Fringe Flashcards
(28 cards)
Therapeutic LASER
- Light Amplification by Stimulated Emission of Radiation
~ Cold laser because of the low power
used (<500 mW)
~ Emits photons into the tissues
> Individual parts of a light wave
> Zero mass
> No electric charge
Characteristics of LASER Light: Coherence
Photons emitted from a specific medium have some spacing relationships within the light wave
Characteristics of LASER Light: Monochromatic
- Emitted light waves from a specific medium have a single defined wavelength
~ Emits light that’s only one color
> Ambient light is composed of
many wavelengths and colors
Characteristics of LASER Light: Collimated
The light from a laser emerges in an extremely thin beam with very little divergence
Class 3 LASER
- Due to low power, class 3 lasers don’t heat up tissues
~ Low Level Laser
~ Cold laser
~ Soft laser
> Pts. may perceive an increase in
temperature due to potential
increased circulation
Effects of LASER Tx: Photomodulation
- Light modifies biological processes by interacting with cellular photoreceptors
~ Effects determined by the amount of
energy/photons absorbed
> More photons = more effects
Effects of LASER Tx: Wound/Tissue Healing
- Most evidence comes from wound healing studies.
~ Increases number and/or activity of
fibroblasts.
~ Speeds conversion of fibroblasts to
myofibroblasts.
> Myofibroblasts help contract
wound margins.
Effects of LASER Tx: Pain
- Evidence that laser decreases pain, but no clear mechanism identified
~ Healing
~ Inhibition of nociceptor.
Class 4 LASER
- Uses increased power (>500 mW)
- Heats superficial tissues
~ All effects of heat are in play
~ Uncertainty exists relative to
photomodulation effects - Can burn pt.
Arndt-Schultz Law
- There’s an amount of energy that’s optimal
- Less than that will cause no effects and greater levels will be detrimental to tissues
- At a certain point Tx is no longer beneficial
Dosage of Laser Tx
- Theoretically dosage should match the condition
~ Need enough photons in the area to
make a change - Power output of the units is often fixed so the way to alter dosage is by manipulating the Tx time
LASER Indications
- Any condition that requires healing
- Pain
LASER Contraindications
- Cancer
- Directly over eyes
Bottom Line of LASER?
- If light doesn’t penetrate the desired tissues, there will be no beneficial effects
- Depth of penetration is a function of wavelength color
~ 600-1000 nm typically used
Monochromatic Infrared Energy (MIRE)
- Application of near infrared light energy to the tissues.
~ Infrared
> Light energy that can not be seen.
> Produces heat energy.
> Ex. Heat from a fire or light bulb.
~ Near Infrared
> Light energy that can be seen.
> Does produce heat, but very little.
Effects of MIRE
- Appears to increase fibroblast activity
- Appears to increase nitric oxide levels in the tissues treated
Effects of MIRE: Nitric Oxide Function
- Acts as a vasodilator = increased circulation
~ Nitric Oxide is produced by many
tissues including blood vessels
> Production of nitric oxide causes
smooth muscle to relax
MIRE Indications
- Sub Acute/Chronic conditions
- Any condition where increased circulation is needed
~ Wounds
~ Fracture
~ Diabetes - Pain
- Spasm
MIRE Contraindications
Acute conditions
Longwave US
- Application of long wave length ultrasound = low frequency ultrasound.
- Typical US Frequencies
~ 1 MHz = 1000 kHz
~ 3 MHz = 3000 kHz - Longwave Ultrasound Frequency
~ Very low
> .045 MHz = 45 kHz
• much deeper & much
more divergence
Longwave US Characteristics: Frequency and Intensity
- Frequency
~ As frequency increases:
> Depth Decreases - due to
greater absorption of
superficial tissues.
> Divergence Decreases - Intensity
~ Very low
> Measured in milliwatts mW.
> Ex: 60 mW/cm2 = 06 W/cm2 - Does not heat up tissues
Longwave US Effects
- Increases Cell Membrane Permeability
- Stimulates Fibroblast Activity
- Stimulates WBC Activity
- Stimulates Osteoblast Activity
Microcurrent Electrical Stimulation
- Current applied at an intensity below sensory or motor levels (pt. doesn’t feel anything)
~ Current parameters are extremely
variable between manuracturers.
~ 1/1000 the amperage of TENS, but
much longer pulse duration.
~ Effects are not well understood.
> Some studies do show
improvement, but not greater
than other available modalities.
• Improvement shown in
studies using electrodes
implanted in the tissues.
• Improvement shown with
DC variety with negative pole.
Microcurrent Electrical Stimulation: Theory/Effect of Injury
- Tissue trauma increases the cells resistance to electrical current.
- The body’s intrinsic bioelectrical currents take the path of least resistance around the site of trauma.
~ Results in diminished bioelectrical
activity within the site disrupting cell
homeostasis