A sestamibi scan is used to evaluate the function of the parathyroid glands; these four glands are located in the neck and help manage the body’s calcium levels. To better understand the impact of a sestamibi scan, let’s examine this parathyroid gland assessment in detail.
What Is a Sestamibi Scan?
A sestamibi scan was introduced in the 1990’s, and today, is used in hospitals around the world to help a doctor identify diseased parathyroid glands. With a sestamibi scan, a radioactive agent is injected into a patient’s veins. The radioactive agent is then absorbed by an overactive parathyroid gland, a problem that commonly affects individuals dealing with hyperparathyroidism (HPT).
What Is the Link Between HPT Symptoms and a Sestamibi Scan?
HPT causes one or more parathyroid glands to produce excess amounts of parathyroid hormone (PTH), which helps regulate calcium levels in the blood. When this happens, an affected parathyroid gland becomes enlarged due to overproduction of PTH. An overactive parathyroid gland also increases calcium levels in the blood, along with raises the risk of health problems that can affect an individual’s bones, muscles, brain, heart, kidneys, and digestive system.
Thanks in part to a sestamibi scan, an individual who displays HPT symptoms can identify which gland is malfunctioning. During a sestamibi scan, the body absorbs a radioactive agent that travels to an overactive parathyroid gland, and a doctor can use single photon emission computed tomography (SPECT) scans to produce 3D images of the parathyroid glands & other neck structures. If a doctor finds the radioactive agent is present in one or more of the parathyroid glands, then the surgery can become more focused and minimally invasive.
Is a Sestamibi Scan the Only Test Required for a Doctor to Diagnose HPT?
A sestamibi scan is valuable, as it helps a doctor identify one or more overactive parathyroid glands that may contribute to HPT symptoms. Yet a sestamibi scan has a lot of nuances that make it not be the best test to identify the abnormal gland. At the CENTER we rarely use the sestamibi scan because we find the other scans to be more informative:
- Ultrasound: Often the first study that a doctor performs to identify an abnormal parathyroid, an ultrasound does not require the use of radiation. Conversely, an ultrasound involves the use of soundwaves to analyze structures beneath the skin, such as the thyroid, parathyroid, and blood vessels.
- 4D Parathyroid CT Scan: One of the most accurate HPT localization studies available, a 4D parathyroid CT scan helps a doctor identify an abnormal parathyroid gland and affected tissue. A 4D parathyroid CT often helps a doctor quickly detect an abnormal parathyroid gland; at the same time, this evaluation generally exposes a patient to higher levels of radiation than other HPT localization studies.
There is no one-size-fits-all approach to HPT localization studies, and one or more of the following tests may be used in combination with a sestamibi scan to help a doctor identify an abnormal parathyroid gland. Regardless of the tests used for HPT diagnosis, a doctor always provides a patient with full details about HPT localization studies before any evaluations are completed. This ensures that a patient knows exactly what to expect prior to a sestamibi scan or any other HPT localization studies.
What Is the Best Way to Prepare for a Sestamibi Scan?
Minimal prep work is required for an individual who plans to undergo a sestamibi scan. Individuals can eat and drink as they normally would leading up to a sestamibi scan. Additionally, patients won’t have to remove any clothing or jewelry as part of a sestamibi scan.
For women who believe they may be dealing with HPT and are planning to undergo a sestamibi scan, however, it is important to tell a doctor if you are pregnant or breastfeeding. Since a sestamibi scan involves the use of a radioactive agent, this form of HPT testing may not be suitable for women who are pregnant or breastfeeding. Fortunately, alternative tests may be used to help pregnant or breastfeeding women receive a proper HPT diagnosis.
What Should You Expect During a Sestamibi Scan?
