of the study was to assess the degree of pain
relief obtained by applying infrared (IR) energy to the low back in patients
with chronic, intractable low back pain.
METHODS: 39 patients with chronic LBP of > 6 yrs duration were
recruited from patients attending the Rothbart Pain Management Clinic,
North York, Ontario. They were randomly assigned to IR therapy or
placebo treatment. 21 patients received IR therapy (800-1200nm) and 18
received placebo therapy for 7 wks (1x/wk). The principle measure of
outcome was pain rated on the numerical rating scale (NRS). The pain
was assessed overall, then rotating and bending in different directions.
RESULTS: The mean NRS scores in the tx group fell from 6.9 of 10 to 3
of 10. The mean NRS in the placebo group fell from 7.4 of 10 to 6 of 10.
CONCLUSION: The IR therapy unit used was demonstrated to be
effective in reducing chronic low back pain, and no adverse effects were
observed.
MECHANISMS
OF
LIGHT THERAPY
How does it work?
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Clinical Phototherapy
Defined as....
• The delivery of the optimum amount of
photon energy to the diseased tissue or
tissues with the intention of modulating the
process of inflammation-repair and
through influencing the neuroimmune
endocrine system
Terms
• Photochemistry
– How light energy is absorbed by the tissue.
• Photobiology
– How light energy is used by tissue.
1st Law of Photochemistry/Photophysiology:
Light must be absorbed for Photochemistry or
Photophysics to occur
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Photochemistry of Light Therapy
• “So far, what we see in patients and what we see in laboratory cell cultures, all point to one conclusion. The near-infrared light emitted by these LEDs seems to be perfect for increasing energy inside cells.
• LEDs have a similar physiological effect on human cells as they do on plant cells. LEDs stimulate cytochromes in the body that increase the energy metabolism of cells. Cytochromes are part of the “electron transport chain” that converts sugar into instant energy required by the body to perform all of its actions, such as raising a finger or healing a wound.”
Light Emitting Diodes Aid in Wound Healing—
Harry T. Whelan, MD, Professor of Neurology,
Medical College of Wisconsin
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• Cytochrome c oxidase is
the terminal enzyme in the
electron transfer chain.
• It reduces oxygen to water
and utilizes the excess
energy to translocate
protons across the
mitochondrial membrane.
• Cytochrome c oxidase is
the enzyme responsible for
over 90% of the oxygen
consumption by living
organisms in the biosphere.
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• The proton gradient across the
mitochondrial membrane is increased
by red light stimulation.
• Cytochrome c oxidase:
– photoreceptive site
– red light excites electron states that
drive increased ATP production
Tissue RepairLaboratory and clinical studies have proven Light Therapy to be effective for tissue repair related to:
Skin wounds
Ulcers
Ligament tears
Tendon Ruptures
Scars
Burns
Bone and Dental Tissue
How do various colors
(wavelengths) of light help
with Tissue Repair?
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Therapeutic Effects of Different
Wavelengths of Light
• Red visible light (approximately 633nm)
will affect the mitochondria
• Near Infrared Radiation does not affect the
mitochondria, but does affect the cellular
membrane and stimulates cell proliferation
• Stimulation of the mitochondria within the cell
with RED light will effectively increase ATP
(energy) production from 2 ATP up to 18 ATP.
This is a 9-fold increase in cell energy !!
Imagine what YOU could do with 9x more energy!
Cell Injury
• When a cell is injured, the cell wants to “shut
down”.
• Think of this as a city that has been
devastated with a hurricane…
– The city shuts down
– Curfews are set
– People/workers are not allowed in or out….
– Supply lines for food, water, cleaning supplies are
limited
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• In order to start the repair process
following a hurricane (or other natural
disaster, etc.)…
• The city must be re-opened so that
supplies and rescue workers can come in
and start the clean-up and repair
Following Cell Injury…
• In order to speed up healing, it makes
sense to increase the cell permeability.
• Near INFRARED light will increase cell
permeability.
• This, in effect, will speed up the
inflammation process.
• In addition…Red and Infrared Light therapy
increases microcirculation (not vasodilation).
This also helps with wound healing.
• This is comparable to making new roads or
detours so that supplies and workers can
access damaged areas.
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Photo-
chemistry
of Light
Therapy
Absorption in the Mitochondria
and Cell Membrane by Chromophores
Elevation of ATP synthesis (Ca2+ and the respiratory chain involved);
Increases the energy in the cell.
DNA & RNA synthesis; protein synthesis;
mitosis and cell proliferation
Light (Photons) Applied to Tissue
Tissue Repair
Photobiology of Light Therapy
Light Therapy Promotes:• Inflammation (speeds up the process)
• Fibroplasia (increase in size and number of fibroblasts)
• Neoangiogenesis (formation of new blood vessels)
• Collagen Synthesis
Photobiology of Light Therapy
“Laser radiation at 633 nm has been shown
to stimulate collagen synthesis in cutaneous
wounds by enhancing the synthesis of Type I
and Type II procollagen mRNA levels.”
The Photobiological Basis of Low Level Laser Radiation Therapy—
Kendric C. Smith, Department of Radiation Oncology,
Stanford University School of Medicine
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Photobiology
“Photoactivation of Enzymes—The light activation of enzymes is one of
the fastest growing fields of photobiology, and several reviews on this
subject have appeared. The importance of the light activation of enzymes
is that enzymes are catalysts. In principle, one photon can activate one
enzyme molecule, which in turn can process many thousands of
substrate molecules. This provides a huge amplification factor for
initiating a biological response with light. This remarkable amplification
factor may be the explanation for why low level laser radiation therapy is
effective. If the effect of one photon can be amplified biologically, then one
does not need a lot of photons to produce an effect. One just needs to
find the proper wavelength of light to stimulate the proper enzyme,
which in turn will stimulate the beneficial therapeutic effect.”
