Breast imaging methods include mammography (mammogram), ultrasound, breast MRI, positron emission tomography, xeromammography, diaphanography and thermography.
Mammography is widely used as a screening method and diagnostic tool for breast cancer detection or evaluation of breast disease. Digital mammography takes multiple thin digital image 'slices' through the breast, which provides higher potential to see a small mass within dense tissue. The mammography quality standards act guarantees a high image quality.
Breast ultrasound (also called ultrasonography) should only be used as an additional imaging modality to evaluate specific breast abnormalities, especially to differentiate cystic from solid masses. Ultrasound is also used to guide needle breast biopsies.
Magnetic resonance imaging (MRI) is useful for breast MRI screening in cases of high cancer risk. In addition, multifocal breast cancer can be missed by standard practice mammography and can be early detected with breast MRI.

The cerebral blood pool can be imaged with single photon emission computed tomography (SPECT) and positron emission computer tomography (PET) techniques. The used radiopharmaceuticals are technetium-99m labeled red blood cells (RCBs) for SPECT and O-15 labeled water for PET imaging. Measured can be cerebral blood volume, brain perfusion and cerebral metabolism.

See Cerebral Metabolic Imaging, Fluorodeoxyglucose, Regional Cerebral Blood Flow, Coincidence Detection, Annihilation Coincidence Detection and Cyclotron.

Charged particles (ions) range from lighter electrons and positrons to heavier alpha particle and other not neutral nuclei. The charge is measured in coulomb.

(K-capture) An unstable atom with too many protons in the nucleus, and not enough energy to emit a positron, reaches a stable state in the way, that one proton captured an electron from the atom's inner shell (K-shell) and change to a neutron. A neutrino is emitted from the atoms nucleus by this process. The atomic mass of the atom is unchanged, but the decreased number of protons transformed the atom to a different element.

Gamma rays are a form of nuclear radiation that consists of photons emitted by radioactive elements from the nucleus. This high energetic light emission is also produced from subatomic particle interaction, such as electron positron annihilation. Gamma radiation, similar to x-radiation can injure and destroy tissue, especially cell nuclei.
Gamma rays have in general very high frequencies, short wavelengths, are electrically neutral and penetrate matter. The interaction of gamma rays with matter depends on the nature of the absorber as well as the energy of the gamma rays; these interactions determine also the type and amount of shielding needed for radiation protection.

See also Radiation Safety, Lead Equivalence, Lead Apron, Leaded Glove, Glove-Box, Radioactive Decay Law and Radiation Worker.