Parathyroid Glands Can be Hard to Find. Most Sestamibi Scans are done poorly.
This page discusses ways to locate the diseased parathyroid gland.
Sestamibi Scan, MRI, CT, and Ultrasound Discussed. Most scans are done poorly!

If you have parathyroid disease, the overwhelming chances are that just one of your parathyroid glands has gone bad (over 91% have just one bad gland). Parathyroid disease will be cured if the surgeon takes out that one bad gland!  But, there are four parathyroids and they can be located all over the neck. The key to a successful operation is for the surgeon to FIND the bad parathyroid... Hopefully, you have a surgeon that can quickly and easily find the bad parathyroid tumor. With modern tests your surgeon will have a pretty good idea which parathyroid is bad BEFORE the operation! But...don't keep having tests and more tests, instead find an expert and let him/her take care of it. Don't let your endocrinologist or family doctor keep ordering the tests that are on this page! As much a positive role these doctors play in this disease, they really should not be ordering any more than ONE localizing test (preferably they will order ZERO x-rays!). Let the expert parathyroid surgeon do this! Almost all of the time these tests are completely unnecessary!  And... as you will read below, most sestamibi scans are done very poorly. Therefore, most of you reading this page will get a negative scan and everybody will get confused and all of a sudden things become difficult. The problem is that most places can't do good scans... Don't get confused, and do NOT put too much emphasis on these scans. Every single day we get emails from patients who tell us that they have hyperparathyroidism and their doctor sent them for a sestamibi scan and the scan is negative---then everybody goes into a "tizzy" because they don't understand this page.  Most places cannot do parathyroid sestamibi scans well and they are negative because they don't do it right. The emphasis should be placed on choosing the most experienced surgeon you can. STOP getting all these tests! Find an expert parathyroid surgeon and let them find the tumor!

Parathyroid glands have the most un-predictable anatomy in the human body. Parathyroid glands are typically found on the back side of the thyroid gland. In fact, about 85% of parathyroid glands are found behind the thyroid gland. The picture above shows the BACK SIDE of the thyroid gland, showing that the four parathyroid glands are closely associated with the back of the thyroid. HOWEVER, because of how parathyroid glands are formed (when we are in our mother's womb), they can be anywhere in the neck from just below the jaw--all the way down into the chest next to the heart. The picture on the left shows the location of the thyroid gland in a patient's neck. The black dots outline the positions that the left parathyroid glands can be found. You can see that 15% of parathyroid glands are NOT found next to the thyroid, thus these little guys can be very hard to find! Remember, parathyroid glands are only the size of a grain of rice (half of a pea) when they are normal, and get to be about the size of a grape when they develop a tumor (called a parathyroid adenoma) and make too much parathyroid hormone. Click Here to read more about parathyroid anatomy. This will also help you understand why the experience of the surgeon is so important to a good outcome following parathyroid surgery. Remember, almost all patients with hyperparathyroidism have a single bad gland... it grows into a tumor. These tumors are typically about the size of a grape, however, sometimes they are smaller--about the size of an olive. But, the tumor will continue to grow if it is not removed, and if its been present for a number of years it can get to be the size of a golf ball or even bigger! Yep, the size of the tumor often correlates with how long it has been present. This tumor will NOT go away by ignoring it or by some medications to treat your blood pressure and depression. It is a tumor (a benign tumor, but a tumor none the less), and it should be removed. Make sure your surgeon has done lots of these operations so he/she knows were to find the tumor! We have a page of pictures showing the parathyroid tumors we took out of patient's necks over a 2-week period.

If you want to read more about parathyroid anatomy and how the parathyroid glands can be high in the neck or low in the chest, then read our page on Parathyroid Anatomy.  BE CAREFUL... everybody that reads this page thinks that they are one of the rare patients with a parathyroid tumor in their chest... IT IS RARE... You do NOT have a parathyroid tumor in your chest! 

Many experts feel that no study or test is required to "identify" the diseased parathyroid gland (or glands) prior to an operation for hyperparathyroidism. They feel that surgeons with enough experience can find the problem gland and remove it to cure the disease in about 95 % of all cases...without any pre-op tests. Of course what they don't tell you is that this often requires the patient to be under general anesthesia for two to five hours so the surgeon can make a large incision and do an extensive dissection of your neck. What they also don't tell you is that there are only a few surgeons in the US that fall into the "expert" category who can demonstrate a 95% cure rate (most general surgeons have a cure rate between 85 and 90%).  The days of making a big incision and exploring the entire neck on all patients with parathyroid disease ARE GONE! The concept is correct, however, and wherever you read about parathyroid disease they will tell you... you want an expert surgeon.

