Light Therapy Flashcards
Therapeutic window of light
660 nm to 880 nm
Bacetericidial blue light therapeutic wavelengths
400 nm
Not used therapeutically
Collagen rebuilding - therapeutic wavelength -
580-590 nm
Tissue repair/pain control - therapeutic wavelenth
600-1000nm
660-880 nm is more specific though for dynatronics
The longer the wavelength of the light source - (penetration)
The deeper the penetration into the tissue
Shorter wavelength = lesser the penetration
Infrared penetrates more
visible red (2-4cm)
LASER
light amplification of stimulated emissions of radiation
Laser is form of
electromagnetic energy
Three unique properties for a laser
Coherence
Monochomaticity
Collimation
Coherent light
One wavelength and beam is very focused
Noncoherent light
Losing some of light energy because of non coherance
Laser vs. LED wavelength
Laser = one very specific wavelength
LED light = one peak wavelength but others surrounding the peak as well
Differences with laser and light
Laser = monochromatic (same wavelength Light = can be multiple wavelengths Laser = no divergence of photons Light = diverges Laser = coherent Light = noncoherent
Laser types
High power
Low power –> helium neon and gallium arsenide
Helium neon laser
Red beam
Continuous wave
1-2 mm direct penetration
10-15 mm indirect
Gallium Arsenide laser
Invisible
Pulse mode
1-2cm direct penetration
5 cm indirect
Lasing technique options
Direct contact (on skin) Scanning (10-15 cm or so above skin)
Dosage reported as
J/cm2 (energy density)
Joule = 1 W/s
Dosage is dependent on the
laser output in mW, the time of the exposer in seconds, and the beam surface area of the laser in cm2
Energy is measured in
Joules or millijoules (mJ)
Energy is a function of
power and time and a better determinant of the effects of light on tissue
Energy =
power x time
Energy density is measured in
HJoules/squared cm
Preferred unit for reporting doses of treatment
Energy density
Dosimetry
Therapeutic treatment depends on condition, in PT usually 1-8 J/cm2
Important parameters for dosimetry
Power/power density Energy density Wavelength Duration of treatment Size of the area being treated
Power is measured in
watts or milliwatts
Power determines what
length of treatment
Power and treatment time relationship
inverse
Indications
Pain reduction Facilitate wound healing Inc scar tensile strength Dec inflammation Bone healing
Contraindications
4-6 months post radiation therapy Pregnant Malignancy Over eyes Over endocrine glands Over active bleeding Over epiphyseal plates, gonads, sympathetic ganglia, vagus nerve, chest
Safety
Low level light not does injury eyes
Protective glasses for laser treatments
Do not look directly into light source
Acute conditions
Laser density 0.05 to 0.5 J/cm2
Subacute or chronic conditions
Laser density 0.5 to 3 J/cm2
How many treatments for the effecct
3-6
Pain management - trigger point
Probe held perpendicular to target with light contact on skin
Treat distal to proximal
Place joint in open position
For superficial use what laser type
HeNe
For deep use what laser type
GaAs
Wound care - effects in vitro
FIbroblast proliferation
Microphage stimulation
Collagen synthesis
Bactericidal
Light technique - wound
Gridding (contact) Tip perpendicular to skin
Scanning (no contact)Tip is perpendicular and 5-10 mm from skin
Beam should fill area of 1 cm2
Treatment recommendations EBP
3x per week
Gridding technique
Continue until re-epithelialization
Minimal research
Scar tissue remodeling
Hypertrophic scars
Scar pain/edema
Treat peripheray of scar due to dec vascular structure
Edema and inflammation
Interrupts/inhibits foramtion of kinins, histamines, and prostaglandins
Optimize cell membrane permeability
Power density in treatment determines
How long a treatment should be and how destructive treatment can be
Energy density =
power density x time
