This document discusses laser therapy, including its production, types, effects, applications, and techniques. It begins by defining laser as light amplified by stimulated emission of radiation. It then describes the key properties of lasers as monochromaticity, coherence, and collimation. It discusses the different types of lasers based on lasing medium (ruby, HeNe, diode) and intensity (high power, low power). The physiological and therapeutic effects of lasers are outlined, including effects on wound healing, pain relief, and inflammation. Applications such as wound healing and reducing pain and inflammation are indicated. The document concludes by describing techniques for laser application and important parameters like wavelength, energy density, and dosage.

1. LASER
KEERTHI PRIYA MPT NEURO,
ASSISTANT PROFESSOR

2. CONTENTS
INTRODUCTION
PRODUCTION
TYPES
TECHNIQUE OF APPLICATION
PHYSIOLOGICAL EFFECTS
THERAPEUTIC EFFECTS
INDICATIONS
PRECAUTIONS

3. LASER: LIGHT AMPLIFICATED STIMULATED EMISSION OF
RADIATION.
DEFINITION: A device that concentrates high energies into a narrow beam of
coherent & monochromatic light.
USES :
Light Shows
Surgeries
Super Market
Physiotherapy Department
PROPERTIES OF LASER:
1. Monochromaticity
2. Coherence
3. Collimation
INTRODUCTION

4. PROPERTIES OF LASER
INTRODUCTION
MONOCHROMATICITY:
CHROMA=COLOUR
Emitted rays have single colour
of same wavelength & frequency

5. PROPERTIES OF LASER
INTRODUCTION
COHERENCE
Maintain same phase of crest & troughs.
1. Spatial : waves travel in same direction
2. Temporal : Electric & magnetic field
occurs in same time

6. PROPERTIES OF LASER
INTRODUCTION
COLLIMATION
Decreased or no divergence of
the waves as they travel parallel
to each other.

7. PRODUCTION
PRINCIPLE: Production of laser is based on quantum theory
QUANTUM THEORY
Heating of an atom
Molecular collision
takes place
Electrons move
from outer to inner
shells.
Electrons are
unstable &
spontaneously
energy is released
as photon.
Metastable
electrons photons
collide and gives
an identical photon
.
Stimulated
emission

9. COMPONENTS FOR PRODUCTION
OF LASER
PRODUCTION
LASING MEDIUM
Materials which absorbs external
energy and gives off the energy
as photons
ENERGY SOURCE
Flash gun is used to excite
electrons in lasing medium.
RESONATING CHAMBER
Lasing medium surrounded by 2
reflecting surfaces at either ends.
One end with complete reflection &
other with partial reflection

10. BASED ON TYPE OF LASING
MEDIUM
1. RUBY LASER
2. HE NE LASER
3. DIODE LASER
BASED ON INTENSITY OF
ENERGY
CLASSIFICATION
1. HIGH POWER LASER
2. LOW POWER LASER

11. BASED ON LASING MEDIUM
CLASSIFICATION
RUBY LASER : CRYSTAL LASER
Synthetic ruby rod made of Aluminium oxide is the
lasing medium. Xenon flash tube is coiled around the rod
is the flash gun.
Pulse mode
Wavelength= 694.3nm

12. BASED ON LASING MEDIUM
CLASSIFICATION
HE NE LASER
Long tube filled with inert gas at low pressure
surrounded by a flash gun.
Can be used in contact with skin by optical guide/
fibre optic cable
Wave length= 632.8nm
Direct penetration=2-5mm
Indirect penetration=10-15mm

13. BASED ON LASING MEDIUM
CLASSIFICATION
DIODE LASER: SEMICONDUCTOR
LASER
Light emitting diode made of gallium
aluminium arsenide.
Wave length= 904nm
Direct penetration=1-2cm
Indirect penetration=5cm

