What are the benefits of real-time MRI-guided radiation to treat cancer?

Percy Lee, MD
Percy Lee, MD on behalf of UCLA Health
Radiation Oncology
Real-time magnetic resonance imaging (MRI)-guided radiation is especially useful for mobile tumors, which often change position in unpredictable ways. This movement occurs for a number of reasons, including the person’s respiration, heartbeat and muscle contractions. For example, a lung tumor can move an inch or more every few seconds as the person breathes. Tumor movement can also be due to weight changes or the tumor’s response to other treatments. Cancers expected to benefit from non-stop MRI imaging include lung, prostate, bladder and pancreas, along with cancers of the head and neck and central nervous system.

During treatment, MRI-guided radiation captures a steady stream of soft-tissue images in real time and compares them to the planned treatment margins. If the tumor strays outside prescribed margins, the machine can turn the beam off until the tumor returns to its prescribed location.

Current practice allows radiation oncologists to design treatment plans based on images taken days or weeks before the treatment date. If doctors suspect tumor movement from weight loss or other reasons, redesigning a plan can take several days. MRI-guided radiation software allows radiation oncologists to adapt radiation in real time when necessary by creating a customized “plan-of-the-day” for each person. In doing so, radiation that otherwise would have hit healthy tissue is redirected to hone in on malignant tissue, increasing the probability of exact delivery and improving outcomes.

This content originally appeared online at UCLA Health

Continue Learning about Magnetic Resonance Imaging (MRI)

How does a functional magnetic resonance imaging scan work?
Discovery HealthDiscovery Health
The technology for a functional magnetic resonance imaging (fMRI) scan is based on the same kind tha...
More Answers
How can MRI help a stroke patient who doesn't know when the stroke started?
Anthony CirilloAnthony Cirillo
Magnetic resonance imaging, or MRIs, might be able to help physicians figure out if clot-busting dru...
More Answers
What is a functional magnetic resonance imaging scan?
Discovery HealthDiscovery Health
A functional magnetic resonance imaging (fMRI) scan can help diagnose diseases of the brain and may ...
More Answers
What to Expect From an MRI
What to Expect From an MRI

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.