It is now well accepted that the preferred way to perform parathyroid surgery is to make an attempt to identify the over-active parathyroid gland preoperatively (before the operation). It is well established now that this localizing step will allow a shorter operation and a more successful operation. There no reason for any patient to undergo parathyroid surgery without the surgeon and radiologist performing at least ONE localizing study prior to the parathyroid operation. Note: Not all patients will have a localizing test that shows the bad gland. Some people (about 3-4%) will have 4 bad glands (read more), thus their test will be negative (it can't possibly show 1 bad gland if there are 4 bad glands). Even some people with only one bad parathyroid will NOT have a positive test even if the test is done perfectly. The problem is that often the tests are not done very well. Keep reading more to understand this.

Which Localizing Test is the Best?

Sestamibi scanning is the best way to find a parathyroid tumor. However, there are several other tests used that can occasionally discover which parathyroid gland is the bad parathyroid gland.  Some tests (ultrasound, CAT scan, and MRI scan) simply use pictures of one form or another to find a BIG gland. These studies CAN NOT determine which gland is making too much hormone, they just look at parathyroid SIZE. Of course, there are other small things in your neck (like lymph glands and thyroid nodules) which can give false tests.  Thus, CAT Scans, and MRI Scans should NOT be used to find a bad parathyroid gland. Let us repeat this: IF YOUR DOCTORS ARE GETTING A CAT SCAN OR MRI SCAN ON YOU... you may want to print this and educate them. THEY CLEARLY DON'T SEE PATIENTS WITH PARATHYROID DISEASE VERY OFTEN--or they would know that MRI and CAT scans show less than 5% of ALL parathyroid glands... Therefore, if you have a CAT scan or MRI scan, you have a 95% chance of having a test that costs money, takes time, and won't help a thing (except confuse people). These tests do not show parathyroid tumors very well.  Ultrasound exams done at your local radiology center or the radiology department of a hospital will also not show the tumor in most cases!  Less than 12% of these ultrasound scans will show the tumor... not because the tumor isn't there... but because this test is HIGHLY dependant upon the skill of the person doing the test. If they don't do this every day, the scan will not be useful! (like taking a photograph of your kids at night without a flash--you can't see the kids, but the are still there). Ultrasound scans done by endocrinologist or your endocrine surgeon in their office can be extremely helpful and this is a good thing for you to have. If they are nod doing it, you probably don't want it. We would NEVER send a patient for an ultrasound test.

When people have a scan to find their bad parathyroid gland and it doesn't show anything, they get confused. If the right techniques are not used during your x-ray, it's like taking a picture of the planet Saturn with your cell-phone camera. You take the picture but the photo doesn't show the big planet with the rings.  It's not because the planet has disappeared, it's because you used the wrong camera, the wrong film, and the wrong lens to photograph the planet. This occurs hundreds of times per day when patients are sent to their local radiology department for some x-ray to help find the bad parathyroid gland. If it's a CT scan or MRI, then you are using the wrong camera and it will be a worthless test 95% of the time. Shame on the doctor who ordered a CAT scan or an MRI test. If you get an ultrasound, then it will be worthless 88% of the time because it is not very good at finding most parathyroid tumors unless it is done by your endocrinologist (and then only 50% of the time it will show the tumor). If you get a sestamibi scan, then the chances of it showing the tumor in your neck is between 0% and 95% depending on who does the scan and how often they do this type of scan. The sestamibi is very dependant upon the techniques the technician uses... which type of film, what lens, and what filters they use when doing the test. 

Having said all of this, ideally it would be best if we could identify the location of the parathyroid gland that is making too much hormone.  After all, the problem with parathyroid tumors is NOT that they get cancerous, the problem is that they make too much parathyroid hormone and the hormone is what causes the problems. The Sestamibi scan is the test that is now the preferred way to find a bad parathyroid gland. The Sestamibi scan does not care how big the parathyroid is, it just looks for parathyroids that are over-active (the one that is making too much parathyroid hormone). This is also the key to MIRP Minimally Invasive Radioguided Parathyroid surgery and ALL forms of mini-parathyroid surgery. BOTTOM LINE... NOBODY NEEDS ANY X-RAY OR SCAN UNTIL THEY SEE THE SURGEON, AND THE SURGEON SHOULD ORDER ONE TEST... A HIGH QUALITY SESTAMIBI SCAN. Unfortunately, at least 75% of you reading this will have already undergone some silly test that didn't help. You will know what we are saying is true, but your inexperienced doctor will order test after test...after test. Stop the silliness.

