Positron Emission Tomography (PET) scans are powerful diagnostic tools that utilize radioactive materials to visualize and assess the function of your body’s tissues and organs. Unlike X-rays, CT scans, or MRI scans that primarily show structure, a PET scan reveals how your body is working at a cellular level. If your doctor has recommended a PET scan, understanding what to expect, especially regarding the duration, can help alleviate anxiety and prepare you for the procedure. A common question many patients have is: How Long Is A Pet Scan Take? Let’s delve into the details to provide a comprehensive answer.
Understanding PET Scans
What is a PET Scan?
A PET scan is an advanced imaging technique used to diagnose, monitor, and manage a wide range of medical conditions. It’s particularly valuable in detecting conditions like cancers, heart problems, and brain disorders. By using a radioactive tracer, a PET scan can highlight areas of increased or decreased metabolic activity, which can be indicative of disease. For instance, rapidly growing cancer cells often exhibit higher metabolic activity and thus appear as “hot spots” on a PET scan.
How PET Scans Work
The magic behind PET scans lies in radiopharmaceuticals, also known as tracers. The most common tracer is FluoroDeoxyglucose (FDG), a glucose analogue attached to a radioactive atom. This tracer is administered to the patient, usually via injection. Because active cells, such as cancer cells or those in inflamed tissues, consume more glucose for energy, they absorb more of the FDG tracer.
The PET scanner then detects the energy emitted by the tracer within your body. This data is processed by a computer to create detailed 3D images that show the distribution of the tracer. Areas with high concentrations of the tracer appear brighter on the scan, indicating higher metabolic activity. Conversely, areas with less tracer uptake might suggest lower activity or potential problems like reduced blood flow.
PET Scan Procedure: Step-by-Step
To accurately answer “how long is a pet scan take,” it’s essential to break down the entire process, from preparation to completion.
Preparation Before Your PET Scan
The total time you’ll spend at the PET imaging department will typically be longer than the scan itself. You should expect to be at the facility for approximately 2 to 3 hours. Prior to the scan, certain preparations are necessary to ensure accurate results. These may include:
- Fasting: Usually, you will be asked to fast for several hours (typically 4-6 hours) before the scan, as food intake can affect glucose metabolism and tracer uptake.
- Hydration: Drinking plenty of water before the scan is often recommended to help with tracer distribution and excretion.
- Medication Disclosure: Inform your doctor about all medications and supplements you are taking, as some might need to be temporarily discontinued.
- Blood Sugar Check: Upon arrival, your blood sugar levels will likely be checked, especially if you are undergoing an FDG-PET scan, as high blood sugar can interfere with the scan’s accuracy.
During the PET Scan
Once you are ready for the scan:
- IV Line Insertion: A healthcare professional will insert an intravenous (IV) line into a vein in your arm or hand.
- Tracer Injection: The radioactive tracer is injected through the IV line.
- Waiting Period (Uptake Phase): After the injection, you will need to rest quietly for about 60 to 90 minutes. This waiting period, sometimes called the uptake phase, allows the tracer to circulate through your body and be absorbed by the tissues. You might be asked to sit or lie down comfortably and avoid moving or talking excessively.
- Bladder Emptying: You will be asked to empty your bladder just before the scan begins.
- Scanning: You will then be positioned on a flat bed that slides into the PET scanner, a large, donut-shaped machine. It’s crucial to remain as still as possible during the scanning process to ensure clear images. The actual scan time itself is relatively short, usually lasting between 15 to 30 minutes. For some specific scans or combined PET/CT scans, it might take slightly longer.
After the PET Scan
Following the scan:
- Image Review: The medical staff will review the images to ensure they are of good quality.
- IV Line Removal: The IV line will be removed.
- Hydration Encouragement: You will be advised to drink plenty of fluids to help flush the radioactive tracer out of your system.
- Results: A specialist will analyze the PET scan images and prepare a report for your doctor. Your doctor will then discuss the results with you, usually within a few days.
Duration Breakdown: What to Expect Time-Wise
To summarize the answer to “how long is a pet scan take,” consider these timeframes:
- Total time at the facility: 2 to 3 hours.
- Tracer uptake waiting period: 60 to 90 minutes.
- Actual scan time: 15 to 30 minutes.
It’s important to note that while the scan itself is quick, the preparation and uptake phases contribute to the overall appointment duration.
Factors Affecting PET Scan Duration
While the times provided are typical, several factors can influence the total duration of your PET scan appointment:
- Type of Scan: Some specialized PET scans or combined PET/CT scans might require slightly longer scanning times.
- Area of the Body Being Scanned: Scans covering larger areas may take a bit longer.
- Specific Facility Protocols: Different imaging centers may have slightly varying protocols that could affect the overall time.
- Patient Cooperation: The patient’s ability to remain still during the scan is crucial. Movement can necessitate repeating parts of the scan, potentially adding to the time.
Safety and Considerations
Are PET Scans Safe?
PET scans are generally considered very safe procedures. The amount of radioactive tracer used is minimal, and it is designed to be short-acting, meaning it leaves your body relatively quickly. The radiation exposure from a PET scan is comparable to that of other common radiological procedures and is often similar to the amount of natural background radiation you might receive over a few years.
Allergic reactions to the tracers are rare and typically mild. There are generally no long-term side effects associated with PET scans.
Conclusion
In conclusion, when considering “how long is a pet scan take,” remember that while the scan itself is usually between 15 to 30 minutes, the entire appointment, including preparation and waiting time, can take 2 to 3 hours. Understanding this timeline helps you plan accordingly and feel more at ease on the day of your scan. If you have any concerns or questions about your upcoming PET scan, always consult with your doctor or the imaging center staff. They can provide personalized information based on your specific situation.
For further reliable information about PET scans, you can refer to resources like the Cancer Council and healthdirect.
Resources and support
For more information about PET scans, when they are used and how they are done, see the Cancer Council website.
Call healthdirect on 1800 022 222 at any time to speak to a registered nurse (known as NURSE-ON-CALL in Victoria) for more information and advice.
