Tomotherapy Image Guided Radiation Therapy
There are a growing number of imaging modalities being implemented to maximize the precision of delivery of radiation therapy. The latest techniques involve volumetric imaging of the patient in the treatment room and automated adjustment of that current position to best match the position of the patient, the tumor and the critical structures obtained in the planning simulation. This chapter discusses the system implemented in the Tomotherapy Hi-Art machine which is basically a helical computed tomography scanner with a megavoltage X-ray source rather than a kilovoltage source. This means that all imaging components are rigidly affixed to a rotating gantry and the same point source is used for imaging and treatment. The system has advantages and disadvantages and processes to maximize the effectiveness of this system are discussed.
KeywordsFiducial Marker Deformable Image Registration Image Guide Radiation Therapy MVCT Image Treatment Planning Compute Tomography
Organs at Risk
Field of View
Image Guided Radiation Therapy
Regions of Interest
Image Value to Density Table
The authors express their appreciation to Yessenia Reyes and Shirley Clark for their assistance in the preparation of this chapter.
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