PET Scan Works
A Positron Emission Tomography (PET) scanner is the topmost gaining technique that uses a radiopharmaceutical or a radioactive chemical known as the radioactive tracers, it utilizes in the body that will allow to perform scan and understand the functional study inside of the body.
The patient who is about to have a brain scan for example, using the latest PET imaging technology the doctors will be able to see the patient’s brain how it works. It’s all possible because of the tiny tracers an especially designed radioactive molecules. The PET scanner attracts the position of the tracers inside the brain, revealing the brain function in 3 dimensions images. The tracers doesn’t come from the stock room shelves, but each one have to be made fresh at the nearby laboratory.
How tracers are made to detect cancer?
Doctor in Nuclear Medicine is the one who is making these tracers for the PET scan exam, first he need to produce the radioactivity, using a device called the cyclotron. The cyclotron smashes high speed particle into ordinary atoms, transforming them into a new radioactive atoms. As the clock is ticking the new atoms is giving off the radioactivity and becoming a plane radioactive atom again. It means that Radiologist and his team had to work quickly to build the tracer a biological molecule.
This is what makes pet so unique because the molecule could be anything like a sugar, a protein or hormone. Each one is tailored to a specific function in the body and it shows radiologist where in the body is that function is happening. Radiologist and its team run a special chemical reactions to create a tracer from a drug used in the brain. The new tracer must pass the quality control, it is purified and checked that it will function properly.
After the Quality check. The precious custom made molecule is rush to the PET clinic, just the right level of radioactivity is measured out, then it is injected into the patient’s bloodstream. It won’t take too long before patients brain is absorb the tracers, and the clever chemistry gets to work.
How tracers and PET scanner produce an image?
Inside the patients body an incredible reaction is taking place. The radioactive atom on the tracer loses its radioactivity, giving off a sub atomic particles called positron. It’s just like a tiny negatively charge electron found on an old atoms except that the positron is negatively charged. So when the positron hits an electron at just the right speed they combine and destroy each other, the energy is released as 2 gamma rays that travels straight out from the patient’s body in an opposite direction. The PET scanner is like a big ring like of geiger counter.
When it is detected the two gamma rays on opposite side of the ring, the doctors can calculate where in the patient’s body the tracer must be. By detecting thousand of this event every seconds and with some clever of computer processing, the patient’s brain is revealed in 3 dimensional images and something no other imaging technique can do.
