Position emission tomography (PET) identifies pathology based on altered tissue metabolism
The fundamental imaging relies on radioactive molecule (radio tracer) that decays with positron emission .
Method
- The radiotracer (FDG ) is given intravenously to the patient
- FDG taken into cells. And cell recognizes it as being “Foreign”
- Trapped early in its metallic pathway.
(Malignant cells trap more radio-tracer compared c non-malignant cells)
- Position travels a short distance in tissue before colliding c electrons
- Annihilation reaction resulting 2 photons known as gamma rays of 511 Kev.
- The photon are detected by opposing electron
- Computer resemble these signals into images which represent radio active tracer uptake in the part of body scanned.