A dangerous trend has emerged in the past few years that you must know about and avoid. Some endocrinologists and/or surgeons will want to prove that what they believe is a parathyroid tumor on a scan is really a parathyroid tumor, so they will biopsy this gland with a needle. This is called a FNA or "fine needle aspiration" biopsy, or "needle biopsy" of the parathyroid gland. THIS IS DANGEROUS AND SHOULD ALMOST NEVER BE DONE. This will cause death to some of the parathyroid tumor, and when it heals with scar tissue (like all tissues heal), the scar tissue can involve the voice box nerve. This will cause tremendous troubles for the surgeon and increases dramatically the chance that you will never talk again. Furthermore, the scarring that occurs will look like cancer under the microscope resulting in the pathologist determining that your parathyroid tumor was a cancer... even when it was not. Some really good endocrinologists can stick a very fine needle (a 27 gauge needle) into the gland with much less chance of causing a problem. However, if you have a biopsy of your parathyroid gland by a doctor that uses an 18 or 20 gauge needle, this is malpractice. We will not accept patients into our clinic for surgery if they have had a parathyroid biopsy using an 18 or 20 gauge needle. If you have had a biopsy of your parathyroid gland with a smaller needle, then we will accept you into our practice but will require you to sign a written statement acknowledging that the needle biopsy greatly increases the difficulty of the operation with increased risks for complications, and increased difficulty for the pathologist.  To read our recent publication on this topic in one of the major Endocrinology journals, click here: Diagnostic Aspiration of Parathyroid Adenomas Causes Severe Fibrosis Complicating Surgery and Final Histologic Diagnosis. Thyroid. 2007 Sep 22

The following list describes briefly the different tests which may help a surgeon or endocrinologist find the diseased parathyroid gland which is over secreting parathyroid hormone.

The Sestamibi Scan is now the preferred method for identifying a diseased parathyroid gland prior to an operation. No other test comes close to its accuracy. Almost 100 percent correct when it shows a single gland when done at some hospitals that do LOTS of these scans. There are technique differences which make these scans at some hospitals much better than they are at other hospitals. Regardless of where it was performed however, if it shows a single adenoma, it is nearly always correct! Again, this should be the ONLY test you get. If it is negative, this is almost ALWAYS due to the fact that the technician who performed the scan is not good at it (rare disease so they have little experience doing the scan). At the Norman Endocrine Surgery Clinic, about 93% of the scans performed between 2003 and 2007 at some other institution which were NEGATIVE became POSITIVE when these  same patients had this scan done in Tampa. This is by far the best test regardless of where you live, but some places do many more than others so they are much better at it. 
Go to the page on Sestamibi scanning.  This is a MUST READ section.

SPECT scanning is a mechanism by which a three dimensional picture can be obtained following injection of the Sestamibi drug. Sometimes this can be very helpful, but is not usually needed prior to the first parathyroid operation. This test is way over used, and is usually negative because of the techniques used (technicians who don't do this very often). The primary reason that this test is done is because (1) the radiologists can charge for a second scan, or (2) the endocrinologist ordered it thinking it can help.  We review over 4,000 sestamibi scans per year, and only about 10% of them include SPECT scanning. It is almost never helpful and should not be done routinely. We NEVER use SPECT scanning unless the tumor is in the chest next to the heart. In our opinion, this is the only time SPECT scanning should be used.
More information on SPECT scanning.
View a 3-D reconstructed SPECT scan video.

MRI scans are valuable very rarely (almost never) because MRI scans don't show parathyroid tumors. At best, an MRI will find less than 8% of parathyroid tumors, therefore, the indications for getting this scan are VERY few. It is NOT a routine test! This test is only for patients who have had one or more FAILED parathyroid operations, or somebody who has a parathyroid identified on Sestamibi next to their heart. If your doctor is ordering this test PRIOR to you having an operation, then your doctor is NOT experienced in this disease.  IT IS INAPPROPRIATE TO GET AN MRI SCAN ON ANY PATIENT WHO HAS NEVER HAD AN OPERATION (and some feel all patients!). This test is for VERY RARE PATIENTS--- because it almost NEVER WORKS!  If your doctor orders this test for you, take this page to them and educate them. NEVER GET AN MRI SCAN-- IT WILL NOT SHOW A PARATHYROID TUMOR! In our opinion, it is NEVER appropriate to get an MRI scan for parathyroid disease. NEVER. Not under any circumstances. NEVER! And, it is such a worthless test for parathyroid disease that insurance companies should not pay for it. I hope I made this clear!
More information on MRI scanning for Parathyroids.

