Radiology - Technology Information Portal
Thursday, 31 October 2024
• Welcome to Radiology-TIP.com!
     • Sign in / Create account
 
 'Annihilation' 
SEARCH   
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 
Searchterm 'Annihilation' found in 3 terms [
] and 4 definitions [
]
Result Pages :
Annihilation
Annihilation in general refers to the transition of a particle and its antiparticle by collision into something different, depending on their energies and based on the conservation of energy and momentum. The electromagnetic radiation emitted is the result of the annihilation (combination and disappearance) of an electron and a positron. Two gamma rays of 0.511 MeV energy, assuming very low-energy particles, are emitted perpendicular to each other.
Electron Positron Annihilation
When an electron collides with its antiparticle, a positron, causing both elements to be completely destroyed and in most cases resulting in the emission of gamma rays.

See also Electron, Positron and Antiparticle.
Annihilation Coincidence Detection
(ACD) Caused by positron decay and positron annihilation two photons are emitted each with an energy of 511 keV in opposite directions. The simultaneous detection of these two photons, by two detectors indicates that a positron annihilation occurred at the line of response (LOR), the path between the two detectors.
In PET imaging the annihilation coincidence detection is used to localize the tracer, e.g. F18.

See also Positron Decay and Electron Positron Annihilation.
Coincidence Detection
Coincidence detection is the simultaneous detection of two signals. The simultaneous detection for example of two photons, annihilation coincidence detection, is used in PET imaging.

See also Annihilation Coincidence Detection.
Cerebral Blood Pool Imaging
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.
Result Pages :
 
Share This Page
Facebook
Twitter
LinkedIn

Look
      Ups
Radiology - Technology Information Portal
Member of SoftWays' Medical Imaging Group - MR-TIP • Radiology-TIP • Medical-Ultrasound-Imaging
Copyright © 2008 - 2024 SoftWays. All rights reserved.
Terms of Use | Privacy Policy | Advertising
 [last update: 2023-11-06 02:01:00]