the use of ir lasers in wound healing
TRANSCRIPT
The Use of IR Lasers In Wound Healing
Jim Ohneck, FASLMS
Overview
Brief Review of Laser Technology
Laser Therapy Biology
Scientific Work
Clinical Work
LASER
An acronym for:
Light
Amplification by
Stimulated
Emission of
Radiation
Properties of Laser Light
Laser Classifications
Class IIIa = lasers 1 to 5mw of power (laser pointers)
Class IIIb = lasers 6 to 500mw in power (typical cold laser you read about)
Class IV = lasers above 500mw of power
Surgical versus Therapeutic Lasers
Surgical Laser Beam- Infrared energy collimated to a fine beam causes tissue destruction
Therapeutic Laser Beam- dispersal of same energy causes tissue stimulation
Laser Energy has the capability to penetrate into tissue to varying depths depending on its
corresponding wavelength, power and energy
concentration
Lasers in Medicine
Surgical Lasers: are used to cut, coagulate and evaporate tissues. This type of laser replaces the scalpel of the surgeon.
Lasers in Medicine
Therapeutic Lasers: are used for the stimulation of cell function.
The biological effect is photochemical not thermal, as is the case with surgical lasers.
How Light Penetrates Tissue
As light energy hits the surface of the skin and subsequent deeper layers, some of it is scattered and some of it is absorbed
At each tissue interface less energy is available to pass further through to the next layer because of the effects of absorption, reflectance and transmission
Laser Tissue Interactions
Laser Tissue Interaction
The longer the wavelength the deeper
the penetration in the IR-A spectrum
Absorption Curves
Low melanin, low water, low hemoglobin
Depth Penetration Factors
Patient
Skin pigmentation, hair
Thickness of each tissue layer
Vascular content of treatment area
Cleanliness of treatment area
Heat results in increased vasodialation
Heat caused by improper choice of wavelength
Hot spots within the fiber
Heat is a natural by product of absorption
Depth Penetration Factors
Instrumentation
Total power
Spot size
Dosage
Power density
Wavelength
Method of delivery
Clinical Variables
ClinicalFrequency of treatmentsDuration of treatmentsTotal number of treatmentsTime between treatmentsMethod of applicationCondition being treatedArea of the woundWound dressings/topical agents
Importance of Power Density
Approximately 65% of the energy delivered is lost in the epidermis
If you don’t start with enough energy there will not be enough to stimulate cell healing
If you do not have sustained power density over a long enough period of time treatments may be ineffective
Too much power density can also be detrimental
Laser Therapy Paradigm
Think of therapeutic lasers as you would a biochemical paradigm, the difference being that light initiates the chain reaction of events
Cellular Effects of Laser Energy
Chromophores are components of molecules which absorb light.
The stimulation of chromophores on mitochondrial membranes incites the production of cellular energy (ATP).
Cellular Effects of Laser Energy
Increased Growth factor response within cells and tissue as a result of increased ATP and protein synthesis
Accelerated cell reproduction and growth leading to faster repair of damaged tissues.
Increased metabolic activity- via increase in enzyme outputs, oxygen and nutrient availability.
Why IR Laser for Wounds
Depth penetration and absorption characteristics
Technology well developed and used in other medical disciplines, such as pain management
Promising scientific evidence
EFFECTS OF INFRARED LASER EXPOSURE IN A CELLULAR MODEL OF WOUND
HEALING
Mark Skopin, James Ohneck and Scott Molitor
Recent Research
Local Work Using IR Laser
EFFECTS OF INFRARED LASER EXPOSURE IN A CELLULAR MODEL OF WOUND HEALING
Moderate doses of IR light improves wound healing in vitro
Beneficial effects reduced or negated by excessive exposure
Demonstrates need for supervised treatment
Requires use of well-developed protocol
Exposure doses require knowledge of wound depth, skin pigmentation and absorption characteristics at each tissue layer
In vitro method useful for testing novel light sources or treatment paradigms
Automated image processing routines allow for accurate quantification of results
Power density was the most important identified parameter
Scott Molitor, Mark Skopin, James Ohneck
Scientific & Clinical Validation
New York Institute appearing in Photomedicine and Laser Surgery, Volume 22, Number 3 2004 authored by Chukuka S. Enwemeka, Ph.D., FACSM
“The Efficacy of Laser Therapy in Wound Repair: AMeta-Analysis of the Literature”
Scientific & Clinical Validation
New York Institute ArticleMeta analysisEvaluated stringent inclusion criteria
Type of LASER and precise wavelengthLaser clearly identified as independent variableAt least one index of wound healing identified as dependent variableParameters on laser power and time were clearly statedCondition treated clearly stated
Scientific & Clinical Validation
New York Institute Article
Conclusion was that laser therapy was effective for treating wounds
That outcomes vary with treatment parameters
Energy density was the only parameter with predictable dose dependent effects
Local Work Using IR LaserPain And Wound Healing After Acute Traumatic Injury
Slight decrease in pain as measured by FACES pain scale at 6 weeks in LASER group compared with control group
Slight improvement on wound healing rate as measured on serial pictures
Acute traumatic injury
( 1 week postop)
Acute traumatic injury
( 4 weeks postop)
After 7 Laser treatments
Acute traumatic injury
( 12 weeks postop)
Conclusions
Considerable Data is available to support the use of lasers therapeutically for wound healing
Basic scientific work has begun, some locally
IR Lasers offer demonstrated wound healing opportunities along with the advantage of stable core technology, increased depth penetration and larger treatment beam diameters