Magnetic Resonance Imaging (MRI) is a sophisticated medical tool that uses strong magnetic fields and radio waves to generate detailed, cross-sectional pictures of organs and tissues within the body. The procedure is non-invasive and provides physicians with important visual information for diagnosis and treatment planning. To produce these clear anatomical images, the process relies completely on the patient remaining absolutely still throughout the scan.
Why Stillness is Critical for MRI Images
The sensitivity of MRI technology means that even small, involuntary movements like a cough can negatively affect the image quality. An MRI sequence acquires data over a period of time, often lasting a few minutes, to construct a complete image slice. Movement during this acquisition process changes the spatial location of the tissue, resulting in image degradation known as a “motion artifact.”
These artifacts frequently appear as blurring or “ghosting,” where the moving structures are smeared across the image. The blurring occurs because the system incorrectly maps the signal location, resulting in a non-diagnostic image. Since the system assumes a static environment, the smallest head twitch or abdominal movement introduces errors that make the image useless for the radiologist.
What Happens If You Move During the Scan
If an involuntary movement, such as a cough or a twitch, occurs during an active sequence, the patient is equipped with a mechanism to communicate this immediately. Patients are typically given a small squeeze ball or a button to alert the technologist, who is monitoring the scan from the control room. The technologist, who can see and speak with the patient via an intercom, will likely pause the current sequence.
Movement during a sequence means that the data collected for that specific image slice is compromised and must be discarded. The technologist will restart only the specific imaging sequence that was interrupted, which usually lasts just a few minutes, rather than requiring the entire procedure to be repeated. Patients should communicate their need to cough or shift before the involuntary action takes place to allow the technologist to pause the data collection.
Strategies for Minimizing Coughing and Movement
Preparation is the most effective tool a patient has to minimize the risk of coughing or moving during the MRI. Before the scan begins, it is helpful to inform the technologist about any existing conditions, such as a chronic cough, seasonal allergies, or a persistent tickle in the throat. In some cases, the facility may suggest using a mild cough suppressant or having a lozenge before the scan to keep the throat lubricated and reduce irritation.
Practicing focused breathing before and during the scan can help manage anxiety-induced movement or suppress the urge to cough. A slow, deep swallow can sometimes eliminate a throat tickle without causing significant movement. For abdominal or chest scans, patients are often given specific breath-holding instructions. Being well-rested and having used the restroom beforehand also contributes to the ability to remain still.