Positron emission tomography (PET) is a type of image test utilized to show the biochemical or metabolic activity of your organs and tissues. This image test can detect diseases prior to the appearance of these diseases with the use of a radioactive tracer.

In this image test, the radioactive tracer will be injected in a vein along your arm or hand. Then, the tracer will work on pinpointing where your disease is. Furthermore, images from the PET test are often combined with MRI or CT scans. They are then referred to as PET-MRI or PET-CT.

What Is PET Used For?

The Positron emission tomography or (PET)  scan is often used by doctors to diagnose, monitor, or treat certain conditions, such as:

Cancer. PET scans may not only detect cancer, but it may also reveal its severity, monitor whether the treatment for cancer is working, and look for any recurrence or relapses.

Brain Disorders. The PET scan may also be used to assess various disorders in the brain, such as seizures, tumors, and even Alzheimer’s disease.

Heart Diseases. Pet scans may also show which areas of the heart have decreased blood flow. This can greatly help doctors determine the type of illness you have, and which surgery would be best suited for your disease.

What Precautions Must You Take Before A PET Scan?

To guarantee your safety before a PET scan, you must first inform your doctor whether:

  • You are or may be pregnant
  • You’re breastfeeding
  • You have severe allergic reactions
  • You have existing medical conditions or have been recently sick
  • You’re claustrophobic

Moreover, it is also advised to avoid any strenuous exercise for at least two days before your test. Also, fasting for four hours before the PET scan is also required.

What Should You Expect During The Procedure?

A PET-CT scan lasts for around 30 minutes, while a PET-MRI scan for 45 minutes. Also, in order for the images to come out clearly, you will need to stay very still during the scan.

However, you may feel quite anxious during the scan, especially if you have claustrophobia. For this, a drug may be prescribed to help you relax.

What Should You Expect After The Procedure?

Unless the doctor advises otherwise, you can continue with your daily routine after the test. Also, in order to flush out the remaining radioactive tracer in your body, you should drink a lot of fluids.

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