A Positron Emission Tomography (PET) scan is an advanced diagnostic imaging procedure that provides functional images of your body’s organs and tissues. This is achieved by injecting a small amount of a radioactive compound, known as a radiotracer, into your bloodstream before the scan begins. The tracer highlights areas of metabolic activity, allowing physicians to detect disease or monitor the effectiveness of treatment. While the procedure itself is non-invasive and quick, the most common questions afterward center on safely managing the temporary presence of the tracer and understanding the next steps for receiving your results.
Managing Radiotracer and Exposure Safety
The primary radiotracer used in most PET scans is Fluorodeoxyglucose F-18 (F-18 FDG), a substance that mimics glucose. This compound contains a small amount of radioactivity, which means brief, temporary precautions are recommended immediately following the scan to minimize exposure to others.
The radioactive material naturally decays quickly; F-18 FDG has a physical half-life of approximately 110 minutes. To help your body eliminate the tracer even faster, you should focus on increasing your fluid intake for several hours after leaving the facility. Drinking plenty of water or other liquids aids in flushing the remaining radiotracer from your system through the urinary tract.
Frequent urination is encouraged to clear the tracer, and you should use the restroom as often as necessary. Some facilities suggest flushing the toilet twice after use and washing your hands thoroughly to ensure no residual tracer remains. If you are going home to a household with infants, young children, or pregnant women, you must take extra care to limit close contact.
You should avoid prolonged, close physical contact with these vulnerable groups for the first six to twelve hours post-scan. This precaution is advised because their developing bodies are more sensitive to even minimal radiation exposure. While you can generally carry out routine activities, maintaining a distance of about six feet from these individuals is recommended.
Returning to Normal Activities
Once you have followed the initial safety instructions regarding the radiotracer, you can generally transition back to your normal daily routine. Most patients feel perfectly fine immediately after the scan, as the injection of the tracer rarely causes side effects or grogginess. You may immediately resume your normal diet and eating habits unless you were given specific, differing instructions by your medical team.
For most standard PET procedures, patients are not given sedation, which means that driving yourself home is usually permitted. If you were given a mild sedative during the scan, you must not drive or operate heavy machinery for the next 24 hours. In that scenario, arranging for a ride home beforehand is a requirement.
It is generally advised to avoid engaging in strenuous physical activities for the remainder of the day. Intense muscle activity can cause the remaining F-18 FDG to concentrate in those muscles, which can sometimes interfere with the quality of the images. Taking it easy for the rest of the afternoon also allows your body to recover from the procedure.
You may notice slight soreness or a small bruise at the injection site. If you experience any unusual symptoms or feel unwell, you should contact the imaging facility or your ordering physician immediately. For the vast majority of patients, the return to normal activities is seamless and immediate.
Timeline for Receiving Results and Follow-Up
The period following a scan, while waiting for the results, can often be a time of heightened anxiety. Understanding the process and expected timeline can help manage this waiting period effectively. After your scan is complete, the images are sent to a specialist, typically a radiologist or a nuclear medicine physician, who is trained to interpret the highly detailed metabolic information captured by the PET scanner.
This specialist analyzes the images, compares them to any previous scans, and then compiles a report. This interpretation process can take time, usually between 24 hours and five business days, depending on the complexity of the scan and the facility’s workload. The final, official report is then electronically transmitted directly to the doctor who originally ordered the procedure.
The imaging facility staff, including the technologists, are not permitted to discuss or interpret your results with you at the time of the scan. Your ordering physician is responsible for reviewing the report in the context of your overall medical history. They will explain the findings and discuss the implications for your treatment plan.
Because the imaging center sends the results to your doctor, you should direct any administrative questions about the report’s delivery status to your ordering physician’s office. If you do not already have a follow-up appointment scheduled to discuss the PET scan results, you should contact your doctor’s office promptly to set one up. Having a set time to review the findings helps ensure the timely progression of your medical care.