TYPES OF DIATHERMY Shortwave Diathermy SWD 2 Microwave

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TYPES OF DIATHERMY Shortwave Diathermy (SWD) 2. Microwave Diathermy(MWD) 3. Ultrosonic Diathermy 1.

TYPES OF DIATHERMY Shortwave Diathermy (SWD) 2. Microwave Diathermy(MWD) 3. Ultrosonic Diathermy 1.

MICROWAVE DIATHERMY Microwave Diathermy (MWD) is a high frequency electromagnetic radiation lies between infrared

MICROWAVE DIATHERMY Microwave Diathermy (MWD) is a high frequency electromagnetic radiation lies between infrared and shortwave. Their frequency ranges between 300 -3000 MHz, with corresponding wavelengths of 1 m-10 mm. Frequency MHz Wavelength Cm 2450 12. 33 915 32. 7 433. 9 69

MICROWAVE DIATHERMY GENERATOR Power supply � Magnetron � Timing circuit � Applicators (emitter, a

MICROWAVE DIATHERMY GENERATOR Power supply � Magnetron � Timing circuit � Applicators (emitter, a director) �

MAGNETRON � The high frequencies of micro-thermy are obtained from the magnetron, which is

MAGNETRON � The high frequencies of micro-thermy are obtained from the magnetron, which is perforated with tiny holes, through which the electrons flow into the treatment heads. � The special design of the treatment heads shapes focuses the field directly at the target area. � The whole device is used to direct the waves onto the tissues.

EMITTER =APPLICATORS Applicator must be very flat to avoid reflection of energy. Diameter Temperature

EMITTER =APPLICATORS Applicator must be very flat to avoid reflection of energy. Diameter Temperature Circular shape Rectangular shaped 4 -6 inches 4. 5 X 5/ 5 X 21 inches Maximum at periphery of Maximum at central of radiation area each radiation area

Principle Related To Use Of MWD v Deep heating modality v Emits strong electrical

Principle Related To Use Of MWD v Deep heating modality v Emits strong electrical field/ little magnetic field. v Depth of penetration is frequency dependent. v Produces much more localized & concentrated heating effect than SWD. v Providing a more shallow tissue heating effect, depends on the type of tissue involved. v Reflection Refraction Absorption,

Principle Related To Use Of MWD The effective depth of MWD penetration (half-value depth)

Principle Related To Use Of MWD The effective depth of MWD penetration (half-value depth) is about 4. 5 cm, so the depth of heating is intermediate between that of infrared radiation (2 cm) and short wave diathermy (>5 cm). v MWD are strongly absorbed by tissues with high fluid content are heated most, while penetrated by tissues with low fluid content (e. g. fat or bones). v Tissues with low water content (fat) are penetrated to a greater depth (half value thickness=3. 5 cm). v Tissue with high water content (muscle, blood) are penetrated to superficial depth (=0. 7 cm).

Principle Related to Use of MWD n The patients does not form apart of

Principle Related to Use of MWD n The patients does not form apart of the circuit in MWD, so no tuning is necessary as in SWD. n Transmits as free space radiation, so needs only one emitter (applicator). n No Metal should be within 4 feet of MWD, since it will interfere with the signal. n Spacing is required between the skin and the applicators with MWD, where the applicator on a short wave unit my be placed in contact with treatment area.

Physiological and Therapeutic Effects of MWD When the electromagnetic radiation of MWD enters the

Physiological and Therapeutic Effects of MWD When the electromagnetic radiation of MWD enters the body causes Ionic movement (vibration). Rotation of dipoled. Distortion of non-polar molecule Physiological effects Therapeutic effects Effects Effects Relief of pain and muscle spasm Promote healing Infection Increase the extensibility on on on metabolism blood supply nervous tissue muscular tissue sweat glands

Microwave Diathermy Advantages Operation of the machine is simple Comfortable for the patient Localized

Microwave Diathermy Advantages Operation of the machine is simple Comfortable for the patient Localized heat to small surfaces No overheating if precautions are followed Disadvantages Not for deep structures Heats only one aspect of the joint Risk of burn

Treatment Parameter of MWD The MWD requires warm-up period of magnetron to develop enough

Treatment Parameter of MWD The MWD requires warm-up period of magnetron to develop enough energy 4 minutes, to allowed the Spacing of Applicators n n For small treatment area is 2 -6 cm For large treatment area is 10 -15 cm Intensity of Treatment n n Sensation of warmth Feel no more than a mild comfortable warmth. Trim of Treatment: 20 -30 minutes Frequency of Treatment; daily or alternating days depending on n n Response to treatment Patients condition/availability

SHORTWAVE DIATHERMY

SHORTWAVE DIATHERMY

SHORT WAVE DIATHERMY § Def. : SWD is a modality that produces deep heating

SHORT WAVE DIATHERMY § Def. : SWD is a modality that produces deep heating via conversion of electromagnetic energy to thermal energy. The pattern of heat produced depend on: Freq. used. Type of SWD unit. Water content of the tissues.

