Tests & scales

Modified Barium Swallow Study

Also written as MBSS, MBS, VFSS, videofluoroscopy, videofluoroscopic swallow study, modified barium swallow.

A moving X-ray of your swallow: you eat and drink small amounts mixed with barium so the team can watch the food travel in real time.

A modified barium swallow study is an X-ray video of you swallowing. You sit or stand next to an X-ray machine and take small bites and sips of food and drink that have been mixed with barium. Barium is a chalky white contrast material that shows up on X-ray, so the team can see exactly where the food and liquid go.

The study is usually done in a hospital radiology room by a speech-language pathologist working together with a radiologist. It is recorded as a moving picture rather than a single snapshot, because a swallow takes about a second and the team needs to see each step: the mouth, the throat, and the top of the food pipe.

You may see this test written several different ways. "Modified barium swallow study" (MBSS), "videofluoroscopic swallow study" (VFSS), and "videofluoroscopy" all refer to the same procedure. During the study the speech-language pathologist may also try small changes, such as a different head position or a smaller sip, and watch whether the swallow looks different. That is a normal part of the test, not a sign that something went wrong.

An exam done from the outside cannot show what happens once food passes the back of the tongue. This moving X-ray lets the team see the swallow itself, including whether anything travels toward the airway, and check whether small adjustments change what they see. What your own images showed, and what comes next, is a conversation for your care team.