WARF TECHNOLOGIES

One problem associated with intensity modulated radiation therapy (IMRT) is that the precise position, shape and size of the target often changes between the time the plan was developed and the actual treatment time. Computed tomography (CT) is used to monitor the target geometry at the time of radiation treatment so the treatment plan may be adjusted to maximize the benefit of IMRT; however, incorporating a CT machine into the IMRT machine can result in an unnecessarily high imaging radiation dose. Radiation exposure to the patient can be reduced by imaging only the region of interest, but this “partial volume imaging” creates artifacts in the reconstructed image, reducing quality.

UW-Madison researchers have developed a CT machine capable of minimizing the radiation dose while providing an image of desirable quality. The contribution of each radiation beamlet to the quality of the resulting tomographic image varies as a complex function of the internal structure of the patient. Although the structure of the patient is generally unknown, in many cases there is sufficient a priori knowledge about the patient to intelligently select beamlets based on how important each beamlet is to the quality of the image. The CT machine of this invention features a controller that uses a stored model of the patient to control the intensity of radiation in each beamlet based on a calculated contribution of the beamlet to image quality.

• CT imaging
• IMRT

• Controls the intensity of individual beamlets to precisely tailor the radiation dose to achieve the desired image quality
• Significantly decreases the radiation dose to a patient undergoing CT imaging or cinematography
• Beamlet analysis technique is applicable to a variety of different images.
• Works with radiation therapy machines, combined radiation therapy and CT machines, or stand-alone CT systems
• Provides a simple mechanism for independently controlling the beamlets of a CT system
• Capable of working with other forms of beamlet intensity control
• Can work with a predefined radiation plan to reduce additional exposure to the patient
• System can create a stored model from automatically acquired data without requiring manual construction of a patient model.

For More Information About the Inventors

• Bhudatt Paliwal
• Robert Jeraj

Tech Fields

• Medical Imaging : CT
• Radiation Therapy : External beam therapy