A sialogram is an x-ray of the salivary ducts and glands.
The salivary glands are located on each side of the face. They release saliva into the mouth.
How the Test is Performed
The test is performed in a hospital radiology department or a radiology facility. The test is done by an x-ray technician. A radiologist interprets the results. You may be given a medicine to make you calm before the procedure.
You will be asked to lie on your back on the x-ray table. An x-ray is taken before the contrast material is injected to check for blockages that might prevent the contrast material from entering the ducts.
A catheter (a small flexible tube) is inserted through your mouth and into the duct of the salivary gland. A special dye (contrast medium) is then injected into the duct. This allows the duct to show up on the x-ray. X-rays will be taken from several positions. The sialogram may be performed along with a CT scan.
You may be given lemon juice to help you produce saliva. The x-rays are then repeated to examine the drainage of the saliva into the mouth.
How to Prepare for the Test
Tell the health care provider if you are:
Allergic to x-ray contrast material or any iodine substance
There is low radiation exposure. X-rays are monitored and regulated to provide the minimum amount of radiation exposure needed to produce the image. Most experts feel that the risk is low compared with the potential benefits. Pregnant women should not undergo this test. Alternatives include tests like an MRI scan that do not involve x-rays.
Miller-Thomas M. Diagnostic imaging and fine-needle aspiration of the salivary glands. In: Flint PW, Haughey BH, Lund LJ, et al, eds. Cummings Otolaryngology: Head & Neck Surgery. 6th ed. Philadelphia, PA: Elsevier Mosby; 2015:chap 84.
Alan Lipkin, MD, Otolaryngologist, private practice, Denver, CO. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.