Laser Biophysics Flashcards
L.A.S.E.R
Light
Amplification
By Stimulated
Emission
Of Radiation
Light
Recognized by its wavelength and wavelength is measured in nanometers
Ionizing radiation.
Gamma Rays, X-Rays, Ultraviolet light
1-399 nm
Cancer causing
Aesthetic laser wavelength
400-780nm visible light
Fitz 1-3
Laser Medium
Stagnant lighy passes through the medium gives you the wavelength which allows you to go deep, shallow, in between. True lasers have mediums
4 types of mediums
Solid
Liquid
Gas
Semiconductor
Solid
Ruby 694 nm
Alexandrite 755 nm
Nd:YAG 1064 nm
Erbium YAG 2940 nm
Liquid
Pulsed Dye Laser
Rhodamine 585 nm (PDL)
Gas
Argon 510 nm
Carbon Dioxide 10,600 nm
Semiconductor
Diode 810 nm
Not solid
Two types of delivery systems
Fiber optic
Articulating arm
True light qualities
Coherent
Monochromatic
Collimated
Intense Pulsed Light
Non collimated
Polychromatic
Non coherent
Wavelength
Nanometers (NM)=depth in skin
Fluence
Joules (J)=power/energy/“heat” - turn it up
Absorption coefficient (AC)
Targeted chromophore(TC)= selective photothermalysis = target-light, heat, destroy
Pulse Duration
Pulse width=time in the tissue/distance between peaks (crests) of heat (epidermal cooling=millisecond (ms), nanoseconds (ns), or picoseconds (ps)
What makes laser light unique?
Collimated
Coherent
Monochromatic
More damaging to eyes
Pulsed Light Systems
Polychromatic
Divergent, Non-Coherent
Less Damaging to the eye
For laser energy to produce any biological effect in skin, it must be absorbed
TRUE
When matter is exposed to light the following actions must take place
Scattering- deviations fro straight path by inconsistency in medium
Transmission-
Absorption-
Reflection
Chromo=COLOR PHORE=carrier
4 main components of skin that selectively absorb laser light
- Melanin (pigment) - hair, age spots, freckles
- Hemoglobin (blood) - spider veins, rosacea, vascular birthmarks
- Water (wrinkles)- Intra and Extra cellular water
- Tattoo ink
Targeted Chromophore
Intended target of the laser treatment
Melanin for laser hair reduction
Competing Chromophore
A Chromophore in the treatment area that is a competing target for the laser. Melanin in the skin is a competing chromophore when performing LHR
Chromophore Sheilding
Intended targeted chromophore is shielded by another chromophore. Tattoo pigment
Selective Photothermolysis
PHOTO= LIGHT THERMO= HEAT LYSIS=DESTRUCTION
Process of selectively delivering thermal injury to a specific target based on its absorption characteristics while allowing the surrounding tissue to remain un damaged
