4D Parathyroid CT Scan
A 4D parathyroid CT scan is a newer imaging study that can be used to locate an abnormal parathyroid, and it is the one of the most accurate localization studies.
These difference are visible when a CT scan is done at different times after the contrast dye is injected into the bloodstream. This type of scan shows the parathyroid anatomy in great detail along with the blood vessels that are feeding the parathyroid, which helps show an abnormal parathyroid gland and the tissue around it,
including the thyroid gland, blood vessels, breathing tube, and esophagus. It will show if an abnormal parathyroid is close to the area of the voice box nerve. The scan can also show a gland that is not in the normal position (ectopic parathyroid gland), anywhere from the upper neck all the way down into the chest.
A 4D parathyroid CT scan is used to identify an enlarged parathyroid better than the other scans mentioned on this page. However, it also exposes a patient to a high dose of radiation. And although we have modified our 4D CT scan protocol to minimize the dose of radiation, radiation exposure is still a consideration, especially in younger patients. We firmly believe this is the study of choice in patients who have had previous parathyroid surgery and had recurrence or persistence of the disease, along with newly diagnosed hyperparathyroid patients who have a negative ultrasound and PTH levels that are below-average
PROS – 1. Very accurate. 2. Can show parathyroid glands anywhere in the neck and chest, even if they are hidden behind the voice box, breathing tube, chest bone, or collarbone. 3. More anatomical detail than a sestamibi scan or SPECT scan. 4. More accurate, even when a tumor is small and PTH levels are only slightly elevated.
CONS – 1. Exposure to radiation