
5
Basics of nuclear imaging
In nuclear imaging (NI) in medicine, the electromagnetic radiation is used
to obtain informatio n about various physiological functions. The radiatio n
originates inside the patients and ideally the detectors of NI cameras detect as
many as po ssible of the photons originated for m within the body. The energy
of electromag ne tic radiation used for imaging is large enoug h to penetrate the
tissues. However, if the photon energy is high (for example 2 MeV per photon)
and almos t no attenuation occurs in the body, the detection of such high-
energy radiation is difficult (the matter becomes “transparent”) and hardware
needed