This presentation gives a brief introduction to the characteristics of laser devices. Absorption, tissue penetration and physiological mechanisms of laser irradiation are discussed. The biological effects of low power laser light are reviewed in the areas of collagen metabolism, wound healing, inflammation and pain control. Contraindications, precautions and side effects of low power laser irradiation are discussed.

1. B Y : R A A N A K A R I M P O U R
LASER APPLICATIONS
TO MEDICINE
Bachelor, Department of cellular and molecular
biology, Faculty of advanced science and
technology, Tehran Medical Sciences, Islamic
Azad University, Tehran, Iran

2. INTRODUCTION
• This presentation gives a brief introduction to the
characteristics of laser devices.
• Absorption, tissue penetration and physiological
mechanisms of laser irradiation are discussed.
• The biological effects of low power laser light are
reviewed in the areas of collagen metabolism,
wound healing, inflammation and pain control.
Contraindications, precautions and side effects of
low power laser irradiation are discussed.
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3. LAYOUT
laser
Basic
components Types
Medical
applications
Types of
medical
lasers
Fundamentals
of laser
Principles of
medical
lasers
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4. BASIC CONCEPT
• L.A.S.E.R is an acronym for
LIGHT
AMPLIFICATIONS
by
STIMIULATED
EMISSION
of
RADIATION
• Which means the photons are amplified by the
physical processes of the laser design.
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5. BASIC CONCEPT
• Laser is a narrow beam of light of a single
wavelength (monochromatic) in which each wave
is in phase (coherent) with other near it.
• Laser apparatus is a device that produce an intense
concentrated, and highly parallel beam of
coherent light
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8. BASIC THEORY FOR LASER
• Atom composed of a nucleus and electron
cloud
• If an incident photon is energetic enough, it
may be absorbed by an atom, raising the
latter to an excited state.
• It was pointed out by Einstein in 1917 that an
excited atom can be revert to a lowest
state via two distinctive mechanisms:
1. spontaneous emission
2. stimulated emission
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9. SPONTANEOUS EMISSION
• Each electron can drop back
spontaneously to the ground state emitting
photons.
• Emitted photons bear no incoherent. It
varies in phase from point to point and
from moment to moment.
• e.g. emission from tungsten lamp.
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10. H T T P S : / / U P L O A D . W I K I M E D I A . O R G / W I K I P E D I A / C O M M O N S / 1 / 1 4 / S P O N T A
N E O U S E M I S S I O N . P N G
SPONTANEOUS EMISSION
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11. STIMULATED EMISSION
• Each electron is triggered into
emission by the presence of
electromagnetic radiation of the
proper frequency. This is known as
stimulated emission and it is a key to
the operation of laser.
• e.g. emission from Laser
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12. H T T P S : / / U P L O A D . W I K I M E D I A . O R G / W I K I P E D I A / C O M M O N S / T H U M B / 0 / 0 9 /
S T I M U L A T E D _ E M I S S I O N . S V G / 5 5 0 P X - S T I M U L A T E D _ E M I S S I O N . S V G . P N G
STIMULATED EMIISION
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13. H T T P S : / / W W W . R E S E A R C H G A T E . N E T / P R O F I L E / R O D R I G O _ D E _ M A T O S / P U B L I C A T I O N / 3 2 2 8 6 1 3 0 5 / F I
G U R E / F I G 2 / A S : 5 8 9 2 2 7 2 2 1 8 6 4 4 4 8 @ 1 5 1 7 4 9 4 1 2 5 3 0 4 / A B S O R P T I O N - S P O N T A N E O U S - E M I S S I O N -
A N D - S T I M U L A T E D - E M I S S I O N - 1 7 . P N G
BRIEFLY
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14. TYPES OF LASERS:
Lasers are classified according to laser active
medium into:
• Solid: for example :
• Ruby (Cr:Al2O3)
• Neodymium- glass (Nd-Glass).
• Nd- YAG (Nd-Yttrium, Aluminum granite)
• Liquid lasers: (Dyes).
• Gas lasers: He-Ne, Ar, CO2, He-Cd, N2, Kr,
Excimer (ArF, XeF, HF, DF).
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15. RUBY
Nd-glass laser
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16. DYES LASER
H T T P : / / T E C H N O L O G Y . N I A G A R A C . O N . C A / S O P / I M A G E S / N C D Y E L A S E R . J P
G
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17. MEDICAL LASER
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18. MEDICAL LASER
• In the medical field, dermatology, opthalmology
and endoscopicsurgery had been the main areas
employing the useof lasers so far. This has been
especially true for the high power or hot lasers.
• The use of the low power, cold or softlasers is
gaining increasing popularity within physical
therapy.
• The clinical application of the low output laser
encompasses areas concerned with acute and
chronic pain reduction, enhanced tissue healing
and regeneration, and acupuncture therapy
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19. HISTORY
• Goldman (1962)
• McGuff (1963)
• Endre Mester (1967)
• Choy and Ginsburg (1983)
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20. PRINCIPLE OF MEDICAL LASERS
• THE RIGHT WAVELENGTH
• THE RIGHT AMOUNT OF LASER ENERGY
• GETTING THE LASER ENERGY THERE:
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21. CLASSIFICATION
• Laser in medicine can be classified into two general
groups:
1. High power (hot) laser
2. Low power( cold, soft) laser
The difference is based on the optical energy of the
laser.
Low power lasers carry 1-4 J energy and they are
known as :
-LPLT
-LILT
-LLLI
-cold laset therapy
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22. USE OF LASER THERAPY
Anti inflammatory
Analgesic effects