The Photobiological Basis of Low Level Laser Radiation Therapy—
Kendric C. Smith, Department of Radiation Oncology,
Stanford University School of Medicine
The Inflammatory CycleInjury to tissue
Hematoma
Platelets
Fibroblasts
LeukocytesSerotonin released
Action potential decreases –nerves fire easier and the area is more sensitive
Bradykinin is released
Prostaglandins are released
Formation of new
blood vessels
Partial pressure of oxygen
increases in tissue
Fibroplasia
Collagen Synthesis
Tissue remodeling and
contraction
Starts around Day 3
Can take up to 100 days for tissue to mature completely
Phases of Wound Healing
Response
Time in Days
1 3 10 30
100
InflammationProliferation Maturation
Collagen Accumulation
Wound Contraction
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Phases of Wound Healing
Response
Time in Days
1 3 10 30100
Inflammation-
speeds up and is not as severe
Proliferation –cell
healing occurs sooner and is faster
Maturation
Collagen Accumulation
Wound Contraction-occurs sooner
Remodeling
Photobiology of
Light Therapy
Neoangiogenesis(formation of
new blood vessels)
Injury
Collagen Synthesis
PlateletsMast cellsMonocytes
MacrophagesLymphocytes(Released factors:
HistaminePDGF, FGF,
Leucotrienes, &Other growth factors
Fibroplasia(Proliferation of fibroblasts)
Fibroblasts
New Collagen Tissue
Neurons
Nerve Tissue
Hematoma (Blood Clot)
Fibroblasts
LIGHT THERAPY FOR
PAIN RELIEF
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Pain Control
Evidence suggests beneficial effects for many pain conditions
including, but not limited to, the following:
Carpal Tunnel Syndrome
Neck and Back Pain
Acute Phase Herpes Zoster [Shingles]
Post-Herpetic Neuralgia
How does Light Therapy Affect Pain?
• Most common theories involve changing the
cell permeability and increasing the action
potential.
• This results in
– increased endorphin release
– decreased bradykinin
– decreased C fiber activity
– blocking of Prostaglandin E1 and Bradykinin B in
plasma fibrin levels
• By increasing the Action Potential, the pain fiber
nerves are less sensitive and not as easily
stimulated
• We then are less likely to “feel” as much pain
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Compared to “real
life”…. Think of the
Action Potential as the
Media & News reports.
If we are unaware of the tragedy (or pain),
then we really don’t think about it and are
unaffected by it in our daily lives.
There are three main neurotransmitters
involved in generating the action potential:
Glutamate – associated with acute pain. Appears to be
the dominant neurotransmitter when the threshold of
pain is first crossed.
Substance P –peptide that contains 11 amino acids and
is released by C fibers. It is generally associated with
intense, persistent, chronic pain, and used to relay pain
messages leading to the spinal cord and brain.
Glycine – this is involved in suppressing the
transmission of pain signals in the dorsal root ganglion.
Pain control due to increasing the Action Potential via:
-increased endorphin release
-decreased bradykinin
-decreased C fiber activity & production of Substance P
-blocking of Prostaglandin E1 and Bradykinin B in plasma fibrin levels
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Light is scattered into tissue
Areas of high and low light differences
produce temperature and pressure
differences across the cell membrane
Cell permeability is affected which affects
the mitochondrial membrane
Increased receptor activity on the cell
membrane
Bradykinin is reduced
Endorphins are produced
Pain C-fiber activity is decreased
Sensitivity is decreased because
the Action Potential is increased
The Inflammatory CycleInjury to tissue
Hematoma
Platelets
Fibroblasts
LeukocytesSerotonin released
Action potential decreases –nerves fire easier and the area is more sensitive
Bradykinin is released
Prostaglandins are released
Formation of new
blood vessels
Partial pressure of oxygen
increases in tissue
Fibroplasia
Collagen Synthesis
Tissue remodeling and
contraction
Starts around Day 3
Can take up to 100 days for tissue to mature completely
Terms
• Photochemistry
– How light energy is absorbed by the tissue.
• Photobiology
– How light energy is used by tissue.
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Effects of Light Therapy
Reviewed…
• Increases cell permeability
• Increases cell energy
• Increases cell division and repair
• Increases microcirculation
• Basically… it helps the healing of cells
quicker with less swelling and less
scarring. The cells heal faster and
stronger!
• "This technology may be the answer for problem wounds
that are slow to heal....diabetic skin ulcers and other
wounds in mice healed much faster when exposed to the
special LEDs in the lab. Laboratory research has shown
that the LEDs also grow human muscle and skin cells up
to five times faster than normal...."
• "Light close to and in the near-infrared range has
documented benefits for promoting wound healing in
human and animals. "http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pub
med&dopt=Abstract&list_uids=11568632
• "Near-infrared irradiation potentially enhances the wound
healing process, presumably by its biostimulatory effects." http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pub
med&list_uids=11722751
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Treatment
Parameters
Basic Terminology
• PowerMeasured in Watts or milliwatts.
MILLIWATT (mW) = one thousandth of a watt.
Power determines length of treatment
• WavelengthNANOMETER (nm) = one billionth of a meter.
Wavelength determines two things - depth of penetration & light absorption
• EnergyEnergy is a function of Power and Time
JOULE (J) = Power (W) x Time (s)Joule / cm² = 1w x 1 sec / 1 cm²
Energy is the preferred unit for reporting doses of treatment
3 Parameters
for Light Therapy
1. Power
2. Wavelength for Light Absorption
3. Wavelength for Depth of Penetration
» Wavelength is measured in nanometers (nm) which is one billionth of a meter.
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Therapeutic Effect
Depth of Penetration
Light Absorption
Power
#1- PowerDetermines
Treatment Time
Power
• Power is measured in Watts or milliwatts (mW).
• One milliwatt (mW) = one thousandth of a Watt
• Power determines Treatment Time
Power
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TR
EA
TM
EN
T T
IME
(seco
nd
s)
POWER (mW)
300 sec
600 mW0
30
60
90
120
150
180
210
240
270
60 120 180 240 300 360 420 480 540
There is an inverse relationship between power
and treatment time. To achieve a specified dose,
Treatment Time decreases as Power increases.
Comparison of
Treatment Times
EDCBADynatronics
Seco
nd
s
Light Absorption
#2- WavelengthDetermines
Light Absorption
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Effects of Different Types
of Light Therapy
• Visible light (approximately 633nm) will
affect the mitochondria
• Near Infrared Radiation does not affect the
mitochondria, but does affect the cellular
membrane and stimulates cell proliferation
Photochemistry of Light Therapy
“The first law of photochemistry states that light must be
absorbed before photochemistry can occur. An absorption
spectrum is a plot of the probability that light of a given
wavelength will be absorbed by the system under
investigation.”