14. BASED ON INTENSITY OF ENERGY CLASSIFICATION
HIGH POWER LASER
• Also called as HOT LASER
• Therapeutic response is achieved
due to heat.
Used in
• surgeries
• Dermatology
• Ophthalmology
• Oncology & vascular
LOW POWER LASER
Also called as THERAPEUTIC
LASER
Used in
• Wound healing
• Pain
• Inflammation

15. FDA CLASSIFICATION OF LASER CLASSIFICATION
CLASS I EXCEMPT
Non hazardous
Power<1mw
GaAs: 820-910nm
CLASS III MODERATE RISK
Hazardous
Eye damage
No skin damage
CLASS II LOW POWER
Hazardous
Power=1mw
HeNe
CLASS IV HIGH POWER
Combustion effect
Damages retina and skin

16. EFFECTS OF LASER
REFLECTION
LASER light is reflected based
on wave length & nature of
tissue & incidence angle
ABSORPTION
Absorbed by cytochromes &
macrophages.
SCATTERING &
PENETRATION
Scattering is due to divergence,
reflection & refraction.
Penetration by
Red light is 1-2mm.
Infrared rays is 2-4mm

17. PHYSIOLOGICAL
EFFECTS
 Altered cell proliferation & cell motility
 Alteration of cell membrane potentials
& AP
 Altered prostaglandin production &
endogenous opoid production

18. PHYSIOLOGICAL
EFFECTS
 Activation of phagocytes
 Activation & proliferation of fibroblasts
 Stimulation of immune responses,
macrophages & mast cell
degranulation
 Stimulation of angiogenesis

19. THERAPEUTIC
EFFECTS
 Wound Healing
 Pain relief
 Immunological response
 Inflammation

20. WOUND
HEALING
Activation of
chromophores
Stimulation of
fibroblast
Increased
production of
connective
tissue
Increased
intra cellular
substances
Increased
mitochondria

21. PAIN RELIEF
 Decreased sensory nerve conduction
 Increased healing
 Anti-inflammatory effect
 Increased neuro-humoral response

22. IMMUNOLOGICAL
RESPONSE
LEUCOCYTE
ACTIVATION
INCREASED
PHAGOCYTIC
EFFECT
BACTERIAL
DESTRUCTION

23. INFLAMMATION
Inhibits
prostaglandin
production
Decreased
prostaglandin
Blood vessel
are normal
Decreased
flow of
plasma over
interstial
space

24. INDICATIONS
 Facilitate wound healing
 Pain reduction
 Increasing the tensile strength
of a scar
 Decreasing scar tissue
 Decreasing inflammation
 Bone healing and fracture
consolidation
CONTRAINDICATIONS
Directly Over Eyes
Pregnancy
Cancerous Growths

25. TECHNIQUE OF APPLICATION
PREPERATION OF
PATIENT
Explain procedure
Effects
Dangers
PREPERATION OF
APPARATUS
Selection of appropriate
apparatus
PREPERATION OF
TREATMENT AREA
clean the area with
alcohol.
Comfortable position

26. TECHNIQUE OF APPLICATION
APPLICATION
• Focus the laser over treatment area
• Adjust the parameters
• Turn on
• Choose the lasing medium
• Wear protective gogles
TERMINATION
• Check the area after
treatment .
• Note down if patient
complains anything

27. DOSAGE
WAVE LENGTH
Superficial =Red Visible
Musculoskeletal= Infra
Red Spectrum
ENERGY DENSITY
POWER OUTPUT AND
AREA
POWEROUTPUT=
E.D=1-10J/cm
OPENWOUND=4J/CM
OUTPUT
PULSE
CONTINOUS
LASING TECHNIQUE
GRID
SCAN

29. REFERENCES
 ELECTROTHERAPY EXPLAINED BY LOW & REED
 CLAYTONS ELECTROTHERAPY
 THERAPEUTIC FOR SPORTS MEDICINE AND ATHLETIC TRAINING MODALITIES BY W
I L L I A M E . P R E N T I C E