Low level laser therapy

Question 1

What does LASER stand for?

Answer 1

light amplification by stimulated emmision of radiation

Question 2

what theory is laser based on?

Answer 2

theory of albert einstein

Question 3

what are the higher frequencies of light?

Answer 3

x rays, gamma rays, ultraviolet cause ionization

Question 4

visible light

Answer 4

violet
infared
ultraviolet

Question 5

light is transmitted as waves and is packaged in what?

Answer 5

photons

Question 6

what are the principles of laser generation

Answer 6

adding energy to electrons causes them to move to higher orbit
if the electron gives up energy it moves to a lower orbit
spontaneous emission

Question 7

what is spontaneous emission?

Answer 7

giving up energy

Question 8

describe stimulated emissions

Answer 8

an excited atom will release a photon
if that photon interacts with another excited atom, it will release another photon
both photons have identical frequency, direction and phase
both photons continue to cause the release of other identical photons as long as excited atoms are present

Question 9

population inversion

Answer 9

the number of excited atoms outweighs the number at ground state

Question 10

pumping

Answer 10

the application of an external source of power to the lasing medium
causes population inversaion

Question 11

what are the 5 ways to produce a laser?

Answer 11

pumping of active medium
population inversion
spontaneous emission
stimulated emission
amplification

Question 12

coherence

Answer 12

same wavelength and all in phase

light is emitted in an organized fashion rather than randomly as in a light bulb

Question 13

monochromatic

Answer 13

single color, same wavelength

Question 14

collimation

Answer 14

photons move in a parallel fashion, they don’t diverse

Question 15

wavelength

Answer 15

longer (lower frequency)= deeper penetration

Question 16

name the types of lasers

Answer 16

gas
solid
semiconductor
liquid

Question 17

types of gas, liquid and solid lasers

Answer 17

helium-neon gas in lasing chamber

Question 18

semiconductor laser

Answer 18

tow layers of material in silicon matrix

layer inteface is reflective

Question 19

what helps determine the depth of penetration?

Answer 19

melanin or hemoglobin increase, the depth of penetration of the light decreases
the wavelength of the light will determine the overall depth of penetration the photons will attain

Question 20

application of laser

Answer 20

laser should be in light contact with patient
90 degree angle to the treatment area
cover each square centimeter of the treatment area

Question 21

what is the alternate method of application?

Answer 21

scanning technique
hold laser 5-10m from skin
energy level decreases with distance
alter intensity to take that into account

Question 22

photobiomodulation

Answer 22

effect is from absorption of photons of light by cells

Question 23

photobiostimulation

Answer 23

lower doses of laser

Question 24

photobioinhibition

Answer 24

higher doses of laser

Question 25

chromophores

Answer 25

molecules which accpet energy from photons | cytochromes

Question 26

cytochromes are located where?

Answer 26

in mitochrondria sensitive to light photons absorption of photons triggers biochemical reactions

Question 27

cellular mechanisms of laser

Answer 27

changes in Na-K channel increase intracellular calcium the calcium flux affects the level of cyclic nucleotides, which modulate DNA and RNA synthesis, which modulates cell proliferation

Question 28

biological effects of low level laser therapy

Answer 28

enhancement of ATP synthesis stimulated vasodilation via increased histamine, NO and serotonin beneficial acceleration of leukocytic activity converting prostaglandin into prostacyclin reduction in interkeukin-1 enhanced lymphocyte response temperature modulation stabilization of cellular membrane

Question 29

mechanism of biological effects of laser

Answer 29

photons absorbed by the tissues stimulates metabolic processes and cell proliferation through synthesis of nucleic acids and enhanced cell division alter molecular level activity

Question 30

photostimulation (photobiomodulation)

Answer 30

the process where a chain of chemical reactions is triggered by exposure to light

Question 31

stimulation of the respiratory electron transport chain results in 2 major events

Answer 31

light changes the reduction/oxidation status of the mitochondria which leads to enhanced ATP synthesis the activation of sodium/potassium pump alters the cell membrane permeability to flow of claicum

Question 32

what are the primary effects of photobiostimulation?

Answer 32

direct interaction of photons with cytochromes

Question 33

what are the secondary effects of photobiostimulation?

Answer 33

occur in the same cell in which photons produced the primary effects induced by primary effects cel proliferation protein synthesis degranulation growth factor secretion myofibroblast contraction and neurotransmitter modification depending on the cell type and its sensitivity

Question 34

tertiary effects of photobiostimulation

Answer 34

are the indirect responses of distant cells to change in other cells that have interacted directly with photons least predictable

Question 35

indications

Answer 35

``` wound healing TMD myofascial pain osteoarthritis RA tendinopathy trigger points epicondylitis neck and low back pain ```

Question 36

class I FDA classification

Answer 36

safe under reasonably foreseeable use

Question 37

class 1M

Answer 37

safe except when used with optical aids

Question 38

Class II

Answer 38

hazardous if directed continually into the eye

Question 39

class III

Answer 39

moderate risk to retina but not to the skin or tissues. operator and patient must wear protective eye wear

Question 40

class IV

Answer 40

can cause damage to eyes, skin burns, fire hazard

Question 41

contraindication for laser therapy

Answer 41

``` cancer pregnancy direct exposure to eyes areas of active hemorrhage over the thyroid gland directly over open wounds, unless covered with a clear protective barrier epileptic patients ```

Question 42

super pulsed laser

Answer 42

pulses or bursts of energy with higher peak power and less thermal effects

Question 43

stimulatory frequencies

Answer 43

lower frequencies are termed biostimulatory

Question 44

arndt schultz principle

Answer 44

biological reactions are not only dictated by dose, but the rate at which the energy is delivered