CT scans are used much less frequently since the introduction of the Sestamibi scans. They can occasionally be helpful, but getting a CT scan prior to a first operation for hyperparathyroidism is NEVER warranted.  THIS TEST SHOULD NEVER BE DONE!! It does not show parathyroid tumors. Sometimes a patient will have a failed operation and so the doctors start ordering lots of x-rays, including CAT scans. Of course, if you had an experienced surgeon, you are very UNLIKELY to have a failed operation. Thus, get an expert surgeon and don't worry about wasting your time on these dumb tests. Again, if you have never had a parathyroid operation, then you should NEVER get this test. In our opinion, this should NEVER be done under any circumstances unless it is part of a "fusion" scan.
More information on CAT scanning for Parathyroids.

Ultrasound is less costly than CAT scans and MRIs, they are easily performed, carries no significant risks, and can occasionally be useful in localizing a parathyroid adenoma. Overall, not very good [very inaccurate in most settings]. Only about 12-15 percent of ultrasound scans are positive if they are performed by the local radiologist--therefore, don't waste your time on this scan unless it is performed by your endocrinologist or your surgeon in his/her office. This test has been way overused in the past, and has been replaced by the Sestamibi scan for accuracy in finding parathyroid glands. It can be helpful for those rare patients who are undergoing a second operation for hyperparathyroidism. This is in direct contrast to the utility of ultrasound for examining thyroid glands and thyroid nodules. Ultrasound is very accurate when used to examine the thyroid but not for parathyroids--unless done by your doctor!  If your endocrinologist or your surgeon has an ultrasound machine in his/her office, then this test can be very good at looking at parathyroids and finding parathyroid tumors. It is our opinion that an ultrasound done by the endocrinologist or surgeon is an OK test and is worthwhile in about 50-60 percent of the time. However, if your doctor just orders this test to be done by some technician at the local hospital or radiology center, then you can bet that this test has a high likelihood of not showing the parathyroid tumor they are looking for. This is one of the reasons the cost of medicine is going out of control...doctors ordering too many tests even when the tests have little chance of helping.

SESTAMIBI SCANS RESULTS...
WHAT TO DO ABOUT YOUR NEGATIVE SESTAMIBI SCAN.

We get to review about 4,500 sestamibi scans per year. These come to us from many hospitals across the US. Sestamibi scans are extremely variable depending on the techniques used. These are NOT regular x-rays which every hospital can perform. Sestamibi scans require the highest degree of technician input. The use of special filters, patient placement, etc, are very important. Therefore, MOST scans done in the US are not very good. About 30% of the scans in the US are WORTHLESS, another 30% are terrible or poor quality.

Sestamibi scanning is often not done correctly, and done for the wrong reasons, and interpreted wrong. Be careful of your sestamibi scan. It can be extremely helpful if your sestamibi scan is positive, but if your scan is negative it doesn't mean much. It does NOT mean you don't have parathyroid disease if your scan is negative (we will say this 10 times so you understand it!).

If you have a scan that is "negative" it does NOT mean that you don't have parathyroid disease.  It's not negative because you don't have a parathyroid tumor, usually its negative because they do not know how to do this test and a test done poorly won't show the tumor. Worse yet, your doctor may become confused and tell you to do nothing about your disease--all because some technicians don't know what they are doing! NOTHING ON THIS WEB SITE IS MORE IMPORTANT THAN THIS SIMPLE PARAGRAPH!!! DO NOT MAKE THIS MISTAKE!

NOTE: about 1/3 of ALL sestamibi scans we review fall in to this "worthless" category. Please note....this is a reflection of the quality of the x-rays, and NOT a reflection of the quality of the endocrinologists or surgeons who ordered the x-rays. 

If there was one thing that you should take away from this page it is this..... sestamibi scans are very nice tools to help the surgeon find your tumor, but these scans are difficult to do and most places don't do them well. Some very good quality sestamibi scans are negative.... and the patient still has the disease. Some scans are negative because the scan was done poorly, and of course, these patients have parathyroid disease. The results of the scan should never be used to determine who goes to surgery and who does not. Using the scan to make this decision is not correct. Almost 75% of the patients we operate on and remove a parathyroid tumor from... came to see us with a negative sestamibi scan done somewhere else prior to coming to see us. If you have a negative sestamibi scan, then you still have a 95% chance of having a single adenoma as the cause of your disease. Find an expert parathyroid surgeon and get it removed!

This page was last updated 12/05/2007

More information on the use of Ultrasound for Parathyroids.
More about ultrasound for Thyroid Disease. This will take you to a large web site called EndocrineWeb.