Intensity-modulated radiation therapy

Radiation therapy is a tricky business. The goal is to deliver as much radiation as possible to a tumor while sparing nearby noncancerous tissue. A newer approach, called intensity-modulated radiation therapy (IMRT), relaxes the requirement for a uniform dose distribution, yet delivers the radiation more accurately to the cancerous region. This dose distribution, created by small beamlets that can differ in intensity, is expected to produce a treatment field that better conforms to the shape of the tumor. The linear accelerators that deliver radiation to cancer patients now rely on embedded computers for control. The ability to dynamically form and modulate radiation beamlets requires the use of real-time feedback loops. Successful use of embedded computers to control such loops requires the use of radiation-hardened components.