§ Shortwave diathermy current freq. 10 – 100 MHz (The shortest radiofrequency wave is

§ Shortwave diathermy current freq. 10 – 100 MHz (The shortest radiofrequency wave is used in therapeutic diathermy. ) the commonly used in medical work having freq. of 27. 12 MHz with wavelength of 11 meters

 Modalities: either continuous or pulsed (PSWD). PSWD: application of series of short pulses

Modalities: either continuous or pulsed (PSWD). PSWD: application of series of short pulses of SWD so that short periods of SWD interrupted by gaps where there is no SWD. The pt. receives lower dose of SWD energy if compared with continuous SWD applied of the same time. The tissues will receive lower thermal load.

 SWD: produce both deep and sup. Tissue heating, under certain controlled conditions it’s

SWD: produce both deep and sup. Tissue heating, under certain controlled conditions it’s applied for 20 min at the max tolerable dose

TYPES OF SHORTWAVE DIATHERMY Induction Field Capacitive Field

TYPES OF SHORTWAVE DIATHERMY Induction Field Capacitive Field

INDUCTION FIELD DIATHERMY • Places the patient in the electromagnetic field • Current flowing

INDUCTION FIELD DIATHERMY • Places the patient in the electromagnetic field • Current flowing within the coil produces a rotating magnetic field • Magnetic field produces eddy currents in the tissues • Eddy currents cause friction that produce heat Selectively heats muscle Also referred to as: – Magnetic field diathermy • •

CAPACITIVE FIELD DIATHERMY • • • Uses the patient’s tissues as a part of

CAPACITIVE FIELD DIATHERMY • • • Uses the patient’s tissues as a part of the circuit The tissues’ electrical resistance produces heat Selectively heats skin – Muscle is heated via conduction from the adipose • Also referred to as “condenser field diathermy”

TYPES OF ELECTRODES Flexible pads: consist of metal electrode encased in rubber and produce

TYPES OF ELECTRODES Flexible pads: consist of metal electrode encased in rubber and produce an electrostatic field.

 • Space plates: consist of a rigid metal electrode encased in a Perspex

• Space plates: consist of a rigid metal electrode encased in a Perspex cover € electrostatic field.

 Coil or cable electrode consists of a wire with plugs at either end

Coil or cable electrode consists of a wire with plugs at either end creates electromagnetic field.

 • The monode : flat, rigid coil encased in plastic cover € electromagnetic

• The monode : flat, rigid coil encased in plastic cover € electromagnetic field.

 • The diplode : or drum electrode, consists of a flat coil electrode

• The diplode : or drum electrode, consists of a flat coil electrode encased in a Perspex cover with two wings € electromagnetic field

ULTRASOUND DIATHERMY Ø Ultrasound diathermy uses sound waves to treat deep tissues. Ø Heat

ULTRASOUND DIATHERMY Ø Ultrasound diathermy uses sound waves to treat deep tissues. Ø Heat is generated by the vibration of the tissue. Ø This promotes blood flow into the area. Ø It is used for many types of musculoskeletal sprains, strains, and fractures.

LONGWAVE DIATHERMY Ø Long wave diathermy is based on capacitor field method. ØIt can

LONGWAVE DIATHERMY Ø Long wave diathermy is based on capacitor field method. ØIt can work in heavy voltage fluctuation ØLong wave can be used as an alternative for shortwave diathermy applications. Ø it is portable and light weight.

DIATHERMY PROVIDES RELIEF IN: Ø ARTHRITIS ØBACK PAIN ØMUSCLE SPASMS ØNEURALGIA ØMYOSITIS ØSPRAINS AND

DIATHERMY PROVIDES RELIEF IN: Ø ARTHRITIS ØBACK PAIN ØMUSCLE SPASMS ØNEURALGIA ØMYOSITIS ØSPRAINS AND STRAINS ØTENDONITIS ØBONE INJURIES ØBURSITIS

UNWANTED EFFECTS OF DIATHERMY Ø The electromagnetic energy used in diathermy can cause extreme

UNWANTED EFFECTS OF DIATHERMY Ø The electromagnetic energy used in diathermy can cause extreme heat in metal devices such as bone pins, dental fillings, and metal sutures causing burns Ø During diathermy treatment, the patient becomes a part of the electrical field. Touching a bare metal object, such as a cabinet, during diathermy can cause a shock or burn.

RISKS ASSOCIATED WITH DIATHERMY Diathermy should be avoided in following cases: Ø Ø Ø

RISKS ASSOCIATED WITH DIATHERMY Diathermy should be avoided in following cases: Ø Ø Ø Ø implanted metal devices peripheral vascular disease tissue with restricted blood supply (ischemia) cancer bleeding disorders , wound dressings severe heart, liver, or kidney conditions pregnancy