New Image Detector

Acquiring high-quality megavoltage images at extremely low radiation doses will enable more frequent and useful imaging. This is becoming a reality, thanks to a new image detector being developed through RRP-sponsored research at the University of Michigan and the Palo Alto Research Center. The new detection technology may make megavoltage computed tomography (MVCT) possible at clinically practical doses, enabling visualization of tumor volume with the patient in the treatment position, thereby minimizing errors due to patient or organ motion. Moreover, MVCT is subject to less X-ray scatter and is less sensitive to the presence of metal objects (dental fillings or hip implants) in the imaged volume than diagnostic (kilovoltage) CT, where such factors result in severe artifacts. Such benefits will enable the radiotherapy community to better achieve the central goal of radiotherapy—delivering maximum dose to the tumor while sparing normal, healthy tissue and critical organs.

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