The Photobiological Basis of Low Level Laser Radiation Therapy
Kendric C. Smith, Department of Radiation Oncology,
Stanford University School of Medicine
Electromagnetic Spectrum
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Therapeutic Window of Light
Cluster Probe using Multiple Wavelengths -
660nm & 880nm
"Growth factor production and collagen synthesis may be
improved at wavelengths of 660-680 nm and stimulation of
new small blood vessel growth was produced at 880 nm
wavelength. Such studies have been limited by the constraints
of laser technology, but LED’s offer improved power and area of
distribution at longer wavelengths."
- Dr. Norman Salansky
880 nm
(590 - 740)
660 nm
(770 - 990)
Depth of Penetration
#3- WavelengthDetermines
Depth of
Penetration
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Wavelength & Depth of Penetration
• The longer the wavelength of the light
source, the deeper the penetration into the
tissue.
• The shorter the wavelength of the light
source, the lesser the penetration.
WAVELENGTH = Depth of Penetration
The Photobiological Basis of Low Level Laser Radiation Therapy—Kendric C. Smith, Department of Radiation Oncology,
Stanford University School of Medicine.
“Studies on the absorption spectrum of the palm of a human hand show
that radiation at 633 nm does not penetrate through tissues nearly as
well as does radiation at 830 nm".
WAVELENGTH
Near Infrared
880nm
Red
660nm
DEPTH OF PENETRATION
Red
660nm
Near Infrared
880nm
Depth of Penetration
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Tissue Penetration of Various Wavelengths
Wavelength
(nm)
Color Range Depth of
Penetration
(mm)
150-380 Ultraviolet <0.1
390-470 Violet to Deep
Blue
~0.3
475-545 Blue to Green ~0.3-0.5
545-600 Yellow to
Orange
~0.5-1.0
600-650 Red ~1.0-2.0
650-1000 Deep Red to
Infrared
2.0-3.0
1000-1350 Near to Mid-
Infrared
3.0-5.0
1350-12000 Infrared <0.1
Depth of Penetration
• Systemic effects– Direct and Indirect Effects
• Clothing will decrease penetration
• Must press the unit down if contact is necessary– Law of Cosines
• Treatment depth increases over time
• Treatment depth dependent upon wavelength– 830nm penetrates deeper than 630 nm
– Some reflection occurs in unit not in contact with skin
“Direct” vs. “Indirect” Effect of
Penetration
• “Direct” Effect:
– the biological response that occurs from absorption
of energy by the tissues
• “Indirect” Effect:
– A lessened response that occurs deeper in the
tissues.
– The normal metabolic processes in the deeper
tissues are catalyzed from the energy absorption in
the superficial structures to produce the indirect
effect.
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Wavelength and Power determine
Penetration/Absorption
Multiple Wavelengths
660nm & 880nm
Some modalities use multiple wavelengths –
allowing for multiple cellular effects.
880 nm
32 x 30 mW
660 nm
4 x 4 mW
Is it all about going deep?
• The skin is the largest and heaviest organ
in the body.
• 50% - 90% light is absorbed by the skin.
• Important systemic effects can be gained
by using lower power
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Now…
How Do We Apply
the Light??
Three Options
for
Generating Therapeutic
Light
Laser • SLD • LED
What is Laser?
• Light
• Amplification by
• Stimulated
• Emission of
• Radiation
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REVIEW…
Basic Properties of Visible Light
(400nm -700nm)
• Chromatic
– multiple colors
• Incoherent
– travels in all directions
• Uncollimated
– we can try to collimate with use of filters, etc.
Properties of Lasers
• Monochromatic –one
color
• Coherent –all the same
wavelength
• Collimated –in a beam due
to the lens
• Nothing else like it in
nature – purification of light
Ordinary Light vs.
Laser Light
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Four Components of Lasers
1. Active Medium
-may be solid crystals (ruby), liquid dyes, gases (CO2 or Helium/Neon), or semiconductors (GaAs). Active mediums contain atoms whose electrons may be excited an energy source.
2. Excitation Mechanism
-pumps energy into the active medium by one or more of three basic methods; optical, electrical or chemical.
3. High Reflectance Mirror (Feedback Mechanism)
-A mirror which reflects essentially 100% of the laser light.
4. Partially Transmissive Mirror (Output Coupler)
-A mirror which reflects less than 100% of the laser light and transmits the remainder.
Classifications of Lasers
• Revised System --part of the revised IEC 60825
standard. From 2007, the revised system is also
incorporated into the US-oriented ANSI Laser Safety
Standard (ANSI Z136.1).
• Accepted by US Food and Drug Administration (FDA)
on laser products imported into the US.
• The classification of a laser: based on accessible
emission limits (AEL) that are defined for each laser
class.
– AEL is usually a maximum power (in W) or energy (in J) that
can be emitted in a specified wavelength range and exposure
time that passes through a specified aperture stop at a
specified distance.
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Types of Lasers(Old classification – phased out after 2002)
• Class I Laser: < .5 mW power output– Not used as a therapeutic device
• Class II Laser : <1 mW power output– Minimally therapeutic
• Class IIIA Laser : < 5 mW power output– Lower end of power output, but demonstrate certain therapeutic
properties –primarily photochemical effects
• Class IIIB Laser : < 500 mW power output– Majority of therapeutic devices. Photobiomodulation. No photothermal
effects. Balance power and safety –no harm to skin or clothing,
potential damage to eyes.
• Class IV Laser : > 500 mW power output– Photothermal effects - Thermally destructive – some surgical in nature.
Revised Classes of Lasers
• Class 1
• Class 1M
• Class 2
• Class 2M
• Class 3R
• Class 3B
• Class 4
*classification system as specified by the IEC 60825-1 standard
• Class 1
– A Class 1 laser is safe under all conditions of
normal use.
• Class 1M
– A Class 1M laser is safe for all conditions of
use except when passed through magnifying
optics such as microscopes and telescopes.
Class 1M lasers produce large-diameter
beams, or beams that are divergent
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• Class 2– A Class 2 laser is considered to be safe because the blink reflex
will limit the exposure to no more than 0.25 seconds.