On average, a sestamibi scan takes 1.5 to 2 hours to complete, so a patient should set aside at least a couple of hours for the test. Typically, a doctor will take multiple sestamibi scans of a patient’s parathyroid glands. The initial sestamibi scan of the parathyroid glands is performed within about 10 minutes of injection of the radioactive agent (it’s very important that the first scan is done within 10 minutes otherwise it will not be as accurate). A second sestamibi scan is also completed approximately 90 minutes after this injection. Meanwhile, the first sestamibi scan usually requires about 20 minutes to complete, and a patient can often go home about 45 minutes after the second scan.
When a sestamibi scan is performed, a state-of-the-art camera is used to identify the radioactive agent in the body. The camera is placed close to a patient’s head but won’t directly touch the head. A patient is asked to remain still as the camera captures images of the parathyroid glands. The camera also moves around a patient to capture images of the parathyroid glands from different angles.
Once a sestamibi scan is complete, a patient can resume their normal activities. The side effects of a sestamibi scan are minimal. Some patients experience a metallic taste inside the mouth after the radioactive agent is injected into the body, but this taste often disappears on its own within minutes of injection.
A follow-up appointment is usually scheduled with a few days a sestamibi scan. At this time, a doctor can discuss their sestamibi scan findings with a patient and offer a personalized treatment recommendation.
What Are the Dangers Associated with a Sestamibi Scan?
A sestamibi scan is considered to be a secondary option for individuals who experience HPT symptoms, if other scans fail then we would consider using this scan. But like any test that involves the use of a radioactive agent, there are risks associated with a sestamibi scan.
Before undergoing a sestamibi scan, it is crucial to consult with an expert parathyroid gland surgeon. This ensures that an individual can learn about parathyroid anatomy, as well as receive insights into different aspects of HPT. If a surgeon believes a sestamibi scan is a safe and viable option to identify one or more abnormal parathyroid glands, he or she can then offer insights into the scan and any dangers associated with it. Also, in this scenario, the surgeon can respond to a patient’s sestamibi scan concerns and questions and help this individual make an informed decision about HPT localization studies.
What Are the Pros and Cons of a Sestamibi Scan?
There is a lot to like about the use of a sestamibi scan to diagnose an abnormal parathyroid gland. Research indicates that a sestamibi scan helps a doctor identify an abnormal parathyroid gland in approximately 85% of all cases when PTH levels are over 150 ng/ml. The accuracy is much lower at lower PTH levels.
A sestamibi scan is not use to help a patient find out if he or she is coping with HPT. It is purely to localize where the abnormal glands may be. A sestamibi scan must be performed by a highly trained and experienced doctor; otherwise, a patient risks inaccurate sestamibi scan results.
Is a Sestamibi Scan Used to Treat HPT Symptoms?
A sestamibi scan is used to help a doctor locate the abnormal glands — not treat them. However, if a sestamibi scan and other localization studies reveal the location of the abnormal gland, he or she can undergo a minimally invasive parathyroidectomy.
Parathyroidectomy is a minimally invasive surgical procedure that only requires about 20 minutes to complete. The surgery involves the use of a small incision, and it is performed under local anesthetic. Also, parathyroidectomy has a high success rate and low risk of complications.
Is a Sestamibi Scan Right for Me?
The decision to undergo localization studies for HPT symptoms is rarely simple. There are many factors to consider, and as such, it is important to partner with a doctor who understands what it takes to accurately diagnose and properly treat HPT.
When it comes to HPT diagnosis and treatment, Dr. Babak Larian is happy to help individuals in any way he can. Dr. Larian can help you decide which scan is the most appropriate for you to accurately locate the abnormal gland. He also helps a patient determine the appropriate treatment for their HPT symptoms, as well as performs parathyroid surgery with a cure rate of nearly 97%
Schedule an HPT Treatment Consultation with Dr. Larian
Dr. Larian is available to discuss sestamibi scans and other localization studies, and he can help an individual discover the best way to treat their HPT symptoms. To learn more about HPT or to schedule an HPT treatment consultation with Dr. Larian, please contact us online or call us today at 310.461.0300.
