Parathyroid MIBI Scan

Authors: Ms Maria Triantafillou*
                            Dr Dee Nandurkar *

What are the prerequisites for having a parathyroid MIBI scan done?

  • Documentation of an elevated serum calcium and parathyroid hormone. Documented increased urinary excretion of calcium is also advised when other laboratory abnormalities are mild.
  • History of prior thyroid or parathyroid surgery should be provided.
  • Results of CT, MRI or ultrasound scans including any other diagnostic tests performed.

What are the absolute contraindications for a parathyroid MIBI scan?

This study may not be suitable for pregnant women. The benefit versus risk should be discussed with the nuclear medicine specialist.

Women who are breastfeeding and people who are the primary or sole carer for small children may need to make special preparations after the test to stop breastfeeding for a short time and to avoid close contact with young children due to the small amount of radioactivity released for a while after the test. Patients should discuss this with their referring doctor or the nuclear medicine practice where they will have the test for details. See nuclear medicine for further information about the precautions to take with nuclear medicine studies for breastfeeding patients and those in close contact with children.

If the patient is unable or not willing to remain still for a prolonged period of time you may need to consider another procedure.

If the patient is claustrophobic you may need to consider another procedure.

What are the relative contraindications for a parathyroid MIBI scan?

  • Iodine-containing preparations such as CT contrast, in the last 8 weeks.
  • Thyroid disease and thyroid hormones.

These two will interfere if the nuclear medicine specialist requires a technetium subtraction image, where the thyroid gland is subtracted to clearly see if there is any parathyroid gland(s) highlighted.

What are the adverse effects of a parathyroid MIBI scan?

Generally there are no adverse reactions. However, on rare occasion the patient may experience a metallic taste that lasts a few moments.

Very rarely a patient could experience:

  • tingling;
  • flushing;
  • nausea;
  • erythema;
  • diffuse rash;
  • headache.

Are there alternative imaging tests, interventions or surgical procedures to a parathyroid MIBI scan?

  • Ultrasound is a good screening test for parathyroid adenomas, however, it lacks specificity.
  • CT imaging may prove complimentary.
  • A sestamibi scan preceded by a technetium scan is useful to subtract the thyroid gland, which would therefore make the detection of small parathyroid gland(s) easier to locate. SPECT-CT scans can further enhance the sensitivity and specificity for detection of parathyroid adenomas using sestamibi.
*The author has no conflict of interest with this topic.

Page last modified on 26/7/2017.

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