Author: Glossary

  • Photoluminescence

    The power of an object to become luminescent when acted on by light.  

  • Photolabile

    The characteristic of being destroyed or inactivated by light.  

  • Photokinetic

    Reacting with motion to stimulation by light.  

  • Photofluorography

    Photographing the images seen during fluoroscopic examination. The procedure involves capturing the radiographic image using a photographic technique. To illustrate, a stream of radiation passes through the chest and impinges upon a dedicated fluoroscopic screen located at the terminus of a light-tight enclosure. At the opposite end, a camera captures the projected fluoroscopic image onto…

  • Photoelectron

    An electron that is ejected from its orbit around the nucleus of an atom by interaction with a photon of energy (light, x-radiation, and so on). The ultimate outcome occurs when a photon, having traversed a body of irradiated matter, comes across a tightly bound electron, specifically the electron residing in closest proximity to the…

  • Photoelectricity

    Electricity formed by the action of light.  

  • Photoelectric effect

    An interaction between x-rays and matter in which the x-ray photon ejects an inner-shell electron, causing a cascade of outer-shell electrons to fill the hole. The changing of energy shells releases secondary radiation equal to the difference in the binding energies. This absorption reaction increases the patient dose and creates contrast on the radiographic film.…

  • Photodynamic

    To the effects of light on biological, chemical, or physical systems.  

  • Panretinal photocoagulation

    The use of high-intensity light or laser to create hundreds of tiny retinal burns outside of the vascular arcades. This treatment has been shown to produce regression of abnormal blood vessels in patients with proliferative retinopathy from diabetes or retinal vein occlusion,  

  • Extracorporeal photochemotherapy

    The exposure of blood that is temporarily removed from the body to ultraviolet A radiation. This is used to treat several diseases, including pemphigus vulgaris and cutaneous T cell lymphoma.