A 4 Dimensional CT simulation scan provides the radiation oncologist not only with the pictures of the anatomy but allows the radiation oncologist to observe how the anatomy moves during your CT simulation.

How does 4D CT simulation work?

The SOMC Cancer Center provides 4D CT for certain tumors that move significantly with respiration, such as lung cancer. The advanced imaging technology uses a small device that is placed across the body that can sense respiratory motion and transmits the breathing cycle to the computer. While the CT scan is being performed, this correlation is occurring and the CT images are processed to see anatomy in each phase of the respiratory cycle. When complete, a CT video of the images are played together, showing tumor and normal anatomy motion as occurred while you were breathing.


What is the benefit of 4D CT?

Radiation Oncologists know that some tumors move significantly during respiration. They have not always been able to know how much each individual patient’s tumor will move. So margin for tumor motion was added based upon prior knowledge. However, if tumor motion is more than the added margin, you risk missing the target during periods of breathing when tumor is outside the margin. If tumor motion is less than the added margin, you risk giving more radiation to normal tissue that does not need it. Now, with 4D CT, we can see each specific patient’s tumor movement, so the margin for breathing can be customized for you, for accurate tumor targeting and limiting normal tissue that receives radiation. This 4D CT allows the SOMC Cancer Center to perform very precise radiation delivery, and is especially important for SABR treatment.


Who do you call if you have questions?

Call the SOMC Cancer Center at (740) 356-7490 or toll free 1-888-722-8787, or e-mail us if you have questions.