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Why is immobilization important during intensity-modulated radiation therapy?
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radiation therapy
External beam radiation therapy (also known as external beam teletherapy, or long-distance therapy) being delivered using a machine known as a linear accelerator.
In intensity-modulated radiation therapy (IMRT), immobilization is critical because the treatment requires highly accurate delineation of the tumor and surrounding healthy structures.
Because IMRT uses specialized technology to deliver high-dose irradiation precisely to the tumor while sparing normal tissue, any movement can compromise this accuracy. The position of a tumor may shift during a single treatment session or between sessions due to internal organ movement caused by breathing or digestion. Immobilization helps ensure the patient remains in the correct position, allowing the radiation beams to conform precisely to the tumor's shape as intended.1