– Only applies to visible-light lasers (400–700 nm). Class-2 lasers
are limited to 1 mW continuous wave, or more if the emission
time is less than 0.25 seconds or if the light is not spatially
coherent. Intentional suppression of the blink reflex could lead to
eye injury. Some laser pointers and measuring instruments are
class 2.
• Class 2M– A Class 2M laser is safe because of the blink reflex if not viewed
through optical instruments. As with class 1M, this applies to
laser beams with a large diameter or large divergence, for which
the amount of light passing through the pupil cannot exceed the
limits for class 2.
• Class 3R– A Class 3R laser is considered safe if handled carefully, with
restricted beam viewing. Visible continuous lasers in Class 3R
are limited to 5 mW. For other wavelengths and for pulsed
lasers, other limits apply.
• Class 3B– A Class 3B laser is hazardous if the eye is exposed directly. The
AEL for continuous lasers in the wavelength range from 315 nm
to far infrared is 0.5 W. For pulsed lasers between 400 and
700 nm, the limit is 30 mJ. Other limits apply to other
wavelengths and to ultrashort pulsed lasers. Protective eyewear
is typically required where direct viewing of a class 3B laser
beam may occur. Class-3B lasers must be equipped with a key
switch and a safety interlock.
• Class 4– Class 4 is the highest and most dangerous class of
laser, including all lasers that exceed the Class 3B
AEL.
– By definition, a class 4 laser can burn the skin, or
cause permanent eye damage as a result of direct,
diffuse or indirect beam viewing.
– These lasers may ignite combustible materials, and
thus may represent a fire risk, even from possible
reflections of the beam (operator must take great care
to control the beam path).
– Class 4 lasers must be equipped with a key switch
and a safety interlock. Most industrial, scientific,
military, and medical lasers are in this category.
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Clinical Use of Lasers
• Low Level Laser Therapy
LLLT
“Soft” Laser
“Cold” Laser
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Types of Lasers• InGaAlP 630-685 nm
– Indium Gallium Aluminum Phosphate
• GaAs 904 nm– Gallium Arsenine
• GaAlAs 780-870 nm– Gallium Aluminum Arsenine
• Ruby 694 nm
• Nd:YAG 1064 nm
• Ho:YAG 2130 nm
• Er:YAG 2940 nm
• Alexanddrite 720-800 nm
• Dye variable nm
• Rhodamine 560-650 nm
• HeNe 633 nm -used for cauterizing in hospitals
• Argon 350-514 nm
• CO2 10600 nm
• Excimer 193-248, 308 nm
Most commonly used in practice
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Pulsing Laser Light
• May effect the body like pulsing electrical
current
• Fewer studies on the effects
• Changes the output
Pulsing Laser Light
• May be “super-pulsed” or “chopped”
• Often found in the Class IV lasers in order
to reduce thermal effects
– Twice the power not twice the depth (5-10%)
• Few studies to determine optimum
frequency of pulses
Q: Which frequency of pulses
should be used for various
conditions?
A: First -- must differentiate between “chopping” and
“super-pulsing”.
If a continuous laser is pulsed, the average output power
will be lower. With “chopped” lasers, approximately 50%
of power is lost (50% duty cycle).
• There is evidence from cell studies that the pulsing can
make a difference, but evidence from clinical studies is
almost absent.
• Must choose a frequency based upon the anecdotal
evidence for what is best for the condition(s) being
treated.
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Super-pulsed Lasers
• Greater depth of penetration may be
achieved in some cases
• Depth of penetration is dependent upon
– Wavelength
– Whether the laser is super-pulsed
– Power output
– Absorption by the tissues
Options for Application of Light
Therapy:
• Laser
– Single or multiple diodes
• SLD
• LED
LED and SLD
• LED – Light Emitting Diodes
– Usually more superficial conditions
– Initial studies show that lasers may be more
effective, but both are effective
• SLD – Super Luminous Diode
– Ability to produce several specific
wavelengths for greater spectrum of effects.
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LED and SLD
• LED (light-emitting diode) – special p-n junction
semi-conductor diode that emits visible light
when an electric current passes through it.
• A diode has a section of N-type material bonded to a
section of P-type material, with electrodes on each end.
• Electricity is conducted in only one direction.
• When no voltage is applied to the diode, electrons from the
N-type material fill holes from the P-type material along the
junction between the layers, forming a depletion zone.
When the negative end of the circuit is hooked up
to the N-type layer and the positive end is hooked
up to P-type layer, electrons and holes start
moving and the depletion zone disappears.
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The peaks of the LEDs and optimum
wavelengths are not exact, but spread out
about +/- ~10 nm so there is an overlap of
available LEDs and the biologically optimum
wavelengths.
A broader treatment area and multiple
wavelengths are possible using LED’s vs. Laser
WAVELENGTH SPECTRUM
Therapeutic Window of Light
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The BIG Controversy…
Laser
vs.
LED and SLD
LED’s vs. Lasers
• LEDs do not deliver enough power to damage
the tissue, but they do deliver enough energy to
stimulate a response from the body to heal itself.
• With a low peak power output but high duty
cycle, the LEDs provide a much gentler delivery
of the same healing wavelengths of light as does
the laser but at a substantially greater energy
output.
• For this reason, LEDs do not have the same risk
of accidental eye damage that lasers do.
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LED’s vs. Lasers
• LEDs are neither coherent nor collimated and
they generate a broader band of wavelengths
than do the single-wavelength laser.
• This allows a broader surface area of treatment.
• The multiplicity of wavelengths in the LED,
contrary to the single-wavelength laser, may
enable it to affect a broader range of tissue
types and produce a wider range of
photochemical reactions in the tissue.
“LIGHT IS LIGHT”
“If wavelength and dosage are identical,
results will be the same”
Chukuka Enwemeka, PhD, PT
“LIGHT is LIGHT”
"In these cases, the coherent and noncoherent light (i.e., both lasers
and LED’s) with the same wavelength, intensity and dose provides
the same biological response.”
"In this view, laser therapy is really a form of light therapy, and lasers are
important in that they are convenient sources of intense light at
wavelengths that stimulate specific physiological functions.”
