Positron Emission Technology

[theblackalchemist]

Positron Emission Technology (PET)

PET is an imaging technique enabling doctors to observe metabolic activities in a specimen ( mostly human bodies ) following a progress of a radioactive chemical ( any idea what is it ? ) that has been inhaled or injected by detecting the gamma radiation which is emitted out by the positrons emmited by the chemical are obliterated

 

correct me if i am wrong positrons are tiny subatomic particles positively charged having the same mass of an electron

 

also any idea how is a PET test done ??

 

thanks

TBA

[ronthepon]

an example of the radioactive chemical used is glucose.

 

They'll give you a glucose solution, and give some time. Then, after the glucose has been distributed throughout the body, they detect the emmision of gamma rays. Where there's more emmision, there's more glucose, and hence more activity.

 

Inactive tissues like post stroke-brain reigons do not get the radioactive glucose, and hence no gamma ray emmision is detected there.

[hallenrm]

First of all let me correct you a bit, it is not Positron Emmision Technplogy, is is Positron Emission Tomography, if you really want to know how it is done, you may start with an article on yhis subject on the Wikipedia (if following the link provided below.

 

http://en.wikipedia.org/wiki/Positron_emission_tomography

[CraigD]

an example of the radioactive chemical used [in PET] is glucose.

This is a slight oversimplification. The most common of the several molecule used in PET is fluorodeoxyglucose (FDG).

 

The practical business of FDG is interesting. In the 1980s, I had an office in a medium-size (300 bed) that shared a wall with room containing a small cyclotron – unusual for a hospital of that size. When it ran, its sweeping magnetic field made my CRT completely unreadable. As a courtesy, the techs gave me a dosimeter badge, which I stuck to my CRT, figuring if something broke or spilled, I’d be more likely to notice the badge going black if it was in front of me than pinned to my shirt.

 

The radiology center for the org were I work now is in a small building in the Washington DC suburbs. It gets its FDG from a lab a couple dozen miles away, and must use it the same day it’s irradiated.

[Fatstep]

In addition to what Craig said, PETs are used most of the time to view the body in action, and it is the device they used to actually diagnose Alzheimer's and Parkinson's disease.