|
|
|
|
We are all familiar with the most common uses of microwave energy, that of defrosting and heating food and beverages for consumption. However microwaves have many other applications, in this article we look at the use of microwaves in medicine. In a controlled environment microwaves can travel through the body, or be used to heat a selected area of the human body.
Over the last 60 years forms of energy have been applied to the human body in order to better diagnose and treat a range of illnesses. Extensive research has been carried out in the filed of external heat treatment for tumours, but other areas have been and still are under investigation. Most applications under research are non invasive, or minimally so. More general surgical applications may involve haemorrhagic shock therapy and forms of dialysis for those suffering from kidney disease. Heat is of course already used in medicine such as to cauterise wounds and destroy abnormal cells which may form a harmless protrusion or a tumour. A boom in research in this area in the 1940s lead to many new ideas and ways to utilise microwaves.
The human body naturally emits microwaves in the infra red spectrum. In the presence of disease and or injury the frequency of these microwaves changes. The more severe the patient's condition the greater variation in microwave frequency to that of the individual prior to the onset of the problem. Diagnostic equipment is available that detects and reads these microwaves, aiding diagnoses.
A higher than normal microwave reading from the body may indicate hypothermia, rheumatoid arthritis, prostate cancer, lymphomas, melanomas, carcinomas, fractures, hypermetabolism and other conditions. Tumours such as the aforementioned are detected via changes in the tissue electrical properties. Conditions resulting in an increase microwave frequencies usually involve the patient being in discomfort and pain.
A lower than normal reading may indicate ulceration, neuropathy, atrophy, localised vasoconstriction among other conditions. Some patients may exhibit high and low readings at the same time such as an individual suffering from a range of muscular problems. Nerve energy levels and circulation both affect readings.
Microwave signals can also be used to record the measurements of the heart, and research suggests they may be used increasingly to treat heart rhythm problems via localised dielectric heating (diathermy). By heating abnormal areas of the heart it is thought that abnormal rhythms may be blocked and are not conducted. Heart rhythm problems may be treated with low frequency ablation which destroys selected areas of the heart tissue by heating them, destroying the extra electrical connection often associated with arrhythmias. This low frequency ablation can produce very high temperatures and cause lesions which may progress to become blood clots with the potential to cause serious side effects such as stroke.
Research is on going into the full extent in which microwaves can be used in medicine, most recently the idea of using low level microwave energy to treat malaria. Parasites can be extremely resilient, however none yet have developed a defence against microwaves. The unpleasant but effective theory is that the microwaves heat up the iron rich, digested blood within the parasite. The parasite carries an extra iron atom, which selectively absorbs the microwave energy killing the parasite but leaving normal blood cells unharmed. The idea is to eventually create a human-sized pod in which to carry out the procedure and rid the patient of malaria.
|
|
