Please note that we are seeing high patient volumes in the emergency department. Learn more >>.

Know before you go to the ER
Select the search type
  • Site
  • Web

PET Scans

PET (positron emission tomography) scans are noninvasive diagnostic exams that can detect diseases sooner than could be seen on a CT or MRI scan. Our specialists use PET scans to determine with a high level of accuracy if there is any cancer present, or if a tumor is benign (noncancerous) or malignant (cancerous). We also use this advanced technology during cancer treatment to monitor progress and test for any recurrence of disease.

PET Scans: Why Choose Us?

When you come to the Washington University Mallinckrodt Institute of Radiology at Barnes-Jewish Hospital, you will find:

  • Advanced technology: Our radiologists use the most advanced technology available to perform highly complex cardiac PET imaging and identify and build treatment plans for difficult cancers, like neuroendocrine and prostate.
  • Experienced team: Our radiologists and technologists have advanced levels of training and the experience to spot even the smallest abnormalities, which can lead to earlier diagnoses and more successful treatment. Meet our radiology team.
  • Pioneering treatments: Advances in PET studies have allowed our radiologists to pioneer work in prostate cancer and Alzheimer’s imaging, leading to a more accurate diagnosis and targeted treatments.
  • Respected academic institution: Barnes-Jewish Hospital’s affiliation with Washington University School of Medicine means that we care for a high volume of complex and difficult cases. Our radiologists are able to recognize and treat patients with rare diseases that other hospitals might not be equipped to handle.

PET Scans: What to Expect

Here’s what you can expect when you come in for your PET scan:

  • Receiving the radioactive substance: Before your test, you’ll be given a small dose of radiotracer by injection, swallowing or inhaling a gas. If the radiotracer is injected into your arm, you might feel a cold sensation moving up your arm. If the radiotracer is swallowed, it has little or no taste. If inhaled, you should feel no differently than when breathing normally.
  • Letting it take effect: It can take anywhere from several seconds to several days for the radiotracer to travel through your body and accumulate in the organ or area being studied. As a result, imaging might be done immediately, a few hours later or even several days after you've received the radioactive material. We will discuss this with you when you schedule your test.
  • During the test: A technologist will help you onto the screening table and make sure you’re comfortable. Once the exam begins, you will be asked to remain still until the exam is over. The technologist will be in an adjacent room, but will remain in contact with you through an intercom. You will also be given a call button to talk to the technologist at any time.
  • The equipment used: A PET scanner is a large machine with a round, donut-shaped hole in the middle, similar to a CT or MRI unit. Within this machine are multiple rings of detectors that record the emission (release) of energy from the radiotracer in your body.

Preparing for Your PET Scan Appointment

Before you come in for a PET scan, please follow this checklist:

  • Have these documents with you:
    • A photo ID (driver’s license or state ID)
    • Insurance card(s)
    • A completed Medication Record
  • Medication: Take your medication as you normally do, unless your referring physician has told you otherwise.
  • Food and drink: You should not chew gum 4-6 hours prior to your appointment. You should arrive to your appointment fully hydrated. For exams before 1 p.m., do not eat or drink anything except water after midnight prior to your exam. For exams after 1 p.m., you may have a light breakfast, but do not eat or drink anything except water after 7 a.m.
  • Don’t exercise: Refrain from strenuous physical exercise 24 hours prior to your exam.
  • Be prepared to discuss your medical history: We may ask you about your completed Medication Record, allergies and any previous surgeries. Women should always inform their physician and the PET scan technologist if there is any possibility that they are pregnant.
  • Dress comfortably: Wear comfortable, loose-fitting clothing to your exam. In some cases, we will give you a hospital gown to wear during the procedure.
  • Remove jewelry: Jewelry and other metallic accessories can interfere with the procedure and should be left at home or removed before the exam. You will be given a place to store your items before the procedure.

Contact Us

New patients: To schedule an appointment, please call 314.362.7111 or toll free at 877.992.7111. Please note: You or your referring physician will need to provide a referral order before your appointment.

Current PET scan patients: Please call the PET department at 314.362.8275 with any questions about your PET scan. Get all the patient information you need, including additional contact information and maps to our locations.

Find a doctor or make an appointment: 866.867.3627
General Information: 314.747.3000
One Barnes-Jewish Plaza
St. Louis, MO 63110
© Copyright 1997-2024, Barnes-Jewish Hospital. All Rights Reserved.