What is Microwave Diathermy

 

MICROWAVE DIATHERMY

Microwave diathermy is the process of exposing tissues to radiation with a wavelength between infra-red and short-wave diathermic radiation, or radiation in the shorter wireless portion of the electromagnetic spectrum (Hertzian rays). Although definitions vary, waves between one and one hundred centimeters (cm) can be easily categorized as microwaves, or "decimeter" waves. In addition to radiation with a wavelength of 69 cm and a frequency of 433.92 MHz, radiation with a wavelength of 12.25 cm and a frequency of 2450 MHz is also commonly employed. When microwaves are applied to tissues, their main effect is to cause a localized increase in temperature where they are absorbed.

Production of microwaves

High-frequency currents generate wireless waves, which have the same frequency as the currents that cause them. The production principles of the currents are akin to those of other high-frequency currents; however, a unique kind of valve known as a magnetron is employed to achieve the required extremely high frequency. Similar to other valves, the magnetron takes some time to warm up, thus when the device is turned on, output is not instantly available. In order to prevent repetitive healing and cooling of the valves, a stand-by switch should be included for usage in between treatments. This allows the output circuit to be unplugged without turning off the current to the valves. such that a cable is used to transport the high-frequency cat. A coaxial cable is made up of a core wire and an outer metal sheath that is kept apart from the wire by an insulating substance. The circuit's output and return wires are formed by the wire and sheath, which are parallel to one another throughout. For that specific frequency, the cable must have the appropriate length. The current is sent by the coaxial cable to a tiny aerial, which emits microwaves. The reflector, in which the aerial is installed, is filled with a substance that transmits waves, creating a solid unit.

Role and Function of Microwave Emitters

The term "emitter," "director," or "applicator" refers to the entire apparatus that is utilized to direct the waves onto the tissues. The circuit is designed such that individual treatments don't require any adjustment; the patient is not a part of it. Since microwave radiation travels through open space, just one emitter is required. The microwaves will, nevertheless, be susceptible to absorption, refraction, reflection, and interference, just like any other pure electromagnetic radiation. Microwaves can interfere with radio communications, just like short-wave diathermy does. For this reason, the generator must be built to reduce interference, and only certain frequencies may be utilized for medical purposes. Among those allowed are 2450 MHz and 433.92 MHz, which correspond to wavelengths of 12.25 and 69 cm, respectively.

Application of microwaves

There are numerous kinds of emitters available. The most often utilized ones are positioned away from the body, allowing the waves to travel through the air between them and the tissues. These emitters might have a round or rectangular shape. The circular ones produce a cross-sectionally circular beam of rays that is denser on the periphery than in the center. The oval-shaped beam that the rectangular emitter produces has the highest density in the center. In both scenarios, the emitter's rays diverge, resulting in a decrease in ray density as the distance from the emitter grows. Ray absorption also contributes to the beam's decreased intensity.

Optimal Distance and Emitter Selection

The specific emitter, the generator's output, and the structure that has to be treated determine how far away from the skin these emitters should be utilized. Usually, it ranges from 10 to 20 mm. Greater distances are necessary for larger areas, while longer distances necessitate higher emitter outputs. Although they are designed to be used in close contact with tissues and to treat cavities, small emitters don't seem to work quite as well as distant emitters. Recently, 69 cm waves have been employed with an emitter that has a concave surface that fits around the body. This is said to have a more profound effect than the other approaches.

Physiological effects of microwaves

Heat is produced in the tissues as a result of the waves being absorbed, however microwave diathermy is different from previous heat treatments in that the heat penetrates the tissues more deeply. Unlike the electric field employed in short-wave diathermy, microwaves do not pass directly through tissues at any significant density, although they do penetrate deeper than infrared radiation. As a result, the effects are more profound than those of infrared radiation, but short-wave diathermy is a better option for treating deeply positioned structures. The water content of the tissues that microwaves must pass through affects how far down they can effectively penetrate, which seems to be around 3 cm. One part of the body can only be exposed to radiation at a time using commonly accessible equipment.Because water absorbs microwaves very well, tissues with good blood flow, like muscle, warm up significantly while tissues with little fluid content, like fat, warm up less. As a result, the condenser field method's short-wave diathermy avoids heating the subcutaneous fat, which is a drawback. The physiological consequences of microwave diathermy's localized temperature increase.

The benefits of microwave therapy

Microwave diathermy can be used to treat the same conditions as short-wave diathermy (a localized increase in temperature), because its physiological effects are similar. These conditions include inflammatory and traumatic lesions, where an increase in muscle spasm can be beneficial, as well as bacterial cells and antibodies. More white blood cells are brought in by the increased blood supply, which strengthens the body's natural defensive system. to the region. Microwave diathermy is a viable therapy option for rheumatic and traumatic disorders affecting the small superficial joints and soft tissues, as it is most likely to be successful for lesions in the superficial tissues and those with high land rheumatoid arthritis. Since it is often possible to irradiate only one part of the body at a time, it is more likely to be suitable for localized treatment than for extensive application. In those situations where both are applicable, microwave diathermy may be preferred over short-wave diathermy.

