Reasons & Procedure For Conducting a Sestamibi Parathyroid Scan

Submitted on March 27, 2012

Sestamibi Parathyroid Scan

Considering that a parathyroid sestamibi scan is essentially used to locate parathyroid endenomas, it helps to know exactly what a parathyroid adenoma is. The parathyroid glands are located just behind the thyroid gland and play a very significant role in the release of hormones that regulate a number of substances in the body including vitamin D and calcium which aid in one's stability and overall health. When a tumor develops on these glands, they are known as parathyroid adenoma's and, although not cancerous, needs attention as they are known to cause a number of other health issues.

Reason Why It is Conducted

The first systemibi parathyroid scan was accomplished in the early 1990's and is now so commonly used that it is performed in practically every country over the United States of America. It utilizes Systemibi, which is a small protein like substance that is labeled with the radio pharmaceutical - technetium99. This agent is a mild but safe radioactive agent that is injected into the veins of the patient suffering from hyperthyroidism and is absorbed by the overactive parathyroid gland. Under normal circumstances, the parathyroid glands are inactive when there is a high amount of calcium in the bloodstream. They do not absorb the radioactive particles- thereby enabling the scan to be effective only when dealing with overactive parathyroid glands.


Once the systemibi has been introduced into the patients system, a gamma camera is placed over the patient's neck. Images are then captured that are accurate enough to show the overactive gland. By being able to correctly identify which of the four parathyroid glands is overactive, the surgeon is able to remove only the gland that is producing an excessive amount of parathyroid hormone. This gland is no longer under the biochemical control of the body. The other 3 normally functioning glands are untouched. The scan may take some time to show up significant results and sometimes the determination can only be made about three or four hours later when the normal parathyroid glands fade away but the malfunctioning gland retains its work rate. If the surgeon or presiding doctor locates a number of the glands showing up during the scan, there is a likelihood that more than one of your parathyroid glands are affected. However, it must be kept in mind that even if no 'hot spots' are detected during the scan resulting in a negative scan, this is not definitive proof that you are not affected by hyperthyroidism. It should be noted that about 15% of all patients that get negative tests still suffer from the condition.