際際滷

際際滷Share a Scribd company logo
Microwave diathermy
DR. HETVI JAIMIN SHUKLA
PT IN NEUROLOGICAL SCIENCES
Microwave diathermy.pptx
INTRODUCTION
 Microwave diathermy  between short wave diathermy and infrared radiation
 Penetration not deep as SWD
 Generate strong electric field with weak magnetic field
 Higher frequency and smaller wavelength than SWD
 1 m to 1 mm  300 MHz to 300 GHz
Frequency (MHz) Wavelength (cm)
2450 12.2
915 32.8
434 69.1
PRODUCTION OF MICROWAVES
 Antenna  a wire which produce EMR
 Magnetron  generates higher power level alternating current to antenna as well
as different frequency ; different magnetron
 A wire  attached with metal reflector
 A delay switch  to allow time for the magnetron to reach its proper working
temperature
 A standby switch  without switching off magnetron treatment can be varied.
 Continuous or pulsed mode
Microwave diathermy.pptx
PHYSIOLOGICAL EFFECTS ON
TISSUES
 Heating = absorbed radiation  layered tissue heating
THE PATTERN OF MICROWAVE
ABSORPTION IN THE TISSUE
 Absorption  penetration depth is small
 At 2450 MHz, reflection with skin and fat thickness from 50-75%
 Due to reflection, more superficial heating than expected.
MORPHOLOGICAL EFFECTS
EFFECTS OF EMITTER SHAPE
HEATING EFFECT
 15 minutes MWD will prolong heating in to deep muscles upto more 20
minutes
 the theoritical absorptionpattern indicates absorption in the skin, fat,
muscle
 the widely used 2450 MHz has a less satisfatory absorption pattern for
therapeutic purpose than lower frequencies
 the shape and size of the emitter influences the energy distribution on to
the tissue
 higher transmission - contact emitter
 few cm in tissue heating
 2450 MHz increses blood flow more.
THERAPEUTIC USES
 Deep tissue heating  ant. Part of wrist and knee
METHODS OF APPLICATION
 STAGES :
1. Patient  explanation and examination
2. Apparatus
3. Preparation of part
4. Setting up
5. Instructions and warnings
6. Application
7. Termination
DOSAGE
 Intensity  200 mW/cm2
 SAR  specific absorption rate  W/Kg
 50-170 W/Kg
 Duration  15- 20 min minimum
POTENTIAL DANGERS
 Effects of metal
 Effects of changed blood flow
 Effects of surface moisture
 Implanted electronic equipment
 The eyes
 The testes
 Pregnancy
 Other local pathologies
GENERAL SAFETY WITH MICROWAVES

More Related Content

Microwave diathermy.pptx

  • 1. Microwave diathermy DR. HETVI JAIMIN SHUKLA PT IN NEUROLOGICAL SCIENCES
  • 3. INTRODUCTION Microwave diathermy between short wave diathermy and infrared radiation Penetration not deep as SWD Generate strong electric field with weak magnetic field Higher frequency and smaller wavelength than SWD 1 m to 1 mm 300 MHz to 300 GHz Frequency (MHz) Wavelength (cm) 2450 12.2 915 32.8 434 69.1
  • 4. PRODUCTION OF MICROWAVES Antenna a wire which produce EMR Magnetron generates higher power level alternating current to antenna as well as different frequency ; different magnetron A wire attached with metal reflector A delay switch to allow time for the magnetron to reach its proper working temperature A standby switch without switching off magnetron treatment can be varied. Continuous or pulsed mode
  • 6. PHYSIOLOGICAL EFFECTS ON TISSUES Heating = absorbed radiation layered tissue heating
  • 7. THE PATTERN OF MICROWAVE ABSORPTION IN THE TISSUE Absorption penetration depth is small At 2450 MHz, reflection with skin and fat thickness from 50-75% Due to reflection, more superficial heating than expected.
  • 10. HEATING EFFECT 15 minutes MWD will prolong heating in to deep muscles upto more 20 minutes the theoritical absorptionpattern indicates absorption in the skin, fat, muscle the widely used 2450 MHz has a less satisfatory absorption pattern for therapeutic purpose than lower frequencies the shape and size of the emitter influences the energy distribution on to the tissue higher transmission - contact emitter few cm in tissue heating 2450 MHz increses blood flow more.
  • 11. THERAPEUTIC USES Deep tissue heating ant. Part of wrist and knee
  • 12. METHODS OF APPLICATION STAGES : 1. Patient explanation and examination 2. Apparatus 3. Preparation of part 4. Setting up 5. Instructions and warnings 6. Application 7. Termination
  • 13. DOSAGE Intensity 200 mW/cm2 SAR specific absorption rate W/Kg 50-170 W/Kg Duration 15- 20 min minimum
  • 14. POTENTIAL DANGERS Effects of metal Effects of changed blood flow Effects of surface moisture Implanted electronic equipment The eyes The testes Pregnancy Other local pathologies
  • 15. GENERAL SAFETY WITH MICROWAVES