Medical Dosage Knowledge
The true genius in radiation therapy is the ability to determine how the human body will react and take in the isolated nuclear energy.
“ The absorbed dose of radiation is the energy of ionizing radiation absorbed per kilogram of tissue. The SI unit of absorbed dose is the Gray, abbreviated Gy. It is defined as
1 gray= 1Gy = 1 J/Kg of absorbed energy “
Another Term we need to know in order to start having fun with physics is the Relative Biological Effectiveness (RBE), which is defined as “ the biological effect of a given dose relative to the biological effect of an equal dose of x rays.” We need to know the RBE because though the gray is independent of the actual radiation used, different kinds of radiation have different effects on the body.
Now that we know about absorbed energy (Gy) and RBE lets learn about how they relate together. If we take the ionization radiation (absorbed dose) and multiply it by the ability for the radiation to cause biological damage (RBE) you get the Dose Equivalent. The unites associated with the dose equivalent is the Sievert (Sv). If we put all of this together we realize the power of the dose equivalent, because if a patient receives 1 Sv it is independent of what radiation is used.
Photo from: radiopharmacy.com