What is PET/CT Scan?
Positron Emission Tomography (PET) and Computerized Tomography (CT) are imaging tools that assist physicians in locating disease within the body in order to make treatment reccomendations.
The PET scan detects the metabolic growth of cancer cells in the body, while the CT scan provides an image of the internal anatomy that reveals the exact location, size, and shape of the cancerous growths.
In other words, malignant tumors are detected with PET and precisely located with CT. Combined, PET/CT is more accurate than PET and CT alone.
How does PET Work?
Cancer cells grow more rapidly than normal cells in the body. Growing cells use glucose as a primary source of energy. The faster the cells grow, the more glucose is consumed.
A form of glucose called FDG, which emits particles called positrons, is injected into the patient. The FDG molecules are consumed more in fast growing cancer cells than in normal cells, resulting in concentrations of the FDG and positrons in areas of concern. A PET scan where positrons are being emitted from within a patient can provide images that pinpoint the locations.
The examination usually takes less than 30 minutes, providing diagnostic information to the physician and medical team very quickly. The PET/CT system provides exceptional image quality and accuracy of diagnostic information.
- Determine the extent of disease
- Determine the location of disease for biopsy, surgery, or treatment planning
- Assess the response to and effectiveness of treatment
- Detect residual or recurrent disease
- Assist in avoiding unnecessary and invasive diagnostic procedures
The benefits of PET/CT (over PET only) are:
- Scan time of 20-30 minutes instead of 1 hour with PET only
- Both scans are completed simultaneously versus two separate scans on two separate tables with a total scan time of up to 1 1/2 hours.
- PET/CT provides earlier detection of recurrence by revealing small tumors that might be obscured by scan tissue from surgery or radiation therapy.
- PET/CT provides the most accurate staging and localization of cancerous growths.
- At least 6 hours before your scan, do not eat or drink (except water). Do not chew gum.
- Your last meal before your scan should be high in protein and low in carbohydrates. For example: Dinner: Steak, baked fish, cheese, asparagus, broccoli, or mushrooms. No pasta, potatoes, rice, or bread. Breakfast: Eggs, bacon, sausage. No breakfast should be eaten if you have an appointment before noon.
- Continue to take any medications prescribed by your physician. If you have been advised to take your medications with food, eat nothing more than a few soda crackers 4-8 hours before your exam.
- Avoid caffeine, sugar, tobacco, and heavy exercise for 24 hours prior to your exam.
- If you have diabetes, discuss this with your physician and call the center staff 48 hours before your exam.
- If you are, or think you might be pregnant, discuss this with your physician. Generally, PET/CT is not performed on pregnant women.
- Please arrive 20 minutes before your scheduled appointment.
- If you must cancel or reschedule your appointment, please do so at least 24 hours in advance.