A sialogram is a test used to diagnose a blocked salivary gland or duct in your mouth. The procedure uses X-rays. It is also called a ptyalogram.
The salivary glands are located on each side of your face. You have three pairs of major salivary glands. The parotid glands, which are the largest, are located inside each cheek. They are situated above your jaw in front of your ears. The submandibular glands are located on both sides of your jaw below the jawbone. The sublingual glands are located on the bottom of your mouth under your tongue.
Salivary glands release saliva into your mouth through salivary ducts. A free flow of saliva to the mouth is important for digestion and general oral health.
Functions of Saliva
When food enters your mouth, saliva adds moisture to it. The wetness helps with chewing and swallowing. It prevents choking. Enzymes in saliva initiate the digestion process before food is swallowed.
Saliva also works to keep the mouth clean. It helps wash bacteria and food particles away. Moisture from saliva also helps keep oral appliances, such as dentures and retainers, secure in your mouth.
A sialogram is used to evaluate blockages in a salivary duct or gland.
Your physician may recommend a sialogram if you have any of the following symptoms:
- a constant abnormal or foul taste in your mouth
- inability to fully open your mouth
- discomfort or pain when opening your mouth
- dry mouth
- mouth pain
- face pain
- swelling over your jaw in front of your ears
- swelling of your face or neck
While these symptoms occur in the salivary glands, they often are a result of:
- infections in the mouth or elsewhere in the body
- salivary duct stones
- salivary duct infections
- oral cancer or other types of cancer
- sarcoidosis: a condition in which patches of inflammation occur throughout the body
- Sjögren’s syndrome: an autoimmune disorder that causes dry mouth and eyes
- abdominal surgery
- cirrhosis of the liver
Salivary gland tumors are rare. When they do exist, they occur most often in the parotid gland. The growths slowly increase in size, expanding the gland.
A sialogram is normally administered as an outpatient procedure. It may be performed in the radiology department of a hospital or in your physician’s office.
Typically, a sialogram takes about 30 minutes. If the duct opening is difficult to locate, it may take longer.
A sialogram is performed by a physician or X-ray technician. It usually involves the following steps:
- You will be given a germ-killing mouthwash.
- A sedative may be used to help you remain calm.
- In some cases, general anesthesia may be used. This is done if you are unable to remain still.
- You will lie on your back on an X-ray table.
- You will have to open your mouth very wide. No numbing agent is used. The procedure will only cause minimal discomfort.
- An X-ray will be taken. This will show if there are any stones that might prevent the contrast material (dye) from entering the ducts and reaching the gland.
- A small, flexible tube called a catheter will be inserted in the opening of the salivary duct.
- You may be asked to hold the tube in place.
- The technician will inject contrast material into the duct. You may experience pressure and some discomfort.
- After the dye fills the salivary gland, it will be visible by X-ray.
- Your physician may need to examine the salivary gland from different angles. You may have to turn your head in different directions. You may also need to hold your breath periodically. This helps you stay still for the X-ray images.
- You may be given lemon juice to increase the amount of saliva in your mouth.
- Additional images will be taken to observe how your saliva drains into your mouth.
After your sialogram is over, the contrast material will drain into your mouth. You may be instructed to massage your salivary glands. This will aid in draining the dye.
The dye may taste bitter. It is safe to swallow the dye.
After your sialogram, you can return to your normal diet and activities.
A sialogram will expose you to minimal amounts of radiation. However, the test can help your doctor acquire important information about your health. Therefore, the risk of radiation exposure is considered acceptable. Special considerations may be needed for pregnant women, women who are breastfeeding, and children. They have an increased risk of suffering harm from radiation.
With a routine sialogram, there is a minor risk of swelling and tenderness after the procedure. Infection is another rare complication. Contact your physician if you experience:
- soreness or pain that continues after 24 hours
- swelling or bleeding of the salivary duct
A sialogram is a minimally invasive technique. However, there is a small risk of damage or puncture to the salivary duct.
Typically, no preparation is needed for a sialogram.
Before you have a sialogram, tell your doctor:
- if you have a contrast or iodine allergy. You may need medication to prevent an allergic reaction during or after the test.
- if you are taking any prescription or over-the-counter medications. In most cases, the test will not interfere with your medication schedule.
- if you are pregnant or think you are pregnant
If you were given a sedative to take at home, you will not be able to drive yourself to the procedure.
A radiologist will interpret the images obtained during your test. A report will be sent to your physician.
Abnormal results may indicate:
- narrowing of the salivary ducts
- infection or inflammation of the salivary gland
- stones in the salivary ducts
- a tumor in the salivary gland
Blockages or tumors may require further investigation. Follow up tests on your affected glands and ducts might include:
- magnetic resonance imaging (MRI)
- computed tomography (CT) scan
- sialoendoscopy (a tiny camera is used to see inside the salivary gland)