Positron emission tomography (PET) is a highly specialized imaging technique that uses short-lived radioactive substances to produce three-dimensional colored images of those substances functioning within the body. These images are called PET scans and the technique is termed PET scanning.
PET scanning provides information about the body's chemistry not available through other procedures. Unlike CT (computerized tomography) or MRI (magnetic resonance imaging), techniques that look at anatomy or body form, PET studies metabolic activity or body function. PET has been used primarily in cardiology, neurology, and oncology.
One of the greatest benefits of PET technology is its use in treating neurological disorders such as epilepsy, Alzheimer’s disease, and other dimentias. Additionally, PET scanning is able to produce images for a number of diseases that affect the brain such as post-traumatic brain injury, brain tumors, and movement disorders.
The brain PET scan is a safe imaging procedure that has a number of benefits over other forms of medical imaging. Anatomical imaging procedures like x-rays, computed tomography (CT), and magnetic resonance imaging (MRI) are useful tools that measure changes in body structure. However, they are limited in their use for a number of diseases, particularly in diseases that affect the brain. Positron Emission Technology, however, is a unique metabolic imaging tool that is based on molecular biology. The images that PET scanning is able to produce detail biochemical changes in the body’s tissues, as it traces the body’s metabolic activity, and is a useful tool for physicians attempting to pinpoint and evaluate diseases of the brain. In many instances, PET imaging is able to detect metabolic changes in the brain before anatomical or structural changes occur.
Still used in medical research, brain PET imaging is an exciting medical innovation that has a number of valuable clinical uses. Brain PET can help:
- Assist surgery for individuals with uncontrollable seizures by locally the brain site of seizure activity.
- Analyze muscle tremor and evaluate whether it this is caused by Parkinson’s disease or some other movement disorder.
- Evaluate brain tumors and determine whether they are benign (alive tissue and non-cancerous) or malignant (dead tissue and cancerous).
- Pinpoint the source of epileptic seizures.
- Assess such medical conditions as degenerative brain diseases, movement disorders, and dementias.
- Assist surgical operations by identifying the areas of the brain responsible for such critical functions as movement and speech.
- Analyze the effectiveness of chemotherapy by examining cites of possible cancer recurrence and distinguishing whether this structural change is due to tumor re-growth or is a form of scar tissue.
Brain PET imaging involves the administration of a radioactive tracer that is a combination of a radioisotope (a radioactive compound whose movements are detectable by a PET scanner) with a natural body compound. When used in brain scanning, the radioactive tracer used in PET is Fluorodeoxyglucose (FDG), which combines the natural body compound glucose with the radioisotope Fluorine-18. This radioactive tracer, or radiopharmaceutical, is used in brain PET imaging as the radioactive compound that it uses has a short half-life that will disappear from the body within hours. Although it is reasonable for individuals to be concerned about the radiation used in PET imaging, this procedure has been shown to be highly safe. Consequently, patients should free themselves of any worry about the radiation content of this procedure.
Brain PET scanning uses FDG as its radioactive tracer because it contains the body compound glucose. The use of FDG, which shares a similar structure to glucose, is important, as brain cells use glucose as their fuel. Consequently, through brain PET imaging, a physician will be able to easily identify brain activity. In cases where there is high brain activity, large amounts of FDG will be consumed. In instances where there is less active brain activity, there will be less absorption of FDG. By identifying brain activity, brain PET scan is useful in the treatment of a number of diseases affecting the brain.
This procedure is available at our main Sarasota campus only.
Learn more about Positron Emission Tomography (PET)
