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Women's Health

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Thyroid and Parathyroid Ultrasound

What Affects the Test

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

  • Not being able to hold still during the procedure. Movement can interfere with the quality of the ultrasound picture.
  • Having an open wound in the area that needs to be viewed.

What To Think About

  • A radioactive thyroid scan and radioactive iodine uptake (RAIU) test are nuclear medicine tests that use a radioactive substance to see how well the thyroid is working and identify thyroid problems. For more information, see the topic Thyroid Scan.
  • A thyroid ultrasound does not use a radioactive substance; it is easier to perform and is less expensive than a radioactive thyroid scan or RAIU test. But a thyroid ultrasound does not provide information about how well the thyroid gland is working.
  • A thyroid ultrasound may be done at the same time as an RAIU test. RAIU testing is used more often than a thyroid ultrasound to identify problems such as hyperthyroidism. A thyroid ultrasound can be used to identify different types of thyroid problems, especially problems such as thyroid nodules.
  • Thyroid nodules are common, especially in women and older people.
  • Thyroid ultrasound can usually show the difference between a cyst, a solid nodule, or another type of mass that needs further testing. A fluid-filled sac that is smooth and round and that does not have any particles floating in it is likely to be a simple cyst. A lump that does not have any fluid or that has fluid with floating particles needs to be checked more closely. If a solid nodule is found, a thyroid biopsy may be needed.

Other Works Consulted

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

ByHealthwise Staff
Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine
Specialist Medical ReviewerMatthew I. Kim, MD - Endocrinology

Current as ofNovember 14, 2014

1 | 2 | 3

WebMD Medical Reference from Healthwise

Last Updated: November 14, 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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