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Sibley Memorial Hospital

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What to Expect

ct scan

Here’s what to expect if your physician requests a PET or CT scan for you.


  • Avoid strenuous activities on the day before and day of your PET/CT exam. Excessive muscular activity may interfere with the interpretation of your exam.
  • Do not eat or drink for six hours before your procedure, with the exception of water.
  • You may need to take medications. Please refrain from chewing gum, as it may interfere with the results.
  • Wear comfortable clothes that are free of metal zippers, snaps, etc.
  • If you are a diabetic, please bring your medication. Make sure our staff is aware of your condition ahead of time. If you take insulin to control your diabetes, you will be scheduled for an early morning appointment, due to the fact that you will not be able to take your insulin on the morning of your exam.
  • Remove all jewelry, hair pins and clips prior to your exam.
  • You may invite a companion to stay with you during the 45 minute “quiet time” before the procedure.

Arriving at Sibley

  • Come to the radiology reception area located on the ground floor of the hospital.
  • Plan to arrive a little early.
  • Change in the private area reserved for PET/CT and MRI patients.
  • You will have a catheter placed into a vein in your arm for ease of injection.
  • We will be injecting you with a small amount of a radiopharmaceutical through this IV line.
  • You will wait quietly in a private room for 45 minutes. It is important that you relax and rest during this time to allow the radiopharmaceutical to properly distribute throughout your body. A companion may wait with you.
  • You will then proceed with scan, which will take approximately 60 minutes.

After the Scan

  • You may leave as soon as the scan is complete. Unless you’ve received special instructions you can eat and drink immediately. Increasing your fluid intake soon after the exam will assist in removing any residual radiopharmaceutical in your system. The radiopharmaceuticals used during your scan do not remain in your system long, so there’s no reason to avoid interacting with others. However, we advise that you wait for a few hours before getting too close to an infant or anyone who is pregnant.
  • Results will be sent to your ordering physician.
  • The entire process — from arrival to discharge — takes approximately three hours.
  • You are encouraged to preregister at the time you make your appointment and to check with your insurance company about coverage and approval in advance.

PLEASE NOTE: The radiopharmaceutical used, FDG, has to be prepared specifically for you the day of your PET/CT. If you cannot make your scheduled appointment, please notify us at least 24 hours in advance; otherwise, you will be charged a fee of $300.00 for the cost of the radiopharmaceutical.

Contact Us

To schedule an appointment, please call 202-537-4795.

For questions, please call 202-243-5164.