A sialogram is a test your doctor can use to diagnose a blocked salivary gland or duct in your mouth. The procedure uses X-rays. It’s also called a ptyalogram.
Your 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’re above your jaw in front of your ears. Your submandibular glands are below your jawbone on both sides of your jaw. Your sublingual glands are 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
Saliva adds moisture to food when it enters your mouth. The moisture helps with chewing and swallowing. It also helps prevent choking. Enzymes in saliva initiate the digestion process before you swallow food.
Saliva also works to keep your 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.
Your doctor can use a sialogram to evaluate blockages in a salivary duct or gland. Your doctor may recommend a sialogram if you have one or more of the following symptoms:
- a constant abnormal or foul taste in your mouth
- an 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 can be 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, which is a condition in which patches of inflammation occur throughout the body
- Sjogren’s syndrome, which is an autoimmune disorder that causes dry mouth and eyes
Salivary gland tumors are rare. They occur most often in the parotid gland. The growths slowly increase in size, expanding the gland.
You should tell your doctor the following before you have a sialogram:
- Tell them if you have a contrast or iodine allergy. You may need medication to prevent an allergic reaction during or after the test.
- Tell them if you’re taking any prescription or over-the-counter medications. In most cases, the test will not interfere with your medication schedule.
- Tell them if you’re pregnant or think you’re pregnant.
If your doctor gives you a sedative to take at home, you won’t be able to drive yourself to the procedure. If that’s the case, you’ll need to arrange for transportation.
No other preparation is typically necessary for a sialogram.
A sialogram is normally an outpatient procedure. It typically takes place in the radiology department of a hospital or clinic. The procedure typically takes about 30 minutes. It may take longer if the duct opening is difficult to locate.
Your doctor or an X-ray technician will perform the sialogram. They’ll give you a germ-killing mouthwash. They may give you a sedative to help you remain calm. Stronger sedation may be necessary if you’re unable to remain still.
You’ll lie on your back on an X-ray table. You’ll have to open your mouth very wide. No numbing agent is used. The procedure causes only minimal discomfort.
They’ll take an X-ray. This will show if there are any stones that might prevent the contrast material, or dye, from entering the ducts and reaching the gland.
They’ll place a small, flexible tube called a catheter in the opening of the salivary duct. They may ask you 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 doctor may need to examine your 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.
They may give you lemon juice to increase the amount of saliva in your mouth. They’ll take additional images to observe how your saliva drains into your mouth.
After the sialogram is over, the contrast material will drain into your mouth. They may instruct you to massage your salivary glands. This will aid in draining the dye. The dye may taste bitter. It’s 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 learn important information about your health. The risk of radiation exposure is considered acceptable for this reason. Special considerations may be necessary for pregnant women, women who are breast-feeding, and children. These groups have an increased risk of harm from radiation.
A sialogram is a minimally invasive technique. However, it carries a small risk of damage or puncture to the salivary duct, swelling, and tenderness. Infection is a rare complication. Contact your doctor if you experience:
- soreness or pain that continues after 24 hours
- swelling or bleeding of the salivary duct
- a fever
A radiologist will interpret the images from your test. They’ll send a report to your doctor. 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:
- an ultrasound
- an MRI scan
- a CT scan
- a sialoendoscopy, which involves using a tiny camera to see inside the salivary gland
- a biopsy