Linear accelerator cutaway.

The ONCOR Avant-Garde linear accelerator is a high-tech medical device used in the latest oncology clinical treatment applications such as Image-Guided Radiation Therapy (IGRT). A medical linear particle accelerator produces a powerful electron beam of x-ray radiation which is spread out and/or confined by scanning magnets and movable tungsten alloy leaf vanes, or a multi-vane 'collimator,' to produce a safe level of radiation in the exact location needed for treatment. The beam is focused with MVision which uses cone-beam CT images. The ONCOR Expression is used in Stereotactic Radiation Therapy and Surgery (SRT/SRS), Intensity-Modulated Radiation Therapy (IMRT), and 3D IGRT. Expression uses MVision Megavoltage Cone Beam Imaging to provide a 3D Image-Guided Radiation Therapy (IGRT) solution.

The PRIMUS Linear Accelerator focuses the maximum amount of radiation to a tumor with a minimum dose of radiation to surrounding tissue, using IMRT technology and the Optifocus graphical user interface. Siemens Medical Solutions USA, Inc. is located in Concord, California.