In parallel with the development of the diagnosis techniques and cure by X rays, the physicians explore other alternative techniques. The gamma rays chamber, to detect radiation of wave length shorter than the X ray wave length. Artificial radioisotopes, to produce gamma rays, with long mean life. Linear accelerators (or linacs) to produce energetic X rays. And others.
The detection of the gamma rays originated from the disintegration of radioisotopes, specially of those of large mean life. This made the physicians prefer the radioisotopes technique to diagnosticate and to explore the liver and the brain. And the fine tunning of the out coming energy from the linacs, make the physicians substitute the source of cobalt by linacs.
Other technique came along. The ultrasound, Doppler effect techniques, computarized
tomography, nuclear magnetic resonance, the tomography by emission of positrons
(
, or antimatter of the 
), the thermography, the thermotherapy, the chemotherapy,
the Monte Carlo technique, and others that resulted from the combination of two or more
of the above mentioned and of the modern electronics, the modern optics, and of the
modern computation.
Some techniques apparently are not harmful; like the ultrasound technique; other techniques are; like the radiotherapy. Some techniques are very simple; like the radiology; other are complicate and expensive; like the therapies based on radioactive isotopes. In all cases, the computers are present. The physicians use them to do complicate calculations of doses to radiotherapy. To do analysis of images. To automatize the collection of data from the laboratory. Etc.
The laboratory data comprises the production of organ images. The physicists invented the computerized tomography for this end. This technique can perform, through different scans of the interesting organ and sophisticate computational algorithms, tridimensional images. This technique is useful in surgery, for it gives the surgeon the exact localization of malformations, obstructions, anomalous growths, etc. and the oncologist gives images to plan and monitor the treatment.
The magnetic nuclear resonance is another technique that let the physician to plan and to monitor the treatments. It is based on very simple ideas. And in very simple physical concepts. The quality of the images are comparable to those obtained by computarized tomography. It has additionally the advantage of not using the harmful X rays. It uses very intense magnetic fields. Some 8000 times more intense than the terrestrial magnetic field.
The used ideas are very simple. The human body is composed basically by water. Close to
. This is, of hydrogen atoms and oxygen atoms. This is the central idea. The strong
magnetic fields can line up the magnetic moment of nucleus of hydrogen atoms. And when
the magnetic field is imposed and then released, the hydrogen atoms emit
electromagnetic radiation. The physicians produce images detecting and analyzing
that electromagnetic radiation.
The produced images by magnetic nuclear resonance complement that obtained by computarized tomography. Due to the technique of magnetic nuclear resonance produces only plane images; in any plane, combining the two techniques, the physician can obtain a more exact diagnostic and can monitor his therapy. In conjunction with computation and fast electronics, these techniques give very clear tridimensional images of organs, and of very tender structures of the body.
The physicians calculate the amount of energy, required to destroy tumours, via the Monte Carlo technique. Also to calculate the amount of energy deposited in the human body when it is radiated.