PET / CT
A PET/CT combines the functional information from a Positron Emission Tomography (PET) exam with the anatomical information from a Computed Tomography (CT) exam into one single image.
A PET scan detects abnormal cell metabolism or how your cells are utilizing nutrients like sugar and oxygen. Many tumors and inflammatory processes have abnormal cell metabolism which shows up on PET scans. A CT scan uses X-rays to give the radiologist a non-invasive way to see inside your body. It is important to note that the CT exam performed as a part of a PET/CT study is limited and usually does not replace a regular CT exam with oral or IV contrast.
The PET scan pinpoints abnormally elevated metabolic activity in cells, and the CT exam provides an anatomical reference for the PET findings. When these two scans are fused together (PET/CT), the exact location of the abnormality can be pinpointed which in turn facilitates treatment.
What will I experience during the test?
The technologist will explain the procedure for your specific exam and answer any questions you may have. The technologist will then take a blood sample to confirm that your blood sugar is at an acceptable level for the exam to work properly.
Once the sugar level is confirmed, and the exam is to continue the technologist will inject and imaging agent called FDG. You will need to rest quietly for approximately 45 minutes to allow the FDG to circulate throughout the body. The technologist will then begin your scan. It is important to remain still during this time to acquire quality images.
Please refer to these instructions when preparing for a scheduled exam.
DAY BEFORE EXAM
PLEASE NOTE: If the instructions are not followed closely, the exam may need to be rescheduled. Contact your doctor or our Central Scheduling department if you have any questions about this prep or your exam.
- Nothing to eat or drink six (6) hours prior to the injection except for water.
- No strenuous exercise 24-48 hours prior to the exam.
- Please bring previous related studies.
- The last meal you consume prior to coming in for your PET/CT exam needs to be a high protein meal (meat, chicken, fish, eggs, and green vegetables), no carbohydrates or sugars (bread, cereal, fried foods, sauces or salad dressings, fruits, juices, or alcohol) with the meal. Water is acceptable.
- No steroids or medications that require food the morning of your exam. You may take these medications after your exam is complete. Medications requiring water only may be taken any time.
Diabetic Patient Prep – A.M. exam only
- Nothing to eat or drink after midnight except for water. You may take your medications with water.
Insulin Dependent Patient
- Take insulin in A.M. with food or water six (6) hours prior to your exam.
Note: Diabetic Patients ONLY – If you feel this prep will not safely allow you to have this exam performed, please call 210.617.9PET (9738) for further instructions.