—T.I. Karu; Cellular Mechanisms of Low-Power Laser Therapy
—Jeffrey R. Basford, M.D., Department of Physical Medicine
and Rehabilitation, Mayo Clinic, Rochester, Minnesota.
Low-Energy Laser Therapy: Controversies and New Research Findings
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"Lasers are just convenient machines that produce
radiation; It is the radiation that produces the
photobiological and/or photophysical effects and
therapeutic gains, not the machine."
—Kendric C. Smith; The Photobiological Basis of Low Level Laser Radiation Therapy.
Department of Radiation Oncology, Stanford University School of Medicine
"...according to all available data, does not depend
on the coherence of radiation."
"Photobiological Principles of Therapeutic Applications
of Laser Radiation“ published by Yu. A. Vladimirov, et al
in Biochemistry (Moscow)Volume 69, Number 1 / January, 2004
“ Wavelength determines depth-of-penetration –
the longer the wavelength the deeper the
penetration.
Qualities unique to lasers such as collimation and
coherence do not affect depth-of penetration since
both are lost once light has penetrated the first
millimeter of tissue.”
–D.C. Laycock, Ph.D., MIPEM, MBES, CGLI.,
“Lasers vs. Super Luminescent Light Emitting Diodes”
"An analysis of published clinical results from the point of view of
various types of radiation sources does not lead to the
conclusion that lasers have a higher therapeutic potential than
LEDs.
...The coherent properties of light are not manifested when the
beam interacts with a biotissue on the molecular level
....The conclusion was that under physiological conditions the
absorption of low-intensity light by biological systems is of purely
noncoherent (i.e., photobiological) nature....specially designed
experiments at the cellular level have provided evidence that
coherent and noncoherent light with the same wavelength,
intensity, and irradiation time provide the same biological
effect.
Successful use of LEDs in many areas of clinical practice also
confirms this conclusion."
Professor Tiina Karu (Biomedical Photonics Handbook, 2003).
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“By light interaction with a biotissue, coherent properties of laser
light are not manifested at the molecular level. The absorption of
low-intensity laser light by biological systems is a purely
noncoherent (i.e., photobiological) nature. On the cellular level,
the biological responses are determined by absorption of light with
photoacceptor molecules. Coherent properties of laser light are
not important when cellular monolayers, thin layers of cell
suspension as well as the layers of tissue surface are irradiated.
In these cases, the coherent and noncoherent light (i.e., both
lasers and LED’s) with the same wavelength, intensity and dose
provide the same biological response.”
Cellular Mechanisms of Low-Power Laser Therapy (Photobiomodulation)—T.I. Karu
What about the light scattering
effect of
Laser Light vs. LED Light?
Tissue scattering degrades coherent effects of lasers:
“At first glance, the polarization and coherency aspects of laser irradiation are attractive
as sources of biological effects, since (poorly defined) resonant effects might be
hypothesized to occur in the interaction of laser radiation and cellular components.
However, this view may not be tenable since 1) stimulative effects are reported following
irradiation with nonlaser light sources and 2) tissue scattering, as well as the fiber optic
delivery systems used in many experiments, rapidly degrade coherency.
Thus, any effects produced by low-energy lasers may be due to the effects of light in
general and not to the unique qualities of lasers. This view is not difficult to accept when
it is remembered that wavelength-dependent photobiochemical reactions occur
throughout nature and are involved in such things as vision, photosynthesis, tanning, and
vitamin D metabolism. In this view, laser therapy is really a form of light therapy, and
lasers are important in that they are convenient sources of intense light at wavelengths
that stimulate specific physiological functions.”
Low-Energy Laser Therapy: Controversies and New Research Findings—
Jeffrey R. Basford, M.D., Department of Physical Medicine and Rehabilitation,
Mayo Clinic, Rochester, Minnesota
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Laser Light Scatters in Tissue
LIGHT IS LIGHTSLD vs. Laser
“Lasers, however, have some inherent characteristics which make their use in a
clinical setting problematic, including limitations in wavelength capabilities and
beam width… Light-emitting diodes (LEDs) offer an effective alternative to
lasers.
Due to the nature of light physics and engineering constraints of laser design, the
range of wavelengths attainable is limited. Due to the coherent beam of light
unique to lasers, their ability to easily treat large areas is also limited.
Development of light emitting diodes (LED) offers an alternative source for light
therapy that can be designed to produce many wavelengths and in an array to
emit light at wavelengths proven, in prior studies of laser light, to speed wound
healing.”
Medical Applications of Space Light-Emitting Diode Technology—Space Station and Beyond—
Harry T. Whelan, M.D., John M. Houle, B.S., Deborah L. Donohoe, A.S., L.A.T.G., Dawn M. Bajic,
B.S., Meic H. Schmidt, M.D., Kenneth W. Reichert, M.D., George T. Weyenberg, R.N.,
David L. Larson, M.D., Glenn A. Meyer, M.D., James A. Caviness, M.D.
By the time laser-generated light has passed through
the first millimeter of tissue, the unique qualities of
collimation and coherence are primarily lost.
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APPLICATIONS
CONTRAINDICATIONS / WARNINGS for
Light TherapyDo not use Light Therapy:
• Over and around the uterus during pregnancy.
• Where there is active ongoing hemorrhaging / bleeding tendencies.
• When there is any indication or diagnosis of blood clots.
• Over and around the thyroid gland.
• Cancer (tumors or cancerous areas).
• Over open wounds unless covered with a clear sterile protective
barrier. (An open wound may be treated in the non-contact mode without
protective barrier since the probe is never placed on the wound in the non-
contact mode).
• Over the cardiac region and Vagus nerve.
• Where analgesia/ pain relief may mask progressive pathology.
• Over an area that has been treated with a photosensitizing agent.
• In a patient taking medication that may cause sun-sensitivity (some
antibiotics and St. John’s Wort)
• In a patient with Epilepsy (pulsed light therapy)
• Over the growth plates in children
• Direct irradiation of eyes.
