MICROWAVE DIATHERMY AND SURGICAL DIATHERMY DIATHERMICS

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Monica Chase
5 years ago
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1 MICROWAVE DIATHERMY AND SURGICAL DIATHERMY 1

2 Microwave diathermy Microwave diathermy uses microwaves to generate heat in the body. It can be used to evenly warm deep tissues without heating the skin. Microwave diathermy uses radiation of very high frequency & short wavelength similar to radar waves. All physiologic responses are due to its heating effect. Microwave diathermy is used in the management of superficial tumours with conventional RT & CT. 2

3 Properties of Microwaves Microwave diathermy (MWD), is a form of electromagnetic radiations lying between shortwave and infrared waves. Microwave diathermy does not penetrate as deep as shortwave diathermy. The energy is first absorbed at the surface of the body (skin) and a part of it penetrate and absorbed in deep tissues. It generates Strong Electrical Field and relatively Little Magnetic Field 3

4 Frequency and wavelength Microwave has a much higher frequency and a shorter wavelength than shortwave diathermy. The general frequency of microwave is between 300 MHz to 300 GHz with wave length of 10 mm to 1 meter. The therapeutic microwave generators used frequency of 2450MHz with wave length of 122.5mm. 4

5 Microwave Diathermy Unit A= Power Switch B=Timer C=Output Meter (indicates relative output in watts D= Power Output Level Knob E= Amber Light-Warming up / Red Light- Ready 5

6 MWD Applicators (Electrodes) Circular Shaped Applicators 4 or 6 Maximum Temperature At Periphery Rectangular Shaped Applicators 4.5 x 5 or 5 x 21 Maximum Temperature At Center 6

7 Directors Used in Microwave Applications Circular directors - The heating pattern is more intense around the outer portion than the centre. - There are small and large Rectangular directors The heating pattern tends to be more concentrated in the center of the treated area. 7

8 Production of microwave 8

9 Microwave Production and Device The generator used to produce microwaves has three main components: 1- A multi-cavity magnetron valve 2- A coaxial cable 3- A director. Mechanism of MW production The magnetron produces a high frequency alternating current which is carried by coaxial cable to the transducer (director). The coaxial cable transmits the energy to the director whereas a radiating system comprising an antenna within a reflector that is used to direct the microwave to the patient. 9

10 Microwave Production and Device The alternating current in the antenna produces an electromagnetic field that is directed toward the tissue by a curved reflecting director surrounding the antenna. The presence of a director and the short wavelength of microwave radiation allow this type of diathermy to be focused and applied to small, defined areas. 10

11 Effects of Microwave Diathermy Pain: MWD is useful in the treatment of traumatic and rheumatic conditions affecting superficial muscles, ligaments and small superficial joints. Muscle spasm: which may be reduced directly by MWD or may be reduced by relieving of pain. Inflammation: MWD reduces inflammation by increase blood supply that will increase venous return from the inflamed area and aids the reabsorption of edema exudates. 11

12 Effects of Microwave Diathermy Delayed healing: MWD promotes healing of open skin by increase cutaneous circulation. Infection: MWD can control the chronic infection by increasing the circulation. Fibrosis: The heating effect of MWD increase the extensibility of fibrous tissues such as tendons, joint capsules and scars. 12

Metal implants. Pacemaker. Over growing bone. Hemorrhage. Impaired thermal sensation.

13 Contra-indications Over malignant tissues (tumor). Over ischemic tissues(shortage of oxygen). Over wet dressings and adhesive tapes. Metal implants. Pacemaker. Over growing bone. Hemorrhage. Impaired thermal sensation. Recent radiotherapy. Hypersensitivity to heat. Acute infection or inflammation. Pregnancy Severe cardiac conditions. 13

14 Precautions & Dangers The same as SWD, but it is recommended to avoid the presence of metal within the treatment field (4 feet) because of scattering and reflection of MWD Due to scattering and reflection of MWD to the surrounding environment, it has been associated with high incidence of miscarriages among female therapists who regularly operate these units than SWD. The eyes: MWD may cause cataract. Obesity Burn 14

15 Dosage of MWD Duration of treatment: 20 minutes is the optimum. Intensity: the patient should feel mild and comfortable warmth. Frequency: daily or on alternating day. 15

16 Microwave Device 16

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18 SURGICAL DIATHERMY Surgical diathermy is usually better known as "electrosurgery". (It is also referred to occasionally as "electrocautery ) Electrosurgery and surgical diathermy involve the use of high frequency A.C. electrical current in surgery. 18

19 Principle Surgical diathermy Electro surgery is the application of a high-frequency electric current to biological tissue as a means to cut, coagulate, desiccate(remove the moisture from), or fulgurate tissue. Electrosurgical devices are frequently used during surgical operations helping to prevent blood loss in hospital operating rooms or in out patient procedures. 19

20 Principle of surgical diathermy 20

21 Types of electrosurgical technique Electro-surgical coagulation Fulguration Desiccation Electrotomy 21

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23 Types of ESU Monopolar technique Bipolar technique 23

24 Mono-Polar Technique (flow of current) Active Electrode tip Patient Neural Electrode Generator 24

25 Mono-polar Technique 25

26 Bipolar Technique 26

27 Types of electrodes for cutting Needle electrode Angulated lancet electrode Angulated band loop electrode Wire loop electrode Straight lancet electrode 27

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29 Modes The device has several modes: Cut mode Pure sine wave, for cutting with the least coagulation. Coag mode Pulsed sine wave, lowduty cycle, for coagulating bleeding tissue. Blend 1 mode Modulated sine wave, for coagulating as the tissue is cut. Blend 2 mode Modulated sine wave, for coagulating as the tissue is cut. 29

30 Safety aspects in electro surgical unit i. Burns ii. High frequency current iii. Explosion hazards 30

31 Staff safety Avoid contact with the neutral electrode When applying current, always be sure to wear gloves and touch the equipment or patient body with the entire palm of the hand, not with a single finger. Electrosurgical equipment needs to be grounded in order to minimize interference with video endoscopic systems. Smoke generated during electrosurgical procedures can be irritating and potentially harmful to personnel. surgical masks and adequate ventilation of smoke may be useful 31

32 Advantages over other techniques The sepration of tissue by electric current always take place immediately in the front of the cutting edge It does not require any application force. Instead it facilitates elegant and effortless surgery Preventing contamination of bacteria Bleeding can be arrested immediately during the surgery 32

33 RISKS ASSOCIATED WITH DIATHERMY Diathermy should be avoided in following cases: implanted metal devices peripheral vascular disease tissue with restricted blood supply (ischemia) cancer bleeding disorders, wound dressings severe heart, liver, or kidney conditions pregnancy 33

C14 M 3.3 Diathermy Role Name Affiliation Principal Investigator Dr. Asis Goswami Ramakrishna Mission Vivekananda University Co-Principal Investigator

C14 M 3.3 Diathermy Role Name Affiliation Principal Investigator Dr. Asis Goswami Ramakrishna Mission Vivekananda University Co-Principal Investigator Dr. P.K. Nag Ramakrishna Mission Vivekananda University