Perils of microwave-induced diathermy

Burns

Burns from heat can result with microwave diathermy. It is not advisable to employ the procedure if the patient has impaired skin sensitivity, as the patient's sensation serves as the main indicator of the appropriate level of treatment. Although some authorities assert that the skin heats up more than the underlying tissues, if the dose is kept to the recommended levels, injury shouldn't happen. The skin needs to be dry because the waves heat the water quickly. Adhesive tapes and wet dressings should be avoided, and areas that sweat profusely should be treated with caution. Where the emitter is positioned unevenly with respect to the tissues, the concentration of waves could lead to overheating. Similar to short-wave diathermy, it is best to eliminate metal objects from the area.

Eyes

Animal eyes that have been exposed to microwave radiation have developed lens opacities. It is not advisable to treat eye diseases using microwaves, and it is important to avoid irradiating the eyes while receiving other therapies. It is now standard procedure for the patient and the physiotherapist to put on safety goggles composed of wire mesh that can absorb microwaves as a precaution.

Circulatory flaws

Because of the increased oxygen demand brought on by the temperature rise, ischemic areas shouldn't be treated. Patients at Equipment Damage
If the device is left on and the emitter is facing a metal plate that reflects the waves, damage to the magnetron may occur. Although it is unknown how microwaves affect electronic equipment like cardiac pacemakers and hearing aids, it is reasonable to presume that the scenario is similar to that of short-wave diathermy and that microwaves could harm these kinds of gadgets. It is important to be aware of the risk posed by random microwave reflection since the resulting beam pattern may be harmful to patients or therapists. Appropriate technicians should periodically examine the pattern of the microwave beam generated by the emitters in order to spot any potentially dangerous anomalies.

Method of use

Setting up the equipment

After the proper cable has been used to connect the chosen emitter to the machine, the power is turned on. The physiotherapist will test the device by putting her hand or arm in front of the emitter and gradually increasing the output until she feels warmth. There will be a slight delay before output is obtained. After that, the switch is moved to the stand-up position and the controls are reset to zero (the current is cut off if there isn't a stand-by switch).

Patient preparation

This is equivalent to being ready to apply short-wave diathermy. Once the emitter is in place, the patient needs to be advised not to move too much, and complete support in a comfortable position is required to guarantee this. To protect his eyes, the patient is provided with wire mesh goggles.

Utilizing the emitter

The emitter is positioned with careful attention to the surface, with its surface parallel to the skin and at the proper distance. the structure that has to be treated's marking. Avoiding regions that perspire freely and uneven surfaces is advised.

Radiation

The patient is reminded of the expected sensation and the need of honestly reporting what they feel. The output is gradually increased until either the chosen output is unshed or a feeling of warmth is felt, whichever occurs first. The patient receives radiation therapy until the proper point is achieved, with frequent visits from the physiotherapist to make sure nothing unpleasant has happened. After that, the output is decreased and turned off. There might be a slight erythema, but there shouldn't be any noticeable skin reaction.

Quantity

The machine's power output, which can reach 200 watts, can be used to compute the dosage, but the patient's sensation must always be the main factor. In general, weaker doses should be utilized for acute diseases rather than chronic ones, and this should never be more than a comfortable warmth. Irradiation lasts for ten to thirty minutes, with shorter treatments utilized for acute conditions and tiny areas. It is best to start slowly and, in every situation, gradually increase exposure based on the patient's response. Treatment might be administered every day or every other day.

Pads for electric heating

Commercial electric pads come in a range of sizes. Their construction allows for the regulation of a heating element's temperature to the desired level with the use of a number of resistors. Conduction heats the tissues, producing only a surface effect, yet the patient finds this approach simple and comfortable. Precautions that apply to all heat therapy methods also apply when using electric heating pads.

Paraffin Gloss

There are numerous size and shape options for wax baths. Thermostatic control is crucial since the melted wax must be kept between 40° and 44°C for therapeutic purposes. Prior to administering treatment, the wax's temperature needs to be verified. The most practical technique to provide conducted heat to the extremities is by this method of heating the tissue. Wax releases latent heat energy when it solidifies from its molten form, and the tissues absorb this heat energy.

Technique

There should be no wounds, rashes, or infections on the area that has to be treated. The patient should be positioned in accordance with the area that has to be waxed and the kind of wax bath that has been chosen. They should be told to dip the area in and out of the bath repeatedly until a thick layer of wax forms on the skin. Usually, four to six immersions are needed for this. Because wax has a low thermal conductivity, it releases heat slowly; yet, once removed from the bath, the portion cools rapidly. Cover the area with a towel and a layer of plastic sheet or greaseproof paper to keep the heat in. Typically, a treatment session lasts for 20 minutes. Afterwards, remove the wax glove and the cloth, being careful not to spill any wax on the floor. Check the component and let it dry. At the conclusion of the day, the wasted wax is eventually remelted, strained, and added back to the bath.

Results and indicators

The temperature of the skin and, to a lesser extent, the other surface tissues rises noticeably after wax application. Clearly, the temperature reduces quickly after the 20 minutes of treatment.

Impacts on the nerves that sense touch

The sensory nerve endings seem to be sedatively affected by mild warmth. Wax is useful in treating rheumatoid arthritis or "degenerative" joint illness because it can be sculpted to fit the curves of the hands and feet, relieving pain and spasms in the muscles.

Impact on the skin

After applying wax, the skin is hydrated and malleable, which can aid in softening scars and adhesions before mobilizing and stretching the skin.

Restrictions
(a) visible wounds.
(b) rash from allergies.
(c) ailments of the skin.
(d) a malfunctioning arterial blood supply, which encompasses varicose veins and deep vein thrombosis.
(e) reduced feeling of the skin.