This document discusses the various medical applications of lasers. It begins by defining what a laser is and providing some basic concepts. It then outlines several uses of lasers in medicine such as ophthalmology, dermatology, cancer treatment, surgery, and more. Specific applications discussed in more detail include laser eye surgery to correct vision, using lasers to treat retinal diseases and birthmarks, laser angioplasty, laser hair removal, and laser treatments for cancer. The document also covers laser safety classifications and provides references used.

1. Laser
Applications In
Medical Field
Group 01
1

2. FIRST OFF WHAT DOES
LASER STAND FOR?
LIGHT
AMPLIFICATION BY
STIMULATED
EMISSION OF
RADIATION
2

3. Basic
Concepts:
01
02Laser 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.
3

4. USES OF
LASER
TECHNOLOGY
INCLUDING:
 Science
 Machining
 Communications
 Security/military
 Medicine
4

5. Historical Introduction
1946: A German
physician, Gerd Meyer,
used the sun to treat
detached retinas and
destroy tumors in some
of his patients eyes.
1961: one year after
Maiman built the first laser,
Milton Zaret used laser to
produce ocular lesions in
animals.
1948: High intensity
xenon lamp used for
photocoagulation
1963: Chris Zweng
treated retinal disease in
his patients using laser
beam
5

6. TREATMENT &
DIAGNOSTIC BY LASER
6

7. Introduction
Laser are presently used for a variety of application in the
medical field .This is the interaction between the laser radiation
and human tissue.
Success of this depends on :
-Radiation
-Wavelength
-Ability of the tissue to absorb
-Total energy incident on the tissue and area to be treated

8. When a laser beam
projected to tissue
Five Phenomena
• reflection,
• transmission,
• scattering,
• re-emission,
• absorption.
• Laser light interacts with tissue and
transfers energy of photons to tissue
because absorption occurs
7

9. Photocoagulation
• A slow heating of muscle and other tissues is
like a cooking of meat in everyday life.
• The heating induced the destabilization of the
proteins, enzymes.
• This is also called coagulation.
• Like egg whites coagulate when cooked, red
meat turns gray because coagulation during
cooking.
• A Laser heating of tissues above 50 oC but
below 100oC induces disordering of proteins
and other bio-molecules, this process is called
photocoagulation.
What is a coagulation?
8

10. Lasers in Medicine
Types of lasers used
in medicine include in
principle any laser
design, but
especially:
• CO2 lasers
• Diode lasers.
• Dye lasers
• Excimer lasers
• Fiber lasers
• Gas lasers
• Free electron lasers
• Optical parametric oscillators
9

11. Medical Areas that employ Lasers
05
06
• Angioplasty
• Cancer diagnosis
• Cancer treatment
• Dermatology
• Lithotripsy
• prostatectomy
• Cosmetic applications such as laser hair removal,
tattoo removal, and laser liposuction
• Medical imaging
• Microscopy
• Ophthalmology (includes Lasik and Laser
photocoagulation)
• Optical coherence tomography
• Surgery
06
10

12. • Laser surgery, pioneered by Russia, is surgery using a laser (instead of a scalpel) to
cut tissue.
• Examples include the use of a laser scalpel in otherwise conventional surgery, and soft
tissue laser surgery, in which the laser beam vaporizes soft tissues with high water content.
LASER SURGERY
• Laser resurfacing is a technique in which molecular
bonds of a material are dissolved by a laser.
• Laser surgery is commonly used on the eye.
• Techniques used include LASIK, which is used to correct
near and far-sightedness in vision, and phorefractive
keratectomy, a procedure which permanently reshapes the
cornea using an excimer laser to remove a small amount
of tissue.
• Types of surgical lasers include
• carbon-dioxide, argon, Nd:YAG, and KTP.
11

13. • Various types of laser surgery are used to treat refractive error:
• LASIK , in which a knife is used to cut a flap in the cornea, and a
laser is used to reshape the layers underneath, to treat refractive
error INTRALASIK, a variant in which the flap is also cut with a
laser.
• Photorefractive keratectomy(PRK, LASEK), in which the cornea is
reshaped without first cutting a flap
• Laser thermal keratoplasty, in which a ring of concentric burns is
made in the cornea, which cause its surface to steepen, allowing
better near vision
Eye surgery 12