Anti edema effects
Bio stimulating effects
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23. LASER APPLICATION IN SURGERY
• Surgical applications include urology,
cardiovascular and veterinary surgery.
• Lasers offer an advantage because the high
intensity can cut tissue and coagulate blood at the
same time
• Researchers have demonstrated that laser surgery
results in the removal of much less tissue than
traditional procedure, improving patient recovery.
• USES LASERS: DIODE LASERS, ND-YAG LASER,ARGON
LASER
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24. A.Lymphangioma of tongue with
recurrent bleeding.
B. Three months following ND:YAG
LASER therapy. Marginal 3 cm of
tongue treated by spot technique.
Central portion of tongue untreated
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25. A. A 5-cm
diameter
superficial
hemangioma
of lesser
curvature of
the stomach
with recurrent
bleeding.
B.Immediately
following
ARGON
LASER
photocoagulati
on of
hemangioma.
No recurrence
after 3 years
follow-up.
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26. LASER APPLICATION IN DENTISTRY
• Lasers have been used in dentistry since 1990s to
treat a number of conditions. The acceptance of
the laser technology has been growing, although it
is still a subject of active research.
• Lasers have been demonstrated in treatment of
tooth decay, gum disease, biopsies, removing of
lesions, activating a bleaching solution for whitening
teeth and curing of dental composites.
• USES LASERS: DIODE LASER MODULES, Cold
laser,CO2 laser
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27. H T T P : / / I M G . M E D I C A L E X P O . C O M / I M A G E S _ M E / P H O T O - G / 7 1 3 0 0 -
8 5 1 2 2 4 0 . J P G
DIODE LASER
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28. LASER APPLICATION IN
DERMATOLOGY
• Skin resurfacing and rejuvenation techniques work
by targeting water absorption in the mid-IR to heat
and ablate tissue or by subtle thermal effects,
stimulating a wound healing response.
• These applications cover a variety of conditions,
including wrinkle removal, sun damaged skin, age
spots and acne spots
• While both ablative and ablative techniques are
uses, the latter are growing in popularity.
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29. CO2 LASER
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30. LASER APPLICATION IN UROLOGY
Benign prostatic hyperplasia is a urological
condition that is caused by an enlarged
prostate gland. Surgeons use a laser to
remove the prostate tissue and improve
flow into the urethra. IPG’s Thulium fiber
laser has demonstrated positive outcomes
for this application.
Another widespread urological application is lithotripsy. Ho:YAG
laser is de facto standard of care for this procedure, whereas
potential of QCW thulium fiber laser is currently being explored.
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31. H T T P : / / I M A G E B A N K . O S A . O R G / G E T I M A G E . X Q Y ? I M G = Q C 5 S Y X J N Z S X V Z S 0
Y M C 0 X N I 0 X N Z U Z O S 1 N M D A X
THULIUM FIBER LASER
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32. LASER APPLICATION IN AIRWAYS
• Laser photoresection of central airway obstruction is a useful
tool for an Interventional Pulmonologist (IP).
• Endobronchial therapy of the malignant airway obstruction is
considered as a palliative measure or a bridge therapy to the
definite treatment of cancer. Several ablative therapies such
as electrocautery, argon plasma coagulation (APC),
cryotherapy and laser photoresection exist in the
armamentarium of IP to tackle such presentations.
• Besides Neodymium-Yttrium, Aluminum, Garnet (Nd:YAG)
laser, there are several different types of laser that have been
used by the pulmonologist with different coagulative and
cutting properties. This chapter focuses on the historical
perspective, current status, and potentials of lasers in the
management of central airway lesions.
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33. Today There Are Several Different Types Of Laser
Available For Their Application In The Endobronchial Tree
Laser Waveleng
th (nm)
Delivery
device
Depth of
penetratio
n (mm)
Coagulati
on effect
Cutting
effect
Argon 516 Quartz
fiber
1.0–2.0 ++ +
KTP 532 Quartz
fiber
1.0 ++ +
Diode 808 Quartz
fiber
1.0 ++ +++
Nd:YAG 1,060 Quartz
fiber
0.5–1.5 +++ +
Nd:YAP 1,340 Quartz
fiber
0.5–1.0 ++++ +
Ho:YAG 2,100 Quartz
fiber
0.5 +++ ++
CO2 10,600 Coupler
and
waveguid
e
0.23 + +++
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34. LASER HAZARDS
https://www.rp-photonics.com/img/safety_issues.png 34Raana Karimpour

35. CONCLUSION
• The biomedical effects of low power laser
irradiation have been investigated in various other
areas. Some of the more interesting settings include
immunosupression-immunostimulation, autoimmune
disease, and nerve regeneration.
• However, little published work exists with respect to
these and greater efforts have to be made to insure
their validity and further development.
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36. REFERENCES
• Papers:
 Thiel, Haymo. "Low power laser therapy—an introduction and a
review of some biological effects." The Journal of the Canadian
Chiropractic Association 30.3 (1986): 133.
 Dixon, John A. "Current laser applications in general
surgery." Annals of surgery 207.4 (1988): 355.
 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5220034/
 Choy, D. S. J. "History of lasers in medicine." The Thoracic and
cardiovascular surgeon 36.S 2 (1988): 114-117.
• Books:
 Journal of Lasers in Medical Sciences
Sites:
https://www.ipgphotonics.com/en/applications/medical/surgery
http://sbmu.ac.ir/index.jsp?fkeyid=&siteid=150&pageid=274
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37. THANK YOU
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