Test Overview
A
salivary gland scan uses a special camera and a
tracer (radioactive chemical) to take pictures of the
salivary glands
. This can help your doctor find the cause of dry mouth
(xerostomia) or swelling in the salivary glands.
During a salivary gland scan, the tracer liquid is put into a vein
(IV) in your arm. The tracer moves through your blood
and into the salivary glands. A special camera takes pictures to show how much
tracer stays in the salivary glands.
Why It Is Done
A salivary gland scan is done to:
- Find the cause of swelling in the major salivary glands. Swelling
may be caused by an infection (abscess),
inflammation, or a pocket of fluid (cyst).
- See if a growth in the
parotid gland
is a benign Warthin's tumor or if it may be
cancer. - Find the cause of dry mouth (xerostomia). Several problems
can cause dry mouth, such as a blocked salivary duct, a growth in a salivary
gland, or
Sjögren's syndrome.
How To Prepare
Before the salivary gland scan, tell your health professional if
you:
- Are or might be pregnant.
- Are
breast-feeding. You will need to use formula for 1 to 2 days after the scan so
you won't pass the tracer to your baby. You should throw out any breast milk
you collect during this time.
- Have had other nuclear scans
recently. If so, the salivary gland scan may need to be delayed.
Talk to your doctor about any concerns you have regarding the need
for the test, its risks, how it will be done, or what the results may mean. To
help you understand the importance of this test, fill out the
medical test information form
(What is a PDF document?)
.
How It Is Done
A salivary gland scan is usually done by a nuclear medicine
technologist. The pictures are usually interpreted by a
radiologist or
nuclear medicine specialist.
Take off any jewelry that may get in the way of the scan.
During a salivary gland scan, you will sit with the camera placed
at your neck. A small amount of the
tracer is put in your vein (IV).
The camera will scan for radiation released by the tracer. The
pictures are taken every few minutes during the scan. You need to stay very
still during the scan so the pictures are not blurry.
You may be asked to suck on a lemon after the first pictures are
taken. This causes your salivary glands to release more saliva. Then more
pictures are taken.
A salivary gland scan takes about 1 hour.
How It Feels
You may not feel pain from the IV needle or you may feel a quick
sting or pinch. A salivary gland scan usually does not cause pain.
You may find it hard to lie still during the scan.
Risks
There is a slight chance of damage to cells or tissue from
radiation, including the low levels of radiation used for this test. But the
chance of damage from the X-rays is usually very low compared with the benefits
of the test.
Allergic reactions to the tracer are very rare.
In some cases, soreness or swelling may develop at the IV site.
Apply a moist, warm compress to your arm to relieve these symptoms.
Results
A
salivary gland scan uses a special camera and a
tracer (radioactive chemical) to take pictures of the
salivary glands
.
The results of a salivary gland scan are usually available within 2
days.
Salivary gland scan | Normal:
| The tracer moves evenly through the salivary glands and is
released normally into the mouth. |
The salivary ducts leading from the salivary glands are not
blocked. Saliva is released in response to sucking on a lemon. |
| Abnormal:
| The tracer does not move evenly through the salivary
glands. A pocket of fluid (cyst), a pocket of infection (abscess), or a tumor or other growth may be
present. |
The tracer may not flow normally from the salivary glands
into the mouth. This may be caused by a tumor pressing on the duct, a stone in
the duct, or inflammation of the duct. |
The flow of tracer through the salivary glands is
decreased. This may indicate a condition, such as
Sjögren's syndrome. |
The amount of tracer in the salivary glands in front of the
ear is greatly increased. This may indicate inflammation or infection of the
parotid glands (parotitis). |
What Affects the Test
Reasons you may not be able to have the test or why the results may
not be helpful include:
- Pregnancy. A salivary gland scan is not usually
done during pregnancy because the radiation could harm the
baby.
- The inability to stay still during the test.
What To Think About
- In North America, a salivary gland scan is
rarely done. Most often, a
CT scan or
magnetic resonance imaging (MRI) is done to look at
the salivary glands. An
ultrasound scan also may be done to look at the
salivary glands. But a salivary scan is the only test that can see how well the
salivary glands are working.
- Although a salivary gland scan may be
done to evaluate dry mouth caused by
Sjögren's syndrome, it usually is not used to diagnose
this disease. But a salivary gland scan may be used to diagnose Sjögren's
syndrome in a person who has
rheumatoid arthritis.
References
Other Works Consulted
Fischbach FT, Dunning MB III, eds. (2004).
Manual of Laboratory and Diagnostic Tests, 7th ed.
Philadelphia: Lippincott Williams and Wilkins.
Credits
| Author | Maria G. Essig, MS, ELS |
| Editor | Susan Van Houten, RN, BSN, MBA |
| Associate Editor | Tracy Landauer |
| Primary Medical Reviewer | Adam Husney, MD - Family Medicine |
| Specialist Medical Reviewer | Paul D. Traughber, MD - Radiology |
| Last Updated | September 11, 2007 |