A critical organ is the body part receiving the highest dose or experiencing the highest risk from radiation exposure.

Cystografin® (USP30% or Cystografin®-Dilute USP 18%) is a radiopaque contrast agent for retrograde cystourethrography. Cystografin® is not intended for intravascular injection.

Decay chain or decay series is a series of decays that certain radioisotopes go through before reaching a stable form. For example, the production of technetium-99m (daughter nuclide with a half-life of 6 hours) from molybdenum-99 (parent nuclide with a half-life of 66 hours) in a generator is part of a decay chain.

See also Decay and Generator.

Despeckle is a process to remove unwanted groups of black pixels from an image.

Diaphanography is a noninvasive breast imaging technique used in diagnosis of breast disease. The breast is illuminated with low intensity light and the transmission pattern of red and near-infrared radiation is detected. After amplification and reconstruction, the images are displayed on a monitor.
Results from diaphanography tend to show lower sensitivities and specificities than are found in diagnostic mammography studies. Light scanning (diaphanography and transillumination) is not recommended for screening or diagnostic evaluation of the breast.