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Indications for Light Therapy• Tension Headache
• Migraine Headache
• TMJ
• Neck-Shoulder Pain
• Frozen Shoulder
• Tennis Elbow or Golfer’s Elbow (Lateral and Medial Epicondylitis)
• Osteoarthritis over the thumb (1st MCP joint)
• Low Back Strain
• Sciatica
• Hip or Knee Arthritis or Injury
• Tendinitis – Achilles
• Ankle Sprain
• Plantar Fascitis
• Wound Repair
• Burns
• Carpal Tunnel Syndrome
• Sinusitis
• Sports Injuries
• Trigger Points
• Shingles
* Be sure to stay within your scope of
practice!
WI Chiropractic
Scope of Practice
• The practice of chiropractic is the application of
chiropractic science in the adjustment of the
spinal column, skeletal articulations and
adjacent tissue which includes diagnosis and
analysis to determine the existence of spinal
subluxations and associated nerve energy
expression and the use of procedures and
instruments preparatory and complementary to
treatment of the spinal column, skeletal
articulations and adjacent tissue.
Clinical Studies of LLLT:
• >130 double-blind positive studies confirming
the clinical effect of LLLT.
• More than 3000 research reports are published
with more than 90% of these studies verifying
the clinical value of laser therapy.
• About 250 papers are annually published in
peer reviewed scientific papers.
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Various resources to find
research…
• www.pubmed.com
• www.medscape.com
• www.laser.nu (Swedish Laser Medical Society)
• http://www.healinglightseminars.com/librar
y.html
• http://www.walt.nu (World Association for Laser Therapy)
• www.naalt.org (North American Association for Laser Therapy)
Low Level Laser Therapy (LLLT)
Applications, Case Studies and Low
Level Laser Research
• MUSCULOSKELETAL PAIN
SYNDROMES (CHRONIC AND ACUTE):
– LLLT has been shown to be effective in a
variety of musculoskeletal conditions and
associated pain presentations.
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Acute low back pain with radiculopathy:
a double-blind, randomized, placebo-
controlled study
• Konstantinovic LM, et al: Photomed Laser Surg.
2010 Aug;28(4):553-60
• RCT, double-blind, placebo-controlled trial was
performed on 546 patients.
– Group A (182 patients) was treated with nimesulide
200 mg/day and additionally with active LLLT
– Group B (182 patients) was treated only with
nimesulide
– Group C (182 patients) was treated with nimesulide
and placebo LLLT.
– LLLT was applied behind the involved spine
segment using a stationary skin-contact
method. • Pts treated 5x/wk, for a total of 15 treatments, with the
following parameters: wavelength 904 nm; frequency 5000
Hz; 100-mW average diode power; power density of 20
mW/cm(2) and dose of 3 J/cm(2); treatment time 150 sec at
whole doses of 12 J/cm(2).
• The outcomes were pain intensity measured with a visual
analog scale (VAS); lumbar movement, with a modified
Schober test; pain disability, with Oswestry disability score;
and quality of life, with a 12-item short-form health survey
questionnaire (SF-12).
• Subjects were evaluated before and after treatment.
Statistical analyses were done with SPSS 11.5.
LLLT and acute LBP with
Radiculopathy – 2010 study
• CONCLUSIONS: The results of this study
show better improvement in acute LBP
treated with LLLT used as additional
therapy (Group A).
Konstantinovic LM, et al
Photomed Laser Surg. 2010 Aug;28(4):553-60
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LLLT for acute neck pain with
radiculopathy:
• Pain Med. 2010 Aug;11(8):1169-78
• The objective of the study was to investigate
clinical effects of low-level laser therapy in
patients with acute neck pain with radiculopathy.
This was a double-blind, randomized,
placebo-controlled study.
• The study was carried out between January
2005 and September 2007 at the Clinic for
Rehabilitation at the Medical School, University
of Belgrade, Serbia.
60 pts received a course of 15 treatments over 3
weeks with active or an inactivated laser as a
placebo procedure.
LLLT was applied to the skin projection at the
anatomical site of the spinal segment involved
with the following parameters:
• wavelength 905 nm
• frequency 5,000 Hz
• power density of 12 mW/cm(2)
• dose of 2 J/cm(2)
• tx time 120 sec at whole doses 12 J/cm(2).
• The primary outcome measure was pain intensity as
measured by a visual analog scale.
• Secondary outcome measures were neck movement,
neck disability index, and quality of life.
• Measurements were taken before treatment and at the
end of the 3-week treatment period.
• Statistically significant differences between groups were
found for intensity of arm pain and for neck extension.
• LLLT gave more effective short-term relief of arm
pain and increased range of neck extension in
patients with acute neck pain with radiculopathy in
comparison to the placebo procedure.• Pain Med. 2010 Aug;11(8):1169-78
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Effect of low-level laser (Ga-Al-As 655 nm)
on skeletal muscle fatigue induced by
electrical stimulation in rats
“We conclude that LLLT doses of 0.5 and 1.0
J/cm2 can prevent development of muscular
fatigue in rats during repeated tetanic
contractions.”
Rodrigo Álvaro B. Lopes-Martins,1 Rodrigo Labat Marcos,1 Patrícia Sardinha Leonardo,1 Antônio Carlos Prianti, Jr.,1 Marcelo Nicolas Muscará,1 Flavio Aimbire,2 Lúcio Frigo,3 Vegard V. Iversen,4 and Jan Magnus
Bjordal5
J Appl Physiol 101: 283-288, 2006. First published April 20, 2006; doi:10.1152/japplphysiol.01318.2005
8750-7587/06
The effect of 300mW, 830NM laser on
chronic neck pain: a double- blind,
randomized, placebo-controlled study
-Chow RT et al. Pain. 2006 Jun 23
• 90 patients with chronic neck pain for at least 3
months up to 15 years (mean duration 11 years)
were given 14 treatments with laser over 7
weeks.
• At 1 month after treatment, 82% of patients in
the active group achieved a positive response
vs. only 29% in the placebo group.
Low level laser therapy before eccentric
exercise reduces muscle damage
markers in humansBaroni BM, Leal Junior EC, De Marchi T, Lopes AL, Salvador M, Vaz MA.
Eur J Appl Physiol. 2010 Jul 3. [Epub ahead of print]
• After LLLT or placebo treatment, subjects performed 75
maximal knee extensors eccentric contractions (five sets
of 15 reps.
• Muscle soreness (visual analogue scale-VAS), lactate
dehydrogenase (LDH) and creatine kinase (CK) levels
were measured prior to exercise, and 24 and 48 h after
exercise.