14. Laser Eye
Surgery
13

15. Retina Treatment
 The dark brown melanin pigment
of the retina absorb the green
beam of the argon laser.
 The argon laser can destroy
specific regions of the retina
without harming the other area of
the eye, which absorb different
wavelength of light.
14

16. Ophthalmology
LASER has particular use in ophthalmology
because the eye can be used as an optical
optical device. The transparency of the front
part of the eye, the cornea, allows light such
as LASER to reach almost all the tissues of
the eye.
Argon laser treatment can be used to
treat a number of eye conditions including
glaucoma, diabetic eye diseases and some
retinal holes and tears.
15

17. Red birthmarks (Port wine stains)
• Red birthmarks also absorb the
argon laser, which could be blue
or green depending on its
wavelength.
• The absorbed light destroys
hundreds of the extra blood
vessels that beneath the skin’s
outer layer and discolor it.
16

18. • R. Rox Andrson and
A. Jhon (1983)
(Harvard University)
suggested that short
exposure less than 1
ms – to intense light
would destroy the
absorption site but
produce little or no
damage to adjacent
tissue.
• The heat generated
by the beam can
sometimes spread
to parts of the skin
other than the
abnormal blood
vessels and cause
scarring or loss of
pigments.
Disadvantages 17

19. Laser Angioplasty
• The removal of plaque in obstructed vessel
by laser, administrated through a fiber optics.
• Fluorescence characterization of the vessel
wall could be performed via the same fiber
as that used for the delivery of high-power
pulses for plaque removal.
18

20. Facial laser resurfacing uses
high energy ,pulsed and
scanned Lasers. Pulsed co2
and erbium : YAG lasers have
been successful in reducing
and removing facial wrinkles ,
acne scars and sun damaged
skin.
Dermatology with Laser 19

21. Laser Hair Removal
Laser hair removal is
the process of hair
removal by means of
exposure to pulse of
laser light that
destroy the hair
follicle.
It had been performed
experimentally for
about twenty years
before becoming
commercially available
in 1995 and 1996.
20

22. Laser Liposuction Laser liposuction is a minimally
invasive cosmetic procedure that uses
a laser to melt away fat under the
skin.it is also called laser lipolysis.
21

23. Laser therapy uses a very narrow ,focused beam of light to shrink or
destroy cancer cells.it can be used to cut out tumors without
damaging other tissue. Laser therapy is often given through a
thin ,lighted tube that is put inside the body. Thin fibers at the end of
the tube direct the light at the cancer
Laser Cancer
Treatment
22

24. Laser in Neurosurgery
Carbon di –oxide lasers have been used in
neurosurgery for the treatment of brain
tumors since the 1970s.
- Laser tissue welding is a method of
creating an instant water tight wound
closure inside the skull and spine.
23

25. The removal of lower gastro
intestinal fats. Nd YAG laser
are mostly used. It is also
used to cure cancer. The
temperature of the tissue
does not increase.
Gastroenterology
24

26. 40% 50%60%80%
01
02
03
04
• emit visible light at higher levels than Class 1,
• eye protection is provided
• can be hazardous if the beam is viewed directly with
optical instruments;
Class 2 and 2M (magnifier)
These are considered safe
Class 1 and 1M (magnifier) lasers
produce visible and invisible light that are
hazardous under direct viewing conditions
Class 3R (Restricted) Laser
• produce visible or invisible light that is
hazardous under direct viewing conditions
• they are powerful enough to cause eye
damage in a time shorter
• Laser products with power output near
the upper range of Class 3B may also
cause skin burns
Class 3B lasers
Lasers are classified according to the hazard
25

27. References
• Duarte F.J.;Hillman,L.W.(1990).Dye Laser Principles,with
Applications.Boston:Academic Press.ISBN 0-12-222700-x.
• http://en.m.wikipedia.org//wiki/Laser_medicine
• https://medlineplus.gov/ency/article/001913.htm
• https://www.modulight.com/applications-medical/
26

28. Thank You
27

29. Group Members
• M.P.P.Chethiya - 16APP2642
• W.A.D.Chathuranga - 16APP2652
• H.P.S.Harishchandra - 16APP2662
• A.G.M.Sachinthana - 16APP2671
28