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Leukemia & Lymphoma

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Positron Emission Tomography (PET)

What Affects the Test

Reasons you may not be able to have the test or why the results may not be helpful include:

  • Being pregnant. A PET scan is not usually done during pregnancy because the radiation could harm the unborn baby (fetus).
  • Using caffeine, tobacco, or alcohol in the past 24 hours.
  • Not being able to lie still for the test.
  • Using sedatives.
  • Taking medicines, such as insulin, that change your metabolism.
  • Having recently had surgery, a biopsy, chemotherapy, or radiation therapy.

What To Think About

  • A CT scan and PET scan may be done at the same time.
  • Single photon emission computed tomography (SPECT) imaging is a method that may be used to diagnose a person with symptoms of heart disease. SPECT imaging also may be done to see if a person with coronary artery disease (CAD) is likely to have a heart attack or other serious problem.2


  1. Johnson KA, et al. (2013). Appropriate use criteria for amyloid PET: A report of the Amyloid Imaging Task Force, the Society of Nuclear Medicine and Molecular Imaging, and the Alzheimer's Association. Alzheimer's and Dementia, 9(1): e1-e16.

  2. Hendel RC, et al. (2009). ACCF/ASNC/ACR/AHA/ASE/SCCT/SCMR/SNM 2009 appropriate use criteria for cardiac radionuclide imaging. Circulation, 119(22): e561-e587.

Other Works Consulted

  • Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.

  • Pagana KD, Pagana TJ (2010). Mosby’s Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby.

ByHealthwise Staff
Primary Medical ReviewerAdam Husney, MD - Family Medicine
Specialist Medical ReviewerHoward Schaff, MD - Diagnostic Radiology

Current as ofSeptember 9, 2014

1 | 2 | 3 | 4

WebMD Medical Reference from Healthwise

Last Updated: September 09, 2014
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

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