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Medical Cyclotron
Reina A. Jimenez V Policlínica Metropolitana, Venezuela
1. Introduction In this chapter we intend to illustrate the reader about the use of Cyclotrons to produce easy handle radioisotopes, to be used for medical diagnostics or therapies in Nuclear Medicine. Firstofall, we will describe different activation processes to generate artificial radioisotopes, characteristics needed to be safely used in medicine, such as the relationship between fathers and daughters that can compromise patient or environment health. It also will be describe radioisotopes desire behavior inside human body in order to clarify which isotopes can be activated or not in a cyclotron facility to be used in human medical applications. Nuclear Medicine radioisotopes must fulfill four main characteristics in order to be easy handle by operators and be easily and quickly disposed by patients and not to represent environmental radioactive contamination harm, so they have to have: 1. Low activity 2. Low energy 3. Short half life 4. Decay to a stable daughter In Nuclear Medicine, equipment also has to have a high sensitivity to small amounts of radiation and to different types of radioisotopes. The ideal radioisotopes must be easily eliminated by the patient just after the study has been done in a short period of time which is a function of the physical half life of the isotope and the patient excretion system. The total time elapse for patient elimination of any trace of radioisotope used for study is known as Effective Half Life Time and is related to the time isotope population is reduced to its half due to the radioactive decay of father to daughter (Physical Half Life) and the time T / patient systems needs to eliminated of isotope from it system (Biological Half Life) in T / this way: /