Microwave is ultrahigh frequency electromagnetic wave:
Its wavelength is between ultrahigh frequency radio wave and infrared lightwave,and the commenly used frequencies in medical treatment are 433 MHz、915 MHz、2450 MHz.
Microwave has certain penetrance to human body and can cause thermal and non-thermal effects.Using different radiators to control microwave power and time different curative effect can be achieved.
Microwave medical treatment mainly has three different application:
1.Physiotherapy
Using irradiance radiator to do local irradiation of big areas it causes certain osmosis.Local human body absorbs the microwave power and generate gentle haet effect which achieves the purpose of tendon relaxtion and activeation of blood circulation、dephlogisticate.There is no strict temperature rising which is generally 2-3℃.Its feature is that there is no need to take off cloth when doing extraorgan treatment.It can also does inserting physiotherapy,such as anus、vagina etc.
2.Tumor thermotherapy
Domestic and foreign clinic proves that when local tumor accepts 42-43℃thermotherapy assisted with radiotherapy or chemotherapy, curative effect can be greatly improved because of unusual (non-thermal) effect. Thermotherapy usually adopts outer lighting or inserting style radiator and needs to control temperature.Nowadays it develops rapidly and has good effect.Recently,through 915MHz thermotherapy and Co-60 radiotherapy, effective ratio(most tumor disappears ) upgrades from 50%(just radiotherapy) to 80% and it could lower the radiotherapy power as well.
3.tissue coagulation therapy
The general use of touching or inserting radiator lets microwave to generate high temperature(≥100℃) at very small parts of human body, which makes bleeding part cogulate and dry, polypi vaporize, obstruction dredge and tumor be necrosis etc.So it is widely used in digestive medical department、dermatology、department of gynecology、tumor operation etc.
It is proved by clinic to be safer and more convenient than laser therapy, For example,when using endoscope microwave therapeutic instrument to cure gastrorrhagia and gastric polyp,the effective rate approachs 98%.
Other application of microwave treatment:
1.medical linear accelerator 2.TCM microwave acupuncture
3.microwave imaging(tumor diagnosis)
4 disinfection、sterilization、thawing
The thermal effect of microwav
Thermal effect is generated by the strenuous exercise and mutual friction of charged particles and polarized moleculars under the effect of microwave field and can lead to the instant solidification of tissue.It has characteristics of no carbonization、no smoke、no abnormal taste、small damage、strong hemostatic function etc.
Meanwhile thermal effect can generate antiinflammatory and detumescence effects by means of dilating vessels of local tissue、accelerating blood circulation and tissue metabolism、strengthening leukocyte phagocytic phagocytosis、promoting absorption of local pathological metabolites. Hyperthermic effect can lead to pain relief by rescinding muscle spasm and scavenging accumulated lactic acid.
The non-thermal effect of microwave
Non-thermal effect means that when treating with microwave its heat quantity is so small that man can hardly feel it.Then it can generate physiological and therapeutic effects.In fact, local tissues can lead to temperature rising phenomena which can just be detected by precise temperature measuring instrument. Non-thermal effect has reliable curative effect in dephlogisticate and detumescence aspects.The progressiveness of microwave technology will make up the deficiency of electric cauterization、freezing、laser technology and the microwave technology has a fusion with multidisciplinary technology and will enlarge its application range all the time.