What is a parathyroid scan?
This Nuclear Medicine scan is used to investigate patients who have elevated calcium levels in the blood. One of the causes of raised levels of blood calcium is an often-benign tumour called a parathyroid adenoma. This is usually an enlargement of one of the four small parathyroid glands found behind the thyroid gland in the neck. This test can greatly aid the surgeon in performing a much easier and shorter operation to remove the tumour.
How is the scan performed?
The patient is given a small intravenous injection of radiotracer (Tc-99m sestamibi) and comfortable positioned for scanning using a gamma camera. Images are acquired intermittently over a two-hour period. The imaging usually also includes the technique known as SPECT (single photon emission computed tomography). This can be combined with low-dose computed tomography (CT) imaging to accurately demonstrate the anatomy in the neck and chest region.
How is the scan interpreted?
Normally the parathyroid glands are not seen on the scan because of their small size, but will show up when enlarged. The surrounding thyroid tissue also accumulates the radiotracer and on the early scans may blot out the parathyroid adenoma. Later imaging, however, will show more rapid clearance of the radiotracer from the thyroid tissue compared to that seen in the parathyroid adenoma .The adenoma therefore becomes more obvious.
PLEASE BRING ANY OTHER X-RAYS, ULTRASOUNDS, CT SCANS, MRI SCANS, MEDICATION LIST OR RELEVANT MEDICAL HISTORY ON THE DAY OF NUCLEAR MEDICINE SCAN