PET/CT Scan
PET (positron emission tomography) scans provide specific information about organ and cell functioning by distinguishing among healthy, diseased and dead tissue; CT scans provide a detailed picture of the body's internal anatomy. Cedar Park Regional Medical Center's PET/CT scanning technology combines the physiological information from a PET scan and the anatomical information from a CT scan to provide an image of the body in a single scan.
PET/CT imaging is primarily used to diagnose cancer and evaluate treatment by providing:
- Information about cellular activity to help doctors distinguish between benign and malignant tumors.
- A single, full-body scan that reveals where cancer exists.
- Evidence of cellular changes - which can be seen much earlier than structural changes - to allow doctors to evaluate treatments earlier and make necessary modifications.
- More accurate information to detect recurrence. PET/CT scans can provide clear images of tumors that are often obscured by scar tissue (from surgery or radiation) when using other imaging techniques.
Computed tomography (CT) is a type of X-ray machine that uses a computer to obtain detailed images of your body. The CT scanner looks like a large doughnut with a table that extends into the opening of the machine. CTs are used for a variety of tests that can image every part of your body. These scans can help in the diagnosis of infections, cancer, heart disease, fractures and many other conditions. The CT scanner is helpful in guiding physicians during biopsies and other invasive procedures.
What are the risks?
Similar to an X-ray procedure, CT scans use radiation to obtain images of your body. Technologists are trained to use the minimum amount of radiation necessary to obtain the most information possible. If there is a chance you may be pregnant, please inform your physician and CT technologist before getting a CT scan. You and your physician can decide if you should proceed with your scan. It may also be necessary for you to get a pregnancy test before your scan.
CT scans have many benefits that outweigh the risks of the radiation you may receive. Some of those benefits include:
- More detailed results than a standard X-ray.
- Faster, more convenient and less invasive than other methods, such as surgery.
- Able to detect very small abnormalities so treatment can begin sooner, when chances for a cure are greater.
You should talk to your doctor to learn if there are any other benefits or risks specific to your procedure.
What will the exam be like?
A CT scan usually lasts about 10 minutes. You will be lying on a table that is then moved into the machine to obtain your scans. During the scan you will hear a whirring sound, and you may be asked to hold your breath for a short amount of time. It is important to relax and hold still during your scan.
How should I prepare for the exam?
If you are having a CT that requires an injection of iodine, you will need to fast for four hours before your test. Please wear comfortable clothing without any metal fasteners or accessories. There is a possibility you may have to change into a hospital gown. The technologist may ask you to remove jewelry, hearing aids, glasses, hairpins and dentures.
Contrast
Depending on the type of CT exam being performed, you may be asked to drink contrast. This is a liquid that helps the radiologist obtain a better look at your digestive track and internal organs. If it is necessary for you to drink contrast, you will be given oral contrast before your CT exam. You may need to wait 1 hour in order for the contrast to make its way through your digestive tract. This is necessary to obtain the best images.
Some tests may require an injection of iodine, which is another type of contrast. This contrast will be injected into your vein, and enables the physicians to evaluate your internal organs thoroughly. The iodine contrast will give you a warm flushed feeling and you may experience a metallic taste in your mouth. These sensations last for only one or two minutes. If you feel itchy, short of breath or dizzy after your iodine injection, please inform the technologist immediately as you may be developing an allergic reaction to the iodine.
If you are 50 years of age or older or have a history of kidney failure, diabetes or both, it will be necessary for you to have a blood test to determine if your kidneys are functioning well enough to tolerate the iodine injection
How will I learn the results?
A radiologist will study your CT images and report the results to your physician. You will be able to obtain the results of your CT through your healthcare provider.