• LLLT treatment before eccentric exercise was effective in
terms of attenuating the increase of muscle proteins in the
blood serum and the decrease in muscle force.
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Effects of Low-Level Laser Therapy (LLLT) in
the Development of Exercise-Induced Skeletal
Muscle Fatigue and Changes in Biochemical
Markers Related to Post-Exercise Recovery
• J Orthop Sports Phys Ther. 2010 Apr 12. [Epub ahead of
print] Leal Junior EC, Lopes-Martins RA, Frigo L, De Marchi T, Rossi RP, de
Godoi V, Tomazoni SS, da Silva DP, Basso M, Filho PL, de Valls Corsetti F, Iversen
VV, Bjordal JM.
• CONCLUSION: We conclude that pre-exercise
irradiation of the biceps with an LLLT dose of 6 J per
application location, applied in 2 locations, increased
endurance for repeated elbow flexion against resistance,
and decreased post-exercise levels of blood lactate, CK,
and CRP.
Effects of superpulsed low-level laser
therapy on temporomandibular joint pain.
• Marini I, Gatto MR, Bonetti GA., Clin J Pain. 2010 Sep;26(7):611-6.
• OBJECTIVES: A randomized double-blind study was
conducted to compare the efficacy of superpulsed low-
level laser therapy (SLLLT) with nonsteroidal anti-
inflammatory drugs in the treatment of pain caused by
temporomandibular joint disorders.
DISCUSSION: Mandibular function improved in all
SLLLT patients proving the effectiveness in the
treatment of pain, as demonstrated by a significant
improvement in clinical signs and symptoms of
temporomandibular joint disc displacement without
reduction and osteoarthritis at the end of treatment and
stability over a period of 1 month.
Clinical Evidence and Guidelines for Laser
Phototherapy
in Tendinopathies and Arthritis
NAALT Conference 2011Jan M. Bjordal
Professor ,PT, PhD,
Bergen University College & University of Bergen, Norway
Leeds Metropolitan University, Great Britain
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Pessoa et al. 2005 Photomed Laser Surg
14 days after injury
LLLT Steroids
Optimal LLLT enhances tissue repair,
while steroids inhibit tissue repair
LLLT vs. Steroids
Conclusions1. Most musculoskeletal pain treatment guidelines are confounded
by authors´ conflict of interests with the drug industry
2. Pain treatment guidelines should be developed by authors
without conflicts of interest with any manufacturer of drugs or
pain relief devices
3. Optimal LLLT has greater short-term efficacy than NSAID and
greater long-term efficacy than steroid injections in
tendinopathies
4. In neck pain, there is no evidence in support of NSAID use,
while LLLT efficacy is supported by firm scientific evidence
5. LLLT is at least equally effective as NSAID in low back pain and
osteoarthritis
6. LLLT has superior safety over NSAID and steroid injections in
musculoskeletal pain
Pessoa et al. 2005 Photomed Laser Surg
Use common and
clinical sense
when reviewing
research!
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FDA Approved Uses• Chiropractors and CTs who have taken an
approved continuing education class are allowed to use cold laser and light therapy to treat patients for conditions within their scope of practice “but only if those uses have been approved by the federal Food and Drug Administration.” (FDA)
• The FDA approves a cold laser or light therapy device with what is known as a 510(k) form.
• It is important that the device you are utilizing within your office have a 510(k) approval and that you know what indications have been approved.
Examples of FDA Approved
Uses• Example – one specific modality received
approval in 2002 “to provide topical heating for
the temporary increase in local blood circulation,
temporary relief of minor muscle and joint aches,
pain and stiffness and relaxation of muscles; for
muscle spasms, and minor pain and stiffness
associated with arthritis.” It is also approved for
the temporary relief of hand and wrist pain
associated with carpal tunnel syndrome.
Examples of 510(k) Approvals:
• “for the temporary increase in local blood circulation; temporary relief of minor muscle and joint aches, pains and stiffness; for relaxation of muscles; for muscle spasms; and minor pain and stiffness associated with arthritis.”
– Approval # K031329
– http://www.fda.gov/cdrh/pdf3/K031329.pdf
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• approval in 2003 for the indication of
“adjunctive use in the temporary relief of
hand and wrist pain associated with
Carpal Tunnel Syndrome.”
Examples of 510(k) Approvals:
• approval in 2002 for the indication of
“adjunctive use in the temporary relief of
hand and wrist pain associated with
Carpal Tunnel Syndrome.”
Examples of 510(k) Approvals:
Examples of 510(k)
Approvals
• approval in 2004 for the indication of
“adjunctive use in providing temporary
relief of pain associated with iliotibial band
syndrome.”
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Examples of 510(k)
Approvals
• approval for the indication of “elevating
tissue temperature for the temporary relief
of minor muscle and joint pain and
stiffness, minor arthritis pain, or muscle
spasm; the temporary increase in local
blood circulation; and/or the temporary
relaxation of the muscle.”
Examples of 510(k)
Approvals
• approval in 2003 for the indication of
“adjunctive use in temporary relief of hand
and wrist pain associated with Carpal
Tunnel Syndrome.”
Examples of 510(k)
Approvals
• ….intended to emit energy in the infrared
spectrum to provide topical heating for the
purpose of elevating tissue temperature for the
temporary relief of minor joint pain and stiffness,
minor arthritis pain, or muscle spasm, the
temporary increase in local blood circulation
and/or promoting relaxation of muscles.» FDA approval K043586
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510(k) Approval
• Before buying a laser or light therapy device, ask
the vendor for a copy of the FDA 510(k)
approval to be sure that the device has been
approved for the indications which you (the
doctor) intend to treat within the office.
• Always treat within your scope of practice –
regardless of what the modality is approved for.
Application Considerations…
“Dosage”
• Dosage is often measured in Joules per
unit or in Joules
• Time is dependent upon the power of the
modality being used.
• Too much, too little, poor contact, lack of
absorption…. All reasons for poor
outcomes
Irradiance vs. Time as
“dosage”…
• Irradiance (W/cm2)
Often called Intensity, or Power Density and
is calculated as
Irradiance = Power (W)/Area (cm2)
More accurate representation of dosage than
just “time”
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Pulse Structure• Peak Power (W)
• Pulse freq (Hz)
• Pulse Width (s)
• Duty cycle (%)
If the beam is pulsed, then the Power should
be the Average Power and calculated as
follows:
Average Power (W) = Peak Power (W) ×
pulse width (s) × pulse
frequency (Hz)
Arndt-Schultz
Principle
• There is an optimal amount of energy
absorption per unit of time that is
beneficial.
• Too much, or too little, loses therapeutic
benefits.
• Too little stimuli will not produce effects,
whereas too much stimuli may actually
have harmful effects.
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Q: What happens if too
high of a dose is applied?
• A: May have a non-optimal
effect, or worse, a
biosuppressive effect .
• For example: The healing of a
wound may take longer time than
normally expected.
• Very high doses on healthy tissues
will not damage them.
Cosine Law
Radiant energy is more easily transmitted to
deeper tissues if the source of radiation is at
a right angle to the area being radiated.
Law of Cosines
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Conventional Treatment Protocols
• Treatment parameters are designed to get the required amount of photons to the target tissue
• Given the same amount of J/cm2, a higher dose over a shorter period of time is preferred.
• Typically treatment will be directed at the injured area. Apply Laser or Light:
– Over the damaged tissue
– Over the affected nerve roots
– Over the muscle insertion
– Over trigger points or tender points
– Over acupuncture points related to the condition
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Conventional Treatment
Protocols
• When treating points, push down with the laser
or probe to move the blood out of the way to get
better/deeper penetration. (Be careful if using a
high-powered laser that may cause heat!!)
• When treating edema – treat the proximal part
first in order to promote drainage before treating
the distal part.
Conventional Treatment
Protocols
• In order to get the desired amount of therapy
into a target tissue, the probe or cluster needs to
be stationary.
• If the probe/therapy head is moving, then the
treatment time needs to be changed
accordingly.
• In other words, treat multiple points instead of
moving the probe.
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• Treat proximal areas
before distal regions
Conventional Treatment Protocols
• Frequency of Treatment: Light therapy
has been shown to have a cumulative
effect – every other day to 3x/wk for the
first 2 wks is recommended.
• Chronic conditions may be aggravated in
the first few treatments
• Acute conditions usually respond quicker
than chronic.
Dosage Recommendations
• Refer to user’s manual if backed by research
• Per World Association for Laser Therapy:
– For LLLT of 904nm
http://www.walt.nu/images/stories/files/Dose_table_90
4nm_for_Low_Level_Laser_Therapy_WALT-2010.pdf
– For LLLT of 780-860 nm:
http://www.walt.nu/images/stories/files/Dose_table_78
0-860nm_for_Low_Level_Laser_Therapy_WALT-
2010.pdf
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Reminder!
• The State of Wisconsin restricts the use of
a Light Therapy device to the purpose
specified on the FDA 510(k) statement.
• You should have a written copy of the
510(k) statement from the manufacturer.
• The state will not accept “ignorance” as an
excuse.
Applications
• Refer to your User Manual
• Be sure to check the 510(k) FDA approval
• Class Examples:
Specific Examples:
• Neck / Shoulder Pain
• Lateral Epicondylitis
• Soft Tissue Inflammation
• Cervical Radiculopathy
• Other conditions: TMJ, sinus pressure, migraine/headaches, plantar fasciitis, tight muscles, etc.
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Specific Examples:
• Lateral Epicondylitis (Tennis Elbow)
– Using Light Cluster Probe or Laser
– Treatment Areas:• Insertion site – extensor muscles at the lateral
epicondyle
– Dosage:• 1-3 J/cm2 per point
• 1-2x/wk for 3-6 wks.
• Consider treatment of cervical region if slow progress
Specific Examples:
• Soft Tissue Inflammation (including bursitis,
tendonitis, etc.)
– Treatment areas:
• Points along inflammed areas – treat proximal
before distal
– Dosage:
• 4-8 J/cm2 per point – select dosage based upon
depth of the target tissue (deeper needs higher
dosage)
• 2-3x/wk
• Review of modalities used for
demonstration in this class:
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Neck / Shoulder Pain
Neck / Shoulder Pain– Direct skin contact
– Treatment Areas:• Paravertebrally from C5-T2
– Dosage:• 3-4 J/cm2 per point
• 1-2x/wk for 3-4 wks
– Also consider treatment over trigger points especially in the trapezius muscle, rhomboids & levatorscapulae
– Chiropractic adjustments as clinically indicated.
Lateral Epicondylitis
Lateral Epicondylitis (Tennis Elbow)– Using Light Cluster Probe
– Treatment Areas:• Insertion site – extensor muscles at the lateral epicondyle and
then distal through the extensor muscle
• Cervical and cervicothoracic muscles, trigger points, etc.
– Dosage:• 2-4 J/cm2 per point
• 1-2x/wk for 3-6 wks.
• Consider further treatment of cervical region if slow progress
– Include chiropractic adjustment to subluxations at elbow, wrist and cervicothoracic regions as clinically indicated, ice massage & extensor stretches/exercises.
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Soft Tissue Inflammation
Soft Tissue Inflammation
(including bursitis, tendonitis, etc.)
– Treatment areas:
• Points along inflamed areas – treat proximal before distal
• Include trigger points if indicated
– Dosage:
• 4-8 J/cm2 per point – select dosage based upon depth of the
target tissue (deeper needs higher dosage)
• 2-3x/wk
– Chiropractic adjustments as clinically indicated.
Cervical Radiculitis
Cervicobrachial Radicular Pain– Direct skin contact
– Treatment Areas:• Disc level (4J)
• Paravertebrally from C5-T4-5 bilaterally if indicated
• At trigger points, tight points– include scalenes, traps, rhomboids, levator scap
• Along dermatome
– Dosage:• 3-4 J/cm2 per point
• 3x/wk for 3-4 wks
– Chiropractic adjustments & treatment as clinically indicated.
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“The sun with all those planets revolving around it and dependent on it, can still ripen a bunch of grapes as if it had nothing else in
the universe to do.”
Galileo Galilei (1564-1652)
Cold Laser
and Light Therapy
By:
Dr. Wendy L.C. Varish, DC, FACO, CCSP, CCOHC